WorldWideScience

Sample records for narcea gold belt

  1. Metallogenic epoch of the Jiapigou gold belt, Jilin Province, China

    Indian Academy of Sciences (India)

    Metallogenic epoch of the Jiapigou gold belt, Jilin Province, China: ... The Jiapigou gold belt is located on the northern margin of the North China Craton, and is one of the ... 29, Xueyuan Road, Beijing 100083, People's Republic of China.

  2. The geology of the gold deposits of Prestea gold belt of Ghana ...

    African Journals Online (AJOL)

    This paper presents the geology of the gold deposits along the Prestea gold belt of Ghana to assist exploration work for new orebodies along the belt. Prestea district is the third largest gold producer in West Africa after Obuasi and Tarkwa districts (over 250 metric tonnes Au during the last century). The gold deposits are ...

  3. The Tintina Gold Belt - A global perspective

    Science.gov (United States)

    Goldfarb, Richard J.; Hart, Craig J.R.; Miller, Marti L.; Miller, Lance D.; Farmer, G. Lang; Groves, David I.; Tucker, Terry L.; Smith, Moira T.

    2000-01-01

    The so-called Tintina Gold Belt extends for more than 1000 km along the length of the northern North American Cordillera. Middle to Late Cretaceous Au deposits within the belt have various similar characteristics, among which are a spatial and temporal association with magmatism; Bi-W-Te signatures in deposits hosted by granitod stocks and As-Sb signatures where hosted by sedimentary rocks and dyke systems; and δ180 values consistently > 12 per mil for Au-bearing quartz. Nevertheless significant differences in structural styles, levels of deposit emplacement, ore-fluid chemistry, and Au grades suggest that the characteristics represent a broad range of deposit types. Many of these are best classified as orogenic Au deposits in the Yukon-Tanana terrane, as epithermal and porphyry-style Au deposits in the Kuskokwim region, and as Au-bearing, granite-related veins and stockworks, replacements, and skarns, as well as associated polymetallic lodes, in central Yukon. The diverse types of Au deposits and associated plutons of the Tintina Gold Belt collectively define a 45-m.y.-long period of arc magmatism that migrated northwesterly, for about 1000 km, across the active collisional margin of Cretaceous northwestern North America. The initiation of fluid flow and plutonism in Albian time seems to correlate with the onset of oblique subduction and dextral strike-slip on the Denali-Farewell, Tintina-Kaltag, and related fault systems. Initial Au-vein formation and subduction-related magmatism at about 115-110 Ma (e.g., including the Goodpaster and Fortymile districts), within the seaward side of the Yukon-Tanana terrane, correlate with the arrival of the Wrangellia superterrane off the continental margin. Dextral translation of the allochthonous Wrangellia block was associated with the migration of the thermal pulse to the northwest at about 95-90 Ma. Orogenic (or so­ called mesotherrnal) and granitoid-related Au deposits formed across the width of the Yukon

  4. Geochemistry of Gold Deposits in Anka Schist Belt, Northwestern ...

    African Journals Online (AJOL)

    Gold quartz veins have been identified associated with the rock formations of the Anka Schist Belt forming eight gold deposits that include Kuba I, Kuba II, Doka, Dumi I, Dumi II, Zurzurfa I, Zurzurfa II, Jameson and Kwali. The present study involves the use of major and trace elements to characterize some of the features that ...

  5. Geochemistry of Gold Deposits in Anka Schist Belt, Northwestern ...

    African Journals Online (AJOL)

    HP USER

    ABSTRACT. Gold quartz veins have been identified associated with the rock formations of the Anka Schist Belt forming eight gold deposits that include Kuba I, Kuba II, Doka, Dumi I, Dumi II, Zurzurfa I, Zurzurfa II, Jameson and Kwali. The present study involves the use of major and trace elements to characterize some of the.

  6. Strain partitioning in the footwall of the Somiedo Nappe: structural evolution of the Narcea Tectonic Window, NW Spain

    Science.gov (United States)

    Gutiérrez-Alonso, Gabriel

    1996-10-01

    The Somiedo Nappe is a major thrust unit in the Cantabrian Zone, the external foreland fold and thrust belt of the North Iberian Variscan orogen. Exposed at the Narcea Tectonic Window are Precambrian rocks below the basal decollement of the Somiedo Nappe, which exhibit a different deformation style than the overlying Paleozoic rocks above the basal decollement. During Variscan deformation, folding and widespread subhorizontal, bedding-parallel decollements were produced in the hanging wall within the Paleozoic rocks. Vertical folding, with related axial-planar cleavage at a high angle to the decollement planes, developed simultaneously in the upper Proterozoic Narcea Slates of the footwall, below the detachment. The relative magnitude of finite strain, measured in the footwall rocks, diminishes towards the foreland. These observations indicate that (1) significant deformation may occur in the footwall of foreland fold and thrust belts, (2) the shortening mechanism in the footwall may be different from that of the hanging wall, and (3) in this particular case, the partitioning of the deformation implies the existence of a deeper, blind decollement surface contemporaneous with the first stages of the foreland development, that does not crop out in the region. This implies a significant shortening in the footwall, which must be taken into account when restoration and balancing of cross-sections is attempted. A sequential diagram of the evolution of the Narcea Tectonic Window with a minimum shortening of 85 km is proposed, explaining the complete Variscan evolution of the foreland to hinterland transition in the North Iberian Variscan orogen.

  7. Metallogenic epoch of the Jiapigou gold belt, Jilin Province, China ...

    Indian Academy of Sciences (India)

    29, Xueyuan Road, Beijing 100083, People's Republic of China. 2Beijing Research .... terrane, which is separated from the central Asian orogenic belt .... Stage I formed the main body of quartz veins ...... size (20–25 μm) fluid inclusions can be observed, although most ..... Canada and Western Australia (Goldfarb et al. 2001 ...

  8. Archaean Gold Mineralization in an Extensional Setting: The Structural History of the Kukuluma and Matandani Deposits, Geita Greenstone Belt, Tanzania

    Directory of Open Access Journals (Sweden)

    Shimba D. Kwelwa

    2018-04-01

    Full Text Available Three major gold deposits, Matandani, Kukuluma, and Area 3, host several million ouncez (Moz of gold, along a ~5 km long, WNW trend in the E part of the Geita Greenstone Belt, NW Tanzania. The deposits are hosted in Archaean volcanoclastic sediment and intrusive diorite. The geological evolution of the deposits involved three separate stages: (1 an early stage of syn-sedimentary extensional deformation (D1 around 2715 Ma; (2 a second stage involving overprinting ductile folding (D2–4 and shearing (D5–6 events during N-S compression between 2700 and 2665 Ma, coeval with the emplacement of the Kukuluma Intrusive Complex; and (3 a final stage of extensional deformation (D7 accommodated by minor, broadly east-trending normal faults, preceded by the intrusion of felsic porphyritic dykes at ~2650 Ma. The geometry of the ore bodies at Kukuluma and Matandani is controlled by the distribution of magnetite-rich meta-ironstone, near the margins of monzonite-diorite bodies of the Kukuluma Intrusive Complex. The lithological contacts acted as redox boundaries, where high-grade mineralization was enhanced in damage zones with higher permeability, including syn-D3 hydrothermal breccia, D2–D3 fold hinges, and D6 shears. The actual mineralizing event was syn-D7, and occurred in an extensional setting that facilitated the infiltration of mineralizing fluids. Thus, whilst gold mineralization is late-tectonic, ore zone geometries are linked to older structures and lithological boundaries that formed before gold was introduced. The deformation-intrusive history of the Kukuluma and Matandani deposits is near identical to the geological history of the world-class Nyankanga and Geita Hill deposits in the central part of the Geita Greenstone Belt. This similarity suggests that the geological history of much of the greenstone belt is similar. All major gold deposits in the Geita Greenstone Belt lack close proximity to crustal-scale shear zones; they are associated

  9. GOLD MINERAL PROSPECTING USING PHASED ARRAY TYPE L-BAND SYNTHETIC APERTURE RADAR (PALSAR SATELLITE REMOTE SENSING DATA, CENTRAL GOLD BELT, MALAYSIA

    Directory of Open Access Journals (Sweden)

    A. Beiranvand Pour

    2016-06-01

    Full Text Available The Bentong-Raub Suture Zone (BRSZ of Peninsular Malaysia is one of the significant structural zones in Sundaland, Southeast Asia. It forms the boundary between the Gondwana-derived Sibumasu terrane in the west and Sukhothai arc in the east. The BRSZ is also genetically related to the sediment-hosted/orogenic gold deposits associated with the major lineaments and form-lines in the central gold belt Central Gold Belt of Peninsular Malaysia. In tropical environments, heavy tropical rainforest and intense weathering makes it impossible to map geological structures over long distances. Advances in remote sensing technology allow the application of Synthetic Aperture Radar (SAR data in geological structural analysis for tropical environments. In this investigation, the Phased Array type L-band Synthetic Aperture Radar (PALSAR satellite remote sensing data were used to analyse major geological structures in Peninsular Malaysia and provide detailed characterization of lineaments and form-lines in the BRSZ, as well as its implication for sediment-hosted/orogenic gold exploration in tropical environments. The major geological structure directions of the BRSZ are N-S, NNE-SSW, NE-SW and NW-SE, which derived from directional filtering analysis to PALSAR data. The pervasive array of N-S faults in the study area and surrounding terrain is mainly linked to the N-S trending of the Suture Zone. N-S striking lineaments are often cut by younger NE-SW and NW-SE-trending lineaments. Gold mineralized trends lineaments are associated with the intersection of N-S, NE-SW, NNW-SSE and ESE-WNW faults and curvilinear features in shearing and alteration zones. Lineament analysis on PALSAR satellite remote sensing data is a useful tool for detecting the boundary between the Gondwana-derived terranes and major geological features associated with suture zone especially for large inaccessible regions in tropical environments.

  10. Metallogenesis of Precambrian gold deposits in the Wutai greenstone belt: Constrains on the tectonic evolution of the North China Craton

    Directory of Open Access Journals (Sweden)

    Ju-Quan Zhang

    2018-03-01

    Full Text Available The Wutai greenstone belt in central North China Craton (NCC hosts a number of Precambrian gold deposits and ore occurrences. Based on the host rock association, these can be divided into Banded Iron Formation (BIF, meta-volcano-sedimentary and meta-conglomerate types. The two former types formed during ∼2.5–2.3 Ga and the third one at ∼1.85 Ga. The characteristics of these Precambrian gold deposits are broadly similar with those of the orogenic gold deposits. Based on available geochronological data, here we reconstruct the major tectonic events and their relationship with gold mineralization in the Wutai-Hengshan-Fuping region during Neoarchean to Paleoproterozoic as follows. (1 ∼2.6–2.5 Ga: widespread intrusion of tonalite-trondhjemite-granodiorite (TTG magmas in the Hengshan terrane and Fuping continental arc, formation of the Wutai volcanic arc in the southern margin of Hengshan terrane with granitoids emplacement, and the Hengshan-Wutai intra-oceanic arc accretion to the Fuping arc at the end of Neoarchean. (2 ∼2.5–2.3 Ga: the subduction of Hengshan arc from north leading to persistent magmatism and orogenic gold mineralization. (3 ∼2.2–2.1 Ga: extension leading to the formation of graben structure in the Wutai and Fuping region, deposition of the Hutuo and Wanzi Group sediments, formation of placer gold through erosion of the orogenic gold deposits. (4 ∼2.2–2.0 Ga: widespread magmatism in the Wutai-Hengshan-Fuping region. (5 ∼1.95–1.8 Ga: regional metamorphism associated with collision of the Western and Eastern Blocks of the NCC and associated orogenic gold deposits. The multiple subduction-accretion-collision history and subsequent deep erosion has significantly affected most of the Precambrian gold deposits in the Wutai greenstone belt.

  11. Absolute timing of sulfide and gold mineralization: A comparison of Re-Os molybdenite and Ar-Ar mica methods from the Tintina Gold Belt, Alaska

    Science.gov (United States)

    Selby, D.; Creaser, R.A.; Hart, C.J.R.; Rombach, C.S.; Thompson, J.F.H.; Smith, Moira T.; Bakke, A.A.; Goldfarb, R.J.

    2002-01-01

    New Re-Os molybdenite dates from two lode gold deposits of the Tintina Gold Belt, Alaska, provide direct timing constraints for sulfide and gold mineralization. At Fort Knox, the Re-Os molybdenite date is identical to the U-Pb zircon age for the host intrusion, supporting an intrusive-related origin for the deposit. However, 40Ar/39Ar dates from hydrothermal and igneous mica are considerably younger. At the Pogo deposit, Re-Os molybdenite dates are also much older than 40Ar/39Ar dates from hydrothermal mica, but dissimilar to the age of local granites. These age relationships indicate that the Re-Os molybdenite method records the timing of sulfide and gold mineralization, whereas much younger 40Ar/39Ar dates are affected by post-ore thermal events, slow cooling, and/or systemic analytical effects. The results of this study complement a growing body of evidence to indicate that the Re-Os chronometer in molybdenite can be an accurate and robust tool for establishing timing relations in ore systems.

  12. Delineation of Gold Mineralization Zone using Resistivity and Very Low Frequency Electromagnetic Methods around, North Singhbhum Mobile Belt, India.

    Science.gov (United States)

    Upadhyay, A.; Panda, K. P.; Singh, A.; Sharma, S. P.

    2017-12-01

    The results of electrical resistivity and VLF electromagnetic surveys are presented in this study to delineate the suitable geological structure associated with gold mineralization near Lawa Village (Seraikela-Kharsawan, Jharkhand), India. The area under observation lies in North Singhbhum Mobile Belt (NSMB) which is bounded by Chotanagpur Gneiss Complex in north and Archean Singhbhum Craton in the south. Shear zone of the study area, trending E-W, is mainly associated with Cu-U mineralization which is also associated with gold. Previous geological studies have revealed that this region can be a potential site for gold prospects within NSMB. A comprehensive electrical resistivity imaging and very low frequency surveys have been performed around Lawa village to outline appropriate conducting zones, with their lateral extension and depth extent, which may be associated with gold mineralization. Resistivity survey done using Dipole-Dipole multi-electrode array reveals multiple zones of mineralization separated by variable distances. The VLF data in the current study was tainted by non-stationary and non-linear noises which cannot be eliminated by standard filtering techniques. Therefore to restore signals with significant geologic information empirical mode decomposition (EMD) technique was used. The noise free data obtained was then processed using Fast Imaging technique to obtain apparent current density pseudo-sections for interpretation. Interpretation and analysis of results from each investigating survey demonstrate a steeply dipping conductor with E-W strike direction along the shear zone. These conductive zones are characterized by low resistivity and high current density values.

  13. Map showing reconnaissance geochemistry in the gold-pyrophyllite belt of northwestern Moore County, North Carolina

    Science.gov (United States)

    Lesure, Frank G.

    1981-01-01

    Traces of gold and molybdenum are widely disseminated in an area approximately 35 km long and 10 km wide in northwestern Moore County, N.C.  At least 2540 oz. of gold were recovered from 16 or more mines and prospects between 1880 and 1910.  One hundred and ninety rock samples out of 244 collected from old gold mines, pyrophyllite deposits and along roads contain gold quantities ranging from 0.02 to 2.4 parts per million.  In addition, 43 samples out of the 244 taken contain molybdenum in amounts ranging from 4 to 500 parts per million.

  14. Radiological Impact Study of the Coal-Fired Power Plant of Narcea

    Energy Technology Data Exchange (ETDEWEB)

    Robles, B.; Baeza, A.; Mora, J. a.; Corbacho, J. a.; Trueba, C.; Guillen, J.; Rodriguez, Miralles, Y.

    2014-04-01

    Coal, fuel used in thermal power plants for electricity production, contains variable concentrations of naturally occurring radionuclides from natural disintegration series of {sup 2}38U, {sup 2}35U, {sup 2}32Th and also the 40K, which are enhanced in the wastes and coproducts due to the industrial process. For this reason, natural radionuclides which are part of the noncombustible fraction of coal, except those volatiles which incorporate directly to the flue gases, concentrates and are partitioned between fly ashes and bottom ashes. This enhancement could cause, to the workers of the installation and to members of the public around the plant, an increase in the exposure which should be assessed under the radiation protection point of view. Present report collect the results obtained from a screening assessment of the radiological impact derived from the normal operation of the Narcea coal-fired power plant. The project where this assessment was performed is part of a bigger project which is jointly developed by the Unit of Radiation Protection of the Public and the Environment (UPRPYMA) of CIEMAT and the Environmental Radioactivity Laboratory of the Extremadura University (LARUEX) in agreement with the Spanish Association of the Electrical Industry (ENUSA). (Author)

  15. Timing of multiple hydrothermal events in the iron oxide-copper-gold deposits of the Southern Copper Belt, Carajás Province, Brazil

    Science.gov (United States)

    Moreto, Carolina P. N.; Monteiro, Lena V. S.; Xavier, Roberto P.; Creaser, Robert A.; DuFrane, S. Andrew; Melo, Gustavo H. C.; Delinardo da Silva, Marco A.; Tassinari, Colombo C. G.; Sato, Kei

    2015-06-01

    The Southern Copper Belt, Carajás Province, Brazil, hosts several iron oxide-copper-gold (IOCG) deposits, including Sossego, Cristalino, Alvo 118, Bacuri, Bacaba, Castanha, and Visconde. Mapping and U-Pb sensitive high-resolution ion microprobe (SHRIMP) IIe zircon geochronology allowed the characterization of the host rocks, situated within regional WNW-ESE shear zones. They encompass Mesoarchean (3.08-2.85 Ga) TTG orthogneiss, granites, and remains of greenstone belts, Neoarchean (ca. 2.74 Ga) granite, shallow-emplaced porphyries, and granophyric granite coeval with gabbro, and Paleoproterozoic (1.88 Ga) porphyry dykes. Extensive hydrothermal zones include albite-scapolite, biotite-scapolite-tourmaline-magnetite alteration, and proximal potassium feldspar, chlorite-epidote and chalcopyrite formation. U-Pb laser ablation multicollector inductively coupled mass spectrometry (LA-MC-ICP-MS) analysis of ore-related monazite and Re-Os NTIMS analysis of molybdenite suggest multiple Neoarchean (2.76 and 2.72-2.68 Ga) and Paleoproterozoic (2.06 Ga) hydrothermal events at the Bacaba and Bacuri deposits. These results, combined with available geochronological data from the literature, indicate recurrence of hydrothermal systems in the Southern Copper Belt, including 1.90-1.88-Ga ore formation in the Sossego-Curral ore bodies and the Alvo 118 deposit. Although early hydrothermal evolution at 2.76 Ga points to fluid migration coeval with the Carajás Basin formation, the main episode of IOCG genesis (2.72-2.68 Ga) is related to basin inversion coupled with Neoarchean (ca. 2.7 Ga) felsic magmatism. The data suggest that the IOCG deposits in the Southern Copper Belt and those in the Northern Copper Belt (2.57-Ga Salobo and Igarapé Bahia-Alemão deposits) do not share a common metallogenic evolution. Therefore, the association of all IOCG deposits of the Carajás Province with a single extensive hydrothermal system is precluded.

  16. Origin of ore-forming fluids of the Haigou gold deposit in the eastern Central Asian Orogenic belt, NE China: Constraints from H-O-He-Ar isotopes

    Science.gov (United States)

    Zeng, Qingdong; He, Huaiyu; Zhu, Rixiang; Zhang, Song; Wang, Yongbin; Su, Fei

    2017-08-01

    The Haigou lode deposit contains 40 t of gold at an average grade of 3.5 g/t, and is one of the largest deposits in the Jiapigou gold belt located along the eastern segment of the northern margin of the North China Craton. The deposit comprises 15 gold-bearing quartz veins hosted in a Carboniferous monzonite-monzogranite stock. Cretaceous dikes consisting of diorite, diabase, and granodiorite porphyries are well developed in the deposit. The diorite porphyry dikes (130.4 ± 6.3 Ma) occur together with gold-bearing quartz veins in NNE- and NE-striking faults. Gold-bearing quartz veins crosscut the diorite porphyry dikes, and the veins are in turn crosscut by E-W-striking 124.6 ± 2.2 Ma granodiorite porphyry dikes. The mineralization mainly occurs as auriferous quartz veins with minor amounts of sulfide minerals, including pyrite, galena, chalcopyrite, and molybdenite. Gold occurs as either native gold or calaverite. Common gangue minerals in the deposit include quartz, sericite, and calcite. The deposit is characterized by various types of hydrothermal alteration, including silicification, sericitization, chloritization, potassic alteration, and carbonatization. Three stages of hydrothermal activity have been recognized in the deposit: (1) a barren quartz stage; (2) a polymetallic sulfide (gold) stage; (3) a calcite stage. Fluid inclusions in hydrothermal pyrites have 3He/4He ratios of 0.3 to 3.3 Ra and 40Ar/36Ar ratios of 351 to 1353, indicating mixing of fluids of mantle and crustal origin. Hydrothermal quartz yielded δ18O values of -1.3‰ to +7.2‰ and δD values of fluid inclusions in the quartz vary between -80‰ and -104‰. These stable isotope data also suggest mixing of magmatic and meteoric fluids. Noble gas and stable isotopic data suggest that the ore fluids have a predominant mantle source with a significant crustal component. Based on the spatial association of gold-bearing quartz veins with early Cretaceous intrusions, and the H-O-He-Ar isotopic

  17. Bare face red-brown bricks manufactured with fly ash from the Narcea (Asturias Coal Power Plan

    Directory of Open Access Journals (Sweden)

    Ayesta, G.

    1999-12-01

    Full Text Available Fly ash, from the Coal Power Plant of Narcea (Asturias, has been used to determine its possible use as a raw material in the bare face red-brown brick manufacture. The correct mould of a ceramic material demands a paste with an adequate plasticity. So, the optimum compositions of humidity, lubricant (talc and binder (white dextrin have been investigated. The samples were made by compressing paste into a mould using varying values of pressure and boiling temperature once the cooling speed had been established. Finally, the cooked pieces were submitted to trials demanded by the Basic Construction Norm, to see if they met the required specifications concerning Water Absorption, Suction, Contraction, Resistance to Freezing, Efflorescence and Compressive Strength.

    Se caracterizan las cenizas volantes de la Central Térmica del Narcea (Asturias para determinar su utilización como materia prima en la obtención de ladrillos cara vista. El moldeo correcto de una pieza cerámica exige trabajar una pasta con una adecuada plasticidad, para ello se investiga cuál ha de ser la composición óptima de la misma, en cuanto a: humedad, cantidad de lubricante (talco y de ligante (dextrina blanca. El conformado de las piezas o ladrillos se realiza por prensado, utilizando distintos valores de presión, así como la temperatura de cocción, una vez establecida la velocidad de enfriamiento. Finalmente, las piezas cocidas se someten a los ensayos exigidos por la Norma Básica de Edificación, para ver si cumplen las especificaciones requeridas en cuanto a: Absorción de agua. Succión, Contracción, Heladicidad, Eflorescencia y Resistencia a la compresión.

  18. Structural control on gold mineralization in the Satulinmäki and Riukka prospects, Häme Schist Belt, southern Finland

    Directory of Open Access Journals (Sweden)

    Kerstin Saalmann

    2007-01-01

    Full Text Available The Satulinmäki and Riukka prospects located in the Häme Schist Belt in southern Finland are dominated by mafic and intermediate to felsic metavolcanic rocks of the Forssa Group formed in a continental arc setting. This magmatic belt formed some 1890–1880 Ma ago and has been deformed during the Svecofennian orogeny. The dominant penetrative foliation is represented by Sn+1, which is axial planar to cm- to dm-scale iscolinal Fn+1 folds and thus parallel to the layering Sn. Associated ductile shearing might reflect early thrusting. Dn+2 post-dating peak metamorphism is characterized by small-scale to regional-scale refolding of Fn+1 folds around ~SW-NE fold axes. This phase is transitional to development of SW-NE to WSW-ENE and NW-SE striking shear zones and faults formed due to dextral transpressionduring Dn+3 at retrograde conditions crossing the brittle-ductile transition. Many mineralized quartz veins have formed during this event. Later faults and quartz veins and reactivation of pre-existing structures during Dn+4 indicate rotation of the stress field to ~NESWoriented compression. A clear ~SW-NE trend of sulphide mineralization and elevated gold contents and the spatial association to Dn+3 quartz veins, shear zones and faults suggest a strong structural control, typical of orogenic gold deposits, and that mineralization took place during Dn+3. The controlling structures, (i WSW-ENE to SW-NE shear zones and faults and (ii NW-SE oriented fault, are second and third order structures to major regional-scale shear zones. The fault zones and their intersection points impart a directional permeability so that the mineralising fluids were channelled along dilatant zones. Approximately (WNW-(ESE trending faults being (reactivated as extensional faults or dilatant shear planes during Dn+3 transpression with WNW-ESE to NW-SE oriented compression direction could have acted as conduits for fluids during upward flow from deeper crustal level. Future

  19. A cryptic Early Palaeozoic event in the Narcea Antiform? 40Ar/39Ar amphibole data in the Puente de Selce granitoid

    OpenAIRE

    Gutiérrez Alonso, Gabriel; Fernández Suárez, J.; Keppie, J. D.; Ortega Rivera, M. A.; Lee, J. K. W.; Murphy, J. B.

    2005-01-01

    Las edades 40Ar/39Ar obtenidas a partir de anfíboles del granitoide Neoproterozoico de Puente de Selce, localizado en el Antiforme del Narcea junto con la existencia de fábricas de deformación relictas generadas en condiciones de media-alta temperatura en las mismas rocas puede ser interpretada como debida a un evento críptico de edad Paleozoico Inferior fuertemente retrabajado durante la deformación varisca. La naturaleza y la cinemática de este posible evento no pueden precisars...

  20. Rare earth chemistry of gold-bearing sedimentary carbonate horizons from the Abitibi Greenstone Belt, Ontario, Canada

    International Nuclear Information System (INIS)

    Gibson, I.L.; Roberts, R.G.; Reading, D.J.R.

    1984-01-01

    The ankerite, gold ore bodies of the Dome Mine, Timmins, Ontario are interflow units, 1 to 3 m thick in a sequence of tholeiitic basalts. The units consist of discontinuous layers of ferroan dolomite, chert and pyroclastic material, and laminations of iron sulfides, tourmaline, and graphite. They have been interpreted as sediments on the basis of their internal structure. Seven Rare Earth elements (REE) (Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb) were determined by instrumental neutron activation analysis, on 10 samples of carbonate material from the ankerite units. The chondrite normalized REE plots have relatively flat patterns with, in some cases, positive Europium anomalies. The flat patterns suggest that the fluids from which the carbonate precipitated was in equilibrium with volcanic rocks of tholeiitic and komatiitic composition. The positive Europium anomalies imply that the fluids were reducing at times. Such patterns are characteristic of Archaean sediments and also the precipitates associated with the discharge of hydrothermal solutions from vents on the East Pacific Rise

  1. Geochemical behavior under tropical weathering of the Barama-Mazaruni greenstone belt at Omai gold mine, Guiana Shield

    Energy Technology Data Exchange (ETDEWEB)

    Voicu, G. [Universite du Quebec a Montreal (Canada). Dept. des Sciences de la Terre et de l' Atmosphere; Omai Gold Mines, Georgetown (Guyana); Bardoux, M. [Universite du Quebec a Montreal (Canada). Dept. des Sciences de la Terre et de l' Atmosphere

    2002-07-01

    Mineralogical, petrographical, and geochemical studies of the weathering profile have been carried out at Omai Au mine, Guyana. The area is underlain by felsic to mafic volcanic and sedimentary rocks of the Barama-Mazaruni Supergroup, part of the Paleoproterozoic greenstone belts of the Guiana Shield. Tropical rainy climate has favoured extensive lateritization processes and formation of a deeply weathered regolith. The top of the weathering profile consists of lateritic gravel or is masked by the Pleistocene continental-deltaic Berbice Formation. Mineralogical composition of regolith consists mainly of kaolinite, goethite and quark, and subordinately sericite, feldspar, hematite, pyrite, smectite, heavy minerals, and uncommon mineral phases (nacrite, ephesite, corrensite, guyanaite). A specific feature of the weathering profile at Omai is the preservation of fresh hydrothermal pyrite in the saprolith horizon. Chemical changes during the weathering processes depend on various physicochemical and structural parameters. Consequently, the depth should not be the principal criterion for comparison purposes of the geochemical behavior within the weathering profile, but rather an index that measures the degree of supergene alteration that has affected each analyzed sample, independently of the depth of sampling. Thus, the mineralogical index of alteration (MIA) can provide more accurate information about the behavior of major and trace elements in regolith as opposed to unweathered bedrock. It can also aid in establishing a quantitative relationship between intensity of weathering and mobility (leaching or accumulation) of each element in each analyzed sample. At Omai, some major and trace elements that are commonly considered as immobile (ex: TiO{sub 2}, Zr, etc.) during weathering could become mobile in several rock types and cannot be used to calculate the mass and volume balance. In addition, due to higher ''immobile element'' ratios, the

  2. A ground electromagnetic survey used to map sulfides and acid sulfate ground waters at the abandoned Cabin Branch Mine, Prince William Forest Park, northern Virginia gold-pyrite belt

    Science.gov (United States)

    Wynn, Jeffrey C.

    2000-01-01

    INTRODUCTION AND BACKGROUND: Prince William Forest Park is situated at the northeastern end of the Virginia Gold-Pyrite belt northwest of the town of Dumfries, VA. The U. S. Marine Corps Reservation at Quantico borders the park on the west and south, and occupies part of the same watershed. Two abandoned mines are found within the park: the Cabin Branch pyrite mine, a historic source of acid mine drainage, and the Greenwood gold mine, a source of mercury contamination. Both are within the watershed of Quantico Creek (Fig.1). The Cabin Branch mine (also known as the Dumfries mine) lies about 2.4 km northwest of the town of Dumfries. It exploited a 300 meter-long, lens-shaped body of massive sulfide ore hosted by metamorphosed volcanic rocks; during its history over 200,000 tons of ore were extracted and processed locally. The site became part of the National Capitol Region of the National Park Service in 1940 and is currently managed by the National Park Service. In 1995 the National Park Service, in cooperation with the Virginia Department of Mines, Minerals, and Energy reclaimed the Cabin Branch site. The Virginia Gold-Pyrite belt, also known as the central Virginia volcanic-plutonic belt, is host to numerous abandoned metal mines (Pavlides and others, 1982), including the Cabin Branch deposit. The belt itself extends from its northern terminus near Cabin Branch, about 50 km south of Washington, D.C., approximately 175 km to the southwest into central Virginia. It is underlain by metamorphosed volcanic and clastic (non-carbonate) sedimentary rocks, originally deposited approximately 460 million years ago during the Ordovician Period (Horton and others, 1998). Three kinds of deposits are found in the belt: volcanic-associated massive sulfide deposits, low-sulfide quartz-gold vein deposits, and gold placer deposits. The massive sulfide deposits such as Cabin Branch were historically mined for their sulfur, copper, zinc, and lead contents, but also yielded byproduct

  3. Análisis de deformación finita en el Antiforme del Narcea y el Manto de Somiedo, NW de España

    OpenAIRE

    Pastor Galán, Daniel; Gutiérrez Alonso, Gabriel; Mulchrone, Kathleen; Meere, P.

    2008-01-01

    En el orógeno Varisco del NW de Iberia se producen variaciones en la deformación interna delas rocas de forma gradual entre las zonas externas e internas del orógeno. En este estudio se hacaracterizado la deformación interna de las rocas en parte de la Zona Cantábrica (el Manto de Somiedo) yen la transición a la Zona Asturoccidental-Leonesa (el Antiforme del Narcea). Para caracterizar ladeformación interna se ha utilizado una metodología semiautomática de análisis por los métodos Rf/Ø ycentro...

  4. Gold and uranium metallogenesis in the framework of Neo-proterozoic crust growth and differentiation: example of the Mayo-Kebbi Massif (Chad) in the Central Africa Orogenic belt

    International Nuclear Information System (INIS)

    Mbaguedje, Diondoh

    2015-01-01

    The Mayo Kebbi massif located in southwestern Chad between the Congo craton in the South, the West African craton in the west and the Sahara meta-craton to the east exposes a segment of Neo-proterozoic juvenile crust accreted in the Central African orogenic belt during the Pan African orogeny. It consists of two greenstone belts (Zalbi and Goueygoudoum) separated by the May Kebbi calc-alkaline batholith complexes and intruded by calc-alkaline high-K granitic plutons. The whole is covered by Phanerozoic sedimentary formations. The greenstone belts contain sulphide zones hosted mainly by meta-plutonic rocks (granodiorites) and meta-basalts and meta-volcaniclastics. The mineralization comprises pyrite, pyrrhotite, arsenopyrite, chalcopyrite, pentlandite, pentlandite silver, pentlandite cobaltiferous, sphalerite, cobaltite. These sulphides are disseminated, aggregated in form of layers or are filling veins and cracks. The greenstones also contain quartz veins with calcite and chlorite comprising a mineralization made of pyrite, chalcopyrite, galena and gold. Gold is present both as native crystals and as electrum. The high-K calc-alkaline Zabili granitic pluton hosts uranium mineralization related to a superposition of: (1) ductile deformation and metasomatic alteration implying the interaction between magmatic minerals with a Na-rich fluid, of potential magmatic origin, coeval to the main deposition of uranium oxides, followed by (2) brittle deformation and deposition of secondary hydrated uranium silicates involving a Na-Ca-rich fluid. We propose that these uranium mineralizations represent the extreme expression of crustal differentiation as a result of Pan-African reworking of a Neo-proterozoic juvenile crustal segment. (author) [fr

  5. Remote sensing and Aeromagnetic investigations in porphyry copper deposits for identification of areas with high concentration of gold: a case study from the central part of Dehaj-Sarduiyeh belt, Kerman, Iran

    Directory of Open Access Journals (Sweden)

    Mahdieh Hosseinjani Zadeh

    2018-04-01

    Full Text Available Introduction Remote sensing has shown tremendous potential in the identification of alteration zones. The importance of this science for mineral exploration and recognition of alteration zones with lower cost, time, and manpower is confirmed in many studies (Amer et al., 2012; Hosseinjani Zadeh et al., 2014; Tayebi and Tangestani, 2015; Shahriari et al., 2015. Gold is one of the byproducts in most of the porphyry copper deposits (PCDs. Although the gold assay is partly low and reaches between 0.012- 0.38 g/t in these deposits, the high tonnage of copper deposits provides a considerable source of gold which has an important economic value (Kerrich et al., 2000. Extension, intensity of alteration, assays and the type of mineralization vary in different deposits. For instance, many Au-poor porphyry copper deposits in southwest USA, Central Asia, and west of South America are associated with widespread phyllic alteration (Kesler et al., 2002. In addition, there is a positive correlation between gold and magnetite in PCDs (Kesler et al., 2002; Shafiei and Shahabpour, 2008; Sillitoe, 1979. Therefore, aeromagnetic investigation could be useful in identification of these deposits. The aim of this research is discrimination of alteration zones and investigation areas with high concentration of gold through processing of remote sensing and aeromagnetic data. Materials and methods A number of prone areas with different concentrations of gold in Dehaj-Sarduiyeh copper belt including Sar Kuh, Abdar, Meiduk, Sarcheshmeh, Darrehzar, Sara, Iju and Seridune were investigated using the processing of Advanced space borne thermal emission and reflection radiometer (ASTER, and aeromagnetic data. Pre-processing acts such as crosstalk correction and Internal Average Relative Reflection (IARR calibration were implemented on the ASTER data in order to remove noise and acquire surface reflectance. The alteration minerals were discriminated by implementation of

  6. Strata-bound Fe-Co-Cu-Au-Bi-Y-REE deposits of the Idaho Cobalt Belt: Multistage hydrothermal mineralization in a magmatic-related iron oxide copper-gold system

    Science.gov (United States)

    Slack, John F.

    2012-01-01

    Mineralogical and geochemical studies of strata-bound Fe-Co-Cu-Au-Bi-Y-rare-earth element (REE) deposits of the Idaho cobalt belt in east-central Idaho provide evidence of multistage epigenetic mineralization by magmatic-hydrothermal processes in an iron oxide copper-gold (IOCG) system. Deposits of the Idaho cobalt belt comprise three types: (1) strata-bound sulfide lenses in the Blackbird district, which are cobaltite and, less commonly, chalcopyrite rich with locally abundant gold, native bismuth, bismuthinite, xenotime, allanite, monazite, and the Be-rich silicate gadolinite-(Y), with sparse uraninite, stannite, and Bi tellurides, in a gangue of quartz, chlorite, biotite, muscovite, garnet, tourmaline, chloritoid, and/or siderite, with locally abundant fluorapatite or magnetite; (2) discordant tourmalinized breccias in the Blackbird district that in places have concentrations of cobaltite, chalcopyrite, gold, and xenotime; and (3) strata-bound magnetite-rich lenses in the Iron Creek area, which contain cobaltiferous pyrite and locally sparse chalcopyrite or xenotime. Most sulfide-rich deposits in the Blackbird district are enclosed by strata-bound lenses composed mainly of Cl-rich Fe biotite; some deposits have quartz-rich envelopes.Whole-rock analyses of 48 Co- and/or Cu-rich samples show high concentrations of Au (up to 26.8 ppm), Bi (up to 9.16 wt %), Y (up to 0.83 wt %), ∑REEs (up to 2.56 wt %), Ni (up to 6,780 ppm), and Be (up to 1,180 ppm), with locally elevated U (up to 124 ppm) and Sn (up to 133 ppm); Zn and Pb contents are uniformly low (≤821 and ≤61 ppm, respectively). Varimax factor analysis of bulk compositions of these samples reveals geochemically distinct element groupings that reflect statistical associations of monazite, allanite, and xenotime; biotite and gold; detrital minerals; chalcopyrite and sparse stannite; quartz; and cobaltite with sparse selenides and tellurides. Significantly, Cu is statistically separate from Co and As

  7. Gold deposits of the southern Piedmont

    Science.gov (United States)

    Pardee, J.T.; Park, C.F.

    1948-01-01

    This report deals chiefly with the gold mines in the Southern Appalachian gold belt whose workings were accessible at the time of examination, but it also · summarizes available information concerning many mines that were not accessible. Most of the mines lie within a belt, 10 to 100 miles wide, that extends

  8. Zircon U-Pb ages and Hf isotope data from the Kukuluma Terrain of the Geita Greenstone Belt, Tanzania Craton: Implications for stratigraphy, crustal growth and timing of gold mineralization

    Science.gov (United States)

    Kwelwa, S. D.; Sanislav, I. V.; Dirks, P. H. G. M.; Blenkinsop, T.; Kolling, S. L.

    2018-03-01

    The Geita Greenstone Belt is a late Archean greenstone belt located in the Tanzania Craton, trending approximately E-W and can be subdivided into three NW-SE trending terrains: the Kukuluma Terrain to the east, the Central Terrain in the middle and the Nyamullilima Terrain in the west. The Kukuluma Terrain, forms a NW-SE trending zone of complexly deformed sediments, intruded by the Kukuluma Intrusive Complex which, contains an early-syntectonic diorite-monzonite suite and a late-syntectonic granodiorite suite. Three gold deposits (Matandani, Kukuluma and Area 3W) are found along the contact between the Kukuluma Intrusive Complex and the sediments. A crystal tuff layer from the Kukuluma deposits returned an age of 2717 ± 12 Ma which can be used to constrain maximum sedimentation age in the area. Two granodiorite dykes from the same deposit and a small granodiorite intrusion found along a road cut yielded zircon ages of 2667 ± 17 Ma, 2661 ± 16 Ma and 2663 ± 11 Ma respectively. One mineralized granodiorite dyke from the Matandani deposit has an age of 2651 ± 14 Ma which can be used to constrain the maximum age of the gold mineralization in the area. The 2717 Ma crystal tuff has zircon grains with suprachondritic 176Hf/177Hf ratios (0.28108-0.28111 at 2717 Ma) and positive (+1.6 to +2.6) εHf values indicating derivation from juvenile mafic crust. Two of the granodiorite samples have suprachondritic 176Hf/177Hf ratios (avg. 0.28106 and 0.28107 at 2663 and 2651 Ma respectively) and nearly chondritic εHf values (avg. -0.5 and -0.3 respectively). The other two granodiorite samples have chondritic 176Hf/177Hf ratios (avg. 0.28104 and 0.28103 at 2667 and 2661 Ma respectively) and slightly negative εHf values (avg. -1.1 and -1.5 respectively). The new zircon age and isotope data suggest that the igneous activity in the Kukuluma Terrain involves a significant juvenile component and occurred within the 2720 to 2620 Ma period which, is the main period of crustal growth

  9. U-Pb and Pb-Pb study of the Murchison Greenstone Belt and of the Evander gold-bearing basin, South Africa. Implications for the evolution of the Kaapvaal craton

    International Nuclear Information System (INIS)

    Poujol, M.

    1997-01-01

    This study presents new U-Pb and Pb-Pb isotopic data for both the Central Rand Group from the Evander Goldfield and the Murchison Greenstone Belt (Republic of South Africa). The Evander Goldfield, where no previous isotopic data have been derived, is located in the eastern side of the Witwatersrand basin. The oldest age measured is ca. 3180 Ma, while the majority of detritus falls in the range 3050-2850 Ma. New growth of zircon (or isotopic resetting of older detritus) appears to have been associated with deposition of the Ventersdorp lavas at ca. 2.7 Ga. A small proportion of the pyrite, mainly extracted from unaltered sediments in the Kimberley Reef footwall, yields ages that are in excess of the minimum depositional age of the Witwatersrand Basin. Authigenic pyrite, as well as detrital grains from highly altered portions of the Kimberley Reef, define two main events. The Pb signature of the 2370 Ma event is probably associated with burial of the basin by the upper portion of the Transvaal sequence, and suggests circulation of highly radiogenic fluids. Isotopic signatures for the 2020 Ma event are probably related to Bushveld intrusion and/or Vredefort catastrophism, and appear to be associate with a fluid that was less radiogenic. The present study shows a number of new results which support a complex, multi-stage evolution and genesis of the Au-U deposits within the Witwatersrand Basin. The Murchison Greenstone Belt constitutes one of the world's largest antimony producing areas and also hosts gold, as well as volcanogenic massive sulfide Cu-Zn mineralization and emeralds. The goal of this study is to determine the age of the belt as well as the timing of mineralization and, also, to assess the potential role of granitoids in the ore-forming processes. The data identify an episode of greenstone formation between 3.09 Ga and 2.97 Ga. Three main magmatic events are identified at ca. 2.97, 2.82 and 2.68 Ga. Pyrites associated with both Sb-Au and Cu

  10. Radiological survey and assessment of associated activity concentration of the naturally occurring radioactive materials (NORM) in the Migori artisanal gold mining belt of southern Nyanza, Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Odumo, O.B., E-mail: benodumoo@uonbi.ac.k [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya); Mustapha, A.O. [Department of Physics, University of Agriculture, P.M.B. 2240 Abeokuta (Nigeria); Patel, J.P.; Angeyo, H.K. [Department of Physics, University of Nairobi, P.O. Box 30197-00100 Nairobi (Kenya)

    2011-06-15

    A radiological survey and assessment was carried out at selected sites (Osiri, Mikei, Masara and Macalder) in the Migori gold mines of southern Nyanza, Kenya to determine the levels of exposure of the artisanal miners to the naturally occurring radioactive materials (NORM) and dust. The activity concentrations of {sup 40}K and the decay products of {sup 232}Th and {sup 226}Ra were obtained using an innovative method in single channel NaI(Tl) gamma-ray spectrometry. The counts for both the sample and the reference material in a specific window for a particular radionuclide were compared to arrive at the activity concentration of the radionuclide in the sample. Measurement of dust loading at various crushing sites was carried out by trapping the dust particles on a 0.45 {mu}m cellulose acetate filter paper (47 mm diameter) using a vacuum pump. The activity concentration levels range widely 80-413, 12-145 and 21-258 Bq/kg for {sup 40}K, {sup 232}Th and {sup 226}Ra, respectively. The calculated absorbed dose in air range from 16 to 178 nGy/h (with a mean of 42 nGy/h). Dust loading was found to range from 1.3 to 3.7 mg/m{sup 3}. Although the activity concentration of the radionuclides and the calculated annual absorbed dose is below the world's average, the dust level at the mines was relatively high. The results obtained show that the artisanal miners are exposed to various levels of radionuclides and dust and necessary precautions need to be taken.

  11. Seat belt reminders.

    NARCIS (Netherlands)

    2008-01-01

    Seat belts are an effective way of reducing the number or road deaths and severe road injuries in crashes. Seat belt reminders warn car drivers and passengers if the seat belt is not fastened. This can be done by a visual signal or an acoustic signal or by a combination of the two. Seat belt

  12. Belt attachment and system

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abraham D.; Davidson, Erick M.

    2018-03-06

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  13. Synaptic ribbon. Conveyor belt or safety belt?

    Science.gov (United States)

    Parsons, T D; Sterling, P

    2003-02-06

    The synaptic ribbon in neurons that release transmitter via graded potentials has been considered as a conveyor belt that actively moves vesicles toward their release sites. But evidence has accumulated to the contrary, and it now seems plausible that the ribbon serves instead as a safety belt to tether vesicles stably in mutual contact and thus facilitate multivesicular release by compound exocytosis.

  14. Lap belts and three-point belts.

    NARCIS (Netherlands)

    Kampen, L.T.B. van & Edelman, A.

    1975-01-01

    Results of the swov-accident investigation prove that if there are any differences in the effectiveness of lap belts and three-point belts, these are so small that they cannot form a basis for giving preference to one type over the other. Furthermore, in spite of the results of this investigation

  15. Belt Aligning Revisited

    Directory of Open Access Journals (Sweden)

    Yurchenko Vadim

    2017-01-01

    parts of the conveyor, the sides of the belt wear intensively. This results in reducing the life of the belt. The reasons for this phenomenon are well investigated, but the difficulty lies in the fact that they all act simultaneously. The belt misalignment prevention can be carried out in two ways: by minimizing the effect of causes and by aligning the belt. The construction of aligning devices and errors encountered in practice are considered in this paper. Self-aligning roller supports rotational in plan view are recommended as a means of combating the belt misalignment.

  16. Belt drive construction improvement

    Directory of Open Access Journals (Sweden)

    I.Yu. Khomenko

    2012-08-01

    Full Text Available The possibility of the traction capacity increase of the belt drive TRK is examined. This was done for the purpose of air conditioning system of passenger car with double-generator system energy supplying. Belts XPC (made by the German firm «Continental ContiTech» testing were conducted. The results confirmed the possibility of their usage in order to improve belt drive TRK characteristics.

  17. Riding the belt

    Energy Technology Data Exchange (ETDEWEB)

    Potts, A

    1998-04-01

    Recent developments in conveyor systems have focused on accessories rather than the belt itself. Radio frequency identification (RFID) is a technology using transponders embedded in conveyor belts and this is the latest development at the German firm Contitech. The system described in the articles developed with Moers, features transponders for cooling, controlling and monitoring conveyor belts. Other developments mentioned include a JOKI drum motor featuring a fully integrated gearbox and electric motor enclosed in a steel shell, from Interoll; a new scraper cleaning system from Hosch, new steel cord belting from Fenner, a conveying system for Schleenhain lignite opencast mine by FAM Foerdelantigen Magdeburg; new bearings from Nadella (the sales arm of Intersoll-Rand), an anti-shock belt transfer table from Rosta and new caliper disc brakes from GE Industrial.

  18. Validity of maximal isometric knee extension strength measurements obtained via belt-stabilized hand-held dynamometry in healthy adults.

    Science.gov (United States)

    Ushiyama, Naoko; Kurobe, Yasushi; Momose, Kimito

    2017-11-01

    [Purpose] To determine the validity of knee extension muscle strength measurements using belt-stabilized hand-held dynamometry with and without body stabilization compared with the gold standard isokinetic dynamometry in healthy adults. [Subjects and Methods] Twenty-nine healthy adults (mean age, 21.3 years) were included. Study parameters involved right side measurements of maximal isometric knee extension strength obtained using belt-stabilized hand-held dynamometry with and without body stabilization and the gold standard. Measurements were performed in all subjects. [Results] A moderate correlation and fixed bias were found between measurements obtained using belt-stabilized hand-held dynamometry with body stabilization and the gold standard. No significant correlation and proportional bias were found between measurements obtained using belt-stabilized hand-held dynamometry without body stabilization and the gold standard. The strength identified using belt-stabilized hand-held dynamometry with body stabilization may not be commensurate with the maximum strength individuals can generate; however, it reflects such strength. In contrast, the strength identified using belt-stabilized hand-held dynamometry without body stabilization does not reflect the maximum strength. Therefore, a chair should be used to stabilize the body when performing measurements of maximal isometric knee extension strength using belt-stabilized hand-held dynamometry in healthy adults. [Conclusion] Belt-stabilized hand-held dynamometry with body stabilization is more convenient than the gold standard in clinical settings.

  19. Belt conveying of minerals

    Energy Technology Data Exchange (ETDEWEB)

    Stace, L.R.; Yardley, E.D. [University of Nottingham, Nottingham (United Kingdom). School of Civil Engineering

    2008-02-15

    A discussion of the history and economics of conveyor applications sets the scene. Conveyor design is investigated in detail, covering power requirements, belt tensioning, and hardware. Principles regarding construction and joining of belts are outlined and a helpful and practical overview of relevant standards, belt test methods, and issues surrounding standardisation is given. Conveyor belt systems can represent a significant operational hazard, so the authors have set out to highlight the important area of safety, with consideration given to fire/electrical resistance, as well as the interface between personnel and conveyor systems - including nip points and operational issues such as man-riding. Selected case studies illustrate some practical aspects of installation and operation, at Selby mine in the UK and Prosper-Haniel Colliery in Germany and others. 3 apps.

  20. Earth's radiation belts

    International Nuclear Information System (INIS)

    Moslehi Fard, M.

    1984-01-01

    The theory of trapped particles in a magnetic field of approximated dipole is described completely in the first part. Second part contains experimental results. The mechanism of radiation belt source ''albedo neutrons'' and also types of dissipation mechanism about radiation belt is explained. The trapped protons and electrons by radiation belt is discussed and the life-time of trapped particles are presented. Finally the magnetic fields of Moon, Venus, Mars, and Saturn, measured by passengers Mariner 4,10 and pioneer 10,11 are indicated. The experimental and theoretical results for the explanation of trapped plasma around the earth which is looked like two internal and external belt have almost good correspondence

  1. Principal types of precambrian uranium-gold deposits and their metallogenetic characteristics in China

    International Nuclear Information System (INIS)

    Liang Liang; Zhong Zhiyun.

    1988-01-01

    Principal types of Precambrian uranium-gold deposits are follows: paleo-conglomerate uranium-deposit, stratified or strata-bound uranium-gold deposit, unconformity-related uranium deposit (no or seldem gold) and greenstone gold deposit. The main types of gold deposits in China is greenstone one which is characterized by later age, high grade metamorphism and a large time difference between diagenesis of host rocks and gold metallogenesis. Gold deposits are spatially distributed in the uplift area, whereas uranium deposits are distributed in the downfaulted belt. Furthermore, both uranium and gold deposits are controlled by regional fractures

  2. Belt conveyor apparatus

    Science.gov (United States)

    Oakley, David J.; Bogart, Rex L.

    1987-01-01

    A belt conveyor apparatus according to this invention defines a conveyance path including a first pulley and at least a second pulley. An endless belt member is adapted for continuous travel about the pulleys and comprises a lower portion which engages the pulleys and an integral upper portion adapted to receive objects therein at a first location on said conveyance path and transport the objects to a second location for discharge. The upper belt portion includes an opposed pair of longitudinally disposed crest-like members, biased towards each other in a substantially abutting relationship. The crest-like members define therebetween a continuous, normally biased closed, channel along the upper belt portion. Means are disposed at the first and second locations and operatively associated with the belt member for urging the normally biased together crest-like members apart in order to provide access to the continuous channel whereby objects can be received into, or discharged from the channel. Motors are in communication with the conveyance path for effecting the travel of the endless belt member about the conveyance path. The conveyance path can be configured to include travel through two or more elevations and one or more directional changes in order to convey objects above, below and/or around existing structures.

  3. Gold prices

    OpenAIRE

    Joseph G. Haubrich

    1998-01-01

    The price of gold commands attention because it serves as an indicator of general price stability or inflation. But gold is also a commodity, used in jewelry and by industry, so demand and supply affect its pricing and need to be considered when gold is a factor in monetary policy decisions.

  4. New developments of belt conveyor systems; Inclined belt systems, vertical pipe elevators, vibration belts, oscillating tubes

    Energy Technology Data Exchange (ETDEWEB)

    Bahke, E.A. (Universitaet Karlsruhe, Karlsruhe (Germany, F.R.). Inst. fuer Foerdertechnik)

    1991-03-01

    Factors that have influenced the design of belt conveyor systems are discussed - these include strength and shaping. Belt conveyor systems for inclined, steep-angle and vertical conveying are described and comparison made between cable belt and steel cord belt conveyors used in coal mines. Hose-belt or tube conveyors such as are used in the PWH/Conti-Rollgurt Conveyor System for feeding boilers in German coal fired power stations are mentioned and advantages of the pipe-belt conveyor for vertical transport discussed. Design of the vibratory conveyor for transporting solids upwards by pulses is described. 29 refs., 19 figs., 2 tabs.

  5. Gold deposit styles and placer gold characterisation in northern and east-central Madagascar

    Science.gov (United States)

    Pitfield, Peter E. J; Styles, Michael T.; Taylor, Cliff D.; Key, Roger M.; Bauer,; Ralison, A

    2009-01-01

    Microchemical characterisation of bedrock and placer gold grains from six gold districts within the Archaean domains and intervening Neoproterozoic Anaboriana-Manampotsy belt of northern and east-central Madagascar show few opaque inclusions (e.g pyrrhotite, Bi tellurides) but wide range of Ag contents (40wt%). Some districts exhibit multiple source populations of grains. The ‘greenstone belt’ terranes have an orogenic gold signature locally with an intrusion-related to epithermal overprint. Proterozoic metasediments with felsic to ultramafic bodies yield dominantly intrusion-related gold. A high proportion of secondary gold (<0.5wt% Ag) is related to recycling of paleoplacers and erosion of post-Gondwana planation surfaces and indicates that some mesothermal gold systems were already partially to wholly removed by erosion by the PermoTriassic.

  6. Coal belt options

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-03-15

    Whether moving coal long distances overland or short distances in-plant, belt conveyors will always be in demand. The article reports on recent systems developments and applications by Beumer, Horizon Conveyor Equipment, Conveyor Dynamics, Doppelmayr Transport Technology, Enclosed Bulk Systems, ContiTech and Bateman Engineered Technologies. 2 photos.

  7. Metal mobility during metamorphism and formation of orogenic gold deposits: Insights from the Dalradian of Scotland

    OpenAIRE

    Engström, Adam

    2013-01-01

    Orogenic gold deposits occur within metamorphic belts throughout the world and have through time represented the source for over 25% of the world’s gold production. Although orogenic gold deposits are of great economic importance, controversies exist on the subject of fluid and metal sources and there have been few studies of gold´s distribution and mobility outside of large economic deposits. Research made by Pitcairn et al. (2006), on the Mesozoic Otago and Alpine schists of New Zealand, ob...

  8. Rb-Sr, K-Ar, and stable isotope evidence for the ages and sources of fluid components of gold-bearing quartz veins in the northern Sierra Nevada foothills metamorphic belt, California

    Science.gov (United States)

    Böhlke, John Karl; Kistler, R. W.

    1986-01-01

    Gold-bearing quartz veins occur in and near major fault zones in deformed oceanic and island-arc rocks west of the main outcrop of the Sierra Nevada composite batholith. Veins typically occupy minor reverse faults that crosscut blueschist to amphibolite-grade metamorphic rocks whose metamorphic ages range from early Paleozoic to Jurassic. Vein micas and carbonate-quartz-mica assemblages that formed by hydrothermal metasomatism of ultramafic wall rocks in the Alleghany, Grass Valley, Washington, and Mother Lode districts yield concordant K-Ar and Rb-Sr ages. The dated veins are significantly younger than prograde metamorphism, penetrative deformation, and accretion of their host rocks to the continental margin. New and previously published mineralization ages from 13 localities in the Sierra foothills range from about 140 to 110 m.y. ago, with mean and median between 120 and 115 m.y. The age relations suggest that mineralizing fluids were set in motion by deep magmatic activity related to the resumption of east-dipping subduction along the western margin of North America following the Late Jurassic Nevadan collision event.CO 2 -bearing fluids responsible for metasomatism and much of the vein mica, carbonate, albite, and quartz deposition in several northern mines were isotopically heavy (delta 18 O [asymp] 8-14ppm; delta D between about -10 and -50ppm) and do not resemble seawater, magmatic, or meteoric waters. Metasomatic and vein-filling mica, dolomite, magnesite, and quartz in altered ultramafic rocks generally formed from fluids with similar Sr and O isotope ratios at a given locality. Consistent quartz-mica delta 18 O fractionations (delta 18 O (sub Q-M) = 4.5-4.9ppm) from various localities imply uniform equilibration temperatures, probably between 300 degrees and 350 degrees C. On a local (mine) scale, fluids responsible for both carbonate alteration of mafic and ultramafic wall rocks and albitic alteration of felsic and pelitic rocks had similar Sr isotope

  9. Deconstructing the conveyor belt.

    Science.gov (United States)

    Lozier, M Susan

    2010-06-18

    For the past several decades, oceanographers have embraced the dominant paradigm that the ocean's meridional overturning circulation operates like a conveyor belt, transporting cold waters equatorward at depth and warm waters poleward at the surface. Within this paradigm, the conveyor, driven by changes in deepwater production at high latitudes, moves deep waters and their attendant properties continuously along western boundary currents and returns surface waters unimpeded to deepwater formation sites. A number of studies conducted over the past few years have challenged this paradigm by revealing the vital role of the ocean's eddy and wind fields in establishing the structure and variability of the ocean's overturning. Here, we review those studies and discuss how they have collectively changed our view of the simple conveyor-belt model.

  10. Paired Magmatic-Metallogenic Belts in Myanmar - an Andean Analogue?

    Science.gov (United States)

    Gardiner, Nicholas; Robb, Laurence; Searle, Michael; Morley, Christopher

    2015-04-01

    Myanmar (Burma) is richly endowed in precious and base metals, having one of the most diverse collections of natural resources in SE Asia. Its geological history is dominated by the staged closing of Tethys and the suturing of Gondwana-derived continental fragments onto the South China craton during the Mesozoic-Cenozoic. The country is located at a crucial geologic juncture where the main convergent Tethyan collision zone swings south around the Namche Barwa Eastern Himalayan syntaxis. However, despite recent work, the geological and geodynamic history of Myanmar remains enigmatic. Plate margin processes, magmatism, metasomatism and the genesis of mineral deposits are intricately linked, and there has long been recognized a relationship between the distribution of certain mineral deposit types, and the tectonic settings which favour their genesis. A better knowledge of the regional tectonic evolution of a potential exploration jurisdiction is therefore crucial to understanding its minerals prospectivity. This strong association between tectonics and mineralization can equally be applied in reverse. By mapping out the spatial, and temporal, distribution of presumed co-genetic mineral deposits, coupled with an understanding of their collective metallogenetic origin, a better appreciation of the tectonic evolution of a terrane may be elucidated. Identification and categorization of metallotects within a geodynamically-evolving terrane thus provides a complimentary tool to other methodologies (e.g. geochemical, geochronological, structural, geophysical, stratigraphical), for determining the tectonic history and inferred geodynamic setting of that terrane through time. Myanmar is one such study area where this approach can be undertaken. Here are found two near-parallel magmatic belts, which together contain a significant proportion of that country's mineral wealth of tin, tungsten, copper, gold and silver. Although only a few 100 km's apart, these belts exhibit a

  11. Gold Returns

    OpenAIRE

    Robert J. Barro; Sanjay P. Misra

    2013-01-01

    From 1836 to 2011, the average real rate of price change for gold in the United States is 1.1% per year and the standard deviation is 13.1%, implying a one-standard-deviation confidence band for the mean of (0.1%, 2.1%). The covariances of gold's real rate of price change with consumption and GDP growth rates are small and statistically insignificantly different from zero. These negligible covariances suggest that gold's expected real rate of return--which includes an unobserved dividend yiel...

  12. Lap belt injuries in children.

    LENUS (Irish Health Repository)

    McGrath, N

    2010-07-01

    The use of adult seat belts without booster seats in young children may lead to severe abdominal, lumbar or cervical spine and head and neck injuries. We describe four characteristic cases of lap belt injuries presenting to a tertiary children\\'s hospital over the past year in addition to a review of the current literature. These four cases of spinal cord injury, resulting in significant long-term morbidity in the two survivors and death in one child, arose as a result of lap belt injury. These complex injuries are caused by rapid deceleration characteristic of high impact crashes, resulting in sudden flexion of the upper body around the fixed lap belt, and consequent compression of the abdominal viscera between the lap belt and spine. This report highlights the dangers of using lap belts only without shoulder straps. Age-appropriate child restraint in cars will prevent these injuries.

  13. Belt for picking up liquids

    Energy Technology Data Exchange (ETDEWEB)

    Sewell, R B.H.; Nelson, S P

    1973-05-18

    This belt for picking up liquids consists of a layer of strong material, e.g., coarse cloth, sewed on at least one layer of absorbing material, e.g., sponge cloth, the stitching being disposed along chevrons with their apexes along the central axis of the belt; the edges do not contain any other marks. This arrangement facilitates the expulsion of the absorbed liquid when the belt passes between compression rollers.

  14. Gold monetization and gold discipline

    OpenAIRE

    Robert P. Flood; Peter M. Garber

    1981-01-01

    The paper is a study of the price level and relative price effects of a policy to monetize gold and fix its price at a given future time and at the then prevailing nominal price. Price movements are analyzed both during the transition to the gold standard and during the post-monetization period. The paper also explores the adjustments to fiat money which are necessary to ensure that this type of gold monetization is non-inflationary. Finally, some conditions which produce a run on the governm...

  15. SLH Timing Belt Powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abe

    2014-04-09

    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  16. Belt of Yotvings. Radioecology

    International Nuclear Information System (INIS)

    Mazheika, J.; Petroshius, R.; Strzelecki, R.; Wolkovitcz, S.; Lewandowski, P.

    1997-01-01

    Full text: The map of gamma radiation dose of 'Belt of Yotvings' area displays the summarized gamma radiation coming from natural radionuclides of 238 U, 232 Th, 40 K and from cesium isotopes 137 Cs, 134 Cs, artificially supplied into the environment after the Chernobyl disaster. The average value of gamma radiation dose for 'Belt of Yotvings' area is 44.2 n Gy/h, with a distinct regional differentiation. The content of uranium varies from 0 to 4.5 g/t, with the average value of about 1.4 g/t. Thorium content varies from 0 to 10.3 g/t, with the average value of 4.3 g/t. Potassium content varies from 0.1 up to 2.5 %, with the average value of 1.2 %. The concentration of caesium radioisotopes reaches up to 11.6 kBq/m 2 , the average value being 3.8 kBq/m 2 . Radon concentration in soil air has been determined in 55 sites (83 analyses). Radon concentration has been noticed in volumes from trace amounts up to 55 kBq/m3.The radioecological mapping has documented that the highest concentrations of natural radioisotopes and, correspondingly, the highest total gamma radiation dose were observed in the northeastern part of the area studied, which is covered by clay-silty glaciolacustrine deposits. Slightly lower values are typical for the whole northwestern part of 'Belt of Yotvings'. Very low contents of radioactive elements and low total radiation doses are typical for eolian and sandur sands, occurring south-eastward from the line Augustow-Veisiejai. The Chernobyl NPP accident polluted the studied region with artificial cesium radioisotopes un significantly. The concentrations are low and they involve no radioecological hazard. The investigation of radon concentration in soil air have revealed several places affected by high radon emanation. These places should be studied in a more detailed way

  17. Simple fabrication of gold nanobelts and patterns.

    Directory of Open Access Journals (Sweden)

    Renyun Zhang

    Full Text Available Gold nanobelts are of interest in several areas; however, there are only few methods available to produce these belts. We report here on a simple evaporation induced self-assembly (EISA method to produce porous gold nanobelts with dimensions that scale across nanometer (thickness ∼80 nm and micrometer (width ∼20 µm, to decimeter (length ∼0.15 m. The gold nanobelts are well packed on the beaker wall and can be easily made to float on the surface of the solution for depositing onto other substrates. Microscopy showed that gold nanobelts had a different structure on the two sides of the belt; the density of gold nanowires on one side was greater than on the other side. Electrical measurements showed that these nanobelts were sensitive to compressive or tensile forces, indicating a potential use as a strain sensor. The patterned nanobelts were further used as a template to grow ZnO nanowires for potential use in applications such as piezo-electronics.

  18. Radiation Belt Test Model

    Science.gov (United States)

    Freeman, John W.

    2000-10-01

    Rice University has developed a dynamic model of the Earth's radiation belts based on real-time data driven boundary conditions and full adiabaticity. The Radiation Belt Test Model (RBTM) successfully replicates the major features of storm-time behavior of energetic electrons: sudden commencement induced main phase dropout and recovery phase enhancement. It is the only known model to accomplish the latter. The RBTM shows the extent to which new energetic electrons introduced to the magnetosphere near the geostationary orbit drift inward due to relaxation of the magnetic field. It also shows the effects of substorm related rapid motion of magnetotail field lines for which the 3rd adiabatic invariant is violated. The radial extent of this violation is seen to be sharply delineated to a region outside of 5Re, although this distance is determined by the Hilmer-Voigt magnetic field model used by the RBTM. The RBTM appears to provide an excellent platform on which to build parameterized refinements to compensate for unknown acceleration processes inside 5Re where adiabaticity is seen to hold. Moreover, built within the framework of the MSFM, it offers the prospect of an operational forecast model for MeV electrons.

  19. Geography of the asteroid belt

    Science.gov (United States)

    Zellner, B. H.

    1978-01-01

    The CSM classification serves as the starting point on the geography of the asteroid belt. Raw data on asteroid types are corrected for observational biases (against dark objects, for instance) to derive the distribution of types throughout the belt. Recent work on family members indicates that dynamical families have a true physical relationship, presumably indicating common origin in the breakup of a parent asteroid.

  20. Gold Museum

    OpenAIRE

    Efraín Sánchez Cabra

    2003-01-01

    On 22 december 1939, the Banco de la República, the Central Bank of Colombia, purchased a 23.5 centimetres high pre-Columbian gold arte fact weighing 777·7 grams that was to become the Gold M useum's foundation stone. Described as a Quimbaya poporo, it is a masterpiece of pre-Hispanic goldwork, an object of beauty whose brightly burnished body and neck, crowned with four sphere-like or naments, rest on an exquisite cast metal tiligree base and which seems to ftoat in a space of its own. The b...

  1. Green Gold

    International Nuclear Information System (INIS)

    Salamandra Martinez, Carlos

    2004-01-01

    The main purpose of this work is to offer a general panoramic of the processes or experiences pilot that are carried out in the Project Green Gold, as strategy of environmental sustainability and organizational invigoration in Choco, especially in the 12 communities of the municipalities of Tado and Condoto. It is also sought to offer a minimum of information on the techniques of handmade production and to show the possibilities to carry out in a rational way the use and use of the natural resources. The Project Green Gold is carried out by the Corporation Green Gold (COV) and co-financed with resources of international and national character, the intervention of the financial resources it achievement mainly for the use of clean processes in the extraction stages and metals benefit. The project is centered primarily in the absence of use of products or toxic substances as the mercury, fair trade, organizational invigoration, execution of 11 approaches and certification of the metals Gold and Platinum. The COV, it has come executing the proposal from the year 2001 with the premise of contributing to the balance between the rational exploitation of the natural resources and the conservation of the environment in the Choco. In the project they are used technical handmade characteristic of the region framed inside the mining activity and production activities are diversified in the productive family units. Those producing with the support of entities of juridical character, specify the necessary game rules for the extraction and products commercialization

  2. AUTOMATION OF CONVEYOR BELT TRANSPORT

    Directory of Open Access Journals (Sweden)

    Nenad Marinović

    1990-12-01

    Full Text Available Belt conveyor transport, although one of the most economical mining transport system, introduce many problems to mantain the continuity of the operation. Every stop causes economical loses. Optimal operation require correct tension of the belt, correct belt position and velocity and faultless rolls, which are together input conditions for automation. Detection and position selection of the faults are essential for safety to eliminate fire hazard and for efficient maintenance. Detection and location of idler roll faults are still open problem and up to now not solved successfully (the paper is published in Croatian.

  3. Investigation of a new type charging belt

    International Nuclear Information System (INIS)

    Jones, N.L.

    1994-01-01

    There are many desirable characteristics for an electrostatic accelerator charging belt. An attempt has been made to find a belt that improves on these properties over the stock belt. Results of the search, procurement, and 1,500 hours of operational experience with a substantially different belt are reported

  4. 30 CFR 75.1731 - Maintenance of belt conveyors and belt conveyor entries.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Maintenance of belt conveyors and belt conveyor....1731 Maintenance of belt conveyors and belt conveyor entries. (a) Damaged rollers, or other damaged belt conveyor components, which pose a fire hazard must be immediately repaired or replaced. All other...

  5. Chaos on the conveyor belt.

    Science.gov (United States)

    Sándor, Bulcsú; Járai-Szabó, Ferenc; Tél, Tamás; Néda, Zoltán

    2013-04-01

    The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by a spring to an external static point and, due to the dragging effect of the belt, the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can be achieved only by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic, dynamics and phase transition-like behavior. Noise-induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks (around five).

  6. Mobile belt conveyor

    OpenAIRE

    Tenora, Jiří

    2017-01-01

    Cílem bakalářské práce je návrh pásového dopravníku pro přepravu drobného kameniva, zeminy a drobné stavební sutě s dopravním výkonem 60 t/h, výškovým rozdílem 3,5 m a vzdáleností mezi osami bubnů 8 m. Tato práce obsahuje také popis základních částí pásového dopravníku, funkční výpočty podle normy ČSN ISO 5048, návrh hlavních rozměrů dopravníku a pohonu. Celá práce se skládá z technické zprávy a výkresové dokumentace. The aim of this word is to design belt conveyor to transport tiny aggreg...

  7. Determination of gold in gold ores

    International Nuclear Information System (INIS)

    Keedy, C.R.; Parson, L.; Shen, J.

    1989-01-01

    The gold content of placer gold flakes and gold bearing ores was determined by instrumental and radiochemical neutron activation analysis, respectively. It was discovered that significant errors result in the instrumental method for gold flakes as small as 10 mg due to sample self-absorption of neutrons during irradiation. Reliable results were obtained for both ore samples and gold flakes by dissolving the samples in aqua regia prior to irradiation. (author) 7 refs.; 3 tabs

  8. Horizontal-belt filtration at Randfontein Estates Mine

    International Nuclear Information System (INIS)

    Blendulf, K.A.G.; Everett, D.J.

    1979-01-01

    The paper describes tests on horizontal-belt filters for the filtration of gold and uranium. The promising results led to the installation of 17 such filters (ten of them 120 m 2 in size) in the mine's metallurgical plants, and their operation is discussed. Although several problems were encountered both in operation and maintenance, it is concluded that, with correct operation and suitable filter cloths, exceptionally good metallurgical recoveries can be achieved at filtration rates twice to three times higher than those on rotary filters [af

  9. Belt conveyors for bulk materials. 6th ed.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The 16 chapters are entitled: Belt conveyor general applications economics; Design considerations; Characteristics and conveyability of bulk materials; Capacities, belt widths and speeds; Belt conveyor idlers; Belt tension and power engineering; Belt selection; Pulleys and shafts; Curves; Steep angle conveying; Belt cleaners and accessories; Transfer points; Conveyor motor drives and controls; Operation, maintenance and safety; Belt takeups; and Emerging technologies. 6 apps.

  10. Effectiveness of Ford's belt reminder system in increasing seat belt use

    OpenAIRE

    Williams, A; Wells, J; Farmer, C

    2002-01-01

    Objectives: The study investigated the effectiveness in increasing seat belt use of Ford's belt reminder system, a supplementary system that provides intermittent flashing lights and chimes for five minutes if drivers are not belted.

  11. The auriferous placer at Mount Robert, Pietersburg Greenstone belt

    International Nuclear Information System (INIS)

    Saager, R.; Muff, R.

    1986-01-01

    The Mount Robert gold placer near Potgietersrus occurs in coarse, matrix-supported conglomerates of the Uitkyk Formation within the Pietersburg greenstone belt. Sedimentological and mineralogical investigations indicate that the conglomerates and the ore minerals were derived from a greenstone provenance, and that they were deposited in a braided river environment within a rapidly subsiding trough. Lack of sedimentological concentration of the heavy minerals is considered to be the main reason for the low and erratic gold grades encountered (usually below 1 g/t) and, thus, the failure of all past mining ventures. The mineralogical composition of the Mount Robert ore closely resembles that of the Witwatersrand deposits. However, uraninite is absent, probably as a result of its complete removal by weathering processes. Remaining small uranium concentrations can still be detected within the conglomerates where they occur associated with grains of carbonaceous matter, leucoxene aggregates, and secondary iron-hydroxides. U3O8 values found in the conglomerates are given

  12. Enclosed belts in the ascendancy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-03-15

    Although there will always be a place for traditional overland belt conveyors, enclosed belt systems are increasingly being specified where environmental protection assumes high priority or where there is a need to protect material from the weather. The article reports on recent conveyor projects such as: an MRC cable Belt in a 6.4 km system to carry coal in the Appalachian Mountains; a $40 m contract awarded to FL Smidth to supply an integrated coal handling system to LILIAMA in Vietnam and other contracts to handle coal for India's Coastal Gujarat Power; and a contract awarded to Bateman Engineered Technologies to supply a 7 km Japan Pipe Conveyor for a coal power station in Brazil. 3 photos.

  13. 30 CFR 77.1107 - Belt conveyors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Belt conveyors. 77.1107 Section 77.1107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY... § 77.1107 Belt conveyors. Belt conveyors in locations where fire would create a hazard to personnel...

  14. Grinding Glass Disks On A Belt Sander

    Science.gov (United States)

    Lyons, James J., III

    1995-01-01

    Small machine attached to table-top belt sander makes possible to use belt sander to grind glass disk quickly to specified diameter within tolerance of about plus or minus 0.002 in. Intended to be used in place of production-shop glass grinder. Held on driveshaft by vacuum, glass disk rotated while periphery ground by continuous sanding belt.

  15. 36 CFR 4.15 - Safety belts.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Safety belts. 4.15 Section 4... TRAFFIC SAFETY § 4.15 Safety belts. (a) Each operator and passenger occupying any seating position of a motor vehicle in a park area will have the safety belt or child restraint system properly fastened at...

  16. 14 CFR 31.63 - Safety belts.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Safety belts. 31.63 Section 31.63 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: MANNED FREE BALLOONS Design Construction § 31.63 Safety belts. (a) There must be a safety belt...

  17. 14 CFR 27.1413 - Safety belts.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Safety belts. 27.1413 Section 27.1413 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Safety Equipment § 27.1413 Safety belts. Each safety belt...

  18. 46 CFR 169.723 - Safety belts.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Safety belts. 169.723 Section 169.723 Shipping COAST... Control, Miscellaneous Systems, and Equipment § 169.723 Safety belts. Each vessel must carry a harness type safety belt conforming to Offshore Racing Council (ORC) standards for each person on watch or...

  19. Uranium deposits of the Asian sector of Pacific ocean ore belt

    International Nuclear Information System (INIS)

    Kazanskij, V.I.

    1995-01-01

    Brief description of three basic types of uranium ore deposits in the Asian sector of the Pacific Ocean ore belt, namely uranium-molybdenum vein deposits in the continental volcanic depressions, proper uranium-molybdenum vein deposits in the mesozoic granites and gold-brannerite deposits of the rejuvenated early-proterosoic fractures is given. Schemes of various deposits are presented, petrological and isotope data (K-Ar method) are considered and petro- and oregenesis are analyzed. refs., 9 figs

  20. Conveyor belt nuclear weighing machine

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    In many industries the flow of materials on conveyor belts must be measured and controlled. Electromechanical weighing devices have high accuracy but are complicated and expensive to install and maintain. For many applications the nuclear weighing machine has sufficient accuracy but is considerably simpler, cheaper and more robust and is easier to maintain. The rating and performance of a gamma ray balance on the mar ket are detailed. (P.G.R.)

  1. ∼2.5 Ga late cratonisation events in Dharwar craton: insights from the gold mineralisation ages

    International Nuclear Information System (INIS)

    Srinivasa Sarma, D.; Ram Mohan, M.; McNaughton, Neal

    2013-01-01

    The history of volcanism, granitic magmatism, and gold mineralization is defined by U-Pb geochronology of magmatic zircons and hydrothermal monazite and xenotime respectively. The felsic volcanic host rocks from Hutti greenstone belt have a U-Pb zircon age of 258 ±7 Ma, about 40 m.y. older than the age of gold mineralization at 2547±10 Ma determined from hydrothermal monazite in the Hutti gold deposit. The syntectonic Kavital granitoid in the Hutti greenstone belt has a U-Pb zircon age of 2545±7 Ma, which overlaps with the timing of gold deposition and is consistent with structural interpretations. Zircon U-Pb ages for a felsic volcanic rock (2,588±10 Ma) and an intrusive granite (e''2,555±6 Ma) in the Gadag greenstone belt in the Western Dharwar Craton. In situ U-Pb dating of monazite and xenotime in gold reefs of the Gadag (2,522±6 Ma) and Ajjanahalli (2,520±9 Ma) gold deposits reveal a previously undated episode of gold mineralization at 2.52 Ga, substantially younger than the 2.55 Ga Hutti deposit in the eastern Dharwar Craton. The Hutti, Gadag and Ajjanahalli gold geochronology suggests that gold mineralization occurred throughout the Dharwar craton some 80 to 120 m.y. later than the major peak of Late Archean world-class orogenic gold mineralization in most other Archean cratons. Although gold mineralization across the craton postdates most of the magmatic activity and metamorphism at upper crustal levels, widespread thermal reworking of the lower middle crust, involving partial melting, metamorphism, and lower crustal granitoid intrusion, occurred concurrently with gold mineralization. It is likely that the large-scale hydrothermal fluid flow that produced widespread gold deposition was also part of this tectono-thermal event during the final stages of cratonization of the Dharwar Craton in southern India. (author)

  2. Synchronous and Cogged Fan Belt Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, Dylan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dean, Jesse [National Renewable Energy Lab. (NREL), Golden, CO (United States); Acosta, Jason [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-02-01

    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  3. Belt technology stretches conveyors' coverage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    With China the leading growth engine in the conveyor market, leading belt manufacturers are establishing local manufacturing plants to boost their presence. Fenner is planning to almost triple production capacity over the next three years, with a third of its investment in China. Shanxi-Phoenix Conveyor Belt Systems is a joint venture between Phoenix Conveyor Belt Systems GmbH, now part of ContiTech Ag, and its Chinese partners Lu An Mining Group Co. Ltd. and Jingcheng Anthracite Group Co. Ltd. It manufacturers steel cable belts, PVC and multi-ply belts for coal mines and power plants. Recent belt designs by FennerEurope and Metso Minerals are reported. 2 photos.

  4. Frontiers in Gold Chemistry

    OpenAIRE

    Ahmed A. Mohamed

    2015-01-01

    Basic chemistry of gold tells us that it can bond to sulfur, phosphorous, nitrogen, and oxygen donor ligands. The Frontiers in Gold Chemistry Special Issue covers gold complexes bonded to the different donors and their fascinating applications. This issue covers both basic chemistry studies of gold complexes and their contemporary applications in medicine, materials chemistry, and optical sensors. There is a strong belief that aurophilicity plays a major role in the unending applications of g...

  5. Belt Conveyor Dynamic Characteristics and Influential Factors

    Directory of Open Access Journals (Sweden)

    Junxia Li

    2018-01-01

    Full Text Available This paper uses the Kelvin-Voigt viscoelastic model to establish the continuous dynamic equations for tail hammer tension belt conveyors. The viscoelastic continuity equations are solved using the generalized coordinate method. We analyze various factors influencing longitudinal vibration of the belt conveyor by simulation and propose a control strategy to limit the vibration. The proposed approach and control strategy were verified by several experimental researches and cases. The proposed approach provides improved accuracy for dynamic design of belt conveyors.

  6. Gold in plants

    International Nuclear Information System (INIS)

    Girling, C.A.; Peterson, P.J.

    1980-01-01

    Many plants have the ability to take up gold from the soil and to accumulate it in their tisssue. Advances have been made in understanding these processes to the point where their exploitation in the field of prospecting for gold appears practically feasible. Neutron activation analysis is used for the determination of the small quantities of gold in plants

  7. Drive alive: teen seat belt survey program.

    Science.gov (United States)

    Burkett, Katie M; Davidson, Steve; Cotton, Carol; Barlament, James; Loftin, Laurel; Stephens, James; Dunbar, Martin; Butterfield, Ryan

    2010-08-01

    To increase teen seat belt use among drivers at a rural high school by implementing the Drive Alive Pilot Program (DAPP), a theory-driven intervention built on highway safety best practices. The first component of the program was 20 observational teen seat belt surveys conducted by volunteer students in a high school parking lot over a 38-month period before and after the month-long intervention. The survey results were published in the newspaper. The second component was the use of incentives, such as gift cards, to promote teen seat belt use. The third component involved disincentives, such as increased police patrol and school policies. The fourth component was a programmatic intervention that focused on education and media coverage of the DAPP program. Eleven pre-intervention surveys and nine post-intervention surveys were conducted before and after the intervention. The pre- and post-intervention seat belt usage showed significant differences (p<0.0001). The average pre-intervention seat belt usage rate was 51.2%, while the average post-intervention rate was 74.5%. This represents a percentage point increase of 23.3 in seat belt use after the DAPP intervention. Based on seat belt observational surveys, the DAPP was effective in increasing seat belt use among rural high school teenagers. Utilizing a theory-based program that builds on existing best practices can increase the observed seat belt usage among rural high school students.

  8. Conveyor belt weigher using a nuclear technique

    International Nuclear Information System (INIS)

    Magal, B.S.

    1976-01-01

    Principles of operation of different types of continuous conveyor belt weighing machines developed for use in factories for bulk weighing of material on conveyor belts without interupting the material flow, are briefly mentioned. The design of nuclear weighing scale making use of the radiation absorption property of the material used is described in detail. The radiation source, choice of the source, detector and geometry of such a weighing scale are discussed. The nucleonic belt weigher is compared with the gravimetric belt weigher system. The advantages of the nuclear system are pointed out. The assembly drawing of the electronics, calibration procedure and performance evaluation are given. (A.K.)

  9. Continuous Mass Measurement on Conveyor Belt

    Science.gov (United States)

    Tomobe, Yuki; Tasaki, Ryosuke; Yamazaki, Takanori; Ohnishi, Hideo; Kobayashi, Masaaki; Kurosu, Shigeru

    The continuous mass measurement of packages on a conveyor belt will become greatly important. In the mass measurement, the sequence of products is generally random. An interesting possibility of raising throughput of the conveyor line without increasing the conveyor belt speed is offered by the use of two or three conveyor belt scales (called a multi-stage conveyor belt scale). The multi-stage conveyor belt scale can be created which will adjust the conveyor belt length to the product length. The conveyor belt scale usually has maximum capacities of less than 80kg and 140cm, and achieves measuring rates of more than 150 packages per minute and more. The output signals from the conveyor belt scale are always contaminated with noises due to vibrations of the conveyor and the product to be measured in motion. In this paper an employed digital filter is of Finite Impulse Response (FIR) type designed under the consideration on the dynamics of the conveyor system. The experimental results on the conveyor belt scale suggest that the filtering algorithms are effective enough to practical applications to some extent.

  10. Condition-Based Conveyor Belt Replacement Strategy in Lignite Mines with Random Belt Deterioration

    Science.gov (United States)

    Blazej, Ryszard; Jurdziak, Leszek

    2017-12-01

    In Polish lignite surface mines, condition-based belt replacement strategies are applied in order to assure profitable refurbishment of worn out belts performed by external firms specializing in belt maintenance. In two of three lignite mines, staff asses belt condition subjectively during visual inspections. Only one mine applies specialized diagnostic device (HRDS) allowing objective magnetic evaluation of belt core condition in order to choose the most profitable moment for the dismantling of worn out belt segments from conveyors and sending them to the maintenance firm which provides their refurbishment. This article describes the advantages of a new diagnostic device called DiagBelt. It was developed at the Faculty of Geoengineering, Mining and Geology, Wroclaw University of Science and Technology. Economic gains from its application are calculated for the lignite mine and for the belt maintenance firm, taking into account random life (durability) of new and reconditioned belts (after the 1st and the 2nd refurbishment). Recursive calculations for following years allow the estimation of the length and costs of replaced, reconditioned and purchased belts on an annual basis, while the use of the Monte Carlo method allows the estimation of their variability caused by random deterioration of belts. Savings are obtained due to better selection of moments (times) for the replacement of belt segments and die to the possibility to qualify worn out belts for refurbishment without the need to remove their covers. In effect, increased belt durability and lowered share of waste belts (which were not qualified for reconditioning) create savings which can quickly cover expenditures on new diagnostic tools and regular belt inspections in the mine.

  11. Brusque belt: a monocyclic evolution ?

    International Nuclear Information System (INIS)

    Basei, M.A.S.

    1990-01-01

    This paper discusses the radiometric data for the Brusque Belt (SC) where Rb-Sr isochrons, U-Pb in zircons, K-Ar in minerals and whole rock Sm-Nd model ages are available. The analysis of these results reveals two main groups, without intermediate values. The first, 500 to 800Ma., is related to magmatic and metamorphic ages and the second, 1600-2000Ma begin with the (probably) sedimentation age. A monociclic evolution is proposed, but with uncertanties in the age of the first metamorphic phase. (author)

  12. Fabrication and Operation of a Nano-Optical Conveyor Belt.

    Science.gov (United States)

    Ryan, Jason; Zheng, Yuxin; Hansen, Paul; Hesselink, Lambertus

    2015-08-26

    The technique of using focused laser beams to trap and exert forces on small particles has enabled many pivotal discoveries in the nanoscale biological and physical sciences over the past few decades. The progress made in this field invites further study of even smaller systems and at a larger scale, with tools that could be distributed more easily and made more widely available. Unfortunately, the fundamental laws of diffraction limit the minimum size of the focal spot of a laser beam, which makes particles smaller than a half-wavelength in diameter hard to trap and generally prevents an operator from discriminating between particles which are closer together than one half-wavelength. This precludes the optical manipulation of many closely-spaced nanoparticles and limits the resolution of optical-mechanical systems. Furthermore, manipulation using focused beams requires beam-forming or steering optics, which can be very bulky and expensive. To address these limitations in the system scalability of conventional optical trapping our lab has devised an alternative technique which utilizes near-field optics to move particles across a chip. Instead of focusing laser beams in the far-field, the optical near field of plasmonic resonators produces the necessary local optical intensity enhancement to overcome the restrictions of diffraction and manipulate particles at higher resolution. Closely-spaced resonators produce strong optical traps which can be addressed to mediate the hand-off of particles from one to the next in a conveyor-belt-like fashion. Here, we describe how to design and produce a conveyor belt using a gold surface patterned with plasmonic C-shaped resonators and how to operate it with polarized laser light to achieve super-resolution nanoparticle manipulation and transport. The nano-optical conveyor belt chip can be produced using lithography techniques and easily packaged and distributed.

  13. Tectonic setting of synorogenic gold deposits of the Pacific Rim

    Science.gov (United States)

    Goldfarb, R.J.; Phillips, G.N.; Nokleberg, W.J.

    1998-01-01

    More than 420 million oz of gold were concentrated in circum-Pacific synorogenic quartz loades mainly during two periods of continental growth, one along the Gondwanan margin in the Palaeozoic and the other in the northern Pacific basin between 170 and 50 Ma. These ores have many features in common and can be grouped into a single type of lode gold deposit widespread throughout clastic sedimentary-rock dominant terranes. The auriferous veins contain only a few percent sulphide minerals, have gold:silver ratios typically greater than 1:1, show a distinct association with medium grade metamorphic rocks, and may be associated with large-scale fault zone. Ore fluids are consistently of low salinity and are CO2-rich. In the early and middle Palaeozoic in the southern Pacific basin, a single immense turbidite sequence was added to the eastern margin of Gondwanaland. Deformation of these rocks in southeastern Australia was accompanied by deposition of at least 80 million oz of gold in the Victorian sector of the Lachlan fold belt mainly during the Middle and Late Devonian. Lesser Devonian gold accumulations characterized the more northerly parts of the Gondwanan margin within the Hodgkinson-Broken River and Thomson fold belts. Additional lodes were emplaced in this flyschoid sequence in Devonian or earlier Palaeozoic times in what is now the Buller Terrane, Westland, New Zealand. Minor post-Devonian growth of Gondwanaland included terrane collision and formation of gold-bearing veins in the Permian in Australia's New England fold belt and in the Jurassic-Early Cretaceous in New Zealand's Otago schists. Collision and accretion of dozens of terranes for a 100-m.y.-long period against the western margin of North America and eastern margin of Eurasia led to widespread, lattest Jurassic to Eocene gold veining in the northern Pacific basin. In the former location, Late Jurassic and Early Cretaceous veins and related placer deposits along the western margin of the Sierra Nevada

  14. Gold-Mining

    DEFF Research Database (Denmark)

    Raaballe, J.; Grundy, B.D.

    2002-01-01

      Based on standard option pricing arguments and assumptions (including no convenience yield and sustainable property rights), we will not observe operating gold mines. We find that asymmetric information on the reserves in the gold mine is a necessary and sufficient condition for the existence...... of operating gold mines. Asymmetric information on the reserves in the mine implies that, at a high enough price of gold, the manager of high type finds the extraction value of the company to be higher than the current market value of the non-operating gold mine. Due to this under valuation the maxim of market...

  15. Using haptic feedback to increase seat belt use : traffic tech.

    Science.gov (United States)

    2011-07-01

    The legacy of research on increasing seat belt use has : focused on enactment of seat belt legislation, public education, : high-visibility police enforcement, and seat belt : reminder systems. Several behavioral programs have : produced large, susta...

  16. Origin of the asteroid belt

    International Nuclear Information System (INIS)

    Wetherill, G.W.

    1989-01-01

    Earlier work and concepts relevant to the origin of the asteroid belt are reviewed and considered in the context of the more general question of solar system origin. Several aspects of asteroidal origin by accumulation of smaller bodies have been addressed by new dynamic studies. Numerical and analytical solutions of the dynamical theory of planetesimal accumulation are characterized by a bifurcation into runaway and nonrunaway solutions. The differences in time scales resulting from runaway and nonrunaway growth can be more important than conventional time scale differences determined by heliocentric distances. This introduces new possibilities, e.g., planetary accumulation may be more rapid at the distance of Jupiter than in the asteroid belt, thus permitting Jupiter to control asteroidal growth. Although alternatives must be seriously considered, the most promising approach to asteroidal origin is one in which the initial surface density of the solar nebula varied smoothly between the terrestrial and giant-planet region. In the absence of external perturbations, it is found that runaway growth of excessively large asteroids would then occur on <1 Myr, but fairly modest external perturbations by Jupiter, Saturn or other perturbers, resulting in eccentricities ∼0.01 may quench runaways, truncate asteroidal growth at their present size, and then initiate the necessary loss of asteroidal material by mutual fragmentation

  17. The JET belt limiter tiles

    International Nuclear Information System (INIS)

    Deksnis, E.

    1988-09-01

    The belt limiter system, comprising two full toroidal rings of limiter tiles, was installed in JET in 1987. In consists of water-cooled fins with the limiter material in form of tile inbetween. The tiles are designed to absorb heat fluxes during irradiation without the surface temperature exceeding 2000 0 C and to radiate this heat between pulses to the water cooled sink whose temperature is lower than that of the vacuum vessel. An important feature of the design is to maximise the area of the radiating surface facing the water cooled fin. This leads to a tile depth much greater than the width of the tile facing the heat flux. Limiter tiles intercept particles flowing out of the plasma through the area between the two belt limiter rings and through remaining surface area of the plasma column. Power deposition to a limiter tile depends strongly on the shape of the plasma, the edge plasma properties as well as on the surface profile of the tiles. This paper will discuss the methodology that was followed in producing an optimized surface profile of the tiles. This shaped profile has the feature that the resulting power deposition profile is roughly similar for a wide range of plasma parameters. (author)

  18. Seat belt injuries and sigmoid colon trauma.

    OpenAIRE

    Eltahir, E M; Hamilton, D

    1997-01-01

    Colonic seat belt injuries are rare but carry higher mortality rates than small bowel injuries. The case of a 44 year old man is described who had severe sigmoid colon compression injury from his seat belt a few days after a road traffic accident.

  19. Intelligent Belt Conveyor Monitoring and Control

    NARCIS (Netherlands)

    Pang, Y.

    2010-01-01

    Belt conveyors have been used worldwide in continuous material transport for about 250 years. Traditional inspection and monitoring of large-scale belt conveyors focus on individual critical components and response to catastrophic system failures. To prevent operational problems caused by the lack

  20. 36 CFR 1004.15 - Safety belts.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Safety belts. 1004.15 Section 1004.15 Parks, Forests, and Public Property PRESIDIO TRUST VEHICLES AND TRAFFIC SAFETY § 1004.15 Safety... administered by the Presidio Trust will have the safety belt or child restraint system properly fastened at all...

  1. Feed chute geometry for minimum belt wear

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, A W; Wiche, S J [University of Newcastle, Newcastle, NSW (Australia). Centre for Bulk Solids and Particulate Technologies

    1998-09-01

    The paper is concerned with the feeding and transfer of bulk solids in conveyor belt operation. The paper focuses on chute design where the objective is to prevent spillage and minimise both chute and belt wear. It is shown that these objectives may be met through correct dynamic design of the chute and by directing the flow of bulk solids onto the belt at an acceptable incidence angle. The aim is to match the tangential velocity component of the feed velocity as close as possible to the belt velocity. At the same time, it is necessary to limit the impact pressure due to the change in momentum of the bulk solid as it feeds onto the belt. 2 refs., 8 figs.

  2. Phanerozoic continental growth and gold metallogeny of Asia

    Science.gov (United States)

    Goldfarb, Richard J.; Taylor, Ryan D.; Collins, Gregory S.; Goryachev, Nicolay A.; Orlandini, Omero Felipe

    2014-01-01

    The Asian continent formed during the past 800 m.y. during late Neoproterozoic through Jurassic closure of the Tethyan ocean basins, followed by late Mesozoic circum-Pacific and Cenozoic Himalayan orogenies. The oldest gold deposits in Asia reflect accretionary events along the margins of the Siberia, Kazakhstan, North China, Tarim–Karakum, South China, and Indochina Precambrian blocks while they were isolated within the Paleotethys and surrounding Panthalassa Oceans. Orogenic gold deposits are associated with large-scale, terrane-bounding fault systems and broad areas of deformation that existed along many of the active margins of the Precambrian blocks. Deposits typically formed during regional transpressional to transtensional events immediately after to as much as 100 m.y. subsequent to the onset of accretion or collision. Major orogenic gold provinces associated with this growth of the Asian continental mass include: (1) the ca. 750 Ma Yenisei Ridge, ca. 500 Ma East Sayan, and ca. 450–350 Ma Patom provinces along the southern margins of the Siberia craton; (2) the 450 Ma Charsk belt of north-central Kazakhstan; (3) the 310–280 Ma Kalba belt of NE Kazakhstan, extending into adjacent NW Xinjiang, along the Siberia–Kazakhstan suture; (4) the ca. 300–280 Ma deposits within the Central Asian southern and middle Tien Shan (e.g., Kumtor, Zarmitan, Muruntau), marking the closure of the Turkestan Ocean between Kazakhstan and the Tarim–Karakum block; (5) the ca. 190–125 Ma Transbaikal deposits along the site of Permian to Late Jurassic diachronous closure of the Mongol–Okhotsk Ocean between Siberia and Mongolia/North China; (6) the probable Late Silurian–Early Devonian Jiagnan belt formed along the margin of Gondwana at the site of collision between the Yangtze and Cathaysia blocks; (7) Triassic deposits of the Paleozoic Qilian Shan and West Qinling orogens along the SW margin of the North China block developed during collision of South China

  3. Gold and uranium extraction

    International Nuclear Information System (INIS)

    James, G.S.; Davidson, R.J.

    1977-01-01

    A process for extracting gold and uranium from an ore containing them both comprising the steps of pulping the finely comminuted ore with a suitable cyanide solution at an alkaline pH, acidifying the pulp for uranium dissolution, adding carbon activated for gold recovery to the pulp at a suitable stage, separating the loaded activated carbon from the pulp, and recovering gold from the activated carbon and uranium from solution

  4. Gold mineralogy and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Cashion, J.D.; Brown, L.J. [Monash University, Physics Department (Australia)

    1998-12-15

    Several examples are examined in which Moessbauer spectroscopic analysis of gold mineral samples, treated concentrates and extracted species has provided information not obtainable by competing techniques. Descriptions are given of current work on bacterial oxidation of pyritic ores and on the adsorbed species from gold extracted from cyanide and chloride solutions onto activated carbon and polyurethane foams. The potential benefits for the gold mining industry from Moessbauer studies and some limitations on the use of the technique are also discussed.

  5. Gold mineralogy and extraction

    International Nuclear Information System (INIS)

    Cashion, J.D.; Brown, L.J.

    1998-01-01

    Several examples are examined in which Moessbauer spectroscopic analysis of gold mineral samples, treated concentrates and extracted species has provided information not obtainable by competing techniques. Descriptions are given of current work on bacterial oxidation of pyritic ores and on the adsorbed species from gold extracted from cyanide and chloride solutions onto activated carbon and polyurethane foams. The potential benefits for the gold mining industry from Moessbauer studies and some limitations on the use of the technique are also discussed

  6. Observed use of automatic seat belts in 1987 cars.

    Science.gov (United States)

    Williams, A F; Wells, J K; Lund, A K; Teed, N

    1989-10-01

    Usage of the automatic belt systems supplied by six large-volume automobile manufacturers to meet the federal requirements for automatic restraints were observed in suburban Washington, D.C., Chicago, Los Angeles, and Philadelphia. The different belt systems studied were: Ford and Toyota (motorized, nondetachable automatic shoulder belt), Nissan (motorized, detachable shoulder belt), VW and Chrysler (nonmotorized, detachable shoulder belt), and GM (nonmotorized detachable lap and shoulder belt). Use of automatic belts was significantly greater than manual belt use in otherwise comparable late-model cars for all manufacturers except Chrysler; in Chrysler cars, automatic belt use was significantly lower than manual belt use. The automatic shoulder belts provided by Ford, Nissan, Toyota, and VW increased use rates to about 90%. Because use rates were lower in Ford cars with manual belts, their increase was greater. GM cars had the smallest increase in use rates; however, lap belt use was highest in GM cars. The other manufacturers supply knee bolsters to supplement shoulder belt protection; all--except VW--also provide manual lap belts, which were used by about half of those who used the automatic shoulder belt. The results indicate that some manufacturers have been more successful than others in providing automatic belt systems that result in high use that, in turn, will mean fewer deaths and injuries in those cars.

  7. Drive Alive: Teen Seat Belt Survey Program

    Directory of Open Access Journals (Sweden)

    Loftin, Laurel

    2010-08-01

    Full Text Available Objective: To increase teen seat belt use among drivers at a rural high school by implementing the Drive Alive Pilot Program (DAPP, a theory-driven intervention built on highway safety best practices.Methods: The first component of the program was 20 observational teen seat belt surveys conducted by volunteer students in a high school parking lot over a 38-month period before and after the month-long intervention. The survey results were published in the newspaper. The second component was the use of incentives, such as gift cards, to promote teen seat belt use. The third component involved disincentives, such as increased police patrol and school policies. The fourth component was a programmatic intervention that focused on education and media coverage of the DAPP program.Results: Eleven pre-intervention surveys and nine post-intervention surveys were conducted before and after the intervention. The pre- and post-intervention seat belt usage showed significant differences (p<0.0001. The average pre-intervention seat belt usage rate was 51.2%, while the average post-intervention rate was 74.5%. This represents a percentage point increase of 23.3 in seat belt use after the DAPP intervention.Conclusion: Based on seat belt observational surveys, the DAPP was effective in increasing seat belt use among rural high school teenagers. Utilizing a theory-based program that builds on existing best practices can increase the observed seat belt usage among rural high school students. [West J Emerg Med. 2010; 11(3: 280-283.

  8. Belt design central to conveyor performance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-15

    While a conveyor system comprises a complex range of components, it is the belt design which ultimately dictates its core performance and reliability. The complexity of modern systems can be seen by the recent contract awarded to ThyssenKrupp Foerdertechnik (TKF) to supply systems for a new steel plant (including a coking plant and a power plant) to be built in Sepetiba Bay in Brazil. Phoenix has designed the Phoenotec system to protect steel cord conveyor belts. Fenner Dunlop has developed Fenaplast belting with nylon or polyester load-bearing warp and weft yarns for good impact resistance. 2 photos.

  9. 30 CFR 57.4503 - Conveyor belt slippage.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Conveyor belt slippage. 57.4503 Section 57.4503... Control Installation/construction/maintenance § 57.4503 Conveyor belt slippage. (a) Surface belt conveyors...) Underground belt conveyors shall be equipped with a detection system capable of automatically stopping the...

  10. 30 CFR 56.4503 - Conveyor belt slippage.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Conveyor belt slippage. 56.4503 Section 56.4503... Control Installation/construction/maintenance § 56.4503 Conveyor belt slippage. Belt conveyors within... shall attend the belt at the drive pulley when it is necessary to operate the conveyor while temporarily...

  11. 30 CFR 75.1403-5 - Criteria-Belt conveyors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Criteria-Belt conveyors. 75.1403-5 Section 75... Criteria—Belt conveyors. (a) Positive-acting stop controls should be installed along all belt conveyors... can be stopped or started at any location. (b) Belt conveyors used for regularly scheduled mantrips...

  12. Compliance with Seat Belt Use in Makurdi, Nigeria: An ...

    African Journals Online (AJOL)

    Background: Seat belts are designed to reduce injuries due to road crash among vehicle occupants. Aims: This study aims to determine the availability of seat belt in vehicles and compliance with seat belt use among vehicle occupants. Materials and methods: This was a 24‑h direct observational study of seat belt usage ...

  13. Simulation of engine auxiliary drive V-belt slip motion. Part 1. Development of belt slip model; Engine hoki V belt slip kyodo no simulation. 1. Belt slip model no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kurisu, T [Mazda Motor Corp., Hiroshima (Japan)

    1997-10-01

    V-belts are widely used for driving auxiliary components of an engine. Inadequet design of such belt system sometimes results in troubles such as belt squeak, side rubber separation and/or bottom rubber crack. However, there has been no design tools which can predict belt slip quantitatively. The author developed a motion simulation program of Auxiliary Drive V-Belt System considering belt slip. The program showed good prediction accuracy for belt slip motion. This paper describes the simulation model. 1 ref., 12 figs.

  14. BROOKHAVEN: High energy gold

    International Nuclear Information System (INIS)

    Bleser, Ed

    1992-01-01

    On April 24, Brookhaven's Alternating Gradient Synchrotron (AGS) started to deliver gold ions at 11.4 GeV per nucleon (2,000 GeV per ion) to experimenters who were delighted not only to receive the world's highest energy gold beam but also to receive it on schedule

  15. Handbook Timing Belts Principles, Calculations, Applications

    CERN Document Server

    Perneder, Raimund

    2012-01-01

    Timing belts offer a broad range of innovative drivetrain solutions; they allow low-backlash operation in robot systems, they are widely used in automated processes and industrial handling involving highly dynamic start-up loads, they are low-maintenance solutions for continuous operation applications, and they can guarantee exact positioning at high operating speeds. Based on his years of professional experience, the author has developed concise guidelines for the dimensioning of timing belt drives and presents proven examples from the fields of power transmission, transport and linear transfer technology. He offers definitive support for dealing with and compensating for adverse operating conditions and belt damage, as well as advice on drive optimization and guidelines for the design of drivetrain details and supporting systems. All market-standard timing belts are listed as brand neutral. Readers will discover an extensive bibliography with information on the various manufacturers and their websites. This...

  16. Dynamics Analysis and Modeling of Rubber Belt in Large Mine Belt Conveyors

    OpenAIRE

    Gao Yang

    2014-01-01

    Rubber belt not only is one of the key components of belt conveyor, but also affects the overall performance of the core part. Research on dynamics analysis of large conveyor not only helps to improve the reliability and design level, but also can guide the rational selection of conveyor safety factor, and effectively reduce the cost of the conveyor belt. Based on unique viscoelastic properties of belt conveyor, it was simplified as one-dimensional viscoelastic rod in this study, and then a d...

  17. The Stability of the Conveyor Belt Pontoon

    Directory of Open Access Journals (Sweden)

    Jiří PODEŠVA

    2011-06-01

    Full Text Available To lead the conveyor belt transport cross water area the pontoon are used to support the carrying structure of the belts. The accident can happen when the pontoon turnover. For this reason the pontoon stability is investigated. The stability is described by the Reed’s diagram. This can be constructed analytically or via numerical modeling. Both methods are described in the paper.

  18. Belt Conveyor Dynamic Characteristics and Influential Factors

    OpenAIRE

    Li, Junxia; Pang, Xiaoxu

    2018-01-01

    This paper uses the Kelvin-Voigt viscoelastic model to establish the continuous dynamic equations for tail hammer tension belt conveyors. The viscoelastic continuity equations are solved using the generalized coordinate method. We analyze various factors influencing longitudinal vibration of the belt conveyor by simulation and propose a control strategy to limit the vibration. The proposed approach and control strategy were verified by several experimental researches and cases. The proposed a...

  19. Seat-belt message and the law?

    Science.gov (United States)

    Sengupta, S K; Patil, N G; Law, G

    1989-09-01

    This paper attempts to draw together available information on the use of seat belts, one of the most important safety devices for a person in a car. Considering the high rate of mortality and morbidity due to road traffic accidents in Papua New Guinea the authors strongly feel that seat-belt usage should be made compulsory. When one looks at the history of the implementation of such a successful countermeasure in other countries it seems that legislation is the only answer.

  20. Jupiter's magnetosphere and radiation belts

    Science.gov (United States)

    Kennel, C. F.; Coroniti, F. V.

    1979-01-01

    Radioastronomy and Pioneer data reveal the Jovian magnetosphere as a rotating magnetized source of relativistic particles and radio emission, comparable to astrophysical cosmic ray and radio sources, such as pulsars. According to Pioneer data, the magnetic field in the outer magnetosphere is radially extended into a highly time variable disk-shaped configuration which differs fundamentally from the earth's magnetosphere. The outer disk region, and the energetic particles confined in it, are modulated by Jupiter's 10 hr rotation period. The entire outer magnetosphere appears to change drastically on time scales of a few days to a week. In addition to its known modulation of the Jovian decametric radio bursts, Io was found to absorb some radiation belt particles and to accelerate others, and most importantly, to be a source of neutral atoms, and by inference, a heavy ion plasma which may significantly affect the hydrodynamic flow in the magnetosphere. Another important Pioneer finding is that the Jovian outer magnetosphere generates, or permits to escape, fluxes of relativistic electrons of such intensities that Jupiter may be regarded as the dominant source of 1 to 30 MeV cosmic ray electrons in the heliosphere.

  1. Bismuth-silver mineralization in the Sergozerskoe gold occurrence

    Directory of Open Access Journals (Sweden)

    Kalinin A. A.

    2017-03-01

    Full Text Available Bismuth-silver mineralization attendant to gold mineralization in the Sergozerskoe gold occurrence has been studied in detail. Bi-Ag mineralization is connected with diorite porphyry dykes, which cut volcanic-sedimentary Lopian complexes of the Strel'ninsky greenstone belt – hornblendite and actinolite-chlorite amphibolites, biotite and bi-micaceous gneisses. Distribution of Bi-Ag mineralization similar to gold mineralization is controlled by 80 m thick zone of silicification. Bi minerals are found in brecciated diorite porphyry. Bismuth-silver mineralization includes native metals (bismuth, electrum, silver, tellurides (hedleyite, hessite, selenides (ikunolite, sulfides and sulfosalts of Bi and Ag (matildite, lillianite, eckerite, jalpaite, prustite, acanthite, a few undiagnosed minerals. All Bi and Ag minerals associate with galena. Composition of mineralization evolved from early to late stages of development, depending on intensity of rock alteration. The earliest Bi-Ag minerals were native bismuth and hedleyite formed dissemination in galena, and electrum with 30-45 mass.% Au. Later native bismuth was partly substituted by silver and bismuth sulfosalts and bismuth sulfides. The latest minerals were low-temperature silver sulfides eckerite, jalpaite, and acanthite, which were noted only in the most intensively altered rocks. As soon as the process of formation of Bi-Ag mineralization is the same as formation of gold, findings of bismuth-silver mineralization can serve as a positive exploration sign for gold in the region.

  2. Microfluidic magnetic bead conveyor belt.

    Science.gov (United States)

    van Pelt, Stijn; Frijns, Arjan; den Toonder, Jaap

    2017-11-07

    Magnetic beads play an important role in the miniaturization of clinical diagnostics systems. In lab-on-chip platforms, beads can be made to link to a target species and can then be used for the manipulation and detection of this species. Current bead actuation systems utilize complex on-chip coil systems that offer low field strengths and little versatility. We demonstrate a novel system based on an external rotating magnetic field and on-chip soft-magnetic structures to focus the field locally. These structures were designed and optimized using finite element simulations in order to create a number of local flux density maxima. These maxima, to which the magnetic beads are attracted, move over the chip surface in a continuous way together with the rotation of the external field, resulting in a mechanism similar to that of a conveyor belt. A prototype was fabricated using PDMS molding techniques mixed with iron powder for the magnetic structures. In the subsequent experiments, a quadrupole electromagnet was used to create the rotating external field. We observed that beads formed agglomerates that rolled over the chip surface, just above the magnetic structures. Field rotation frequencies between 0.1-50 Hz were tested resulting in magnetic bead speeds of over 1 mm s -1 for the highest frequency. With this, we have shown that our novel concept works, combining a simple design and simple operation with a powerful and versatile method for bead actuation. This makes it a promising method for further research and utilization in lab-on-chip systems.

  3. Analysis of stress distribution of timing belts by FEM; Yugen yosoho ni yoru timing belt oryoku kaiseki (belt code oryoku bunpu kaiseki hokoku)

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Y; Tomono, K; Takahashi, H; Uchida, T [Honda R and D Co. Ltd., Tokyo (Japan)

    1997-10-01

    A model of the belt analyzed by-ABAQUS (: a general nonlinear finite element program) successfully confirmed the mechanism that generates the belt cord stress. A quite good agreement between experimental and computed results for the stress distribution of the belt cord. It is found that maximum stress of the cords occurs near the root of the tooth by calculation, where the belt cords break off. 3 refs., 9 figs.

  4. Medicinal gold compounds

    International Nuclear Information System (INIS)

    Parish, R.V.; Cottrill, S.M.

    1987-01-01

    A major use of gold compounds in the pharmaceutical industry is for anti-arthritic agents. The disease itself is not understood and little is known about the way in which the drugs act, but detailed pictures of the distribution of gold in the body are available, and some of the relevant biochemistry is beginning to emerge. The purpose of this article is to give a survey of the types of compounds presently employed in medicine, of the distribution of gold in the body which results from their use, and of some relevant chemistry. Emphasis is placed on results obtained in the last few years

  5. Radiometric measurement independent of profile. Belt weighers

    International Nuclear Information System (INIS)

    Otto, J.

    1986-01-01

    Radiometric measuring techniques allow contactless determination of the material carried by belt conveyors. Data defining the material is obtained via attenuation of gamma rays passing through the material on the belt. The method applies the absorption law according to Lambert-Beer, which has to be corrected by a build-up factor because of the stray radiation induced by the Compton effect. The profile-dependent error observed with conventional radiometric belt weighers is caused by the non-linearity of the absorption law in connection with the simultaneous summation of the various partial rays in a detector. The scanning method allows separate evaluation of the partial rays' attenuation and thus yields the correct data of the material carried, regardless of the profile. The scanning method is applied on a finite number of scanning sections, and a residual error has to be taken into account. The stochastics of quantum emission and absorption leads to an error whose expectation value is to be taken into account in the scanning algorithm. As the conveyor belt is in motion during the process of measurements, only part of the material conveyed is irradiated. The resulting assessment error is investigated as a function of the autocorrelation function of the material on the belt. (orig./HP) [de

  6. IDENTIFYING COLLISIONAL FAMILIES IN THE KUIPER BELT

    International Nuclear Information System (INIS)

    Marcus, Robert A.; Ragozzine, Darin; Murray-Clay, Ruth A.; Holman, Matthew J.

    2011-01-01

    The identification and characterization of numerous collisional families-clusters of bodies with a common collisional origin-in the asteroid belt has added greatly to the understanding of asteroid belt formation and evolution. More recent study has also led to an appreciation of physical processes that had previously been neglected (e.g., the Yarkovsky effect). Collisions have certainly played an important role in the evolution of the Kuiper Belt as well, though only one collisional family has been identified in that region to date, around the dwarf planet Haumea. In this paper, we combine insights into collisional families from numerical simulations with the current observational constraints on the dynamical structure of the Kuiper Belt to investigate the ideal sizes and locations for identifying collisional families. We find that larger progenitors (r ∼ 500 km) result in more easily identifiable families, given the difficulty in identifying fragments of smaller progenitors in magnitude-limited surveys, despite their larger spread and less frequent occurrence. However, even these families do not stand out well from the background. Identifying families as statistical overdensities is much easier than characterizing families by distinguishing individual members from interlopers. Such identification seems promising, provided the background population is well known. In either case, families will also be much easier to study where the background population is small, i.e., at high inclinations. Overall, our results indicate that entirely different techniques for identifying families will be needed for the Kuiper Belt, and we provide some suggestions.

  7. The Gold Standard Programme

    DEFF Research Database (Denmark)

    Neumann, Tim; Rasmussen, Mette; Ghith, Nermin

    2013-01-01

    To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates.......To evaluate the real-life effect of an evidence-based Gold Standard Programme (GSP) for smoking cessation interventions in disadvantaged patients and to identify modifiable factors that consistently produce the highest abstinence rates....

  8. Gold nanoprobes for theranostics

    Science.gov (United States)

    Panchapakesan, Balaji; Book-Newell, Brittany; Sethu, Palaniappan; Rao, Madhusudhana; Irudayaraj, Joseph

    2011-01-01

    Gold nanoprobes have become attractive diagnostic and therapeutic agents in medicine and life sciences research owing to their reproducible synthesis with atomic level precision, unique physical and chemical properties, versatility of their morphologies, flexibility in functionalization, ease of targeting, efficiency in drug delivery and opportunities for multimodal therapy. This review highlights some of the recent advances and the potential for gold nanoprobes in theranostics. PMID:22122586

  9. Facts and Fantasies about Gold

    OpenAIRE

    Klement, Joachim

    2015-01-01

    Due to the increasing popularity of gold as an investment the demand for effective risk management techniques for gold investments has increased as well. In this paper we analyze several drivers of the price of gold that have been proposed in the past. Our analysis indicates that short-term volatility of the price of gold remains rather unpredictable with many of the explanations like the fund flows in physical gold ETF either unreliable or unstable over time. Our analysis suggests that there...

  10. Storm-time radiation belt electron dynamics: Repeatability in the outer radiation belt

    Science.gov (United States)

    Murphy, K. R.; Mann, I. R.; Rae, J.; Watt, C.; Boyd, A. J.; Turner, D. L.; Claudepierre, S. G.; Baker, D. N.; Spence, H. E.; Reeves, G. D.; Blake, J. B.; Fennell, J. F.

    2017-12-01

    During intervals of enhanced solar wind driving the outer radiation belt becomes extremely dynamic leading to geomagnetic storms. During these storms the flux of energetic electrons can vary by over 4 orders of magnitude. Despite recent advances in understanding the nature of competing storm-time electron loss and acceleration processes the dynamic behavior of the outer radiation belt remains poorly understood; the outer radiation belt can exhibit either no change, an enhancement, or depletion in radiation belt electrons. Using a new analysis of the total radiation belt electron content, calculated from the Van Allen probes phase space density (PSD), we statistically analyze the time-dependent and global response of the outer radiation belt during storms. We demonstrate that by removing adiabatic effects there is a clear and repeatable sequence of events in storm-time radiation belt electron dynamics. Namely, the relativistic (μ=1000 MeV/G) and ultra-relativistic (μ=4000 MeV/G) electron populations can be separated into two phases; an initial phase dominated by loss followed by a second phase dominated by acceleration. At lower energies, the radiation belt seed population of electrons (μ=150 MeV/G) shows no evidence of loss but rather a net enhancement during storms. Further, we investigate the dependence of electron dynamics as a function of the second adiabatic invariant, K. These results demonstrate a global coherency in the dynamics of the source, relativistic and ultra-relativistic electron populations as function of the second adiabatic invariant K. This analysis demonstrates two key aspects of storm-time radiation belt electron dynamics. First, the radiation belt responds repeatably to solar wind driving during geomagnetic storms. Second, the response of the radiation belt is energy dependent, relativistic electrons behaving differently than lower energy seed electrons. These results have important implications in radiation belt research. In particular

  11. Security Belt for Wireless Implantable Medical Devices.

    Science.gov (United States)

    Kulaç, Selman

    2017-09-19

    In this study, a new protective design compatible with existing non-secure systems was proposed, since it is focused on the secure communication of wireless IMD systems in all transmissions. This new protector is an external wearable device and appears to be a belt fitted around for the patients IMD implanted. However, in order to provide effective full duplex transmissions and physical layer security, some sophisticated transceiver antennas have been placed on the belt. In this approach, beam-focused multi-antennas in optimal positions on the belt are randomly switched when transmissions to the IMD are performed and multi-jammer switching with MRC combining or majority-rule based receiving techniques are applied when transmissions from the IMD are carried out. This approach can also reduce the power consumption of the IMDs and contribute to the prolongation of the IMD's battery life.

  12. Estimates Of Radiation Belt Remediation Requirements

    Science.gov (United States)

    Tuszewski, M.; Hoyt, R. P.; Minor, B. M.

    2004-12-01

    A low-Earth orbit nuclear detonation could produce an intense artificial radiation belt of relativistic electrons. Many satellites would be destroyed within a few weeks. We present here simple estimates of radiation belt remediation by several different techniques, including electron absorption by gas release, pitch angle scattering by steady electric and magnetic fields from tether arrays, and pitch angle scattering by wave-particle interactions from in-situ transmitters. For each technique, the mass, size, and power requirements are estimated for a one-week remediation (e-folding) timescale, assuming that a 10 kTon blast trapped 1024 fission product electrons (1 to 8 MeV) at L = 1.5 in a dipolar belt of width dL = 0.1.

  13. Biosynthesis of gold nanoparticles using diatoms-silica-gold and EPS-gold bionanocomposite formation

    OpenAIRE

    Schröfel, Adam; Kratošová, Gabriela; Bohunická, Markéta; Dobročka, Edmund; Vávra, Ivo

    2011-01-01

    Novel synthesis of gold nanoparticles, EPS-gold, and silica-gold bionanocomposites by biologically driven processes employing two diatom strains (Navicula atomus, Diadesmis gallica) is described. Transmission electron microscopy (TEM) and electron diffraction analysis (SAED) revealed a presence of gold nanoparticles in the experimental solutions of the diatom culture mixed with tetrachloroaureate. Nature of the gold nanoparticles was confirmed by X-ray diffraction studies. Scanning electron m...

  14. SMALL MAIN-BELT ASTEROID SPECTROSCOPIC SURVEY, PHASE II

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains visible-wavelength (0.435-0.925 micron) spectra for 1341 main-belt asteroids observed during the second phase of the Small Main-belt Asteroid...

  15. Structural appraisal of the Gadag schist belt from gravity investigations

    Indian Academy of Sciences (India)

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

    From qualitative analysis of the gravity data, several tectonic features are ... major types of schist belts are identified in the ... Dharwar craton; Gadag schist belt; gravity method; inversion. ..... the Research Associateship of Dr D Himabindu.

  16. Low-Impact Exploration for Gold in the Scottish Caledonides.

    Science.gov (United States)

    Rice, Samuel; Cuthbert, Simon; Hursthouse, Andrew; Broetto, Gabriele

    2017-04-01

    The Caledonian orogenic belt of the northern British Isles hosts some significant gold deposits. However, gold mineralization in the region is underexplored. Some of the most prospective areas identified by rich alluvial gold anomalies are environmentally and culturally sensitive. Traditional mineral exploration methods can have a range of negative environmental, social and economic impacts. The regional tourism economy is dependent on outdoor activities, landscape quality, wildlife and industrial heritage and has the potential to be disrupted by mineral resource developments. Low-cost, low-impact exploration strategies are therefore, key to sustainably developing the mineral resource potential. Research currently in progress in part of the Scottish Caledonides aims to develop protocols for more sustainable exploration. We are using a range of geoscience techniques to characterize the mineral system, improve exploration targeting and reduce negative impacts. To do this we targeted an area with a large preexisting dataset (e.g. stream sediment geochemistry, geomorphology, structural geology, petrology, geophysics, mine data) that can be synthesized and analyzed in a GIS. Part of the work aims to develop and test a model for gold dispersion in the surface environment that accounts for climatic and anthropogenic influences in order to locate bedrock sources. This multidisciplinary approach aims to reduce the target areas for subsequent exploration activities such as soil sampling, excavation and drilling.

  17. 30 CFR 75.1108 - Approved conveyor belts.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved conveyor belts. 75.1108 Section 75... Fire-Resistant Hydraulic Fluids on Underground Equipment § 75.1108 Approved conveyor belts. (a) Until December 31, 2009 conveyor belts placed in service in underground coal mines shall be: (1) Approved under...

  18. Green operations of belt conveyors by means of speed control

    NARCIS (Netherlands)

    He, D.; Pang, Y.; Lodewijks, G.

    2017-01-01

    Belt conveyors can be partially loaded due to the variation of bulk material flow loaded onto the conveyor. Speed control attempts to reduce the belt conveyor energy consumption and to enable the green operations of belt conveyors. Current research of speed control rarely takes the conveyor dynamics

  19. Gravity inferred subsurface structure of Gadwal Schist belt, Andhra

    Indian Academy of Sciences (India)

    Detailed gravity data collected across the Gadwal schist belt in the state of Andhra Pradesh show an 8.4 mgal residual gravity anomaly associated with meta-sediments/volcanics of the linear NNW-SSE trending schist belt that shows metamorphism from green schist to amphibolite facies. This schist belt is flanked on either ...

  20. 14 CFR 125.211 - Seat and safety belts.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Seat and safety belts. 125.211 Section 125... Requirements § 125.211 Seat and safety belts. (a) No person may operate an airplane unless there are available... the airplane who is at least 2 years old; and (2) An approved safety belt for separate use by each...

  1. Klippen Belt, Flysch Belt and Inner Western Carpathian Paleogene Basin Relations in the Northern Slovakia by Magnetotelluric Imaging

    Czech Academy of Sciences Publication Activity Database

    Majcin, D.; Bezák, V.; Klanica, Radek; Vozár, J.; Pek, Josef; Bilčík, D.; Telecký, Josef

    (2018) ISSN 0033-4553 Institutional support: RVO:67985530 Keywords : magnetotellurics * Western Carpathians * Klippen Belt * Flysch Belt * Inner Carpathian Paleogene Subject RIV: DE - Earth Magnetism, Geodesy, Geography OBOR OECD: Physical geography Impact factor: 1.591, year: 2016

  2. Bayesian inference of radiation belt loss timescales.

    Science.gov (United States)

    Camporeale, E.; Chandorkar, M.

    2017-12-01

    Electron fluxes in the Earth's radiation belts are routinely studied using the classical quasi-linear radial diffusion model. Although this simplified linear equation has proven to be an indispensable tool in understanding the dynamics of the radiation belt, it requires specification of quantities such as the diffusion coefficient and electron loss timescales that are never directly measured. Researchers have so far assumed a-priori parameterisations for radiation belt quantities and derived the best fit using satellite data. The state of the art in this domain lacks a coherent formulation of this problem in a probabilistic framework. We present some recent progress that we have made in performing Bayesian inference of radial diffusion parameters. We achieve this by making extensive use of the theory connecting Gaussian Processes and linear partial differential equations, and performing Markov Chain Monte Carlo sampling of radial diffusion parameters. These results are important for understanding the role and the propagation of uncertainties in radiation belt simulations and, eventually, for providing a probabilistic forecast of energetic electron fluxes in a Space Weather context.

  3. Composite Microdiscs with a Magnetic Belt

    DEFF Research Database (Denmark)

    Knaapila, Matti; Høyer, Henrik; Helgesen, Geir

    2015-01-01

    , the spontaneous aggregation of composite particles is suppressed when dispersed into liquid, which is attributed to the increased particle size, reduced magnetic susceptibility, and the shape of the magnetic domain distribution within the particles (spherical versus a belt). When the composite particles...

  4. Pregnancy: Should I Use a Seat Belt?

    Science.gov (United States)

    ... passenger has not been shown to affect the safety of an unborn baby in a crash. Injuries from car crashes tend to be less serious in people who are sitting in the back seat. If you are not driving, you may want to sit in the back seat. It is still important to wear a seat belt, no matter where ...

  5. The thrust belts of Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, F.C.

    1993-08-01

    Most of the Basin and Range physiographic province of western North America is now believed to be part of the overthrust. The more obvious overthrust belt along the eastern edge of the Basin and Range Province is named the Sevier orogenic belt, where older rocks are observed thrust onto younger rocks. More detailed surface geological mapping, plus deep multiple-fold geophysical work and many oil and gas wildcat wells, have confirmed an east-vergent shortened and stacked sequence is present in many places in the Basin and Range. This western compressive deformed area in east central Nevada is now named the Elko orogenic belt by the U.S. Geological Survey. This older compressed Elko orogenic belt started forming approximately 250 m.y. ago when the North American plate started to move west as the Pangaea supercontinent started to fragment. The North American plate moved west under the sediments of the Miogeocline that were also moving west. Surface-formed highlands and oceanic island arcs on the west edge of the North American plate restricted the westward movement of the sediments in the Miogeocline, causing east-vergent ramp thrusts to form above the westward-moving North American plate. The flat, eastward-up-cutting thrust assemblages moved on the detachment surfaces.

  6. Design aspects of multiple driven belt conveyors

    NARCIS (Netherlands)

    Nuttall, A.J.G.

    2007-01-01

    Worldwide belt conveyors are used to transport a great variety of bulk solid materials. The desire to carry higher tonnages over longer distances and more diverse routes, while keeping exploitation costs as low as possible, has fuelled many technological advances. An interesting development in the

  7. Energy efficient idler for belt conveyor systems

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, A.K.; Chattopadhyay, A. [Indian School of Mines Univ., Dhanbad (India). Dept. of Mechanical Engineering and Mining; Soni, R.; Bhattnagar, M.

    2009-07-01

    In today's economic and legal environment, energy efficiency has become more important than ever. This paper proposes a new design of idler rollers for belt conveyors that could help to them even more efficient by reducing their energy consumption and also their CO{sub 2} footprint. (orig.)

  8. Belts and Chains. FOS: Fundamentals of Service.

    Science.gov (United States)

    John Deere Co., Moline, IL.

    This manual on belts and chain drives is one of a series of power mechanics texts and visual aids on theory, of operation, diagnosis, and repair of automotive and off-the-road agricultural and construction equipment. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and…

  9. Electron Radiation Belts of the Solar System

    Science.gov (United States)

    Mauk, Barry; Fox, Nicola

    To address the question of what factors dictate similarities and differences between radiation belts, we present comparisons between the electron radiation belt spectra of all five strongly magnetized planets within the solar system: Earth, Jupiter, Saturn, Uranus, and Neptune. We choose the highest intensity observed electron spectrum within each system (highest specifically near 1 MeV) and compare them against expectations based on the so-called Kennel-Petschek limit (KP; 1966) for each system. For evaluating the KP limit, we begin with the new relativis-tically correct formulation of Summers et al. (2009) but then add several refinements of our own. Specifically, we: 1) utilized a much more flexible analytic spectral shape that allows us to accurately fit observed radiation belt spectra; 2) adopt the point of view that the anisotropy parameter is not a free parameter but must take on a minimal value, as originally proposed by Kennel and Petschek (1966); and 3) examine the differential characteristics of the KP limit along the lines of what Schulz and Davidson (1988) performed for the non-relativistic formula-tion. We find that three factors limit the highest electron radiation belt intensities within solar system planetary magnetospheres: a) whistler mode interactions that limit spectral intensities to a differential Kennel-Petschek limit (3 planets); b) the absence of robust acceleration pro-cesses associated with injection dynamics (1 planet); and c) material interactions between the radiation particles and clouds of gas and dust (1 planet).

  10. Green Belt Europe - borders separate, nature unites

    Science.gov (United States)

    Uwe Friedel

    2015-01-01

    During the period of the Cold War between 1945 and 1989, a "Green Belt" of valuable pristine landscapes developed along the border line between Eastern and Western Europe, the intensively fortified and guarded so called Iron Curtain. Due to the remoteness of the border areas, a high number of national parks and other large conservation areas can be found...

  11. Mafic magmatism in the Bakhuis Granulite Belt

    NARCIS (Netherlands)

    Klaver, M.; de Roever, E.W.F.; Thijssen, A.C.D.; Bleeker, W.; Söderlund, U.; Chamberlain, K.; Ernst, R.; Berndt, J.; Zeh, A.

    2015-01-01

    The Bakhuis Granulite Belt (BGB) is a metamorphic terrain within the Guiana Shield that experienced ultrahigh-temperature (UHT) metamorphism at 2.07–2.05Ga. In the southwest of the BGB, the Kabalebo charnockites were emplaced at ca. 1.99Ga and thus postdate UHT metamorphism by at least 60Myr. Two

  12. GOLD IS EARNED FROM THE PRODUCTION OF THAI GOLD LEAF

    Directory of Open Access Journals (Sweden)

    Dirk Bax

    2010-06-01

    Full Text Available Thai people like to cover sacred objects or things dear to them with gold leaf.. Statues of Buddha are sometimes covered with so many layers of gold leaf that they become formless figures, that can hardly be recognized. Portraits of beloved ancestors, statues of elephants and grave tombs are often covered with gold leaf. If one considers the number of Thai people and the popularity of the habit, the amount of gold involved could be considerable.

  13. Gold film with gold nitride - A conductor but harder than gold

    International Nuclear Information System (INIS)

    Siller, L.; Peltekis, N.; Krishnamurthy, S.; Chao, Y.; Bull, S.J.; Hunt, M.R.C.

    2005-01-01

    The formation of surface nitrides on gold films is a particularly attractive proposition, addressing the need to produce harder, but still conductive, gold coatings which reduce wear but avoid the pollution associated with conventional additives. Here we report production of large area gold nitride films on silicon substrates, using reactive ion sputtering and plasma etching, without the need for ultrahigh vacuum. Nanoindentation data show that gold nitride films have a hardness ∼50% greater than that of pure gold. These results are important for large-scale applications of gold nitride in coatings and electronics

  14. International survey of seat belt use exemptions.

    Science.gov (United States)

    Weiss, H; Sirin, H; Levine, J A; Sauber, E

    2006-08-01

    Substantial evidence of seatbelt efficacy has been shown by several studies, and it is widely recommended that motor vehicle occupants use properly fitted seat belts. However, some (but a heretofore unknown number of) countries with national seat belt laws permit various exemptions which may lower use rates. The aim of this study was to survey the variety of exemptions to national seat belt laws. This investigation relied on identifying respondents from national traffic safety agencies, other governmental and non-governmental organizations, Internet searches, personal contacts, and other sources. Questionnaires were deployed through a web based survey supplemented by email and postal versions. Responses were received from 30 countries of which 28 (93.7%) had a national seat belt law. About two thirds (63.7%) of the 28 national laws applied to both front and back seat passengers. The leading exemption types included vehicles made before a certain year (n = 13), antique vehicles (n = 12), military vehicles (n = 11), buses (n = 9), and emergency vehicles (n = 8). Most responding countries reported one or more specific categories of individuals as exempt including those with medical exemptions (n = 20), taxi drivers (n = 11), police (n = 9), emergency medical personnel (n = 8), physically disabled people (n = 6), and pregnant women (n = 6). Out of 26 responses to the question regarding current level of enforcement, 42.3% felt enforcement was "very good or good" and 57.7% characterized it as "fair or poor". This study represents one of the largest international traffic law surveys reported. Most national seatbelt laws offer perilous exemptions to a broad array of vehicle types and road user groups. These findings, coupled with concern over the level of enforcement in the majority of countries surveyed, suggest that international road safety efforts have a long way to go to improve coverage and enforcement of national seat belt laws.

  15. Activated carbons and gold

    International Nuclear Information System (INIS)

    McDougall, G.J.; Hancock, R.D.

    1980-01-01

    The literature on activated carbon is reviewed so as to provide a general background with respect to the effect of source material and activation procedure on carbon properties, the structure and chemical nature of the surface of the activated carbon, and the nature of absorption processes on carbon. The various theories on the absorption of gold and silver from cyanide solutions are then reviewed, followed by a discussion of processes for the recovery of gold and silver from cyanide solutions using activated carbon, including a comparison with zinc precipitation

  16. VERO cells harbor a poly-ADP-ribose belt partnering their epithelial adhesion belt

    Directory of Open Access Journals (Sweden)

    Laura Lafon-Hughes

    2014-10-01

    Full Text Available Poly-ADP-ribose (PAR is a polymer of up to 400 ADP-ribose units synthesized by poly-ADP-ribose-polymerases (PARPs and degraded by poly-ADP-ribose-glycohydrolase (PARG. Nuclear PAR modulates chromatin compaction, affecting nuclear functions (gene expression, DNA repair. Diverse defined PARP cytoplasmic allocation patterns contrast with the yet still imprecise PAR distribution and still unclear functions. Based on previous evidence from other models, we hypothesized that PAR could be present in epithelial cells where cadherin-based adherens junctions are linked with the actin cytoskeleton (constituting the adhesion belt. In the present work, we have examined through immunofluorescence and confocal microscopy, the subcellular localization of PAR in an epithelial monkey kidney cell line (VERO. PAR was distinguished colocalizing with actin and vinculin in the epithelial belt, a location that has not been previously reported. Actin filaments disruption with cytochalasin D was paralleled by PAR belt disruption. Conversely, PARP inhibitors 3-aminobenzamide, PJ34 or XAV 939, affected PAR belt synthesis, actin distribution, cell shape and adhesion. Extracellular calcium chelation displayed similar effects. Our results demonstrate the existence of PAR in a novel subcellular localization. An initial interpretation of all the available evidence points towards TNKS-1 as the most probable PAR belt architect, although TNKS-2 involvement cannot be discarded. Forthcoming research will test this hypothesis as well as explore the existence of the PAR belt in other epithelial cells and deepen into its functional implications.

  17. Dynamics Analysis and Modeling of Rubber Belt in Large Mine Belt Conveyors

    Directory of Open Access Journals (Sweden)

    Gao Yang

    2014-10-01

    Full Text Available Rubber belt not only is one of the key components of belt conveyor, but also affects the overall performance of the core part. Research on dynamics analysis of large conveyor not only helps to improve the reliability and design level, but also can guide the rational selection of conveyor safety factor, and effectively reduce the cost of the conveyor belt. Based on unique viscoelastic properties of belt conveyor, it was simplified as one-dimensional viscoelastic rod in this study, and then a discrete element model of conveyor systems was established. The kinetic equations of each discrete unit was derived using kinetic energy, potential energy of driving segment, bearing segment and return segment and equation of energy dissipation and Lagrange equation. Based on Wilson-q algorithm, the kinetic equation of DT1307-type ST2000's conveyor belt was solved by using Matlab to write computer programs. Research on the change rule of conveyor displacement, velocity, acceleration and dynamic tension during the boot process revealed the working mechanism of nonlinear viscoelastic, which lay the theoretical foundation for dynamic performance optimization of large belt conveyor. The calculation results were used to optimize design and analysis of conveyor system, the result showed that it could reduce the driven tension peaks about 12 %, save 5 % of overall manufacturing cost, which bring considerable profits for enterprises.

  18. Determination of relative immobile and sliding areas between carrying and tractive belts in using of belt conveyor intermediate drives

    OpenAIRE

    Goncharov K.A.

    2015-01-01

    Method of determination of relative immobile and sliding areas between carrying and tractive belts in places of mount-ing of belt conveyor intermediate drives made in the form of tractive contours is proposed. The example shows potential of this method in multidrive belt conveyor design process.

  19. Determination of relative immobile and sliding areas between carrying and tractive belts in using of belt conveyor intermediate drives

    Directory of Open Access Journals (Sweden)

    Goncharov K.A.

    2015-12-01

    Full Text Available Method of determination of relative immobile and sliding areas between carrying and tractive belts in places of mount-ing of belt conveyor intermediate drives made in the form of tractive contours is proposed. The example shows potential of this method in multidrive belt conveyor design process.

  20. THE NEOPROTEROZOIC ISLAND-ARC ASSOCIATION OF THE MUKODEK GOLD-ORE FIELD, NORTHERN BAIKAL AREA

    Directory of Open Access Journals (Sweden)

    V. A. Vanin

    2014-01-01

    Full Text Available Metamorphosed volcanic rocks of the Ushmukan suite were studied in the Mukodek gold-ore field located in the Baikal-Muya belt in the Northern Baikal area, Russia. The Ushmukan suite shows interleaving of ortoschists which compositions are widely variable. Basalt-andesite-dacite series of normal alkalinity are the substrate of the studied metavolcanic rocks. Based on the set of geochemical characteristics, it is concluded that the rocks were formed in suprasubduction geodynamic conditions corresponding to a mature island arc. The proximity of the geological locations and the similarity of the geochemical characteristics of the volcanic rocks of the Ushmukan suite and rocks of the Kelyan suite (Neoproterozoic, 823 Ma, which have similar compositions, give grounds to consider these two rock suites as age peers. Specific features of gold distribution through the Mukodek gold-ore field are analyzed. Industrial gold contents are recorded only in berezite-listvenite metasomatic rocks of the gold-quartz-sulfide formation which were formed on metavolcanic rocks of the Ushmukan suite. It is concluded that the volcanic rocks, which are specific of the island-arc setting, could be a source of gold for deposits in the Mukodek gold-ore field. 

  1. Method of monitoring, inspecting or testing conveyor belts

    International Nuclear Information System (INIS)

    Van der Walt, A.J.

    1985-01-01

    An invention is discussed which provides a method, installation and kit for monitoring, inspecting or testing a conveyor belt. Provision is made to transmit penetrating rays such as X-rays through a moving conveyor belt, forming a visible moving image from rays transmitted through the belt, and visually inspecting such moving image, after recording it if desired, to ascertain the condition of the interior of the belt. Typically an X-ray tube head is used to transmit the rays through the belt to a fluorescent screen which forms the image. The moving image can be recorded by means of a video camera

  2. ['Gold standard', not 'golden standard'

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2005-01-01

    In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same

  3. Spectroscopic diagnostic of gold plasma

    International Nuclear Information System (INIS)

    Busquet, M.

    1986-01-01

    Results of a simulation of a gold-aluminium alloy target irradiated by laser are presented. FCI code has been used with a processing out of LTE of atomic physics of gold and of multigroup photonics. Emission and reabsorption of gold and aluminium lines are included [fr

  4. Spectroscopic diagnostic of gold plasma

    Energy Technology Data Exchange (ETDEWEB)

    Busquet, M.

    1986-06-01

    Results of a simulation of a gold-aluminium alloy target irradiated by laser are presented. FCI code has been used with a processing out of LTE of atomic physics of gold and of multigroup photonics. Emission and reabsorption of gold and aluminium lines are included.

  5. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  6. Bioassisted Phytomining of Gold

    Science.gov (United States)

    Maluckov, Biljana S.

    2015-05-01

    Bioassisted phytomining implies targeted use of microorganisms and plants for the selective recovery of the metal. Metals from undissolved compounds are dissolved by applying specially chosen microorganisms and therefore become available to the hyperaccumulating plants. In the article, the selective extraction method of base metals and the precious metal gold by using microorganisms and plants is discussed.

  7. Digging for Gold

    Science.gov (United States)

    Waters, John K.

    2012-01-01

    In the case of higher education, the hills are more like mountains of data that "we're accumulating at a ferocious rate," according to Gerry McCartney, CIO of Purdue University (Indiana). "Every higher education institution has this data, but it just sits there like gold in the ground," complains McCartney. Big Data and the new tools people are…

  8. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  9. Gold Nanoparticle Microwave Synthesis

    International Nuclear Information System (INIS)

    Krantz, Kelsie E.; Christian, Jonathan H.; Coopersmith, Kaitlin; Washington II, Aaron L.; Murph, Simona H.

    2016-01-01

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  10. Plasmonic non-concentric nanorings array as an unidirectional nano-optical conveyor belt actuated by polarization rotation.

    Science.gov (United States)

    Jiang, Min; Wang, Guanghui; Jiao, Wenxiang; Ying, Zhoufeng; Zou, Ningmu; Ho, Ho-Pui; Sun, Tianyu; Zhang, Xuping

    2017-01-15

    We report a nano-optical conveyor belt containing an array of gold plasmonic non-concentric nanorings (PNNRs) for the realization of trapping and unidirectional transportation of nanoparticles through rotating the polarization of an excitation beam. The location of hot spots within an asymmetric plasmonic nanostructure is polarization dependent, thus making it possible to manipulate a trapped target by rotating the incident polarization state. In the case of PNNR, the two poles have highly unbalanced trap potential. This greatly enhances the chance of transferring trapped particles between adjacent PNNRs in a given direction through rotating the polarization. As confirmed by three-dimensional finite-difference time-domain analysis, an array of PNNRs forms an unidirectional nano-optical conveyor belt, which delivers target nanoparticles or biomolecules over a long distance with nanometer accuracy. With the capacity to trap and to transfer, our design offers a versatile scheme for conducting mechanical sample manipulation in many on-chip optofluidic applications.

  11. Gold and gold working in Late Bronze Age Northern Greece

    Science.gov (United States)

    Vavelidis, M.; Andreou, S.

    2008-04-01

    Numerous objects of gold displaying an impressive variety of types and manufacturing techniques are known from the Late Bronze Age (LBA) contexts of Mycenaean Greece, but very little is known about the origin and processing of gold during the second millennium b.c. Ancient literature and recent research indicate that northern Greece is probably the richest gold-bearing region in Greece, and yet, very little evidence exists regarding the exploitation of its deposits and the production as well as use of gold in the area during prehistory. The unusual find of a group of small stone crucibles at the prehistoric settlement of Thessaloniki Toumba, one with visible traces of gold melting, proves local production and offers a rare opportunity to examine the process of on-site gold working. Furthermore, the comparison of the chemical composition of prehistoric artefacts from two settlements with those of gold deposits in their immediate areas supports the local extraction of gold and opens up the prospect for some of the Mycenaean gold to have originated in northern Greece. The scarcity of gold items in northern Greek LBA contexts may not represent the actual amount of gold produced and consumed, but could be a result of the local social attitudes towards the circulation and deposition of artefacts from precious metals.

  12. Persistence of Salmonella on egg conveyor belts is dependent on the belt type but not on the rdar morphotype.

    Science.gov (United States)

    Stocki, S L; Annett, C B; Sibley, C D; McLaws, M; Checkley, S L; Singh, N; Surette, M G; White, A P

    2007-11-01

    Commercial caged layer flocks in Alberta, Canada, are commonly monitored for Salmonella enterica serovar Enteritidis (SE) and S. enterica serovar Typhimurium (ST) by environmental sampling. In one recent case, a SE strain isolated from the egg conveyor belt was a source of persistent infection for the flock. This study was undertaken to examine Salmonella colonization on egg conveyor belts and to determine whether the rdar morphotype, a conserved physiology associated with aggregation and long-term survival, contributed to persistence. Four woven belts constructed of natural or nonnatural fibers and a 1-piece belt made of vinyl were tested with rdar-positive ST and SE strains and a rdar-negative ST DeltaagfD reference strain. The type of egg belt was the most important factor influencing Salmonella colonization and persistence. The vinyl belt, with the least surface area available for colonization, had the fewest Salmonella remaining after washing and disinfection, whereas the hemp-plastic belt, with the greatest surface area, had the most Salmonella remaining. Real-time gene expression indicated that the rdar morphotype was involved in colonizing the egg belt pieces; however, it was not essential for persistence. In addition, rdar-positive and rdar-negative strains were equally similarly to disinfection on the egg belt pieces. The results indicate that Salmonella can persist on a variety of egg belts by mechanisms other than the rdar morphotype, and that using egg conveyer belts with reduced surface area for bacterial colonization can lessen contamination problems.

  13. Moessbauerspectroscopy on Gold Ruby Glass

    International Nuclear Information System (INIS)

    Haslbeck, S.

    2005-01-01

    In this thesis, the chemical states of gold and the physical mechanisms of the growing process of the particles under the influence of additional ingredients like tin, lead, antimony and selenium before, during and after the colouring process are investigated by using the Moessbauer spectroscopy on 197 Au, 119 Sn and 121 Sb, optical spectroscopy and X-ray-diffraction. Gold in an unnealed, colourless state of the glasses consists of monovalent forming linear bonds to two neighbouring oxygen atoms. The Lamb-Moessbauer factor of these gold oxide bondings is observed as 0.095 at 4.2 K. The gold in it's oxide state transforms to gold particles with a diameter of 3 nm to 60 nm. The size of the gold particles is quite definable within the optical spectra and certain sizes are also discernable within the Moessbauer spectra. One component of the Moessbauer spectra is assigned to the surface layer of the gold particles. By comparing this surface component with the amount of the bulk metallic core, one can calculate the size of the gold particles. In the Moessbauer spectra of the colourless glass one also can find parts of bulk metallic gold. Investigations with X-ray diffraction show that these are gold particles with a diameter of 100 nm to 300 nm and therefore have no additional colouring effect within the visible spectrum. The Moessbauer spectra on gold of the remelt glasses are similar to those which have been measured on the initial colourless glasses

  14. For the love of gold

    International Nuclear Information System (INIS)

    Young, J.E.

    1993-01-01

    Gold is found in minute quantities and gold mining generates enormous amounts of waste materials and long history of environmental destruction: mercury in tailing, eroded land, and acid mine drainage are legacies of the past. The problem has become worse in recent years in North America, Australia, the Amazon basin, Philippines. This paper describes the economics of gold and the changes in the world economy which has precipitated the new gold rushes. Current technology uses a cyanide solution for leaching small amounts of gold from tons of waste, and mercury remains a toxic waste of gold mining. Both short and long term results of gold mining, on the environment and on indiginous populations are described

  15. Alien Asteroid Belt Compared to our Own

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1: Band of Light Comparison This artist's concept illustrates what the night sky might look like from a hypothetical alien planet in a star system with an asteroid belt 25 times as massive as the one in our own solar system (alien system above, ours below; see Figure 1). NASA's Spitzer Space Telescope found evidence for such a belt around the nearby star called HD 69830, when its infrared eyes spotted dust, presumably from asteroids banging together. The telescope did not find any evidence for a planet in the system, but astronomers speculate one or more may be present. The movie begins at dusk on the imaginary world, when HD 69830, like our Sun, has begun to set over the horizon. Time is sped up to show the onset of night and the appearance of a brilliant band of light. This light comes from dust in a massive asteroid belt, which scatters sunlight. In our solar system, anybody observing the skies on a moonless night far from city lights can see the sunlight that is scattered by dust in our asteroid belt. Called zodiacal light and sometimes the 'false dawn,' this light appears as a dim band stretching up from the horizon when the Sun is about to rise or set. The light is faint enough that the disk of our Milky Way galaxy remains the most prominent feature in the sky. (The Milky Way disk is shown perpendicular to the zodiacal light in both pictures.) In contrast, the zodiacal light in the HD 69830 system would be 1,000 times brighter than our own, outshining even the Milky Way.

  16. Drivers' attitudes toward front or rear child passenger belt use and seat belt reminders at these seating positions.

    Science.gov (United States)

    Kidd, David G; McCartt, Anne T

    2014-01-01

    Passengers, especially those in rear seating positions, use seat belts less frequently than drivers. In-vehicle technology can inform drivers when their passengers are unbuckled and encourage passengers to use belts. The current study collected information about drivers' attitudes toward passenger belt use and belt reminders for front passengers and children in back seats. A national telephone survey of 1218 people 18 and older was conducted, of which 477 respondents were drivers who transport a front seat passenger at least once a week and 254 were drivers who transport an 8- to 15-year-old child in the back seat. Respondents were asked about their attitudes toward belt use by their front passengers or rear child passengers and preferences for different passenger belt reminder features. Ninety percent of drivers who regularly transport front seat passengers said that the passengers always use seat belts. Reported belt use was even higher among 8- to 15-year-old children in the back seat (97%). Among the drivers whose children do not always buckle up, about half said their child unbuckled the belt during the trip. Almost every full-time belt use driver (96%) would encourage front passengers to buckle up if not belted, compared to 57 percent of part-time belt users and nonusers. In contrast, nearly every driver who transports children in the back seat would encourage their belt use, regardless of the driver's belt use habits. Most drivers who transport front passengers wanted passenger belt reminders to encourage passengers to buckle up. Most of these drivers wanted a chime/buzzer or warning light or text display and wanted the reminder to last indefinitely. Most drivers who transport child passengers in the rear seat wanted the vehicle to indicate whether child passengers are unbuckled. A large majority of these drivers wanted notifications via a visual diagram of seating positions and belt use, a chime/buzzer, and a warning light or text display. These drivers

  17. Understanding quaternions and the Dirac belt trick

    International Nuclear Information System (INIS)

    Staley, Mark

    2010-01-01

    The Dirac belt trick is often employed in physics classrooms to show that a 2π rotation is not topologically equivalent to the absence of rotation whereas a 4π rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors has been achieved, or if the trick is just an amusing analogy. The goal of this paper is to demystify the belt trick and to show that it suggests an underlying four-dimensional parameter space for rotations that is simply connected. An investigation into the geometry of this four-dimensional space leads directly to the system of quaternions, and to an interpretation of three-dimensional vectors as the generators of rotations in this larger four-dimensional world. The paper also shows why quaternions are the natural extension of complex numbers to four dimensions. The level of the paper is suitable for undergraduate students of physics.

  18. The atmospheric implications of radiation belt remediation

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2006-08-01

    Full Text Available High altitude nuclear explosions (HANEs and geomagnetic storms can produce large scale injections of relativistic particles into the inner radiation belts. It is recognised that these large increases in >1 MeV trapped electron fluxes can shorten the operational lifetime of low Earth orbiting satellites, threatening a large, valuable population. Therefore, studies are being undertaken to bring about practical human control of the radiation belts, termed "Radiation Belt Remediation" (RBR. Here we consider the upper atmospheric consequences of an RBR system operating over either 1 or 10 days. The RBR-forced neutral chemistry changes, leading to NOx enhancements and Ox depletions, are significant during the timescale of the precipitation but are generally not long-lasting. The magnitudes, time-scales, and altitudes of these changes are no more significant than those observed during large solar proton events. In contrast, RBR-operation will lead to unusually intense HF blackouts for about the first half of the operation time, producing large scale disruptions to radio communication and navigation systems. While the neutral atmosphere changes are not particularly important, HF disruptions could be an important area for policy makers to consider, particularly for the remediation of natural injections.

  19. The atmospheric implications of radiation belt remediation

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2006-08-01

    Full Text Available High altitude nuclear explosions (HANEs and geomagnetic storms can produce large scale injections of relativistic particles into the inner radiation belts. It is recognised that these large increases in >1 MeV trapped electron fluxes can shorten the operational lifetime of low Earth orbiting satellites, threatening a large, valuable population. Therefore, studies are being undertaken to bring about practical human control of the radiation belts, termed "Radiation Belt Remediation" (RBR. Here we consider the upper atmospheric consequences of an RBR system operating over either 1 or 10 days. The RBR-forced neutral chemistry changes, leading to NOx enhancements and Ox depletions, are significant during the timescale of the precipitation but are generally not long-lasting. The magnitudes, time-scales, and altitudes of these changes are no more significant than those observed during large solar proton events. In contrast, RBR-operation will lead to unusually intense HF blackouts for about the first half of the operation time, producing large scale disruptions to radio communication and navigation systems. While the neutral atmosphere changes are not particularly important, HF disruptions could be an important area for policy makers to consider, particularly for the remediation of natural injections.

  20. Araguaia fold belt, new geochronological data

    International Nuclear Information System (INIS)

    Lafon, J.M.; Macambira, J.B.; Macambira, M.J.B.; Moura, C.A.V.; Souza, A.C.C.

    1990-01-01

    The northern part of the Araguaia Fold Belt (AFB) outcrops in a N-S direction for about 400 km in the state of Tocantins. Dome-like structures occur in this fold belt also in a N-S direction. Both deformation and metamorphism increase from the West to the East. The basement of the AFB consist of Colmeia complex and Cantao gneiss, which crop out mainly in the core of the dome-like structures. The supracrustals rocks of the fold belt belongs to the Baixo Araguaia supergroup which is divided into the lower Estrondo group and the upper Tocantins group. Preliminary Sm-Nd data from the Colmeia complex (Grota Rica dome) gave Archean model ages of 2.8 Ga (TNd sub(DM)) while Rb-Sr data in the same rocks give an age of 2530 ± 200 Ma. In the others dome-like structures, the Rb-Sr systematics gave ages for the Colmeia a complex of 2239 ± 47 Ma (Colmeia structure) and 1972 ± 46 Ma (Lontra structure). These younger ages are believed to represent partial to total isotopic resetting of the Rb-Sr system during the Transamazonian Event. The Rb-Sr studies of the Cantao gneiss gave an age of 1774 ± 31 Ma. (author)

  1. A special issue devoted to gold deposits in northern Nevada: Part 2. Carlin-type Deposits

    Science.gov (United States)

    Hofstra, Albert H.; John, David A.; Theodore, Ted G.

    2003-01-01

    This is the second of two special issues of Economic Geology devoted to gold deposits in northern Nevada. Readers interested in a general overview of these deposits, their economic significance, their context within the tectonic evolution of the region, and synoptic references on each gold deposit type are directed to the preface of the first special issue (John et al., 2003). Volume 98, issue 2, contains five papers that address regional aspects important to the genesis of gold deposits in northern Nevada and five papers that present detailed studies of epithermal deposits and districts. All of the regional papers are pertinent to Carlin-type gold deposits, because they address the age of mineralization (Arehart et al., 2003), origin and evolutionary history of the northwest-striking mineral belts that localize many deposits (Grauch et al., 2003), nature of the middle and lower crust below these mineral belts (Howard, 2003), district- to deposit-scale stream sediment and lithogeochemical anomalies (Theodore et al., 2003), and stratigraphy and structure of a district located along a northeast-striking lineament (Peters et al., 2003).

  2. Rushing for gold

    DEFF Research Database (Denmark)

    Jønsson, Jesper Bosse; Bryceson, Deborah Fahy

    2009-01-01

    African rural dwellers have faced depressed economic prospects for several decades. Now, in a number of mineral-rich countries, multiple discoveries of gold and precious stones have attracted large numbers of prospective small-scale miners. While their 'rush' to, and activities within, mining sit...... affluent than the others, suggesting that movement can be rewarding for those willing to 'try their luck' with the hard work and social networking demands of mining another site.......African rural dwellers have faced depressed economic prospects for several decades. Now, in a number of mineral-rich countries, multiple discoveries of gold and precious stones have attracted large numbers of prospective small-scale miners. While their 'rush' to, and activities within, mining sites...

  3. Gold' 82 - technical sessions

    International Nuclear Information System (INIS)

    Viewing, K.

    1983-01-01

    Sulphur-isotope studies had been applied by Dr. I. Lambert to a number of deposits in Western Australia and also to certain samples from Vubachickwe and other deposits in Zimbabwe. A study of the sulphur isotopes at the Dickenson Mine, revealed a wide spread of values in the mineralised zones. Metamorphic processes were likely to be significant in the concentration of gold. The iron formations at the Old Jardine Mine had been unfolded by Dr. W.S. Hallager and the pattern of sedimentation was unraveled. A gold-rich zone was separated by a barren gap from the other part of the mineralised zone. Research was also done on the effects of the metamorphic processes, and the ages of mineralisation

  4. Aortic ruptures in seat belt wearers.

    Science.gov (United States)

    Arajärvi, E; Santavirta, S; Tolonen, J

    1989-09-01

    Several investigations have indicated that rupture of the thoracic aorta is one of the leading causes of immediate death in victims of road traffic accidents. In Finland in 1983, 92% of front-seat passengers were seat belt wearers on highways and 82% in build-up areas. The mechanisms of rupture of the aorta have been intensively investigated, but the relationship between seat belt wearing and injury mechanisms leading to aortic rupture is still largely unknown. This study comprises 4169 fatally injured victims investigated by the Boards of Traffic Accident Investigation of Insurance Companies during the period 1972 to 1985. Chest injuries were recorded as the main cause of death in 1121 (26.9%) victims, 207 (5.0%) of those victims having worn a seat belt. Aortic ruptures were found at autopsy in 98 victims and the exact information of the location of the aortic tears was available in 68. For a control group, we analyzed 72 randomly chosen unbelted victims who had a fatal aortic rupture in similar accidents. The location of the aortic rupture in unbelted victims was more often in the ascending aorta, especially in drivers, whereas in seat belt wearers the distal descending aorta was statistically more often ruptured, especially in right-front passengers (p less than 0.05). The steering wheel predominated statistically as the part of the car estimated to have caused the injury in unbelted victims (37/72), and some interior part of the car was the most common cause of fatal thoracic impacts in seat belt wearers (48/68) (p less than 0.001). The mechanism of rupture of the aorta in the classic site just distal to the subclavian artery seems to be rapid deceleration, although complex body movements are also responsible in side impact collisions. The main mechanism leading to rupture of the ascending aorta seems to be severe blow to the bony thorax. This also often causes associated thoracic injuries, such as heart rupture and sternal fracture. Injuries in the ascending

  5. Radioactive gold ring dermatitis

    International Nuclear Information System (INIS)

    Miller, R.A.; Aldrich, J.E.

    1990-01-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy

  6. Radiation Belts of Antiparticles in Planetary Magnetospheres

    Science.gov (United States)

    Pugacheva, G. I.; Gusev, A. A.; Jayanthi, U. B.; Martin, I. M.; Spjeldvik, W. N.

    2007-05-01

    The Earth's radiation belts could be populated, besides with electrons and protons, also by antiparticles, such as positrons (Basilova et al., 1982) and antiprotons (pbar). Positrons are born in the decay of pions that are directly produced in nuclear reactions of trapped relativistic inner zone protons with the residual atmosphere at altitudes in the range of about 500 to 3000 km over the Earth's surface. Antiprotons are born by high energy (E > 6 GeV) cosmic rays in p+p - p+p+p+ pbar and in p+p - p+p+n+nbar reactions. The trapping and storage of these charged anti-particles in the magnetosphere result in radiation belts similar to the classical Van Allen belts of protons and electrons. We describe the mathematical techniques used for numerical simulation of the trapped positron and antiproton belt fluxes. The pion and antiproton yields were simulated on the basis of the Russian nuclear reaction computer code MSDM, a Multy Stage Dynamical Model, Monte Carlo code, (i.e., Dementyev and Sobolevsky, 1999). For estimates of positron flux there we have accounted for ionisation, bremsstrahlung, and synchrotron energy losses. The resulting numerical estimates show that the positron flux with energy >100 MeV trapped into the radiation belt at L=1.2 is of the order ~1000 m-2 s-1 sr-1, and that it is very sensitive to the shape of the trapped proton spectrum. This confined positron flux is found to be greater than that albedo, not trapped, mixed electron/positron flux of about 50 m-2 s-1 sr-1 produced by CR in the same region at the top of the geomagnetic field line at L=1.2. As we show in report, this albedo flux also consists mostly of positrons. The trapped antiproton fluxes produced by CR in the Earth's upper rarified atmosphere were calculated in the energy range from 10 MeV to several GeV. In the simulations we included a mathematic consideration of the radial diffusion process, both an inner and an outer antiproton source, losses of particles due to ionization process

  7. Granulite belts of Central India with special reference to the Bhopalpatnam Granulite Belt: Significance in crustal evolution and implications for Columbia supercontinent

    Science.gov (United States)

    Vansutre, Sandeep; Hari, K. R.

    2010-11-01

    The Central Indian collage incorporates the following major granulite belts: (1) the Balaghat-Bhandara Granulite Belt (BBG), (2) the Ramakona-Katangi Granulite Belt (RKG), (3) the Chhatuabhavna Granulite (CBG) of Bilaspur-Raigarh Belt, (4) the Makrohar Granulite Belt (MGB) of Mahakoshal supracrustals, (5) the Kondagaon Granulite Belt (KGGB), (6) the Bhopalpatnam Granulite Belt (BGB), (7) the Konta Granulite Belt (KTGB) and (8) the Karimnagar Granulite Belt (KNGB) of the East Dharwar Craton (EDC). We briefly synthesize the general geologic, petrologic and geochronologic features of these belts and explain the Precambrian crustal evolution in Central India. On the basis of the available data, a collisional relationship between Bastar craton and the EDC during the Paleo-Mesoproterozoic is reiterated as proposed by the earlier workers. The tectonic evolution of only few of the orogenic belts (BGB in particular) of Central India is related to Columbia.

  8. Belt conveyor dynamics in transient operation for speed control

    OpenAIRE

    He, D.; Pang, Y.; Lodewijks, G.

    2016-01-01

    Belt conveyors play an important role in continuous dry bulk material transport, especially at the mining industry. Speed control is expected to reduce the energy consumption of belt conveyors. Transient operation is the operation of increasing or decreasing conveyor speed for speed control. According to literature review, current research rarely takes the conveyor dynamics in transient operation into account. However, in belt conveyor speed control, the conveyor dynamic behaviors are signifi...

  9. Seat Belt Use Intention among Brazilian Undergraduate Students

    OpenAIRE

    TORQUATO, RENATA; FRANCO, CLÁUDIO M. A; BIANCHI, ALESSANDRA

    2012-01-01

    The objectives of this study were to explore self-reported seat belt use and group differences in different scenarios in a Brazilian sample and research the variables related to it. 120 college students answered a questionnaire with variables from the theory of planned behavior in order to evaluate the intention of seat belt use among car occupants. Results indicated that attitude and intention were the variables that most contributed to explaining seat belt use. Intention was highly correlat...

  10. Health Monitoring for Coated Steel Belts in an Elevator System

    Directory of Open Access Journals (Sweden)

    Huaming Lei

    2012-01-01

    Full Text Available This paper presents a method of health monitoring for coated steel belts in an elevator system by measuring the electrical resistance of the ropes embedded in the belt. A model on resistance change caused by fretting wear and stress fatigue has been established. Temperature and reciprocating cycles are also taken into consideration when determining the potential strength degradation of the belts. It is proved by experiments that the method could effectively estimate the health degradation of the most dangerous section as well as other ones along the whole belts.

  11. Colors of Inner Disk Classical Kuiper Belt Objects

    Science.gov (United States)

    Romanishin, W.; Tegler, S. C.; Consolmagno, G. J.

    2010-07-01

    We present new optical broadband colors, obtained with the Keck 1 and Vatican Advanced Technology telescopes, for six objects in the inner classical Kuiper Belt. Objects in the inner classical Kuiper Belt are of interest as they may represent the surviving members of the primordial Kuiper Belt that formed interior to the current position of the 3:2 resonance with Neptune, the current position of the plutinos, or, alternatively, they may be objects formed at a different heliocentric distance that were then moved to their present locations. The six new colors, combined with four previously published, show that the ten inner belt objects with known colors form a neutral clump and a reddish clump in B-R color. Nonparametric statistical tests show no significant difference between the B-R color distribution of the inner disk objects compared to the color distributions of Centaurs, plutinos, or scattered disk objects. However, the B-R color distribution of the inner classical Kuiper Belt Objects does differ significantly from the distribution of colors in the cold (low inclination) main classical Kuiper Belt. The cold main classical objects are predominately red, while the inner classical belt objects are a mixture of neutral and red. The color difference may reveal the existence of a gradient in the composition and/or surface processing history in the primordial Kuiper Belt, or indicate that the inner disk objects are not dynamically analogous to the cold main classical belt objects.

  12. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    Science.gov (United States)

    Barclay, John A.; Stewart, Walter F.; Henke, Michael D.; Kalash, Kenneth E.

    1987-01-01

    A magnetic refrigerator operating in the 12 to 77K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  13. Design of belt conveyors in bulk terminal applications. Part II

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, P J; Ramos, C M

    1986-04-01

    The main design parameters used for belt conveyors in harbour applications are discussed. Conveyor belting including the carcass, belt cover, belt tension and speed, and safety factors, idlers, conveyor pulleys, motors, fluid couplings and drive arrangements are considered. Technical factors are briefly outlined for the designer to consider to achieve minimum acceptable component service life. A method is discussed to reduce coal degradation investigated using a test chute designed for the purpose of minimizing sized coal degradation at transfer points in the refurbishing of the Durban Coal Terminal. 24 references.

  14. COLORS OF INNER DISK CLASSICAL KUIPER BELT OBJECTS

    International Nuclear Information System (INIS)

    Romanishin, W.; Tegler, S. C.; Consolmagno, G. J.

    2010-01-01

    We present new optical broadband colors, obtained with the Keck 1 and Vatican Advanced Technology telescopes, for six objects in the inner classical Kuiper Belt. Objects in the inner classical Kuiper Belt are of interest as they may represent the surviving members of the primordial Kuiper Belt that formed interior to the current position of the 3:2 resonance with Neptune, the current position of the plutinos, or, alternatively, they may be objects formed at a different heliocentric distance that were then moved to their present locations. The six new colors, combined with four previously published, show that the ten inner belt objects with known colors form a neutral clump and a reddish clump in B-R color. Nonparametric statistical tests show no significant difference between the B-R color distribution of the inner disk objects compared to the color distributions of Centaurs, plutinos, or scattered disk objects. However, the B-R color distribution of the inner classical Kuiper Belt Objects does differ significantly from the distribution of colors in the cold (low inclination) main classical Kuiper Belt. The cold main classical objects are predominately red, while the inner classical belt objects are a mixture of neutral and red. The color difference may reveal the existence of a gradient in the composition and/or surface processing history in the primordial Kuiper Belt, or indicate that the inner disk objects are not dynamically analogous to the cold main classical belt objects.

  15. Immunological properties of gold nanoparticles.

    Science.gov (United States)

    Dykman, Lev A; Khlebtsov, Nikolai G

    2017-03-01

    In the past decade, gold nanoparticles have attracted strong interest from the nanobiotechnological community owing to the significant progress made in robust and easy-to-make synthesis technologies, in surface functionalization, and in promising biomedical applications. These include bioimaging, gene diagnostics, analytical sensing, photothermal treatment of tumors, and targeted delivery of various biomolecular and chemical cargos. For the last-named application, gold nanoparticles should be properly fabricated to deliver the cargo into the targeted cells through effective endocytosis. In this review, we discuss recent progress in understanding the selective penetration of gold nanoparticles into immune cells. The interaction of gold nanoparticles with immune cell receptors is discussed. As distinct from other published reviews, we present a summary of the immunological properties of gold nanoparticles. This review also summarizes what is known about the application of gold nanoparticles as an antigen carrier and adjuvant in immunization for the preparation of antibodies in vivo . For each of the above topics, the basic principles, recent advances, and current challenges are discussed. Thus, this review presents a detailed analysis of data on interaction of gold nanoparticles with immune cells. Emphasis is placed on the systematization of data over production of antibodies by using gold nanoparticles and adjuvant properties of gold nanoparticles. Specifically, we start our discussion with current data on interaction of various gold nanoparticles with immune cells. The next section describes existing technologies to improve production of antibodies in vivo by using gold nanoparticles conjugated with specific ligands. Finally, we describe what is known about adjuvant properties of bare gold or functionalized nanoparticles. In the Conclusion section, we present a short summary of reported data and some challenges and perspectives.

  16. Earthquake activity along the Himalayan orogenic belt

    Science.gov (United States)

    Bai, L.; Mori, J. J.

    2017-12-01

    The collision between the Indian and Eurasian plates formed the Himalayas, the largest orogenic belt on the Earth. The entire region accommodates shallow earthquakes, while intermediate-depth earthquakes are concentrated at the eastern and western Himalayan syntaxis. Here we investigate the focal depths, fault plane solutions, and source rupture process for three earthquake sequences, which are located at the western, central and eastern regions of the Himalayan orogenic belt. The Pamir-Hindu Kush region is located at the western Himalayan syntaxis and is characterized by extreme shortening of the upper crust and strong interaction of various layers of the lithosphere. Many shallow earthquakes occur on the Main Pamir Thrust at focal depths shallower than 20 km, while intermediate-deep earthquakes are mostly located below 75 km. Large intermediate-depth earthquakes occur frequently at the western Himalayan syntaxis about every 10 years on average. The 2015 Nepal earthquake is located in the central Himalayas. It is a typical megathrust earthquake that occurred on the shallow portion of the Main Himalayan Thrust (MHT). Many of the aftershocks are located above the MHT and illuminate faulting structures in the hanging wall with dip angles that are steeper than the MHT. These observations provide new constraints on the collision and uplift processes for the Himalaya orogenic belt. The Indo-Burma region is located south of the eastern Himalayan syntaxis, where the strike of the plate boundary suddenly changes from nearly east-west at the Himalayas to nearly north-south at the Burma Arc. The Burma arc subduction zone is a typical oblique plate convergence zone. The eastern boundary is the north-south striking dextral Sagaing fault, which hosts many shallow earthquakes with focal depth less than 25 km. In contrast, intermediate-depth earthquakes along the subduction zone reflect east-west trending reverse faulting.

  17. The extractive metallurgy of gold

    Energy Technology Data Exchange (ETDEWEB)

    Kongolo, K.; Mwema, M.D. [University of Lubumbashi, Zaire, Gecamines Metallurgical Research Centre, Likasi, Zaire, c/o Gecamines Brussels (Belgium)

    1998-12-15

    Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied.

  18. The extractive metallurgy of gold

    Science.gov (United States)

    Kongolo, K.; Mwema, M. D.

    1998-12-01

    Mössbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Mössbauer spectroscopy could be applied.

  19. The extractive metallurgy of gold

    International Nuclear Information System (INIS)

    Kongolo, K.; Mwema, M.D.

    1998-01-01

    Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied

  20. Surface-stabilized gold nanocatalysts

    Science.gov (United States)

    Dai, Sheng [Knoxville, TN; Yan, Wenfu [Oak Ridge, TN

    2009-12-08

    A surface-stabilized gold nanocatalyst includes a solid support having stabilizing surfaces for supporting gold nanoparticles, and a plurality of gold nanoparticles having an average particle size of less than 8 nm disposed on the stabilizing surfaces. The surface-stabilized gold nanocatalyst provides enhanced stability, such as at high temperature under oxygen containing environments. In one embodiment, the solid support is a multi-layer support comprising at least a first layer having a second layer providing the stabilizing surfaces disposed thereon, the first and second layer being chemically distinct.

  1. Dust bands in the asteroid belt

    International Nuclear Information System (INIS)

    Sykes, M.V.; Greenberg, R.; Dermott, S.F.; Nicholson, P.D.; Burns, J.A.

    1989-01-01

    This paper describes the original IRAS observations leading to the discovery of the three dust bands in the asteroid belt and the analysis of data. Special attention is given to an analytical model of the dust band torus and to theories concerning the origin of the dust bands, with special attention given to the collisional equilibrium (asteroid family), the nonequilibrium (random collision), and the comet hypotheses of dust-band origin. It is noted that neither the equilibrium nor nonequilibrium models, as currently formulated, present a complete picture of the IRAS dust-band observations. 32 refs

  2. On a new component of radiation belts

    International Nuclear Information System (INIS)

    Grigorov, N.L.; Kurnosova, L.V.; Razorenov, L.A.; Remizov, A.S.; Fradkin, M.I.; Moskovskij Gosudarstvennyj Univ.

    1982-01-01

    The mechanism of electron radiation belt filling with high-energy particles is discussed. Experimental data on particle fluxes in the Earth magnetosphere are presented. The experiments are carried out using the Cherenkov scintillation telescope installed on the ''Lightning-1'' satellite. Values of secondary particle flux obtained during the measurement at a height of 500 km and 30-40 th. km. coincide within the limits of errors. It is noted that secondary particle flux, equal to the albedo electron flux, is registered on large heights. This reason indicates the fact of forbidden angle filling with electrons with energies above 10 MeV

  3. Linear Motor for Drive of Belt Conveyor

    Directory of Open Access Journals (Sweden)

    Milan Krasl

    2006-01-01

    Full Text Available This paper introduces a novel approach on the design of a linear motor for drive of belt conveyor (LMBC. The motor is a simple combination of asynchronous motor in plane. The electromagnetic forces is one of the most important parameters of electrical machines. This parameter is necessary for the checking of the design. This paper describes several variants: linear motor with slots in platens, slots in one half of platens and optimization of slots. The electromagnetic force can be found with the help of a Finite Elements Method – based program. For solution was used QuickField program.

  4. The Fort Smith radioactive belt, Northwest Territories

    International Nuclear Information System (INIS)

    Charbonneau, B.W.

    1980-01-01

    The Fort Smith Belt is an elongate zone, about 200 km x 50 km, extending from the East Arm of Great Slave Lake southerly into northeastern Alberta. The major feature of the belt is that it is one of the most radioactive regions so far recognized in the Canadian Shield. Potassium, uranium, and thorium are all enriched but the greatest increase is in thorium. The dominant rock type underlying the area is a foliated porphyritic granite. This rock contains an average of about 80 ppm thorium (with areas of tens of square kilometres containing up to 200 ppm) and approximately 11 ppm uranium. In places, dark elongate zones rich in biotite, apatite, and opaque minerals within the porphyritic granite may contain an order of magnitude more uranium and thorium than the porphyry. Radioactive minerals within both the porphyry and the dark zones are principally monazite (containing up to 16% ThO 2 ) and isolated grains of uraninite. This foliated porphyritic granite is interpreted as being pre- or syntectonic with respect to the Hudsonian event because its foliation parallels that of the surrounding rocks. There has been subsequent deformation. The second characteristic feature of the Fort Smith Belt is the development of a peripheral zone where eU is enriched relative to eTh correlating mainly with granitoid rocks which surround the thorium-rich area and wherein ratios of eU/eTh exceed 1:2 (compared to the crustal average of 1:4). Uranium may have moved laterally into this marginal area from the thorium-rich porphyry, possibly in a vapour phase. There is a possibility that concentrations of uranium as well as other metals such as Cu, Mo, Zn, Sn, and W could exist in the porphyry and its margin in appropriate chemical and/or structural traps. The radioactive granite rocks of the Fort Smith Belt are adjacent to uranium-thorium occurrences in the nearby Proterozoic Nonacho sediments but whether or not a genetic relationship exists between the two situations is uncertain. (auth)

  5. Belt, Road, and Circle: The Arctic and Northern Europe in China's Belt and Road Initiative

    DEFF Research Database (Denmark)

    Nørup Sørensen, Camilla Tenna

    2018-01-01

    Sørensen offers a much-needed analysis of the how the development of the Belt and Road Initiative (BRI) links to China’s growing interests and ambitions in the Arctic showing how China is using the BRI to further intensify and strengthen relations with the Nordic countries in the Arctic. Conducting...

  6. 31 CFR 100.4 - Gold coin and gold certificates in general.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Gold coin and gold certificates in... EXCHANGE OF PAPER CURRENCY AND COIN In General § 100.4 Gold coin and gold certificates in general. Gold coins, and gold certificates of the type issued before January 30, 1934, are exchangeable, as provided...

  7. Determining gold content

    International Nuclear Information System (INIS)

    Clayton, C.G.; Wormald, M.R.

    1981-01-01

    A method for determining the gold content of a material, comprises irradiating a body of the material with neutrons and determining the intensity of γ-rays having an energy of 279 keV arising from the reaction 179 Au(nn') 179 Au → 279 keV. The apparatus has means for conveying the materials past an assembly, which has a neutron source, which does not produce neutrons having sufficient energy to excite fast neutron reactions in non-auriferous constituents. (author)

  8. Turning lead into gold

    DEFF Research Database (Denmark)

    Jensen, Steffen Moltrup Ernø

    For years the field of entrepreneurship has been blinded by the alchemical promise of turning lead into gold, of finding the ones most likely to become the next Branson, Zuckerberg or Gates. The promise has been created in the midst of political and scientific agendas where certain individuals...... is not to accumulate state or market wealth, but for entrepreneurial skills to become tools towards the liberation of the individual from oppressive systems of control – essentially to add public value rather than economic value. In this presentation I will sketch an anarchist perspective on entrepreneurship, looking...

  9. Pelvic belt effects on sacroiliac joint ligaments: a computational approach to understand therapeutic effects of pelvic belts.

    Science.gov (United States)

    Sichting, Freddy; Rossol, Jerome; Soisson, Odette; Klima, Stefan; Milani, Thomas; Hammer, Niels

    2014-01-01

    The sacroiliac joint is a widely described source of low back pain. Therapeutic approaches to relieve pain include the application of pelvic belts. However, the effects of pelvic belts on sacroiliac joint ligaments as potential pain generators are mostly unknown. The aim of our study was to analyze the influence of pelvic belts on ligament load by means of a computer model. Experimental computer study using a finite element method. A computer model of the human pelvis was created, comprising bones, ligaments, and cartilage. Detailed geometries, material properties of ligaments, and in-vivo pressure distribution patterns of a pelvic belt were implemented. The effects of pelvic belts on ligament strain were computed in the double-leg stance. Pelvic belts increase sacroiliac joint motion around the sagittal axis but decrease motion around the transverse axis. With pelvic belt application, most of the strained sacroiliac joint ligaments were relieved, especially the sacrospinous, sacrotuberous, and the interosseous sacroiliac ligaments. Sacroiliac joint motion and ligament strains were minute. These results agree with validation data from other studies. Assigning homogenous and linear material properties and excluding muscle forces are clear simplifications of the complex reality. Pelvic belts alter sacroiliac joint motion and provide partial relief of ligament strain that is subjectively marked, although minimal in absolute terms. These findings confirm theories that besides being mechanical stabilizers, the sacroiliac joint ligaments are likely involved in neuromuscular feedback mechanisms. The results from our computer model help with unraveling the therapeutic mechanisms of pelvic belts.

  10. Determination of Gold from Gold Matrix of North Western Nigeria ...

    African Journals Online (AJOL)

    The research paper presents analytical results of Au, Mn and V concentrations of some Nigerian gold ores using two techniques: epithermal neutron activation analysis (ENAA) and proton induced X-ray emission (PIXE). Fourteen samples were collected from gold fields of North Western Nigeria, prepared separately to a ...

  11. HERSCHEL -RESOLVED OUTER BELTS OF TWO-BELT DEBRIS DISKS—EVIDENCE OF ICY GRAINS

    Energy Technology Data Exchange (ETDEWEB)

    Morales, F. Y.; Bryden, G.; Werner, M. W.; Stapelfeldt, K. R., E-mail: Farisa@jpl.nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2016-11-01

    We present dual-band Herschel /PACS imaging for 59 main-sequence stars with known warm dust ( T {sub warm} ∼ 200 K), characterized by Spitzer . Of 57 debris disks detected at Herschel wavelengths (70 and/or 100 and 160 μ m), about half have spectral energy distributions (SEDs) that suggest two-ring disk architectures mirroring that of the asteroid–Kuiper Belt geometry; the rest are consistent with single belts of warm, asteroidal material. Herschel observations spatially resolve the outer/cold dust component around 14 A-type and 4 solar-type stars with two-belt systems, 15 of which for the first time. Resolved disks are typically observed with radii >100 AU, larger than expected from a simple blackbody fit. Despite the absence of narrow spectral features for ice, we find that the shape of the continuum, combined with resolved outer/cold dust locations, can help constrain the grain size distribution and hint at the dust’s composition for each resolved system. Based on the combined Spitzer /IRS+Multiband Imaging Photometer (5-to-70 μ m) and Herschel /PACS (70-to-160 μ m) data set, and under the assumption of idealized spherical grains, we find that over half of resolved outer/cold belts are best fit with a mixed ice/rock composition. Minimum grain sizes are most often equal to the expected radiative blowout limit, regardless of composition. Three of four resolved systems around the solar-type stars, however, tend to have larger minimum grains compared to expectation from blowout ( f {sub MB} = a {sub min}/ a {sub BOS} ∼ 5). We also probe the disk architecture of 39 Herschel -unresolved systems by modeling their SEDs uniformly, and find them to be consistent with 31 single- and 8 two-belt debris systems.

  12. Mesin Pemindah Bahan : Studi Prestasi Belt Conveyor Hubungannya Dengan Ukuran Butiran Dan Tingkat Kelembaban Bahan Curah ( Batubara ), Panjang Belt 7,6 Meter ; Lebar 32 Centimeter

    OpenAIRE

    Nugroho, Rio

    2011-01-01

    Banyak industri yang menggunakan belt conveyor sebagai alat transportasi material, sebab punya banyak keuntungan. Sehingga, untuk meningkatkan performansi belt conveyor tersebut perlu dilakukan pengidentifikasian prestasi belt conveyor. Identifikasi dilakukan dengan material transfer batubara. Yang akan diamati adalah pengaruh ukuran butiran material dan tingkat kelembaban terhadap kapasitas transfer belt conveyor. Dari pengujian didapatkan kapasitas transfer terbesar adalah material batubar...

  13. Problems with models of the radiation belts

    International Nuclear Information System (INIS)

    Daly, E.J.; Lemaire, J.; Heynderickx, D.; Rodgers, D.J.

    1996-01-01

    The current standard models of the radiation-belt environment have many shortcomings, not the least of which is their extreme age. Most of the data used for them were acquired in the 1960's and early 1970's. Problems with the present models, and the ways in which data from more recent missions are being or can be used to create new models with improved functionality, are described. The phenomenology of the radiation belts, the effects on space systems, and geomagnetic coordinates and modeling are discussed. Errors found in present models, their functional limitations, and problems with their implementation and use are detailed. New modeling must address problems at low altitudes with the south Atlantic anomaly, east-west asymmetries and solar cycle variations and at high altitudes with the highly dynamic electron environment. The important issues in space environment modeling from the point of view of usability and relationship with effects evaluation are presented. New sources of data are discussed. Future requirements in the data, models, and analysis tools areas are presented

  14. Coordinates for Representing Radiation Belt Particle Flux

    Science.gov (United States)

    Roederer, Juan G.; Lejosne, Solène

    2018-02-01

    Fifty years have passed since the parameter "L-star" was introduced in geomagnetically trapped particle dynamics. It is thus timely to review the use of adiabatic theory in present-day studies of the radiation belts, with the intention of helping to prevent common misinterpretations and the frequent confusion between concepts like "distance to the equatorial point of a field line," McIlwain's L-value, and the trapped particle's adiabatic L* parameter. And too often do we miss in the recent literature a proper discussion of the extent to which some observed time and space signatures of particle flux could simply be due to changes in magnetospheric field, especially insofar as off-equatorial particles are concerned. We present a brief review on the history of radiation belt parameterization, some "recipes" on how to compute adiabatic parameters, and we illustrate our points with a real event in which magnetospheric disturbance is shown to adiabatically affect the particle fluxes measured onboard the Van Allen Probes.

  15. WATER ICE IN THE KUIPER BELT

    International Nuclear Information System (INIS)

    Brown, M. E.; Fraser, W. C.; Schaller, E. L.

    2012-01-01

    We examine a large collection of low-resolution near-infrared spectra of Kuiper Belt objects (KBOs) and centaurs in an attempt to understand the presence of water ice in the Kuiper Belt. We find that water ice on the surface of these objects occurs in three separate manners: (1) Haumea family members uniquely show surfaces of nearly pure water ice, presumably a consequence of the fragmentation of the icy mantle of a larger differentiated proto-Haumea; (2) large objects with absolute magnitudes of H < 3 (and a limited number to H = 4.5) have surface coverings of water ice—perhaps mixed with ammonia—that appears to be related to possibly ancient cryovolcanism on these large objects; and (3) smaller KBOs and centaurs which are neither Haumea family members nor cold-classical KBOs appear to divide into two families (which we refer to as 'neutral' and 'red'), each of which is a mixture of a common nearly neutral component and either a slightly red or very red component that also includes water ice. A model suggesting that the difference between neutral and red objects due to formation in an early compact solar system either inside or outside, respectively, of the ∼20 AU methanol evaporation line is supported by the observation that methanol is only detected on the reddest objects, which are those which would be expected to have the most of the methanol containing mixture.

  16. Activation analysis in gold industry

    International Nuclear Information System (INIS)

    Kist, A. A.

    2003-01-01

    Nuclear techniques and methods were, are, and will be very important for many fields of science, agriculture, industry, etc. Among other examples one can remember role of the nuclear medicine (radiotherapy and radiodiagnostic methods) or semiconductors (communication, computing, information, etc.) which industrial production has been on initial stage based on activation analysis. One of very illustrative examples is application of nuclear methods in gold industry. This is given by favorable nuclear properties of gold. Uzbekistan is one of the main producers of gold. Open-cast mining and hydro metallurgic extraction (using leaching by cyanide and sorption by ion-exchange resin) is the mostly used technology. The typical gold ores are sulfide and contain elevated concentration of As and Sb. That needs special technology of gold extraction. Importance of gold for Uzbekistan economy is a reason why for many years there are carried out studies concerning to gold production. These studies include also nuclear methods and their results are successfully used in gold industry. The present paper gives a brief overview for period of 25 years. For many reasons most of these studies were not published before completely. Despite some results are obtained decades ago we decided to present the overview as an example how nuclear methods can cover requirements of the whole process. We are trying to sort these studies according to methods and applications

  17. Energy saving for belt conveyors by speed control

    NARCIS (Netherlands)

    He, D.

    2017-01-01

    Belt conveyors are widely used in bulk solids handling and conveying systems. Considering the extensive use of belt conveyors, their operations involve a large amount of energy. Taking the relevant economic and social challenges into account, there is a strong demand for lowering the energy

  18. The physical imitation experiments of nuclear belt weight scaler

    International Nuclear Information System (INIS)

    Shi Qicun; Wang Mingqian; Sun Jinhua; Li Zhonghao

    1993-01-01

    The physical imitation experiments of the nuclear belt weight scaler (NBWS) were performed with a coal-loaded belt. The linearity, repetition and long-time stability; of the NBWS were measured. And the influence of pile shape, load bias and the composition of coal on weight calculation were studied

  19. Respiratory Belt Transducer Constructed Using a Singing Greeting Card Beeper

    Science.gov (United States)

    Bhaskar, Anand; Subramani, Selvam; Ojha, Rajdeep

    2013-01-01

    An article by Belusic and Zupancic described the construction of a finger pulse sensor using a singing greeting card beeper. These authors felt that this beeper made of piezoelectric material could be easily modified to function as a respiratory belt transducer to monitor respiratory movements. Commercially available respiratory belt transducers,…

  20. Crustal Deformation around Zhangjiakou-Bohai Seismically Active Belt

    Science.gov (United States)

    Jin, H.; Fu, G.; Kato, T.

    2011-12-01

    Zhangjiakou-Bohai belt is a seismically active belt located in Northern China around Beijing, the capital of China. Near such a belt many great earthquakes occurred in the past centuries (e.g. the 1976 Tanshan Ms7.8 earthquake, the 1998 Zhangbei Ms6.2 earthquake, etc). Chinese Government established dense permanent and regional Global Positioning System (GPS) stations in and near the area. We collected and analyzed all the GPS observation data between 1999 and 2009 around Zhangjiakou-Bohai seismic belt, and obtained velocities at 143 stations. At the same time we investigated Zhangjiakou-Bohai belt slip rate for three profiles from northwest to southeast, and constructed a regional strain field on the Zhangjiakou-Bohai seismic belt region by least-square collocation. Based on the study we found that: 1) Nowadays the Zhangjiakou-Bohai seismic belt is creeping with left-lateral slip rate of 2.0mm~2.4mm/a, with coupling depth of 35~50km; 2) In total, the slip and coupling depth of the northwestern seismic belt is less than the one of southeast side; 3) The maximum shear strain is about 3×10-8 at Beijing-Tianjin-Tangshan area.

  1. A belt charging system for the Vivitron - design, early results

    International Nuclear Information System (INIS)

    Helleboid, J.M.; Gaudiot, G.

    1990-10-01

    A specific belt charging system has been designed, built and assembled for the 35 MV Vivitron. 100 m long belt is used. Together with main features of the design, experimental studies, tests in a pilot machine and the results of the very early tests of the real system are reviewed

  2. Performance approximation of pick-to-belt orderpicking systems

    NARCIS (Netherlands)

    M.B.M. de Koster (René)

    1994-01-01

    textabstractIn this paper, an approximation method is discussed for the analysis of pick-to-belt orderpicking systems. The aim of the approximation method is to provide an instrument for obtaining rapid insight in the performance of designs of pick-to-belt orderpicking systems. It can be used to

  3. Ambient Response Analysis of the Great Belt Bridge

    DEFF Research Database (Denmark)

    Brincker, Rune; Frandsen, Jeanette B.; Andersen, Palle

    2000-01-01

    In this paper an ambient response analysis of the Great Belt Bridge is presented. The Great Belt Bridge is one of the largest suspension bridges in the world, and the analysis was carried out in order to investigate the possibilities of estimating reliable damping values from the ambient response...

  4. The Social Construction of the Great Belt Fixed Link

    DEFF Research Database (Denmark)

    Munch, Birgitte

    1994-01-01

    Working paper in Technology Management. Actor Network theory (ANT) used upon the process of negotiating legislation and constructing the Great Belt fixed link.......Working paper in Technology Management. Actor Network theory (ANT) used upon the process of negotiating legislation and constructing the Great Belt fixed link....

  5. Belt conveyor dynamics in transient operation for speed control

    NARCIS (Netherlands)

    He, D.; Pang, Y.; Lodewijks, G.

    2016-01-01

    Belt conveyors play an important role in continuous dry bulk material transport, especially at the mining industry. Speed control is expected to reduce the energy consumption of belt conveyors. Transient operation is the operation of increasing or decreasing conveyor speed for speed control.

  6. Using ASD data to identify the altered minerals for exploring of gold deposit in the Beishan area, North China

    Science.gov (United States)

    Ren, G. L.; Yi, H.; Yang, M.; Liang, N.; Li, J. Q.; Yang, J. L.

    2016-11-01

    Hyperspectral information of altered minerals plays an important role in the identifications of mineralized zones. In this study, the altered minerals of two gold deposits from Fangshankou-Laojinchang regions of Beishan metallogenic belt were measured by ASD field Spectrometer. Many gold deposits would have a close relationship with Variscan magma intrusion, which have been found in study region. The alteration minerals have been divided six types by the spectral results, i.e. sericite, limonite, dolomite, chlorite, epidote and calcite. The distribution characteristics and formations of altered minerals were discussed here. By the ASD, the spectral curve of different geological units in the Jintanzi and Fangshankou gold deposits were analysed and summarized. The results show that the sericite and limonite are mainly related with the gold mineralization and widely occurred in the gold deposits. Therefore, we proposed that the sericite and limonite are the iconic alteration mineral assemblages for gold mineralization and the models of altered minerals for gold deposits could be established in this region.

  7. Optimal control of operation efficiency of belt conveyor systems

    International Nuclear Information System (INIS)

    Zhang, Shirong; Xia, Xiaohua

    2010-01-01

    The improvement of the energy efficiency of belt conveyor systems can be achieved at equipment or operation levels. Switching control and variable speed control are proposed in literature to improve energy efficiency of belt conveyors. The current implementations mostly focus on lower level control loops or an individual belt conveyor without operational considerations at the system level. In this paper, an optimal switching control and a variable speed drive (VSD) based optimal control are proposed to improve the energy efficiency of belt conveyor systems at the operational level, where time-of-use (TOU) tariff, ramp rate of belt speed and other system constraints are considered. A coal conveying system in a coal-fired power plant is taken as a case study, where great saving of energy cost is achieved by the two optimal control strategies. Moreover, considerable energy saving resulting from VSD based optimal control is also proved by the case study.

  8. Optimal control of operation efficiency of belt conveyor systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shirong [Department of Automation, Wuhan University, Wuhan 430072 (China); Xia, Xiaohua [Department of Electrical, Electronic and Computer Engineering, University of Pretoria, Pretoria 0002 (South Africa)

    2010-06-15

    The improvement of the energy efficiency of belt conveyor systems can be achieved at equipment or operation levels. Switching control and variable speed control are proposed in literature to improve energy efficiency of belt conveyors. The current implementations mostly focus on lower level control loops or an individual belt conveyor without operational considerations at the system level. In this paper, an optimal switching control and a variable speed drive (VSD) based optimal control are proposed to improve the energy efficiency of belt conveyor systems at the operational level, where time-of-use (TOU) tariff, ramp rate of belt speed and other system constraints are considered. A coal conveying system in a coal-fired power plant is taken as a case study, where great saving of energy cost is achieved by the two optimal control strategies. Moreover, considerable energy saving resulting from VSD based optimal control is also proved by the case study. (author)

  9. Energetic electrons in the inner belt in 1968

    Energy Technology Data Exchange (ETDEWEB)

    West, Jr, H I; Buck, R M [California Univ., Livermore (USA). Lawrence Livermore Lab.

    1976-07-01

    Pitch-angle data were obtained by the Lawrence Livermore Laboratory's scanning, magnetic electron spectrometer on OGO 5 during its traversals of the inner belt in 1968. Data from the five lowest-energy channels 79 to 822 keV, were analyzed. The inner-belt electron injection following two storm periods was observed; the first was the mild storm of 11 June and the second the more intense storms of 31 October and 1 November. Comparisons with other data indicate that only a small Starfish residual (at > 1 MeV) still remained in the heart of the inner belt; hence, the results are indicative of the normal inner belt. The data are discussed in terms of current ideas regarding the source and loss of particles in the inner belt.

  10. Wearing an abdominal belt increases diastolic blood pressure.

    Science.gov (United States)

    Rafacz, W; McGill, S M

    1996-09-01

    The purpose of this study was to determine the effect of wearing an abdominal belt on blood pressure (systolic and diastolic) and heart rate during a variety of tasks. The belt was typical of the elastic type with suspenders and Velcro tabs for cinching the belt snug. The tasks performed included sitting at rest, sitting with the torso inclined forward at 45 degrees, standing with the torso inclined forward at 45 degrees (with and without holding an 11-kg weight), a trunk axial rotation task, and squat lifting. Blood pressure was monitored noninvasively with a FINAPRES blood pressure monitor. Twenty healthy men performed each task with and without the abdominal belt. Although no significant increases in mean systolic blood pressure or heart rate were found, there was a significant increase in diastolic blood pressure in all conditions. All people considering wearing an abdominal belt should also consider the risks and liability associated with the additional cardiovascular load, particularly heart attack and stroke.

  11. Transfer points of belt conveyors operating with unfavorable bulk

    Energy Technology Data Exchange (ETDEWEB)

    Goehring, H [Technische Universitaet, Dresden (German Democratic Republic)

    1989-06-01

    Describes design of belt conveyor chutes that transfer bulk of surface mines from one conveyor to another. Conveyor belt velocity is a significant parameter. Unfavorable chute design may lead to bulk flow congestion, bulk velocity losses etc. The bulk flow process is analyzed, bulk flow velocities, belt inclinations and bulk feeding from 2 conveyors into one chute are taken into account. Conventional chutes have parabolic belt impact walls. An improved version with divided impact walls is proposed that maintains a relatively high bulk velocity, reduces friction at chute walls and decreases wear and dirt build-up. Design of the improved chute is explained. It is built to adapt to existing structures without major modifications. The angle between 2 belt conveyors can be up to 90 degrees, the best bulk transfer is noted at conveyor angles below 60 degrees. Various graphs and schemes are provided. 6 refs.

  12. Equilibria and Free Vibration of a Two-Pulley Belt-Driven System with Belt Bending Stiffness

    Directory of Open Access Journals (Sweden)

    Jieyu Ding

    2014-01-01

    Full Text Available Nonlinear equilibrium curvatures and free vibration characteristics of a two-pulley belt-driven system with belt bending stiffness and a one-way clutch are investigated. With nonlinear dynamical tension, the transverse vibrations of the translating belt spans and the rotation motions of the pulleys and the accessory shaft are coupled. Therefore, nonlinear piecewise discrete-continuous governing equations are established. Considering the bending stiffness of the translating belt spans, the belt spans are modeled as axially moving beams. The pattern of equilibria is a nontrivial solution. Furthermore, the nontrivial equilibriums of the dynamical system are numerically determined by using two different approaches. The governing equations of the vibration near the equilibrium solutions are derived by introducing a coordinate transform. The natural frequencies of the dynamical systems are studied by using the Galerkin method with various truncations and the differential and integral quadrature methods. Moreover, the convergence of the Galerkin truncation is investigated. Numerical results reveal that the study needs 16 terms after truncation in order to determine the free vibration characteristics of the pulley-belt system with the belt bending stiffness. Furthermore, the first five natural frequencies are very sensitive to the bending stiffness of the translating belt.

  13. The Metamorphic Rocks-Hosted Gold Mineralization At Rumbia Mountains Prospect Area In The Southeastern Arm of Sulawesi Island, Indonesia

    Directory of Open Access Journals (Sweden)

    Hasria Hasria

    2017-09-01

    Full Text Available Recently, in Indonesia gold exploration activities  are not only focused along volcanic-magmatic belts, but also starting to shift along metamorphic and sedimentary terrains. The study area is located in Rumbia mountains, Bombana Regency, Southeast Sulawesi Province. This paper is aimed to describe characteristics of alteration and ore mineralization associated  with metamorphic rock-related gold deposits.  The study area is found the placer and  primary gold hosted by metamorphic rocks. The gold is evidently derived from gold-bearing quartz veins hosted by Pompangeo Metamorphic Complex (PMC. These quartz veins are currently recognized in metamorphic rocks at Rumbia Mountains. The quartz veins are mostly sheared/deformed, brecciated, irregular vein, segmented and  relatively massive and crystalline texture with thickness from 1 cm to 15.7 cm. The wallrock are generally weakly altered. Hydrothermal alteration types include sericitization, argillic, inner propylitic, propylitic, carbonization and carbonatization. There some precious metal identified consist of native gold and ore mineralization including pyrite (FeS2, chalcopyrite (CuFeS2, hematite (Fe2O3, cinnabar (HgS, stibnite (Sb2S3 and goethite (FeHO2. The veins contain erratic gold in various grades from below detection limit <0.0002 ppm to 18.4 ppm. Based on those characteristics, it obviously indicates that the primary gold deposit present in the study area is of orogenic gold deposit type. The orogenic gold deposit is one of the new targets for exploration in Indonesia

  14. Non-linear belt transient analysis. A hybrid model for numerical belt conveyor simulation

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, A. [Scientific Solutions, Inc., Aurora, CO (United States)

    2008-07-01

    Frictional and rolling losses along a running conveyor are discussed due to their important influence on wave propagation during starting and stopping. Hybrid friction models allow belt rubber losses and material flexing to be included in the initial tension calculations prior to any dynamic analysis. Once running tensions are defined, a numerical integration method using non-linear stiffness gradients is used to generate transient forces during starting and stopping. A modified Euler integration technique is used to simulate the entire starting and stopping cycle in less than 0.1 seconds. The procedure enables a faster scrutiny of unforeseen conveyor design issues such as low belt tension zones and high forces at drives. (orig.)

  15. Stealing the Gold

    International Nuclear Information System (INIS)

    Whittington, S G

    2005-01-01

    Stealing the Gold presents a survey of some of the most exciting topics in condensed matter physics today, from the perspective of the pioneering work of Sam Edwards. Original articles from leaders in the field, including several Nobel laureates, highlight the historical development as well as new and emerging areas. This book would be of interest to graduate students and researchers in condensed matter physics, statistical physics and theoretical physics. Over the course of nearly half a century, Sam Edwards has led the field of condensed matter physics in new directions, ranging from the electronic and statistical properties of disordered materials to the mechanical properties of granular materials. Along the way he has provided seminal contributions to fluid mechanics, polymer science, surface science and statistical mechanics. This volume celebrates the immense scope of his influence by presenting a collection of original articles by recognized leaders in theoretical physics, including two Nobel laureates and a Fields medalist, which describe the genesis, evolution and future prospects of the various sub-fields of condensed matter theory, along with reprints of a selection of Edwards' seminal papers that helped give birth to the subject. Stealing the Gold, Edwards' favourite caricature of the relationship between theoretical physicists and nature, will be of singular interest to graduate students looking for an overview of some of the most exciting areas of theoretical physics, as well as to researchers in condensed matter physics looking for a comprehensive, broad and uniquely incisive snapshot of their subject at the dawn of the 21st century. (book review)

  16. Alteration and petrology of Intrusive Rocks associated with Gold Mineralization at Kuh-E-Zar Gold Deposit, Torbat-e-Heydaryeh

    Directory of Open Access Journals (Sweden)

    Alireza Mazloumi Bajestani

    2009-09-01

    Full Text Available Kuh- e -Zar gold deposit located 35 km west of Torbat-e-Heydaryeh, (Khorassan e- Razavi province, East of Iran. This deposit is a specularite-rich Iron oxide type (IOCG. This mine is situated within Khaf-Bardascan volcanic plutonic belt. Based on recent exploration along this belt, several IOCG type system plus Kuh-e-Zar deposit are discovered. In the study area, several type of tuff and lava having acid to intermediate composition are identified (upper Eocene. Oligo-Miocene granite, granodiorite, synogranite and monzonite intruded upper Eocene andesite-dacite-rhyolite. Intrusive rocks are meta-aluminous, medium to high-K series I-type. Based on spider diagram, intrusive rocks show enrichment in LILE = K, Th, Rb and depletion in HFSE = Nb, Sr, Ti. Based geochemistry of igneous rock, they formed in continental margin subduction zone. Propylitic (chlorite alteration is dominated and covers large area. Silicification is restricted only to mineralized zones. Argillic and albitization is found in certain location and cover small areas. The style of mineralization was controlled by the type and geometry of fault zones. Mineralization is found as vein, stockwork and breccias. Hypogene mineral Paragenesis include: specularite-quartz-gold-chlorite ± chalcopyrite ± pyrite ± galena ± barite. Secondary minerals formed due to oxidation are: goethite, limonite, lepidocrucite, Malachite, Azurite, Covelite, Cerucite, hydrocerucite, Pyrolusite and Smitsonite. In a few localities, chalcopyrite and minor pyrite and galena are found. Based on SEM analysis gold is present as electrum. Mineralization appeared in different type such as vein, stockwork and Hydrothermal breccia in strike sleep fault zone which are hidden inside volcano plutonic rocks. The average gold grade is between 3.02 ppm and ore reserve is estimated more than 3 million tons (cut off grade = 0.7 ppm.

  17. The Foundations of Radiation Belt Research

    Science.gov (United States)

    Ludwig, G. H.

    2008-12-01

    phenomenon. It also provided the first hint that there were two distinct radiation belts, although that conclusion was not reached until later. Although that new information was quickly announced, the results of the high altitude nuclear detonations were kept secret until well into 1959. They clearly revealed the charged particle shells created by the Argos nuclear detonations. The next major step in mapping and understanding the high-intensity radiation involved the launch of deep space probes Pioneers III and IV in December 1958 and March 1959. Although both launches fell short in their primary objective, to reach the moon, they traveled far enough from the Earth to fully meet the needs of the scientific experiment. They very clearly showed the two-radiation belt structure, and mapped its extent. They also showed the probable effect of a magnetic storm on 25 February, thus indicating the direct influence of solar activity on the outer belt. By the end of 1959, the existence of the Van Allen Radiation Belts and their general structure were solidly established, early information about the composition of the radiation was appearing in print, and energetic work was under way to understand the physics of the processes involved.

  18. Space electronics: radiation belts set new challenges

    International Nuclear Information System (INIS)

    Leray, J.L.; Barillot, C.; Boudenot, J.C.

    1999-01-01

    Telecommunications satellites have been in use since 1962 with the first satellite network (constellation) coming into operation in 1966. GPS systems have been available since the mid seventies. Until now, all these systems have avoided orbits which lie within the radiation belts. The latest constellation projects, offering much wider bandwidths, need to use orbits between 1500 and 2000 km, where the proton density is at its highest. The vulnerability of future generations of components can be predicted by extrapolating the behaviour of current devices. Screening is not a viable option due to cost and weight limitations in satellite applications. As a result, satellite and component manufacturers are seeking new methods of hardening components or making them more radiation tolerant in an environment where the radiation levels are ten times those currently experiences. (authors)

  19. Torque-transmitting mechanism of a metal CVT belt; Kinzoku CVT belt no torque dentatsu mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, D; Mabuchi, Y; Kato, Y [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    The slip mechanism of a metal CVT belt which consisted of several hundred V-shaped elements and two sets of laminated metal rings was analyzed by focusing on the distribution of the gaps occurring between the elements, and a simulation which could predict the slip-limit torque at which the slip ratio increases sharply was developed. In this paper, the outline of the simulation is shown with some comparison between the calculated results and the experimental data. 3 refs., 13 figs.

  20. Inclination Mixing in the Classical Kuiper Belt

    Science.gov (United States)

    Volk, Kathryn; Malhotra, Renu

    2011-07-01

    We investigate the long-term evolution of the inclinations of the known classical and resonant Kuiper Belt objects (KBOs). This is partially motivated by the observed bimodal inclination distribution and by the putative physical differences between the low- and high-inclination populations. We find that some classical KBOs undergo large changes in inclination over gigayear timescales, which means that a current member of the low-inclination population may have been in the high-inclination population in the past, and vice versa. The dynamical mechanisms responsible for the time variability of inclinations are predominantly distant encounters with Neptune and chaotic diffusion near the boundaries of mean motion resonances. We reassess the correlations between inclination and physical properties including inclination time variability. We find that the size-inclination and color-inclination correlations are less statistically significant than previously reported (mostly due to the increased size of the data set since previous works with some contribution from inclination variability). The time variability of inclinations does not change the previous finding that binary classical KBOs have lower inclinations than non-binary objects. Our study of resonant objects in the classical Kuiper Belt region includes objects in the 3:2, 7:4, 2:1, and eight higher-order mean motion resonances. We find that these objects (some of which were previously classified as non-resonant) undergo larger changes in inclination compared to the non-resonant population, indicating that their current inclinations are not generally representative of their original inclinations. They are also less stable on gigayear timescales.

  1. Directed Assembly of Gold Nanoparticles

    DEFF Research Database (Denmark)

    Westerlund, Axel Rune Fredrik; Bjørnholm, Thomas

    2009-01-01

    As a complement to common "top-down" lithography techniques, "bottom-up" assembly techniques are emerging as promising tools to build nanoscale structures in a predictable way. Gold nanoparticles that are stable and relatively easy to synthesize are important building blocks in many such structures...... due to their useful optical and electronic properties. Programmed assembly of gold nanoparticles in one, two, and three dimensions is therefore of large interest. This review focuses on the progress from the last three years in the field of directed gold nanoparticle and nanorod assembly using...

  2. GOLD and the fixed ratio

    Directory of Open Access Journals (Sweden)

    Vestbo J

    2012-09-01

    Full Text Available Jørgen VestboUniversity of Manchester, Manchester, UKI read with interest the paper entitled "Diagnosis of airway obstruction in the elderly: contribution of the SARA study" by Sorino et al in a recent issue of this journal.1 Being involved in the Global Initiative for Obstructive Lung Diseases (GOLD, it is nice to see the interest sparked by the GOLD strategy document. However, in the paper by Sorino et al, there are a few misunderstandings around GOLD and the fixed ratio (forced expiratory volume in 1 second/forced volume vital capacity < 0.70 that need clarification.View original paper by Sorino and colleagues.

  3. Space Weather Effects in the Earth's Radiation Belts

    Science.gov (United States)

    Baker, D. N.; Erickson, P. J.; Fennell, J. F.; Foster, J. C.; Jaynes, A. N.; Verronen, P. T.

    2018-02-01

    The first major scientific discovery of the Space Age was that the Earth is enshrouded in toroids, or belts, of very high-energy magnetically trapped charged particles. Early observations of the radiation environment clearly indicated that the Van Allen belts could be delineated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been subsequently explored by several space missions. Recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed many novel properties of the radiation belts, especially for electrons at highly relativistic and ultra-relativistic kinetic energies. In this review we summarize the space weather impacts of the radiation belts. We demonstrate that many remarkable features of energetic particle changes are driven by strong solar and solar wind forcings. Recent comprehensive data show broadly and in many ways how high energy particles are accelerated, transported, and lost in the magnetosphere due to interplanetary shock wave interactions, coronal mass ejection impacts, and high-speed solar wind streams. We also discuss how radiation belt particles are intimately tied to other parts of the geospace system through atmosphere, ionosphere, and plasmasphere coupling. The new data have in many ways rewritten the textbooks about the radiation belts as a key space weather threat to human technological systems.

  4. Modeling of Jupiter's electron an ion radiation belts

    International Nuclear Information System (INIS)

    Sicard, Angelica

    2004-01-01

    In the Fifties, James Van Allen showed the existence of regions of the terrestrial magnetosphere consisted of energetic particles, trapped by the magnetic field: the radiation belts. The radiation belts of the Earth were the subject of many modeling works and are studied since several years at the Departement Environnement Spatial (DESP) of ONERA. In 1998, the DESP decided to adapt the radiation belts model of the Earth, Salammbo, to radiation environment of Jupiter. A first thesis was thus carried out on the subject and a first radiation belts model of electrons of Jupiter was developed [Santos-Costa, 2001]. The aim of this second thesis is to develop a radiation belts model for protons and heavy ions. In order to validate the developed model, the comparisons between Salammbo results and observations are essential. However, the validation is difficult in the case of protons and heavy ions because in-situ measurements of the probes are very few and most of the time contaminated by very energetic electrons. To solve this problem, a very good model of electrons radiation belts is essential to confirm or cancel the contamination of protons and heavy ions measurements. Thus, in parallel to the development of the protons and heavy ions radiation belts model, the electrons models, already existing, has been improved. Then Salammbo results have been compared to the different observations available (in-situ measurements, radio-astronomical observations). The different comparisons show a very good agreement between Salammbo results and observations. (author) [fr

  5. Speed Controlled Belt Conveyors: Drives and Mechanical Considerations

    Directory of Open Access Journals (Sweden)

    BEBIC, M. Z.

    2018-02-01

    Full Text Available The paper presents variable speed belt conveyor system where the reference speed is changed in order to achieve improved energy efficiency of operation. The recorded measurements show that belt tension varies within the same limits as under constant speed operation. These results introduce a new insight of the present state of the art in variable speed belt conveyor drives. The system is realized with remote control from the control center on an open pit mine. The structure of the multi-motor drive system of a single conveyor, as well as of the network-based control system distributed among belt conveyor stations and the control center are shown. Speed control of a belt conveyor system is organized to provide better utilization of the available material cross section on the belt and reduced electrical energy consumption of the drive. The experimental results obtained on the system prove that, under existing constraints, the applied algorithm has not introduced additional stress to the belt or mechanical assemblies during acceleration and deceleration processes, while providing higher energy efficiency of operation.

  6. Timing belt in power transmission and conveying system

    Directory of Open Access Journals (Sweden)

    Domek Grzegorz

    2018-01-01

    Full Text Available This paper presents the problem of phenomena occurring at the contact of a timing belt and a pulley. Depending on a belt size range these phenomena differ significantly. There is no indication as to what solutions are optimal for drive belts. The analysis of the coupling process and performance tests have shown that the drive belt should have a cord of very good mechanical properties and its raceway side should be made from the material of a low friction coefficient against the pulley material. A flat belt in power transmission and conveying systems cooperates with several elements consisting of timing pulleys, tensioners or guiding rails. In gear with timing belts they depend strongly on characteristics of the process as well as the type of friction. In recent constructions, producers of timing belts are very much concerned about achieving as much slippery surface as possible. The work describes the problem of friction on different surfaces as well as its influence on gear lifetime. Research results confirm that on many surfaces bigger coefficient of friction is expected.

  7. Enhancement of gold recovery using bioleaching from gold concentrate

    Science.gov (United States)

    Choi, S. H.; Cho, K. H.; Kim, B. J.; Choi, N. C.; Park, C. Y.

    2012-04-01

    The gold in refractory ores is encapsulated as fine particles (sometimes at a molecular level) in the crystal structure of the sulfide (typically pyrite with or without arsenopyrite) matrix. This makes it impossible to extract a significant amount of refractory gold by cyanidation since the cyanide solution cannot penetrate the pyrite/arsenopyrite crystals and dissolve gold particles, even after fine grinding. To effectively extract gold from these ores, an oxidative pretreatment is necessary to break down the sulfide matrix. The most popular methods of pretreatment include nitric acid oxidation, roasting, pressure oxidation and biological oxidation by microorganisms. This study investigated the bioleaching efficiency of Au concentrate under batch experimental conditions (adaptation cycles and chemical composition adaptation) using the indigenous acidophilic bacteria collected from gold mine leachate in Sunsin gold mine, Korea. We conducted the batch experiments at two different chemical composition (CuSO4 and ZnSO4), two different adaptation cycles 1'st (3 weeks) and 2'nd (6 weeks). The results showed that the pH in the bacteria inoculating sample decreased than initial condition and Eh increased. In the chemical composition adaptation case, the leached accumulation content of Fe and Pb was exhibited in CuSO4 adaptation bacteria sample more than in ZnSO4 adaptation bacteria samples, possibly due to pre-adaptation effect on chalcopyrite (CuFeS2) in gold concentrate. And after 21 days on the CuSO4 adaptation cycles case, content of Fe and Pb was appeared at 1'st adaptation bacteria sample(Fe - 1.82 and Pb - 25.81 times per control sample) lower than at 2'nd adaptation bacteria sample(Fe - 2.87 and Pb - 62.05 times per control sample). This study indicates that adaptation chemical composition and adaptation cycles can play an important role in bioleaching of gold concentrate in eco-/economic metallurgy process.

  8. An Effective Belt Conveyor for Underground Ore Transportation Systems

    Science.gov (United States)

    Krol, Robert; Kawalec, Witold; Gladysiewicz, Lech

    2017-12-01

    Raw material transportation generates a substantial share of costs in the mining industry. Mining companies are therefore determined to improve the effectiveness of their transportation system, focusing on solutions that increase both its energy efficiency and reliability while keeping maintenance costs low. In the underground copper ore operations in Poland’s KGHM mines vast and complex belt conveyor systems have been used for horizontal haulage of the run-of-mine ore from mining departments to shafts. Basing upon a long-time experience in the field of analysing, testing, designing and computing of belt conveyor equipment with regard to specific operational conditions, the improvements to the standard design of an underground belt conveyor for ore transportation have been proposed. As the key elements of a belt conveyor, the energy-efficient conveyor belt and optimised carrying idlers have been developed for the new generation of underground conveyors. The proposed solutions were tested individually on the specially constructed test stands in the laboratory and in the experimental belt conveyor that was built up with the use of prototype parts and commissioned for the regular ore haulage in a mining department in the KGHM underground mine “Lubin”. Its work was monitored and the recorded operational parameters (loadings, stresses and strains, energy dissipation, belt tracking) were compared with those previously collected on a reference (standard) conveyor. These in-situ measurements have proved that the proposed solutions will return with significant energy savings and lower maintenance costs. Calculations made on the basis of measurement results in the specialized belt conveyor designing software allow to estimate the possible savings if the modernized conveyors supersede the standard ones in a large belt conveying system.

  9. Genesis and gold (Copper) Potential in Darestan-Baghu mining area (South of Damghan)

    International Nuclear Information System (INIS)

    Tajeddin, H. A.; Rashid Nezhad Omran, N.; Babakhani, A. R.

    2000-01-01

    Darestan-Baghu gold mining area is exposed at about 100 km south of Damghan. The area is a part of Torud-Chahshirin volcano-plutonic belt that crops out as a ho rst with a N E-S W trend in the northern limit Dasht-e-Kavir. The outcrops in the area are Middle-Eocene volcano-pyroclastics with andesite to da cite in composition, which are intruded by a number of intrusive s including granite to granodiorite bodies. Mineralization in Darestan gold occurrence consists of a copper (gold)-bearing silicic vein with 400 meter length occurring within a N-S trending normal fault in andesitic to dacitic- andesitic massive breccia tuff associated with silicic, argillic and propylitic alterations. Mineralization in the vein includes quartz, chalcopyrite, pyrite, gold, specularite, malachite, and iron-hydroxides. Gold mineralization in Baghu vein (at about 3 km N E of Darestan gold occurrence) is as a silicic vein with 700 meter length occurring within a granodiorite-granite sub volcanic with argillic alteration. Mineralization in Baghu vein consists of quartz, pyrite, chalcopyrite, gold, iron oxides and iron-hydroxides, malachite, chalcocite, covellite and tourmaline. Field observations indicate that considerable contents of gold in Darestan area mainly related to sulfide-bearing silicic veins are intruded within N-S normal faults that are generally associated with hydrothermal alteration of argillic, silicic and chloritic (± epi dote) zones. investigation on other mineralized zones of Darestan and Baghu areas suggests a clear genetic relationship between Darestan copper (gold) occurrence and gold-bearing silicic vein of Baghu. Field observations and laboratory studies show a close relationship between the copper (gold) mineralization and late-stage silicic solutions induced from sub volcanic intrusive s with acidic to intermediate composition in Darestan and Baghu districts. Some of the most important lines of evidence are spatial relationship between ore-bearing silicic veins

  10. In harmony with gold and uranium

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    A profile is given on Mr Clive Knobbs as managing director of Harmony gold mine. From March 1 1983 he succeeded as deputy chairman of the group's gold and uranium division, and became the Rand Mines representative on the Gold Producers Committee and the Executive Committee of the Chamber of Mines. The article also takes a look at gold and uranium mining in general

  11. 41 CFR 101-45.002 - Gold.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  12. Size fraction assaying of gold bearing rocks (for gold extraction) by ...

    African Journals Online (AJOL)

    A novel method has been developed for processing and extraction of gold from gold bearing rocks for use by small-scale gold miners in Ghana. The methodology involved crushing of gold bearing hard rocks to fine particles to form a composite sample and screening at a range of sizes. Gold distribution in the composite ...

  13. Gold--a controversial sensitizer

    DEFF Research Database (Denmark)

    Bruze, M; Andersen, Klaus Ejner

    1999-01-01

    allergy to gold sodium thiosulfate were published at the beginning of the 1990s, the allergic nature of the reported positive patch test reactions to gold was questioned. The major argument for such questioning was the lack of demonstrable clinical relevance in most positive reactors. A major reason......Until recently, gold allergy was considered to be extremely rare. Gold has been used and worshipped for thousands of years without any obvious complaints of skin problems, either in those participating in mining and other ways of prospecting, or in those wearing jewellery. When studies on contact...... for the questioning may have been confusion in differentiating between contact allergy and allergic contact dermatitis. To arrive at a diagnosis of allergic contact dermatitis, 3 steps have, in principle, to be fulfilled: (i) establishment of contact allergy; (ii) demonstration of present exposure; (iii) assessment...

  14. Gold, currencies and market efficiency

    Science.gov (United States)

    Kristoufek, Ladislav; Vosvrda, Miloslav

    2016-05-01

    Gold and currency markets form a unique pair with specific interactions and dynamics. We focus on the efficiency ranking of gold markets with respect to the currency of purchase. By utilizing the Efficiency Index (EI) based on fractal dimension, approximate entropy and long-term memory on a wide portfolio of 142 gold price series for different currencies, we construct the efficiency ranking based on the extended EI methodology we provide. Rather unexpected results are uncovered as the gold prices in major currencies lay among the least efficient ones whereas very minor currencies are among the most efficient ones. We argue that such counterintuitive results can be partly attributed to a unique period of examination (2011-2014) characteristic by quantitative easing and rather unorthodox monetary policies together with the investigated illegal collusion of major foreign exchange market participants, as well as some other factors discussed in some detail.

  15. Optical trapping of gold aerosols

    DEFF Research Database (Denmark)

    Schmitt, Regina K.; Pedersen, Liselotte Jauffred; Taheri, S. M.

    2015-01-01

    Aerosol trapping has proven challenging and was only recently demonstrated.1 This was accomplished by utilizing an air chamber designed to have a minimum of turbulence and a laser beam with a minimum of aberration. Individual gold nano-particles with diameters between 80 nm and 200 nm were trapped...... in air using a 1064 nm laser. The positions visited by the trapped gold nano-particle were quantified using a quadrant photo diode placed in the back focal plane. The time traces were analyzed and the trapping stiffness characterizing gold aerosol trapping determined and compared to aerosol trapping...... of nanometer sized silica and polystyrene particles. Based on our analysis, we concluded that gold nano-particles trap more strongly in air than similarly sized polystyrene and silica particles. We found that, in a certain power range, the trapping strength of polystyrene particles is linearly decreasing...

  16. Biomass processing over gold catalysts

    CERN Document Server

    Simakova, Olga A; Murzin, Dmitry Yu

    2014-01-01

    The book describes the valorization of biomass-derived compounds over gold catalysts. Since biomass is a rich renewable feedstock for diverse platform molecules, including those currently derived from petroleum, the interest in various transformation routes has become intense. Catalytic conversion of biomass is one of the main approaches to improving the economic viability of biorefineries.  In addition, Gold catalysts were found to have outstanding activity and selectivity in many key reactions. This book collects information about transformations of the most promising and important compounds derived from cellulose, hemicelluloses, and woody biomass extractives. Since gold catalysts possess high stability under oxidative conditions, selective oxidation reactions were discussed more thoroughly than other critical reactions such as partial hydrogenation, acetalization, and isomerization. The influence of reaction conditions, the role of the catalyst, and the advantages and disadvantages of using gold are pre...

  17. Immunological properties of gold nanoparticles

    OpenAIRE

    Dykman, Lev A.; Khlebtsov, Nikolai G.

    2016-01-01

    In the past decade, gold nanoparticles have attracted strong interest from the nanobiotechnological community owing to the significant progress made in robust and easy-to-make synthesis technologies, in surface functionalization, and in promising biomedical applications. These include bioimaging, gene diagnostics, analytical sensing, photothermal treatment of tumors, and targeted delivery of various biomolecular and chemical cargos. For the last-named application, gold nanoparticles should be...

  18. Biosensors based on gold nanostructures

    OpenAIRE

    Vidotti,Marcio; Carvalhal,Rafaela F.; Mendes,Renata K.; Ferreira,Danielle C. M.; Kubota,Lauro T.

    2011-01-01

    The present review discusses the latest advances in biosensor technology achieved by the assembly of biomolecules associated with gold nanoparticles in analytical devices. This review is divided in sections according to the biomolecule employed in the biosensor development: (i) immunocompounds; (ii) DNA/RNA and functional DNA/RNA; and (iii) enzymes and Heme proteins. In order to facilitate the comprehension each section was subdivided according to the transduction mode. Gold nanoparticles bas...

  19. Characterisation of gold from Fiji

    OpenAIRE

    Naden, Jon; Henney, P.J.

    1995-01-01

    This is a study of the variation in chemistry and inclusion mineralogy of bedrock and placer gold from Fiji. It forms part of a large project, undertaking gold characterisation from a wide range of geological environments in Ecuador, Zimbabwe, Malaysia and Fiji. The work was carried out under the Overseas Development AdministratiodBritish Geological Survey Technology Development and Research programme (Project R5549) as part of the British Government’s provision of technical...

  20. Audio-magnetotelluric investigation of sulfide mineralization in Proterozoic-Archean greenstone belts of Eastern Indian Craton

    Science.gov (United States)

    Singh, Shailendra; Maurya, Ved P.; Singh, Roshan K.; Srivastava, Shalivahan; Tripathi, Anurag; Adhikari, P. K.

    2018-04-01

    Greenstone belts are well known for gold occurrences at different regions of the world. The Dhanjori basin in the eastern Singhbhum region shows major characteristics of a rifted greenstone belt. Initially, we conducted 14 audio-magnetotelluric (AMT) measurements for a profile of ˜ 20 km in the frequency range of 1 kHz to 10 Hz over this rather complex geologic environment covering Dhanjori Volcanics (DhV) and Kolhan Group (KG). Subsequently, gravity and magnetic surveys were also conducted over this AMT profile. The purpose of the survey was to identify and map conductive features and to relate them to metallogeny of the area along with the mapping of the basement of Dhanjori basin. The strike analysis showed N30°W strike for DhV for all the frequencies and for sites over KG domain in the frequency range of 100-10 Hz, but for KG domain, the obtained strike in 1 kHz to 100 Hz is N45°E. As the combination of transverse electric (TE), transverse magnetic (TM) and tipper (Tzy) can recover the electrical signature in complex geological environment, we discuss the conductivity model obtained from TE+TM+Tzy only. The inversion was carried for the regional profile with 14 sites and for 7 sites over KG domain. Conductivity model shows two well resolved conductors, one each in KG and Quartz Pebble Conglomerate Dhanjori (QPCD) domains respectively showing common linked concordant features between these regional and KG profiles. The conductors are interpreted as sulfide mineralization linked with QPCD group of rocks which may host gold. These conductors are also horizontally disposed due to the intrusive younger Mayurbhanj Granite. These intrusives correlate well with the gravity modeling as well. The thickness of the Dhanjori basin at the central is about 3.0 km, similar to that from gravity modeling. The conductivity model also indicates the presence of shallow conductors, but could not be resolved due to lack of high frequency data. However, the results from the close

  1. MACRO MODEL OF SEAT BELT USE BY CAR DRIVERS AND PASSENGERS

    Directory of Open Access Journals (Sweden)

    Kazimierz JAMROZ

    2013-12-01

    Full Text Available The article presents some problems of seat belt use by car drivers and passengers. It looks in particular at seat belt use and effectiveness in selected countries. Next, factors of seat belt use are presented and methodology of model development. A macro model of seat belt use is presented based on data from around fifty countries from different continents.

  2. Goldenphilicity: Luminescent gold compounds

    International Nuclear Information System (INIS)

    Sansores, L.E.

    2002-01-01

    In the solids and molecules different types of bonds are presented depending on the involved atoms, covalent bonds are common among elements of open shell, where more bond orbitals are filled than anti bond orbitals. It is expected that ionic bonds among closed shell atoms which have charges of opposite sign. Bonds type Van der Waals are presented among molecules which have a bipolar moment. It would not be expected bonds among zero charge species, or more generally with the same nominal charge and in any case the attractive forces would be very small. In fact it is expected that two metallic cations to be repelled each other. There recently is evidence that in organic or organometallic compounds could exist attractive interactions between two cations of the d 8 -d 10 -s 2 families. These bonds are weak but stronger than those of Van der Waals. They are compared with the hydrogen bonds. In this work it was reviewed some examples in which the goldenphilicity plays an important role in the luminescence that the gold complexes present. Examples of mono, bi and trinuclear and the structures that these organometallic compounds could take are examined. (Author)

  3. Source of boron in the Palokas gold deposit, northern Finland: evidence from boron isotopes and major element composition of tourmaline

    Science.gov (United States)

    Ranta, Jukka-Pekka; Hanski, Eero; Cook, Nick; Lahaye, Yann

    2017-06-01

    The recently discovered Palokas gold deposit is part of the larger Rompas-Rajapalot gold-mineralized system located in the Paleoproterozoic Peräpohja Belt, northern Finland. Tourmaline is an important gangue mineral in the Palokas gold mineralization. It occurs as tourmalinite veins and as tourmaline crystals in sulfide-rich metasomatized gold-bearing rocks. In order to understand the origin of tourmaline in the gold-mineralized rocks, we have investigated the major element chemistry and boron isotope composition of tourmaline from three areas: (1) the Palokas gold mineralization, (2) a pegmatitic tourmaline granite, and (3) the evaporitic Petäjäskoski Formation. Based on textural evidence, tourmaline in gold mineralization is divided into two different types. Type 1 is located within the host rock and is cut by rock-forming anthophyllite crystals. Type 2 occurs in late veins and/or breccia zones consisting of approximately 80% tourmaline and 20% sulfides, commonly adjacent to quartz veins. All the studied tourmaline samples belong to the alkali-group tourmaline and can be classified as dravite and schorl. The δ11B values of the three localities lie in the same range, from 0 to -4‰. Tourmaline from the Au mineralization and from the Petäjäskoski Formation has similar compositional trends. Mg is the major substituent for Al; inferred low Fe3+/Fe2+ ratios and Na values (molybdenite related to the tourmaline-sulfide-quartz veins, we propose that the tourmaline-forming process is a result of a single magmatic-hydrothermal event related to the extensive granite magmatism at around 1.79-1.77 Ga. Tourmaline was crystallized throughout the hydrothermal process, which resulted in the paragenetic variation between type 1 and type 2. The close association of tourmaline and gold suggests that the gold precipitated from the same boron-rich source as tourmaline.

  4. Continuing scearch for a new type charging belt

    International Nuclear Information System (INIS)

    Jones, N.L.

    1995-01-01

    The EN Tandem accelerator at Oak Ridge National Laboratory (ORNL) operates to support a varied program of atomic physics research. As such, the demands on the accelerator often require a range of operation from ∼0.38 to 7.0 MV on the terminal, with low ripple and long term steady state operation. The standard charging belts obtained from the manufacture have generally given acceptable performance, but it is reasonable that modem manufacturing techniques and materials could increase belt lifetimes and improve accelerator performance, particularly voltage ripple. A new belt of significantly different construction from that of the conventional belts was specified, purchased, and installed in 1993. After 2800 hours of use at voltages from 0.38 to 5.8 MV, it was removed from the accelerator in early August 1995

  5. A comparative policy analysis of seat belt laws : final report.

    Science.gov (United States)

    2014-06-24

    This analysis examined data from a variety of sources to estimate the benefit of enhancing Iowas current law to require all : passengers to use seat belts. In addition to assessing Iowans opinions about changing the law, a literature review, a ...

  6. "Abomination"--life as a Bible belt gay.

    Science.gov (United States)

    Barton, Bernadette

    2010-01-01

    Drawing on observation, autoethnography, and audio-taped interviews, this article explores the religious backgrounds and experiences of Bible Belt gays. In the Bible Belt, Christianity is not confined to Sunday worship. Christian crosses, messages, paraphernalia, music, news, and attitudes permeate everyday settings. Consequently, Christian fundamentalist dogma about homosexuality-that homosexuals are bad, diseased, perverse, sinful, other, and inferior-is cumulatively bolstered within a variety of other social institutions and environments in the Bible Belt. Of the 46 lesbians and gay men interviewed for this study (age 18-74 years), most describe living through spirit-crushing experiences of isolation, abuse, and self-loathing. This article argues that the geographic region of the Bible Belt intersects with religious-based homophobia. Informants explained that negative social attitudes about homosexuality caused a range of harmful consequences in their lives including the fear of going to hell, depression, low self-esteem, and feelings of worthlessness.

  7. Channel belt architecture formed by a meandering river

    NARCIS (Netherlands)

    Lageweg, W.I. van de; Dijk, W.M. van; Kleinhans, M.G.

    2013-01-01

    Stratification in channel belts is the key to reconstructing formative channel dimensions and palaeoflow conditions; this requires an understanding of the relation between river morphodynamics and set thickness. So far, theories for reconstruction of the original morphology from preserved

  8. Gan-Hang tectonic belt and its geologic significance

    International Nuclear Information System (INIS)

    Deng Jiarui; Zhang Zhiping.

    1989-01-01

    Gan-Hang tectonic belt is predominantly controlled by Gan-Hang fracture zone. It is mainly composed of Yongfeng-Zhuji downwarping zone, Gan-Hang volcanic activity structural belt and Gan-Hang red basin downfaulted zone. Gan-Hang fracture zone is derived from evolution and development of Shaoxing-Jiangshan deep fracture. It is mainly composed of three deep and large fracture and Fuzhou-Yongfeng large fracture. The fracture zone is a long active belt, but in each active period the geologic structural patterns intensity, depth and forming time were not same. Gan-Hang tectonic belt possesses obvious inheritance. It has always maintained the character of the relative depression or low land since the Caledonian movement. This specific structural environment is favourable for uranium mineralization. At any rate, the formation of this uranium minerogenetic zone has been experiencing a long and complicated processes which were closely associated with long activity of Gan-Hang fracture zone

  9. REDDY MAIN BELT ASTEROID SPECTRA V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains low-resolution (R~150) near-infrared (0.7-2.5 microns) spectra of 90 main belt asteroids observed with the SpeX instrument on the NASA...

  10. Magmatic formations in the Okhotsk--Chukotka volcanogenic belt

    Energy Technology Data Exchange (ETDEWEB)

    Osipov, A.P.

    1976-05-01

    The relationship between the Okhotsk-Chukotka volcanogenic belt of Northeast USSR and the stage of evolution of magnetism and tectonic development of the region are examined. Recognizing the associations of effusive and intrusive rocks that are typical of the southern part of the volcanogenic belt and that are joined together by some characteristic features, a basic plan is presented for examination of the problem of magnetic formations. On the basis of the distinctive characteristics of epigeosynclinal tectonic development of the territory and the sequence of formation of the magmatic rocks within it, three main groups: volcanic, coleanoplutonic, and plutonic, can be distinguished; and a general scheme of development of these types in space and time within the volcanogenic belt can be developed. According to this scheme, four main stages can be recognized in the Mesozoic and Cenozoic magmatic evolution of the Okhotsk-Chukotka belt. This scheme of classification takes into consideration the factor of the structural development of this tectonomagmatic element.

  11. Second longest conveyor belt in UK installed and fully operational

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-01

    A conveyor belt (which after the completion of the Selby complex will be the second longest conveyor belt in the UK) has been installed at the Prince Charles Drift Mine, Prince of Wales Colliery, United Kingdom. The 1706 m conveyor is the sole underground-to-surface conveyor at the Drift Mine, and is powered by a single 2240 kW, 3000 hp drive unit.

  12. Exploring the collisional evolution of the asteroid belt

    Science.gov (United States)

    Bottke, W.; Broz, M.; O'Brien, D.; Campo Bagatin, A.; Morbidelli, A.

    2014-07-01

    The asteroid belt is a remnant of planet-formation processes. By modeling its collisional and dynamical history, and linking the results to constraints, we can probe how the planets and small bodies formed and evolved. Some key model constraints are: (i) The wavy shape of the main-belt size distribution (SFD), with inflection points near 100-km, 10--20-km, 1 to a few km, and ˜0.1-km diameter; (ii) The number of asteroid families created by the catastrophic breakup of large asteroid bodies over the last ˜ 4 Gy, with the number of disrupted D > 100 km bodies as small as ˜20 or as large as 60; (iii) the flux of small asteroids derived from the main belt that have struck the Moon over the last 3.5 Ga --- crater SFDs on lunar terrains with known ages suggest the D 100 km bodies have been significantly battered, but only a fraction have been catastrophically disrupted. Conversely, most small asteroids today are byproducts of fragmentation events. These results are consistent with growing evidence that most of the prominent meteorite classes were produced by young asteroid families. The big question is how to use what we know to determine the main belt's original size and state. This work is ongoing, but dynamical models hint at many possibilities, including both the late arrival and late removal of material from the main belt. In addition, no model has yet properly accounted for the bombardment of the primordial main belt by leftover planetesimals in the terrestrial planet region. It is also possible to use additional constraints, such as the apparent paucity of Vesta-like or V-type objects in the outer main belt, to argue that the primordial main belt at best only 3--4 its current mass at its start. In our talk, we will review what is known, what has been predicted, and some intriguing directions for the future.

  13. SPECIFIC RESISTANCE AND SPECIFIC INTENSITY OF BELT SANDING OF WOOD

    Directory of Open Access Journals (Sweden)

    Boleslaw Porankiewicz

    2010-06-01

    Full Text Available This paper examines and discusses the specific belt sanding resistance K (N·cm-2 and specific belt sanding intensity SI (g·cm-2·min-1, for wood of Pinus sylvestris L., Picea abies L., Quercus robra L., Acer pseudoplatanus L., Alnus glutinosa Gaertn., and Populus Nigra L., by different sanding pressure pS, different sanding grit NG number, and different wood grain angles Phi(v.

  14. Formation and Decay of the Inner Electron Radiation Belt

    Science.gov (United States)

    2017-01-09

    a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 09-01-2017 2. REPORT TYPE...radiation belt: CRAND and trapped solar protons......17 APPENDIX C - Inward diffusion and loss of radiation belt protons...transfer orbit that can be damaged by the intense charged -particle environment. Protons are the prominent hazard, often causing single event upsets in

  15. An Empirical Planetesimal Belt Radius–Stellar Luminosity Relation

    Science.gov (United States)

    Matrà, L.; Marino, S.; Kennedy, G. M.; Wyatt, M. C.; Öberg, K. I.; Wilner, D. J.

    2018-05-01

    Resolved observations of millimeter-sized dust, tracing larger planetesimals, have pinpointed the location of 26 Edgeworth–Kuiper Belt analogs. We report that a belt’s distance R to its host star correlates with the star’s luminosity L ⋆, following R\\propto {L}\\star 0.19 with a low intrinsic scatter of ∼17%. Remarkably, our Edgeworth–Kuiper Belt in the solar system and the two CO snow lines imaged in protoplanetary disks lie close to this R–L ⋆ relation, suggestive of an intrinsic relationship between protoplanetary disk structures and belt locations. To test the effect of bias on the relation, we use a Monte Carlo approach and simulate uncorrelated model populations of belts. We find that observational bias could produce the slope and intercept of the R–L ⋆ relation but is unable to reproduce its low scatter. We then repeat the simulation taking into account the collisional evolution of belts, following the steady-state model that fits the belt population as observed through infrared excesses. This significantly improves the fit by lowering the scatter of the simulated R–L ⋆ relation; however, this scatter remains only marginally consistent with the one observed. The inability of observational bias and collisional evolution alone to reproduce the tight relationship between belt radius and stellar luminosity could indicate that planetesimal belts form at preferential locations within protoplanetary disks. The similar trend for CO snow line locations would then indicate that the formation of planetesimals or planets in the outer regions of planetary systems is linked to the volatility of their building blocks, as postulated by planet formation models.

  16. Design of belt conveyors in bulk terminal applications. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, P J; Ramos, C M

    1985-10-01

    This paper discusses belt conveyors and their development in bulk terminal applications in South Africa. Single- and multi-product terminal philosophy is discussed, including methods of handling different products over the same system and limiting the effects of degradation at transfer points. In Part II, some aspects of belt conveyor design, as well as the results of tests on a chute designed to handle a range of products, will be covered. 23 references.

  17. Dark nebulae, dark lanes, and dust belts

    CERN Document Server

    Cooke, Antony

    2012-01-01

    As probably the only book of its type, this work is aimed at the observer who wants to spend time with something less conventional than the usual fare. Because we usually see objects in space by means of illumination of one kind or another, it has become routine to see them only in these terms. However, part of almost everything that we see is the defining dimension of dark shading, or even the complete obscuration of entire regions in space. Thus this book is focused on everything dark in space: those dark voids in the stellar fabric that mystified astronomers of old; the dark lanes reported in many star clusters; the magical dust belts or dusty regions that have given so many galaxies their identities; the great swirling 'folds' that we associate with bright nebulae; the small dark feature detectable even in some planetary nebulae; and more. Many observers pay scant attention to dark objects and details. Perhaps they are insufficiently aware of them or of the viewing potential they hold, but also it may be...

  18. Dynamical Classifications of the Kuiper Belt

    Science.gov (United States)

    Maggard, Steven; Ragozzine, Darin

    2018-04-01

    The Minor Planet Center (MPC) contains a plethora of observational data on thousands of Kuiper Belt Objects (KBOs). Understanding their orbital properties refines our understanding of the formation of the solar system. My analysis pipeline, BUNSHIN, uses Bayesian methods to take the MPC observations and generate 30 statistically weighted orbital clones for each KBO that are propagated backwards along their orbits until the beginning of the solar system. These orbital integrations are saved as REBOUND SimulationArchive files (Rein & Tamayo 2017) which we will make publicly available, allowing many others to perform statistically-robust dynamical classification or complex dynamical investigations of outer solar system small bodies.This database has been used to expand the known collisional family members of the dwarf planet Haumea. Detailed orbital integrations are required to determine the dynamical distances between family members, in the form of "Delta v" as measured from conserved proper orbital elements (Ragozzine & Brown 2007). Our preliminary results have already ~tripled the number of known Haumea family members, allowing us to show that the Haumea family can be identified purely through dynamical clustering.We will discuss the methods associated with BUNSHIN and the database it generates, the refinement of the updated Haumea family, a brief search for other possible clusterings in the outer solar system, and the potential of our research to aid other dynamicists.

  19. Statistics of the outer radiation belt

    International Nuclear Information System (INIS)

    Rodgers, D.J.; Johnstone, A.D.

    1996-01-01

    The highly variable electron flux levels in the outer radiation belt come about by competition between time-dependent source and loss mechanisms. In order to identify some of the different mechanisms involved, we examine the statistics of the variability of fluxes at geostationary orbit. Data from the SEM-2 analyzer on Meteosat-3 and from GOES-7 are used. Correlation analysis is used to find time-delays between changes in flux at different energies. We see that low energy flux is added to this region during sub-storms and that higher energy fluxes appear after 2 or 3 days. Whilst the timescale for this process is brief compared to a complete cycle of the open-quote Recirculation close-quote energization process, it is consistent with the timescale of its final step endash outward radial diffusion. By isolating periods when no new injection of plasma occurs, we make an assessment of flux loss rates in a quiet magnetosphere. copyright 1996 American Institute of Physics

  20. Two Belts, One Road? - The role of Africa in Chinas's Belt & Road initiative

    OpenAIRE

    Breuer, Julia

    2017-01-01

    In the light of the EU-Africa Summit 2017 and of the G20 Summit 2017 with Africa being one of the focus areas, China’s engagement in Africa seems more relevant than ever. China’s “One Belt, One Road” initiative (OBOR) or silk road initiative is often referred to as a Eurasian infrastructure network initiative, but it is in fact much more than that. The maritime silk road is supposed to go past the coast of East Africa, where several ports are being built and will be built. Furthermore, ports ...

  1. Scheelite distribution a long of amphibolitic belt from greenstone belt Barbacena, Minas Gerais, Brazil

    International Nuclear Information System (INIS)

    Pereira, R.M.; Alexandre, C.A.

    1990-01-01

    In the middle southern portion of the Minas Gerais state a 60 Km long and 12 Km wide tungsten belt was discovered, and related to the amphibolitic rocks of the Barbacena Greenstone. Tungsten, present as scheelite, is associated with amphibolites, amphibole schists and amphibole gneisses, with chemical characteristics indicating an igneous origin. Chemical analyses on pan concentrates by I.C.P. showed high values on lead, tin, yttrium, lanthanum, cerium and zirconium, and average values for zinc and copper. The scheelite mineralization is probably strata bound and has a possible submarine exhalative origin. (author)

  2. Selection of Belt Conveyors Drive Units Number by Technical –Economical Analysis

    OpenAIRE

    Despodov, Zoran; Mijalkovski, Stojance; Adjiski, Vancho; Panov, Zoran

    2014-01-01

    In this paper is presented a methodology for selection of belt conveyor drive units number by technical - economical analysis of their parameters. Belt Conveyors with follow drive arrangement will be considered: one, two, three and four drive units. In the technical - economical analysis are including: Tension forces, Power of belt conveyor, Costs for belt, Costs for power and reducers, Total cost for belt conveyor system.

  3. Modeling and energy efficiency optimization of belt conveyors

    International Nuclear Information System (INIS)

    Zhang, Shirong; Xia, Xiaohua

    2011-01-01

    Highlights: → We take optimization approach to improve operation efficiency of belt conveyors. → An analytical energy model, originating from ISO 5048, is proposed. → Then an off-line and an on-line parameter estimation schemes are investigated. → In a case study, six optimization problems are formulated with solutions in simulation. - Abstract: The improvement of the energy efficiency of belt conveyor systems can be achieved at equipment and operation levels. Specifically, variable speed control, an equipment level intervention, is recommended to improve operation efficiency of belt conveyors. However, the current implementations mostly focus on lower level control loops without operational considerations at the system level. This paper intends to take a model based optimization approach to improve the efficiency of belt conveyors at the operational level. An analytical energy model, originating from ISO 5048, is firstly proposed, which lumps all the parameters into four coefficients. Subsequently, both an off-line and an on-line parameter estimation schemes are applied to identify the new energy model, respectively. Simulation results are presented for the estimates of the four coefficients. Finally, optimization is done to achieve the best operation efficiency of belt conveyors under various constraints. Six optimization problems of a typical belt conveyor system are formulated, respectively, with solutions in simulation for a case study.

  4. On-conveyor belt determination of ash in coal

    International Nuclear Information System (INIS)

    Sowerby, B.; Lim, C.S.; Abernethy, D.A.; Liu, Y.; Maguire, P.A.

    1997-01-01

    A laboratory feasibility study has been carried out on new and advanced neutron and gamma-ray analysis systems for the direct on-conveyor belt analysis of ash in coal without the need for sample by-lines. Such an analysis system could deliver the combined advantages of a direct on-conveyor configuration with new and accurate analysis techniques. An industry survey of 18 coal companies carried out in early 1996 indicated that accurate on-belt ash analysis is of the highest priority. Subsequent laboratory work has focussed on the investigation of methods with the potential for improving the accuracy of ash content measurement relative to existing on-belt ash analysers, the most widely-used of which are based on dual energy gamma-ray transmission (DUET), which is sensitive to variations in ash composition. The current work indicates that on-belt neutron/gamma-ray techniques combined with advanced spectral analysis techniques show promise for development into an on-belt ash analysis system which is significantly less sensitive to composition changes than DUET and which analyses a much larger proportion of coal on the belt, thus eliminating some key sources of analysis error

  5. Gold deposits in the Xiaoqinling-Xiong'ershan region, Qinling mountains, central China

    Science.gov (United States)

    Mao, J.; Goldfarb, R.J.; Zhang, Z.; Xu, W.; Qiu, Yumin; Deng, J.

    2002-01-01

    The gold-rich Xiaoqinling-Xiong'ershan region in eastern Shaanxi and western Henan provinces, central China, lies about 30-50 km inland of the southern margin of the North China craton. More than 100 gold deposits and occurrences are concentrated in the Xiaoqinling (west), Xiaoshan (middle), and Xiong'ershan (east) areas. Late Archean gneiss of the Taihua Group, and Middle Proterozoic metavolcanic rocks of the Xiong'er Group are the main host rocks for the deposits. Mesozoic granitoids (ca. 178-104 Ma) are present in most gold districts, but deposits are typically hosted in the Precambrian basement rocks hundreds of meters to as far as 10 km from the intrusions and related hornfels zones. Deposits in the Xiaoqinling and Xiaoshan areas are best classified as orogenic gold deposits, with ores occurring in a number of distinct belts both in quartz veins and disseminated in altered metamorphic rocks. Alteration assemblages are dominated by quartz, sericite, pyrite, and carbonate minerals. The ore-forming fluids were low salinity, CO2-rich, and characterized by isotopically heavy ??18O. Four deposits (Dongchuang, Wenyu, Yangzhaiyu, and Dahu) in the Xiaoqinling area each contain resources of about 1 Moz Au. Some of the gold deposits in the Xiong'ershan area represent more shallowly emplaced tellurium-enriched orogenic systems, which include resources of approximately 1-1.5 Moz Au at Shanggong and Beiling (or Tantou). Others are epithermal deposits (e.g., Qiyugou and Dianfang) that are hosted in volcanic breccia pipes. Isotopic dates for all gold deposits, although often contradictory, generally cluster between 172-99 Ma and are coeval with emplacement of the post-kinematic granitoids. The gold deposits formed during a period of relaxation of far-field compressional stresses, clearly subsequent to the extensive Paleozoic-early Mesozoic accretion of are terranes and the Yangtze craton onto the southern margin of the North China craton. Hydrothermal and magmatic events

  6. Structure and bonding in gold compounds

    International Nuclear Information System (INIS)

    Parish, R.V.

    1988-01-01

    Recent developments in chemical applications of 197 Au Moessbauer spectroscopy are reviewed. For gold(I) and gold(III), systematic variations in isomer shift and quadrupole splitting are seen as the ligands are changed; the effects of change in coordination number of the gold atoms are also systematic. Data for gold(II) systems involving gold-gold bonds lie between those for corresponding gold(I) and gold(III) materials, showing a small increase in isomer shift and a larger increase in quadrupole splitting as the oxidation state decreases; these trends are explained in terms of the structures. Data for mixed-metal cluster compounds are much more sensitive to structural effects than in homonuclear clusters. Both sets of data show systematic changes with increase in the number of metal atoms to which the gold atom is bound. The connectivity also influences the recoil-free fraction. (orig.)

  7. A new indicator mineral methodology based on a generic Bi-Pb-Te-S mineral inclusion signature in detrital gold from porphyry and low/intermediate sulfidation epithermal environments in Yukon Territory, Canada

    Science.gov (United States)

    Chapman, R. J.; Allan, M. M.; Mortensen, J. K.; Wrighton, T. M.; Grimshaw, M. R.

    2017-12-01

    Porphyry-epithermal and orogenic gold are two of the most important styles of gold-bearing mineralization within orogenic belts. Populations of detrital gold resulting from bulk erosion of such regions may exhibit a compositional continuum wherein Ag, Cu, and Hg in the gold alloy may vary across the full range exhibited by natural gold. This paper describes a new methodology whereby orogenic and porphyry-epithermal gold may be distinguished according to the mineralogy of microscopic inclusions observed within detrital gold particles. A total of 1459 gold grains from hypogene, eluvial, and placer environments around calc-alkaline porphyry deposits in Yukon (Nucleus-Revenue, Casino, Sonora Gulch, and Cyprus-Klaza) have been characterized in terms of their alloy compositions (Au, Ag, Cu, and Hg) and their inclusion mineralogy. Despite differences in the evolution of the different magmatic hydrothermal systems, the gold exhibits a clear Bi-Pb-Te-S mineralogy in the inclusion suite, a signature which is either extremely weak or (most commonly) absent in both Yukon orogenic gold and gold from orogenic settings worldwide. Generic systematic compositional changes in ore mineralogy previously identified across the porphyry-epithermal transition have been identified in the corresponding inclusion suites observed in samples from Yukon. However, the Bi-Te association repeatedly observed in gold from the porphyry mineralization persists into the epithermal environment. Ranges of P-T-X conditions are replicated in the geological environments which define generic styles of mineralization. These parameters influence both gold alloy composition and ore mineralogy, of which inclusion suites are a manifestation. Consequently, we propose that this methodology approach can underpin a widely applicable indicator methodology based on detrital gold.

  8. The Archaen volcanic facies in the Migori segment, Nyanza greenstone belt, Kenya: stratigraphy, geochemistry and mineralisation

    Science.gov (United States)

    Ichang'l, D. W.; MacLean, W. H.

    The Migori segment is an 80 by 20 km portion of the Nyanza greenstone belt which forms the northern part of the Archean Tanzanian Craton in western Kenya, northern Tanzania and southeastern Uganda. It consists of two volcanic centres, each with central, proximal and distal volcanic facies, comprising the Migori Group, the Macalder and Lolgorien Subgroups, and eleven volcano-sedimentary formations. The centres are separated by a basin of tuffs and greywacke turbidites. The volcanics are bimodal mafic basalt and dolerite ( Zr/Y = 3.8 - 6.5, La N/Yb N = 1.0 - 2.4) , and felsic calc-alkaline dacite-rhyolite ( Zr/Y = 10 - 21, La N/Yb N = 19 - 42 ) and high-K dacite ( Zr/Y = 9 - 16, La N/Yb N = 21 - 22 ). Felsic units form approximately three-fourths of the volcanic stratigraphy. Basalts, calc-alkaline dacites and rhyolites were deposited in a submarine environment, but the voluminous high-K dacites were erupted subaerially. The turbidites contain units of iron-formations. Granitic intrusions are chemically continuous with the high-K dacites. The felsic volcanics are anologous to those found at modern volcanic arc subduction settings involving continental crust. The Macalder ZnCuAuAg volcanogenic massive sulphide deposits is in central facies basalts-greywacke-rhyolite. Gold mineralisation occurs in proximal facies tuffs and iron formation, and in oblique and semi-conformable quartz veins. Greenstones in the Nyanza belt are dominated by calc-alkaline felsic volcanics in constrast to the komatiite-tholeiitic basalt volcanism in the Kaapvaal Craton of South Africa, and a mixture of the two types in the Zimbabwe Craton.

  9. Deformation and kinematics of the central Kirthar Fold Belt, Pakistan

    Science.gov (United States)

    Hinsch, Ralph; Hagedorn, Peter; Asmar, Chloé; Nasim, Muhammad; Aamir Rasheed, Muhammad; Kiely, James M.

    2017-04-01

    The Kirthar Fold Belt is part of the lateral mountain belts in Pakistan linking the Himalaya orogeny with the Makran accretionary wedge. This region is deforming very oblique/nearly parallel to the regional plate motion vector. The study area is situated between the prominent Chaman strike-slip fault in the West and the un-deformed foreland (Kirthar Foredeep/Middle Indus Basin) in the East. The Kirthar Fold Belt is subdivided into several crustal blocks/units based on structural orientation and deformation style (e.g. Kallat, Khuzdar, frontal Kirthar). This study uses newly acquired and depth-migrated 2D seismic lines, surface geology observations and Google Earth assessments to construct three balanced cross sections for the frontal part of the fold belt. Further work was done in order to insure the coherency of the built cross-sections by taking a closer look at the regional context inferred from published data, simple analogue modelling, and constructed regional sketch sections. The Khuzdar area and the frontal Kirthar Fold Belt are dominated by folding. Large thrusts with major stratigraphic repetitions are not observed. Furthermore, strike-slip faults in the Khuzdar area are scarce and not observed in the frontal Kirthar Fold Belt. The regional structural elevation rises from the foreland across the Kirthar Fold Belt towards the hinterland (Khuzdar area). These observations indicate that basement-involved deformation is present at depth. The domination of folding indicates a weak decollement below the folds (soft-linked deformation). The fold pattern in the Khuzdar area is complex, whereas the large folds of the central Kirthar Fold Belt trend SSW-NNE to N-S and are best described as large detachment folds that have been slightly uplifted by basement involved transpressive deformation underneath. Towards the foreland, the deformation is apparently more hard-linked and involves fault-propagation folding and a small triangle zone in Cretaceous sediments

  10. Annealing relaxation of ultrasmall gold nanostructures

    Science.gov (United States)

    Chaban, Vitaly

    2015-01-01

    Except serving as an excellent gift on proper occasions, gold finds applications in life sciences, particularly in diagnostics and therapeutics. These applications were made possible by gold nanoparticles, which differ drastically from macroscopic gold. Versatile surface chemistry of gold nanoparticles allows coating with small molecules, polymers, biological recognition molecules. Theoretical investigation of nanoscale gold is not trivial, because of numerous metastable states in these systems. Unlike elsewhere, this work obtains equilibrium structures using annealing simulations within the recently introduced PM7-MD method. Geometries of the ultrasmall gold nanostructures with chalcogen coverage are described at finite temperature, for the first time.

  11. Phage based green chemistry for gold ion reduction and gold retrieval.

    Science.gov (United States)

    Setyawati, Magdiel I; Xie, Jianping; Leong, David T

    2014-01-22

    The gold mining industry has taken its toll on the environment, triggering the development of more environmentally benign processes to alleviate the waste load release. Here, we demonstrate the use of bacteriophages (phages) for biosorption and bioreduction of gold ions from aqueous solution, which potentially can be applied to remediate gold ions from gold mining waste effluent. Phage has shown a remarkably efficient sorption of gold ions with a maximum gold adsorption capacity of 571 mg gold/g dry weight phage. The product of this phage mediated process is gold nanocrystals with the size of 30-630 nm. Biosorption and bioreduction processes are mediated by the ionic and covalent interaction between gold ions and the reducing groups on the phage protein coat. The strategy offers a simple, ecofriendly and feasible option to recover of gold ions to form readily recoverable products of gold nanoparticles within 24 h.

  12. On-conveyor belt analysis of coal

    Energy Technology Data Exchange (ETDEWEB)

    Cheryl Lim; David Abernethy; S. Rainey; L.K. Noack [CSIRO Minerals (Australia)

    2007-09-15

    The report describes the design and plant-testing of a prototype commercial on-belt ash analyser at the Bengalla CHPP (Muswellbrook, NSW). This analyser uses the Neutron Inelastic Scatter (NIS) and Thermal Neutron Capture (TNC) Analysis (NITA) technique, which has been investigated extensively in earlier ACARP projects C5051 (laboratory feasibility study) and the previous stage of C9042 (development and lab testing of a field prototype and evaluate the suitability of the technique for specific energy and sulphur measurement). The NITA analyser has been demonstrated to be capable of achieving an accuracy of 0.46 %ash. Specifically, a measured value for total r.m.s. error of 0.77 %ash, measured r.m.s error includes various uncertainties (estimated to be 0.61 %ash) associated with the chemical analysis and sample collection procedures used to generate the chemical laboratory data provided for calibration. In earlier laboratory work it was demonstrated that a measured r.m.s error of 0.75 %ash corresponded to an actual accuracy of 0.53 %ash after much smaller laboratory sampling errors had been excluded. Accurate measurement of ash value can be achieved in material which is expected to have significant variability in mineralogy, and in the past has not been amenable to analysis using the DUET technique. Accurate measurement of ash value is possible in the presence of significant levels of segregation and changes in mineral matter composition. CSIRO is collaborating with a commercial partner to demonstrate and complete the implementation of the NITA technology in industry. A commercial prototype analyser (NITA II) is under development and a plant installation is expected to occur in mid 2008.

  13. Geology, geochemistry, and geochronology of the East Bay gold trend, Red Lake, Ontario, Canada

    Science.gov (United States)

    Gallagher, Shaun; Camacho, Alfredo; Fayek, Mostafa; Epp, Mark; Spell, Terry L.; Armstrong, Richard

    2018-01-01

    The Red Lake greenstone belt is situated in northwestern Ontario within the Uchi Subprovince, Superior Province. Most gold deposits therein are associated with major deformation corridors; the east-west oriented "Mine trend" hosts most of the large deposits and the northeast-southwest "East Bay trend" hosts several small deposits and showings. Gold along the East Bay trend typically occurs in quartz replacement veins that were emplaced into pre-existing quartz-carbonate veins. Gold can occur as free gold or along vein margins associated with pyrite and pyrrhotite. Most primary fluid inclusions, preserved in relatively undeformed portions of veins, are carbonaceous with lesser quantities of aqueous inclusions. The average homogenization temperature of aqueous fluids is 250 °C; however, the abundance of three-phase inclusions, variation in liquid-vapor ratios, and a wide range in homogenization temperatures indicate that immiscibility, effervescence, and fluid mixing are mechanisms associated with gold deposition. The age ( 2550 Ma) of alteration minerals in the Abino area is considerably younger (by 100 Myr) than alteration minerals in other deposits in the Red Lake district, indicating that the mineralizing fluid history was more protracted than previously thought. Along the East Bay trend, barren veins generally have lower δ18OVSMOW values (0.0 to 8.5‰) relative to auriferous veins (9.6 and 13.1‰). Consequently, the oxygen isotopic composition of quartz could be used as a vector for gold mineralization. The genetic model for the East Bay trend involves several stages of vein formation. Auriferous veins formed near the upper boundary of the mesozonal regime (depth of 5-6 km).

  14. Geochemical Characteristics of Metamorphic Rock-Hosted Gold Deposit At Onzon-Kanbani Area, Central Myanmar

    Directory of Open Access Journals (Sweden)

    Aung Tay Zar

    2017-09-01

    Full Text Available Gold and associated base metal mineralization of Onzon-Kabani area located in the western border of generally N-S trending Mogoke Metamorphic Belt where well-known Sagaing fault is served as a western boundary of this area. In this research area, many artisanal and small-scale gold mines were noted in last three decades. Gold mineralization is hosted in marble and gneiss unit of research area but most common in marble unit. Variety of igneous intrusions are also observed in research area. Mineralizations are observed as fissure filling veins as well as lesser amount of disseminated nature in marble unit. Mineralogically, gold are associated with other base metal such as pyrite, galena, sphalerite, chalcopyrite, marcasite and arsenopyrite. Hydrothermal alteration halos are developed in peripheral of hydrothermal conduits or mineralization veins from proximal to distal such as 1 silicic, 2 sericite-illite, and 3 propylitic alteration.  Most of hydrothermal minerals from each altered zones showed that near neutral condition of pH (e.g. adularia, calcite, illite, sericite and chlorite. Alternatively, hydrothermal alteration zones that show with ore minerals such as native gold, electrum, sphalerite, galena, chalcopyrite, arsenopyrite and marcasite which mostly observed in silicic alteration zone. Typical boiling characters of vein textures and fluid inclusion petrography are observed in hydrothermal system of research area. Boiling, cooling and mixing are possiblily responsible for gold deposition in hydrothermal system. In this paper, authors are documented to clarify the type of mineralization based on hydrothermal alterations, ore and gangue mineral assemblages and fluid inclusion study. All of these data can describe and play an important role for both with respect to understanding deposit genesis and in mineral exploration.

  15. Meningococcal carriage in the African meningitis belt

    Science.gov (United States)

    2013-01-01

    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent the acquisition of pharyngeal carriage as well as invasive meningococcal disease and whether PsA-TT can prevent pharyngeal carriage needs to be determined. To address this issue, a consortium (the African Meningococcal Carriage (MenAfriCar) consortium) was established in 2009 to investigate the pattern of meningococcal carriage in countries of the African meningitis belt prior to and after the introduction of PsA-TT. This article describes how the consortium was established, its objectives and the standardised field and laboratory methods that were used to achieve these objectives. The experience of the MenAfriCar consortium will help in planning future studies on the epidemiology of meningococcal carriage in countries of the African meningitis belt and elsewhere. Un vaccin conjugué contenant un polysaccharide du sérogroupe A méningococcique et une anatoxine du tétanos (PsA-TT) (MenAfriVac™) est en cours de déploiement dans les pays de la ceinture africaine de la méningite. L’ expérience avec d’ autres vaccins conjugués polysaccharide/protéine a montré qu’ une partie importante de leur succès a été leur capacité à empêcher l’ acquisition du portage pharyngé et donc à arrêter la transmission et à induire une immunité de group. Si PsA-TT doit d’ atteindre l’ objectif de prévenir les épidémies, il devrait être en mesure d’ empêcher l’ acquisition du portage pharyngé ainsi que la méningococcie invasive et le fait que PsA-TT puisse emp

  16. Lithogeochemistry of Carlin-type gold mineralization in the Gold Bar district, Battle Mountain-Eureka trend, Nevada

    Science.gov (United States)

    Yigit, O.; Hofstra, A.H.

    2003-01-01

    , consisting of X-Y plots of SiO2/Al2O3, K2O/Al2O3, CO2/Al2O3, that documented in classic Carlin-type gold deposits in the region, but the size of the deposits and the intensity of alteration and mineralization are less. The presence of other types of mineralization in the Gold Bar district is also common to most of the other Carlin-type districts located in major mineral belts. The approach used in this study is well suited to the interpretation of multi-element geochemical data from other study areas with superimposed alteration and mineralization. ?? 2002 Elsevier Science B.V. All rights reserved.

  17. Gold nanoparticles stabilized by chitosan

    International Nuclear Information System (INIS)

    Geraldes, Adriana N.; Oliveira, Maria Jose A.; Silva, Andressa A. da; Leal, Jessica; Batista, Jorge G.S.; Lugao, Ademar B.

    2015-01-01

    In our laboratory has been growing the interest in studying gold nanoparticles and for this reason, the aim of this work is report the first results of the effect of chitosan as stabilizer in gold nanoparticle formulation. AuNPs were synthesized by reducing hydrogen tetrachloroaurate (HAuCl 4 ) using NaBH 4 or gamma irradiation (25kGy) as reduction agent. The chitosan (3 mol L -1 ) was added at 0.5; 1.0 and 1.5 mL. The gold nanoparticles were characterized by UV-Vis absorption spectroscopy, X-ray diffraction (XRD) and Transmission electron microscopy (TEM). Their physical stability was determined using a UV-Vis spectrophotometer over one week during storage at room temperature. Absorption measurements indicated that the plasmon resonance wavelength appears at a wavelength around 530 nm. Has been observed that Chitosan in such quantities were not effective in stabilizing the AuNPs. (author)

  18. Geological characteristics of dike-structural belt in Taoshan orefield and its relationship to uranium deposits

    International Nuclear Information System (INIS)

    Zhang Wanliang; Zou Maoqing; Shao Fei; Nie Bin

    2009-01-01

    Taoshan uranium field is occurred in the Taoshan composite batholith in the central Jiangxi Province. The main body of the batholith was formed in Triassic-Early Cretaceous. In Late Cretaceous-Eogene, NE strike fault structure and dike belt were developed in the batholith. From the north to the south, there are successive Xiaobu-Matian dike-structural belt, Wangnitian dike- structural belt, Huangtan-Yueyuan dike-structural belt, Xibei-Shangluo dike-structural belt, Jipoling dike-structural belt, Wangce dike-structural belt and Shiyuanling dike-structural belt. These belts are controlled by the main fault, share the same space and similar time with the uranium mineralization, which is one of the important factors in positioning the uranium ore as well as the prospecting direction of exploration. (authors)

  19. Plasmonic Horizon in Gold Nanosponges.

    Science.gov (United States)

    Vidal, Cynthia; Sivun, Dmitry; Ziegler, Johannes; Wang, Dong; Schaaf, Peter; Hrelescu, Calin; Klar, Thomas A

    2018-02-14

    An electromagnetic wave impinging on a gold nanosponge coherently excites many electromagnetic hot-spots inside the nanosponge, yielding a polarization-dependent scattering spectrum. In contrast, a hole, recombining with an electron, can locally excite plasmonic hot-spots only within a horizon given by the lifetime of localized plasmons and the speed carrying the information that a plasmon has been created. This horizon is about 57 nm, decreasing with increasing size of the nanosponge. Consequently, photoluminescence from large gold nanosponges appears unpolarized.

  20. New Trends in Gold Catalysts

    Directory of Open Access Journals (Sweden)

    Leonarda F. Liotta

    2014-07-01

    Full Text Available Gold is an element that has fascinated mankind for millennia. The catalytic properties of gold have been a source of debate, due to its complete chemical inertness when in a bulk form, while it can oxidize CO at temperatures as low as ~200 K when in a nanocrystalline state, as discovered by Haruta in the late 1980s [1]. Since then, extensive activity in both applied and fundamental research on gold has been initiated. The importance of the catalysis by gold represents one of the fasted growing fields in science and is proven by the promising applications in several fields, such as green chemistry and environmental catalysis, in the synthesis of single-walled carbon nanotubes, as modifiers of Ni catalysts for methane steam and dry reforming reactions and in biological and electrochemistry applications. The range of reactions catalyzed by gold, as well as the suitability of different supports and the influence of the preparation conditions have been widely explored and optimized in applied research [2]. Gold catalysts appeared to be very different from the other noble metal-based catalysts, due to their marked dependence on the preparation method, which is crucial for the genesis of the catalytic activity. Several methods, including deposition-precipitation, chemical vapor deposition and cation adsorption, have been applied for the preparation of gold catalysts over reducible oxides, like TiO2. Among these methods, deposition-precipitation has been the most frequently employed method for Au loading, and it involves the use of tetrachloroauric (III acid as a precursor. On the other hand, the number of articles dealing with Au-loaded acidic supports is smaller than that on basic supports, possibly because the deposition of [AuCl4]− or [AuOHxCl4−x]− species on acidic supports is difficult, due to their very low point of zero charge. Despite this challenge, several groups have reported the use of acidic zeolites as supports for gold. Zeolites

  1. A Novel Strategy for Synthesis of Gold Nanoparticle Self Assemblies

    NARCIS (Netherlands)

    Verma, Jyoti; Lal, Sumit; van Veen, Henk A.; van Noorden, Cornelis J. F.

    2014-01-01

    Gold nanoparticle self assemblies are one-dimensional structures of gold nanoparticles. Gold nanoparticle self assemblies exhibit unique physical properties and find applications in the development of biosensors. Methodologies currently available for lab-scale and commercial synthesis of gold

  2. Geochemical evidence for subduction in the early Archaean from quartz-carbonate-fuchsite mineralization, Isua Supracrustal Belt, West Greenland

    DEFF Research Database (Denmark)

    Pope, Emily Catherine; Rosing, Minik Thorleif; Bird, Dennis K.

    Quartz, carbonate and fuchsite (chromian muscovite) is a common metasomatic assemblage observed in orogenic gold systems, both in Phanerozoic convergent margin settings, and within supracrustal and greenstone belts of Precambrian rocks. Geologic and geochemical observations in younger orogenic...... systems suggest that ore-forming metasomatic fluids are derived from subduction-related devolitilization reactions, implying that orogenic Au-deposits in Archaean and Proterozoic supracrustal rock suites are related to subduction-style plate tectonics beginning early in Earth history. Justification...... with Phanerozoic orogenic deposits and that this type of metasomatism is a unique result of subduction-related processes. Fuchsite from the ISB has a δ18O and δD of 7.7 to 17.9‰ and -115 to -61‰, respectively. δ18O of quartz from the same rocks is between 10.3 and 18.6‰. Muscovite-quartz oxygen isotope thermometry...

  3. Ligations of Gold Atoms with Iron Porphyrin

    DEFF Research Database (Denmark)

    Zhang, Ling; Kepp, Kasper Planeta; Ulstrup, Jens

    Gold is an exotic material with d-electrons deciding electronic mappings andconfigurations of adsorbed molecules. The specific interaction of Au atoms and S-, Ncappedmolecules make gold nanoparticles widely applied in the medicine transport andimmunoassay. Density functional theory demonstrates t...

  4. Metallic gold beads in hyaluronic acid

    DEFF Research Database (Denmark)

    Pedersen, Dan Sonne; Tran, Thao Phuong; Smidt, Kamille

    2013-01-01

    . In conclusion, our findings support that bio-liberation of gold from metallic gold surfaces have anti-inflammatory properties similar to classic gold compounds, warranting further studies into the pharmacological potential of this novel gold-treatment and the possible synergistic effects of hyaluronic acid....... by exploiting macrophage-induced liberation of gold ions (dissolucytosis) from gold surfaces. Injecting gold beads in hyaluronic acid (HA) as a vehicle into the cavities of the brain can delay clinical signs of disease progression in the MS model, experimental autoimmune encephalitis (EAE). This study...... investigates the anti-inflammatory properties of metallic gold/HA on the gene expression of tumor necrosis factor (Tnf-α), Interleukin (Il)-1β, Il-6, Il-10, Colony-stimulating factor (Csf)-v2, Metallothionein (Mt)-1/2, Bcl-2 associated X protein (Bax) and B cell lymphoma (Bcl)-2 in cultured J774 macrophages...

  5. PRESENTDAY STRESS STATE OF THE SHANXI TECTONIC BELT

    Directory of Open Access Journals (Sweden)

    Wang Kaiying

    2012-01-01

    Full Text Available The Shanxi tectonic belt is a historically earthquakeabundant area. For the majority of strong earthquakes in this area, the distribution of earthquake foci was controlled by the N–S oriented local structures on the tectonic belt. Studies of the present stress state of the Shanxi tectonic belt can contribute to the understanding of the relationship between strong earthquakes’ occurrence and their structural distribution and also facilitate assessments of regional seismic danger and determination of the regions wherein strong earthquakes may occur in future. Using the Cataclastic Analysis Method (CAM, we performed stress inversion based on the focal mechanism data of earthquakes which took place in the Shanxi tectonic belt from 1967 to 2010. Our results show that orientations of the maximum principal compressive stress axis of the Shanxi tectonic belt might have been variable before and after the 2001 Kunlun MS=8.1 strong earthquake, with two different superior trends of the NW–SE and NE–SW orientation in different periods. When the maximum principal compressive stress axis is oriented in the NE–SW direction, the pattern of the space distribution of the seismic events in the Shanxi tectonic belt shows a trend of their concentration in the N–S oriented tectonic segments. At the same time, the stress state is registered as horizontal shearing and horizontal extension in the N–S and NE–SW oriented local segments in turn. When the maximum principal compressive stress axis is NW–SE oriented, the stress state of the N–S and NE–SW oriented tectonic segments is primarily registered as horizontal shearing. Estimations of plunges of stress axes show that seismicity in the Shanxi belt  corresponds primarily to the activity of lowangle faults, and highangle stress sites are located in the NE–SW oriented extensional tectonic segments of the Shanxi belt. This indicates that the stress change of the Shanxi belt is

  6. Survey of current situation in radiation belt modeling

    Science.gov (United States)

    Fung, Shing F.

    2004-01-01

    The study of Earth's radiation belts is one of the oldest subjects in space physics. Despite the tremendous progress made in the last four decades, we still lack a complete understanding of the radiation belts in terms of their configurations, dynamics, and detailed physical accounts of their sources and sinks. The static nature of early empirical trapped radiation models, for examples, the NASA AP-8 and AE-8 models, renders those models inappropriate for predicting short-term radiation belt behaviors associated with geomagnetic storms and substorms. Due to incomplete data coverage, these models are also inaccurate at low altitudes (e.g., <1000 km) where many robotic and human space flights occur. The availability of radiation data from modern space missions and advancement in physical modeling and data management techniques have now allowed the development of new empirical and physical radiation belt models. In this paper, we will review the status of modern radiation belt modeling. Published by Elsevier Ltd on behalf of COSPAR.

  7. Angle stations in or for endless conveyor belts

    Science.gov (United States)

    Steel, Alan

    1987-04-07

    In an angle station for an endless conveyor belt, there are presented to each incoming run of the belt stationary curved guide members (18, 19) of the shape of a major segment of a right-circular cylinder and having in the part-cylindrical portion (16 or 17) thereof rectangular openings (15) arranged in parallel and helical paths and through which project small freely-rotatable rollers (14), the continuously-changing segments of the curved surfaces of which projecting through said openings (15) are in attitude to change the direction of travel of the belt (13) through 90.degree. during passage of the belt about the part-cylindrical portion (16 or 17) of the guide member (18 or 19). The rectangular openings (15) are arranged with their longer edges lengthwise of the diagonals representing the mean of the helix but with those of a plurality of the rows nearest to each end of the part-cylindrical portion (16 or 17) slightly out of axial symmetry with said diagonals, being slightly inclined in a direction about the intersections (40) of the diagonals of the main portion of the openings, to provide a "toe-in" attitude in relation to the line of run of the endless conveyor belt.

  8. Energy-saving belt conveyors installed in Polish collieries

    Directory of Open Access Journals (Sweden)

    Jerzy ANTONIAK

    2010-01-01

    Full Text Available An important problem of reducing energy consumption and dioxide emissions in the stage of construction and operation of mine belt conveyors is connected with their broad use in the industry. However, this notion is related to a reduction of electric energy consumption for conveyor drive and for production of conveyor components and assemblies (belts, rollers, load-bearing structure etc.. An essential role is played by an increased life of belt conveyors assemblies and components, principally belts. A reduced electric energy consumption results in a decreased CO2 emissions, e.g. hard coal – fired power station issues 0.28 kg CO2 per production of 1 kWh, in to answer production of 1 t steel accounts for 3.2 t CO2 emissions. The subject-matter presented in the paper concerning energy-saving in the horizontally and inclined mine belt conveyors installed in a Polish colliery – Anna, Jankowice and Marcel, has a big economic significance and it is important from the point of view of environmental protection.

  9. Fall Protection Characteristics of Safety Belts and Human Impact Tolerance.

    Science.gov (United States)

    Hino, Yasumichi; Ohdo, Katsutoshi; Takahashi, Hiroki

    2014-08-23

    Many fatal accidents due to falls from heights have occurred at construction sites not only in Japan but also in other countries. This study aims to determine the fall prevention performance of two types of safety belts: a body belt 1) , which has been used for more than 40 yr in the Japanese construction industry as a general type of safety equipment for fall accident prevention, and a full harness 2, 3) , which has been used in many other countries. To determine human tolerance for impact trauma, this study discusses features of safety belts with reference 4-9) to relevant studies in the medical science, automobile crash safety, and aircrew safety. For this purpose, simple drop tests were carried out in a virtual workplace to measure impact load, head acceleration, and posture in the experiments, the Hybrid-III pedestrian model 10) was used as a human dummy. Hybrid-III is typically employed in official automobile crash tests (New Car Assessment Program: NCAP) and is currently recognized as a model that faithfully reproduces dynamic responses. Experimental results shows that safety performance strongly depends on both the variety of safety belts used and the shock absorbers attached onto lanyards. These findings indicate that fall prevention equipment, such as safety belts, lanyards, and shock absorbers, must be improved to reduce impact injuries to the human head and body during falls.

  10. Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization

    Science.gov (United States)

    Daglis, I.; Balasis, G.; Bourdarie, S.; Horne, R.; Khotyaintsev, Y.; Mann, I.; Santolik, O.; Turner, D.; Anastasiadis, A.; Georgiou, M.; Giannakis, O.; Papadimitriou, C.; Ropokis, G.; Sandberg, I.; Angelopoulos, V.; Glauert, S.; Grison, B., Kersten T.; Kolmasova, I.; Lazaro, D.; Mella, M.; Ozeke, L.; Usanova, M.

    2013-09-01

    We present the concept, objectives and expected impact of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, which is being implemented by a consortium of seven institutions (five European, one Canadian and one US) with support from the European Community's Seventh Framework Programme. The MAARBLE project employs multi-spacecraft monitoring of the geospace environment, complemented by ground-based monitoring, in order to analyze and assess the physical mechanisms leading to radiation belt particle energization and loss. Particular attention is paid to the role of ULF/VLF waves. A database containing properties of the waves is being created and will be made available to the scientific community. Based on the wave database, a statistical model of the wave activity dependent on the level of geomagnetic activity, solar wind forcing, and magnetospheric region will be developed. Multi-spacecraft particle measurements will be incorporated into data assimilation tools, leading to new understanding of the causal relationships between ULF/VLF waves and radiation belt dynamics. Data assimilation techniques have been proven as a valuable tool in the field of radiation belts, able to guide 'the best' estimate of the state of a complex system. The MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Energization and Loss) collaborative research project has received funding from the European Union’s Seventh Framework Programme (FP7-SPACE-2011-1) under grant agreement no. 284520.

  11. On the existence of a comet belt beyond Neptune

    International Nuclear Information System (INIS)

    Fernandez, J.A.

    1980-01-01

    The possible existence of a comet belt in connection with the origin of the short-period comets is analysed. It is noted that the current theory - that these comets originate as near-parabolic comets captured by Jupiter and the other giant planets - implies an excessive wastage of comets lost in hyperbolic orbits, which is avoided in the present model. The following picture is predicted. Solid conglomerates up to approximately 10 18 g were formed by gravitational instabilities in the belt region (about 35 to 50 AU). A further fragmentation-accretion process led to a power-law mass distribution similar to that observed in the asteroids. Since then, close encounters between members of the belt have provoked the diffusion of some of them with the effect that they have become subject to the strong perturbations of Neptune. Of these a small number pass from one planet to the next inside and end as short-period comets. By means of a Monte Carlo method, the influence of close encounters between belt comets is then studied in relation to the diffusion of their orbits. It is concluded that if such a belt contains members with masses equal to or greater than that of Ceres, the orbital diffusion could proceed fast enough to maintain the number of observed short-period comets in a steady state. (author)

  12. SEAT BELT USE AMONG CAR USERS IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    S. KULANTHAYAN

    2004-01-01

    Full Text Available The car is the second (40% most common mode of transportation in Malaysia. In terms of fatal road accidents, car drivers constitute about 9.0% and passengers 13.6% of fatalities. The major cause of car occupants' fatality in such accidents is head injuries, which consist of more than half (56.4% of the fatalities. Thus restraining the head and body, the initial position is the most important injury control strategy for car users. The use of seat belts was deemed one of the most effective ways to reduce road accident fatalities in Malaysia and consequently the mandatory seat belt law was enforced in the early seventies. Therefore, a study on factors influencing the compliance behaviour of seat belt use among cars is needed as to date no such research has been undertaken in Malaysia. A questionnaire study was carried out in Selangor, Malaysia on the compliance behaviour of car occupants in relation to seat belt use. A total of 237 respondents were interviewed and the data analysed using logistic regression method. Six variables were found to be significant at 5 percent level (p<0.05: seating position, location of travel, education level, speeding, night-time driving and enforcement. Compliance with the seat belt law was higher among drivers, educated car users, in the presence of enforcement activities, travelling in city-center areas and car users with a positive attitude towards the risks of speeding and night driving.

  13. Gold Nanoparticle Mediated Phototherapy for Cancer

    International Nuclear Information System (INIS)

    Yao, C.; Zhang, L.; Wang, J.; He, Y.; Xin, J.; Wang, S.; Xu, H.; Zhang, Z.

    2016-01-01

    Gold nanoparticles exhibit very unique physiochemical and optical properties, which now are extensively studied in range of medical diagnostic and therapeutic applications. In particular, gold nanoparticles show promise in the advancement of cancer treatments. This review will provide insights into the four different cancer treatments such as photothermal therapy, gold nanoparticle-aided photodynamic therapy, gold nanoparticle-aided radiation therapy, and their use as drug carrier. We also discuss the mechanism of every method and the adverse effects and its limitations

  14. Highly active thermally stable nanoporous gold catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Biener, Juergen; Wittstock, Arne; Biener, Monika M.; Bagge-Hansen, Michael; Baeumer, Marcus; Wichmann, Andre; Neuman, Bjoern

    2016-12-20

    In one embodiment, a system includes a nanoporous gold structure and a plurality of oxide particles deposited on the nanoporous gold structure; the oxide particles are characterized by a crystalline phase. In another embodiment, a method includes depositing oxide nanoparticles on a nanoporous gold support to form an active structure and functionalizing the deposited oxide nanoparticles.

  15. Gold and Silver Extraction from Leach Solutions

    OpenAIRE

    Bagdaulet K. Kenzhaliyev; Renata R. Iskhakova; Zamzagul D. Dosymbaeva; Esen N. Sulejmenov

    2014-01-01

    There has been carried out an investigation on the extraction of gold and silver from thiosulfate solutions: standard test and technological solutions of chemical and electrochemical leaching. The influence of related metals on the process of extracting gold from solution was studied. There has been conducted a comparative study of the IR spectra of solutions after the sorption of gold, silver and related metals.

  16. Cancer caused by radioactive gold rings

    International Nuclear Information System (INIS)

    Callary, E.M.

    1989-01-01

    Two recent cases of skin cancer caused by radioactive gold rings are described. The gold was contaminated with radon daughters from hollow goldseeds used to hold radon, back in the 1930s or possibly later. Other radioactive gold rings are probably being worn. The Canadian AECB offers free testing

  17. Ultrafast vibrations of gold nanorings

    DEFF Research Database (Denmark)

    Kelf, T; Tanaka, Y; Matsuda, O

    2011-01-01

    We investigate the vibrational modes of gold nanorings on a silica substrate with an ultrafast optical technique. By comparison with numerical simulations, we identify several resonances in the gigahertz range associated with axially symmetric deformations of the nanoring and substrate. We...

  18. Ultrafast vibrations of gold nanorings

    DEFF Research Database (Denmark)

    Kelf, T; Tanaka, Y; Matsuda, O

    2011-01-01

    We investigate the vibrational modes of gold nanorings on a silica substrate with an ultrafast optical technique. By comparison with numerical simulations, we identify several resonances in the gigahertz range associated with axially symmetric deformations of the nanoring and substrate. We elucid...

  19. RATIONALE FOR CENTERING CAPACITY OF REDISIGNED BELT CONVEYOR DRUMS

    Directory of Open Access Journals (Sweden)

    V. V. Suglobov

    2016-02-01

    Full Text Available Purpose. In the study is necessary: 1 to justify aligning drums of a new design of belt conveyors; 2 to develop a method for calculating and determining the rational design parameters of drums depending on the technical parameters of the conveyor belt (the length of the conveyor, belt width, the performance of the conveyor, the diameter of the drive and tension drums, etc.; 3 to carry out pilot studies of efficiency conveyor belt in a production environment in order to determine the magnitude of dynamic loads and a comparative evaluation of the effectiveness of the centering ability of conventional and new designs of drums. Methodology. To substantiate the effectiveness of the centering ability of the drums of a new design by the authors developed a mathematical model of interaction of the tape with the drum. Mathematical simulation of tape reels with new design comes to drawing up a differential equation of the belt based on the dynamic component and restoring force. This model allowed us to estimate the movement of the tape in the transverse direction based on the calculated additional dynamic loads and forces on the investigated centering a conveyor belt with given specifications. For the first time the technique of calculating and determining the rational parameters of the drums, which allows determining the design parameters of the centering portions, depending on the mechanical properties and geometric parameters of the tape. Findings. With the help of mathematical modeling the scientifically substantiated effect of centering the ability of the new design of the drum, which ensures stable tape running along the longitudinal axis of the conveyor. The authors made the following conclusions: 1 the mathematical model of interaction with the new belt design of the drum, which allowed to describe the belt in the transverse direction in view of additional dynamic loads and renewable power was developed; 2 the method of calculation and

  20. Design of a nucleonic conveyor belt weighing machine

    International Nuclear Information System (INIS)

    Magal, B.S.; Sunder Singh, V.P.

    1979-01-01

    A brief literature survey of the existing conventional units and the nucleonic belt weigher is made. The design of a 250 ton per hour coal weighing unit working in conjunction with a 24 inch wide belt, running at 350 feet per minute has been attempted and a unit has been built to the above specifications. Caseium-137 line source has been used as an isotope and a 10 litre volume argon filled ionisation chamber has been used as a detector. A line source has been preferred to a point source. The unit is under trial and the accuracy of the same is being evaluated by changing the variables like particle size profile of the material deposited on the belt and sudden changes in loading. Initial trials indicate that an accuracy of +- 1 p.c. can be achieved. (auth.)

  1. A minimalistic and optimized conveyor belt for neutral atoms.

    Science.gov (United States)

    Roy, Ritayan; Condylis, Paul C; Prakash, Vindhiya; Sahagun, Daniel; Hessmo, Björn

    2017-10-20

    Here we report of a design and the performance of an optimized micro-fabricated conveyor belt for precise and adiabatic transportation of cold atoms. A theoretical model is presented to determine optimal currents in conductors used for the transportation. We experimentally demonstrate a fast adiabatic transportation of Rubidium ( 87 Rb) cold atoms with minimal loss and heating with as few as three conveyor belt conductors. This novel design of a multilayered conveyor belt structure is fabricated in aluminium nitride (AlN) because of its outstanding thermal and electrical properties. This demonstration would pave a way for a compact and portable quantum device required for quantum information processing and sensors, where precise positioning of cold atoms is desirable.

  2. The effects of seat belt legislation on road traffic injuries.

    Science.gov (United States)

    Trinca, G W; Dooley, B J

    1977-04-01

    The compulsory wearing of seat belts, first introduced in the world in Victoria in 1970, has effectively reduced the number of deaths and injuries by approximately one-third for car occupants involved in motor vehicle crashes. Initially, the legislation did not apply to children under the age of eight years, but in 1975 a further law was introduced banning children from the front seat of any vehicle unless properly harnessed. Seat belts offer the best protection for front seat drivers and passengers involved in frontal impacts, but offer less protection to the recipient of a side impact. Ten per cent of car occupants admitted to hospital after a frontal impact show injuries, mostly minor, directly attibutable to the wearing of seat belts.

  3. Radiation belt seed population and its association with the relativistic electron dynamics: A statistical study: Radiation Belt Seed Population

    International Nuclear Information System (INIS)

    Tang, C. L.; Wang, Y. X.; Ni, B.; Zhang, J.-C.

    2017-01-01

    Using the Van Allen Probes data, we study the radiation belt seed population and it associated with the relativistic electron dynamics during 74 geomagnetic storm events. Based on the flux changes of 1 MeV electrons before and after the storm peak, these storm events are divided into two groups of “non-preconditioned” and “preconditioned”. The statistical study shows that the storm intensity is of significant importance for the distribution of the seed population (336 keV electrons) in the outer radiation belt. However, substorm intensity can also be important to the evolution of the seed population for some geomagnetic storm events. For non-preconditioned storm events, the correlation between the peak fluxes and their L-shell locations of the seed population and relativistic electrons (592 keV, 1.0 MeV, 1.8 MeV, and 2.1 MeV) is consistent with the energy-dependent dynamic processes in the outer radiation belt. For preconditioned storm events, the correlation between the features of the seed population and relativistic electrons is not fully consistent with the energy-dependent processes. It is suggested that the good correlation between the radiation belt seed population and ≤1.0 MeV electrons contributes to the prediction of the evolution of ≤1.0 MeV electrons in the Earth’s outer radiation belt during periods of geomagnetic storms.

  4. Sulfur and lead isotope geochemistry of the orogenic gold deposits in the eastern Kunlun area, Qinghai province

    International Nuclear Information System (INIS)

    Feng Chengyou; Zhang Dequan; Li Daxin; She Hongquan; Zhu Huaping

    2003-01-01

    Based on researches on the basic geological characteristics and sulfur and lead isotopic geochemistry of four typical gold deposits, it is considered that they have many similar geo-geochemical characteristics and are all related genetically to orogenic process. Therefore, they should belong to a type of orogenic gold deposits according to the newest classification of gold deposits provided by Kerrich et al. (2000). There is a big change in the average 34 S values of the sulfides selected from different deposits, varying from -3.7‰-4.4‰ and tower-shape distribution is apparent. The lead isotope in four gold deposits is characterized by high compositions and minor changes, with 206 Pb/ 204 Pb > 18.3380, 207 Pb/ 204 Pb > 15.5555, 208 Pb/ 204 Pb >38.1796 in ores and wall-rocks, it can be concluded that the ore-forming material consisting of sulfur and lead are mainly derived from wall-rocks. Intensive subduction and collision during late Paleozoic and early Mesozoic not only formed deep faults, large-scale shear belt, and low-order folds and faults but also induced fluidization and mineralization, and resulted in formation and zonal distribution of several large or medium gold deposits in this area. (authors)

  5. The Belt voice: Acoustical measurements and esthetic correlates

    Science.gov (United States)

    Bounous, Barry Urban

    This dissertation explores the esthetic attributes of the Belt voice through spectral acoustical analysis. The process of understanding the nature and safe practice of Belt is just beginning, whereas the understanding of classical singing is well established. The unique nature of the Belt sound provides difficulties for voice teachers attempting to evaluate the quality and appropriateness of a particular sound or performance. This study attempts to provide answers to the question "does Belt conform to a set of measurable esthetic standards?" In answering this question, this paper expands on a previous study of the esthetic attributes of the classical baritone voice (see "Vocal Beauty", NATS Journal 51,1) which also drew some tentative conclusions about the Belt voice but which had an inadequate sample pool of subjects from which to draw. Further, this study demonstrates that it is possible to scientifically investigate the realm of musical esthetics in the singing voice. It is possible to go beyond the "a trained voice compared to an untrained voice" paradigm when evaluating quantitative vocal parameters and actually investigate what truly beautiful voices do. There are functions of sound energy (measured in dB) transference which may affect the nervous system in predictable ways and which can be measured and associated with esthetics. This study does not show consistency in measurements for absolute beauty (taste) even among belt teachers and researchers but does show some markers with varying degrees of importance which may point to a difference between our cognitive learned response to singing and our emotional, more visceral response to sounds. The markers which are significant in determining vocal beauty are: (1) Vibrancy-Characteristics of vibrato including speed, width, and consistency (low variability). (2) Spectral makeup-Ratio of partial strength above the fundamental to the fundamental. (3) Activity of the voice-The quantity of energy being produced. (4

  6. An Experimental Concept for Probing Nonlinear Physics in Radiation Belts

    Science.gov (United States)

    Crabtree, C. E.; Ganguli, G.; Tejero, E. M.; Amatucci, B.; Siefring, C. L.

    2017-12-01

    A sounding rocket experiment, Space Measurement of Rocket-Released Turbulence (SMART), can be used to probe the nonlinear response to a known stimulus injected into the radiation belt. Release of high-speed neutral barium atoms (8- 10 km/s) generated by a shaped charge explosion in the ionosphere can be used as the source of free energy to seed weak turbulence in the ionosphere. The Ba atoms are photo-ionized forming a ring velocity distribution of heavy Ba+ that is known to generate lower hybrid waves. Induced nonlinear scattering will convert the lower hybrid waves into EM whistler/magnetosonic waves. The escape of the whistlers from the ionospheric region into the radiation belts has been studied and their observable signatures quantified. The novelty of the SMART experiment is to make coordinated measurement of the cause and effect of the turbulence in space plasmas and from that to deduce the role of nonlinear scattering in the radiation belts. Sounding rocket will carry a Ba release module and an instrumented daughter section that includes vector wave magnetic and electric field sensors, Langmuir probes and energetic particle detectors. The goal of these measurements is to determine the whistler and lower hybrid wave amplitudes and spectrum in the ionospheric source region and look for precipitated particles. The Ba release may occur at 600-700 km near apogee. Ground based cameras and radio diagnostics can be used to characterize the Ba and Ba+ release. The Van Allen Probes can be used to detect the propagation of the scattering-generated whistler waves and their effects in the radiation belts. By detecting whistlers and measuring their energy density in the radiation belts the SMART mission will confirm the nonlinear generation of whistlers through scattering of lower hybrid along with other nonlinear responses of the radiation belts and their connection to weak turbulence.

  7. High-energy outer radiation belt dynamic modeling

    International Nuclear Information System (INIS)

    Chiu, Y.T.; Nightingale, R.W.; Rinaldi, M.A.

    1989-01-01

    Specification of the average high-energy radiation belt environment in terms of phenomenological montages of satellite measurements has been available for some time. However, for many reasons both scientific and applicational (including concerns for a better understanding of the high-energy radiatino background in space), it is desirable to model the dynamic response of the high-energy radiation belts to sources, to losses, and to geomagnetic activity. Indeed, in the outer electron belt, this is the only mode of modeling that can handle the large intensity fluctuations. Anticipating the dynamic modeling objective of the upcoming Combined Release and Radiation Effects Satellite (CRRES) program, we have undertaken to initiate the study of the various essential elements in constructing a dynamic radiation belt model based on interpretation of satellite data according to simultaneous radial and pitch-angle diffusion theory. In order to prepare for the dynamic radiation belt modeling based on a large data set spanning a relatively large segment of L-values, such as required for CRRES, it is important to study a number of test cases with data of similar characteristics but more restricted in space-time coverage. In this way, models of increasing comprehensiveness can be built up from the experience of elucidating the dynamics of more restrictive data sets. The principal objectives of this paper are to discuss issues concerning dynamic modeling in general and to summarize in particular the good results of an initial attempt at constructing the dynamics of the outer electron radiation belt based on a moderately active data period from Lockheed's SC-3 instrument flown on board the SCATHA (P78-2) spacecraft. Further, we shall discuss the issues brought out and lessons learned in this test case

  8. Cripple Creek and other alkaline-related gold deposits in the Southern Rocky Mountains, USA: Influence of regional tectonics

    Science.gov (United States)

    Kelley, K.D.; Ludington, S.

    2002-01-01

    Alkaline-related epithermal vein, breccia, disseminated, skarn, and porphyry gold deposits form a belt in the southern Rocky Mountains along the eastern edge of the North American Cordillera. Alkaline igneous rocks and associated hydrothermal deposits formed at two times. The first was during the Laramide orogeny (about 70-40 Ma), with deposits restricted spatially to the Colorado mineral belt (CMB). Other alkaline igneous rocks and associated gold deposits formed later, during the transition from a compressional to an extensional regime (about 35-27 Ma). These younger rocks and associated deposits are more widespread, following the Rocky Mountain front southward, from Cripple Creek in Colorado through New Mexico. All of these deposits are on the eastern margin of the Cordillera, with voluminous calc-alkaline rocks to the west. The largest deposits in the belt include Cripple Creek and those in the CMB. The most important factor in the formation of all of the gold deposits was the near-surface emplacement of relatively oxidized volatile-rich alkaline magmas. Strontium and lead isotope compositions suggest that the source of the magmas was subduction-modified subcontinental lithosphere. However, Cripple Creek alkaline rocks and older Laramide alkaline rocks in the CMB that were emplaced through hydrously altered LREE-enriched rocks of the Colorado (Yavapai) province have 208Pb/204Pb ratios that suggest these magmas assimilated and mixed with significant amounts of lower crust. The anomalously hot, thick, and light crust beneath Colorado may have been a catalyst for large-scale transfer of volatiles and crustal melting. Increased dissolved H2O (and CO2, F, Cl) of these magmas may have resulted in more productive gold deposits due to more efficient magmatic-hydrothermal systems. High volatile contents may also have promoted Te and V enrichment, explaining the presence of fluorite, roscoelite (vanadium-rich mica) and tellurides in the CMB deposits and Cripple Creek as

  9. COMPREHENSIVE CHECK MEASUREMENT OF KEY PARAMETERS ON MODEL BELT CONVEYOR

    Directory of Open Access Journals (Sweden)

    Vlastimil MONI

    2013-07-01

    Full Text Available Complex measurements of characteristic parameters realised on a long distance model belt conveyor are described. The main objective was to complete and combine the regular measurements of electric power on drives of belt conveyors operated in Czech opencast mines with measurements of other physical quantities and to gain by this way an image of their mutual relations and relations of quantities derived from them. The paper includes a short description and results of the measurements on an experimental model conveyor with a closed material transport way.

  10. ALT-II toroidal belt limiter biasing experiments on TEXTOR

    International Nuclear Information System (INIS)

    Doerner, R.; Boedo, J.A.; Gray, D.S.

    1991-01-01

    Edge electric fields have been related to H-mode-like behaviour. The experiments reported here are an attempt to control the SOL profiles by electrostatic biasing of the full toroidal-belt limiter ALT-II. The specific goals are: influencing the edge particle flows, particle removal, power deposition and the global confinement. The ALT-II pump limiter is a full toroidal belt located at 45 o below the outer midplane and consisting of eight graphite covered blades which can be independently biased. Particle scoops located behind the limiter neutralize and direct the incoming plasma into the pumping ducts. (author) 5 refs., 3 figs

  11. Type QH-200 conveyor-belt nuclear scale

    International Nuclear Information System (INIS)

    Li Shuming; Dong Shiyuan; Li Furong; Wan Zemin

    1991-01-01

    Type QH-200 conveyor-belt nuclear scale is a reliable and on-line device that weighs solids mass flow continuously by γ-ray absorption and scattering. The operation principle and measuring method are described. And some factors influencing the accuracy are discussed. The full scale total weight of type QH-200 nuclear scale is 10 6 t. The result of calibration in the industrial field shows that the accuracy of QH-200 is better than ±1.0% for typical belt loading

  12. Surface vertical deposition for gold nanoparticle film

    International Nuclear Information System (INIS)

    Diao, J J; Qiu, F S; Chen, G D; Reeves, M E

    2003-01-01

    In this rapid communication, we present the surface vertical deposition (SVD) method to synthesize the gold nanoparticle films. Under conditions where the surface of the gold nanoparticle suspension descends slowly by evaporation, the gold nanoparticles in the solid-liquid-gas junction of the suspension aggregate together on the substrate by the force of solid and liquid interface. When the surface properties of the substrate and colloidal nanoparticle suspension define for the SVD, the density of gold nanoparticles in the thin film made by SVD only depends on the descending velocity of the suspension surface and on the concentration of the gold nanoparticle suspension. (rapid communication)

  13. [Biosynthesis of gold nanoparticles by Azospirillum brasilense].

    Science.gov (United States)

    Kupriashina, M A; Vetchinkina, E P; Burov, A M; Ponomareva, E G; Nikitina, V E

    2014-01-01

    Plant-associated nitrogen-fixing soil bacteria Azospirillum brasilense were shown to reduce the gold of chloroauric acid to elemental gold, resulting in formation of gold nanoparicles. Extracellular phenoloxidizing enzymes (laccases and Mn peroxidases) were shown to participate in reduction of Au+3 (HAuCl4) to Au(0). Transmission electron microscopy revealed accumulation of colloidal gold nanoparticles of diverse shape in the culture liquid of A. brasilense strains Sp245 and Sp7. The size of the electron-dense nanospheres was 5 to 50 nm, and the size of nanoprisms varied from 5 to 300 nm. The tentative mechanism responsible for formation of gold nanoparticles is discussed.

  14. Nature and source of the ore-forming fluids associated with orogenic gold deposits in the Dharwar Craton

    Directory of Open Access Journals (Sweden)

    Biswajit Mishra

    2018-05-01

    Full Text Available Neoarchean orogenic gold deposits, associated with the greenstone-granite milieus in the Dharwar Craton include (1 the famous Kolar mine and the world class Hutti deposit; (2 small mines at Hira-Buddini, Uti, Ajjanahalli, and Guddadarangavanahalli; (3 prospects at Jonnagiri; and (4 old mining camps in the Gadag and Ramagiri-Penakacherla belts. The existing diametric views on the source of ore fluid for formation of these deposits include fluids exsolved from granitic melts and extracted by metamorphic devolatilization of the greenstone sequences. Lode gold mineralization occurs in structurally controlled higher order splays in variety of host rocks such as mafic/felsic greenstones, banded iron formations, volcaniclastic rocks and granitoids. Estimated metamorphic conditions of the greenstones vary from lower greenschist facies to mid-amphibolite facies and mineralizations in all the camps are associated with distinct hydrothermal alterations. Fluid inclusion microthermometric and Raman spectroscopic studies document low salinity aqueous-gaseous (H2O + CO2 ± CH4 + NaCl ore fluids, which precipitated gold and altered the host rocks in a narrow P–T window of 0.7–2.5 kbar and 215–320 °C. While the calculated fluid O- and C-isotopic values are ambiguous, S-isotopic compositions of pyrite-precipitating fluid show distinct craton-scale uniformity in terms of its reduced nature and a suggested crustal sulfur source.Available ages on greenstone metamorphism, granitoid plutonism and mineralization in the Hutti Belt are tantamount, making a geochronology-based resolution of the existing debate on the metamorphic vs. magmatic fluid source impossible. In contrast, tourmaline geochemistry suggests involvement of single fluid in formation of gold mineralization, primarily derived by metamorphic devolatilization of mafic greenstones and interlayered sedimentary rocks, with minor magmatic contributions. Similarly, compositions of scheelite

  15. Gold and not so real gold in Medieval treatises

    Directory of Open Access Journals (Sweden)

    Srebrenka Bogovic-Zeskoski

    2015-01-01

    Full Text Available The aim of this study is to evidence diverse materials and processes used by artisans (and alchemists required to synthesize a visually viable replacement for gold. The emphasis of the research is upon the production of mosaic gold or porporina, a pigment that has survived into modern times, which was used as ink and as paint. Base metals, mostly tin, but also alloys were used both into foils coated with glazes and varnishes and as pigment. The research focuses upon recipes documented in treatises dating from Antiquity to the late Medieval period (ca. 1500 and an attempt is made to answer two questions. In the first place, why was there a need for a surrogate? Secondly, why are there so few tangible examples detected on surviving artifacts? In conclusion, an argument is offered pointing out that, although much can be learned by scientific examination of artifacts, textual analysis is equally important and necessary to unravel mysteries of ancient technologies

  16. Realization methodology for optimal design of steel structures conveyors with hanging belt

    Directory of Open Access Journals (Sweden)

    Boslovyak P.V.

    2016-03-01

    Full Text Available Presents the results of optimum design of metal structures of the fixed conveyor with hanging belt. The analysis results optimum design of steel structures of stationary conveyor with hanging belt.

  17. Nanotoxicity of gold and gold-cobalt nanoalloy.

    Science.gov (United States)

    Girgis, E; Khalil, W K B; Emam, A N; Mohamed, M B; Rao, K V

    2012-05-21

    Nanotoxicology test of gold nanoparticles (Au NPs) and gold-cobalt (Au-Co) nanoalloy is an important step in their safety evaluation for biomedical applications. The Au and Au-Co NPs were prepared by reducing the metal ions using sodium borohydride (NaBH(4)) in the presence of polyvinyl pyrrolidone (PVP) as a capping material. The average size and shape of the nanoparticles (NPs) were characterized using high resolution transmission electron microscopy (HRTEM). Cobalt presence in the nanoalloy was confirmed by energy dispersive X-ray spectroscopy (EDX) analysis, and the magnetic properties of these particles were determined using a vibrating sample magnetometer (VSM). The Gold and gold-cobalt NPs of average size 15 ± 1.5 nm were administered orally to mice with a dose of 80, 160, and 320 mg/kg per body weight (bw) using gavages. Samples were collected after 7 and 14 days of the treatment. The results indicated that the Au-Co NPs were able to induce significant alteration in the tumor-initiating genes associated with an increase of micronuclei (MNs) formation and generation of DNA adduct (8-hydroxy-2-deoxyguanosine, 8-OHdG) as well as a reduction in the glutathione peroxidase activity. This action of Au-Co NPs was observed using 160 and 320 mg/kg bw at both time intervals. However, Au NPs had much lower effects than Au-Co NPs on alteration in the tumor-initiating genes, frequency of MNs, and generation of 8-OHdG as well as glutathione peroxidase activity except with the highest dose of Au NPs. This study suggests that the potential to cause in vivo genetic and antioxidant enzyme alterations due to the treatment by Au-Co nanoalloy may be attributed to the increase in oxidative stress in mice.

  18. The development of an electronic system to continually monitor, indicate and control, 'belt slippage' in industrial friction 'V' belt drive transmission systems

    International Nuclear Information System (INIS)

    Brown, R E

    2012-01-01

    Belts have been used for centuries as a mechanism to transfer power from some form of drive system to a variety of load systems. Within industry today, many designs of belts but particularly friction, trapezoidal shaped 'V' belts are used and generally transfer power generated by electrical motors to numerous forms of driven load systems. It is suggested that belt systems, through their simplicity are sadly neglected by maintenance functions and generally are left unattended until high degrees of 'belt slippage' through loss of friction or 'belt breakage' provokes maintenance attention. These circumstances are most often identified through the reduced or loss of manufacturing production or the occurrence of catastrophic circumstances such as fire caused through excessive friction/ high belt slippage conditions. Obviously, these situations incur financial losses to companies and in some cases the near loss of the company's main manufacturing plant. Consequently, a satisfactory, viable solution is currently sought by industry to improve on current labour intensive maintenance practices. This paper will present an account of the development of an industrially robust, accurate and repeatable electronic system which continually monitors and indicates the degree of 'slippage' in a 'V' belt drive transmission system and in the circumstance of belt breakage or high belt slippage will enable and control the switching off the drive motor.

  19. Effectiveness of media and enforcement campaigns in increasing seat belt usage rates in a state with a secondary seat belt law.

    Science.gov (United States)

    Vasudevan, Vinod; Nambisan, Shashi S; Singh, Ashok K; Pearl, Traci

    2009-08-01

    In 2005, in terms of seat belt usage rates, Nevada ranked third nationally and first among states with secondary seat belt use enforcement laws in the United States. An effective combination of a media-based education and enforcement campaign helped in this regard. The objective of this article is to document the effectiveness of enforcement and media-based education and outreach campaigns on the seat belt usage rates in Nevada, a state with a secondary seat belt usage law. Observational data on seat belt usage and passenger fatality data are used to evaluate the effectiveness of enforcement campaigns and media-based education and outreach campaigns. Data based on observations of about 40,000 vehicles in each of the years 2003 to 2005 were analyzed. Statistical analyses show that a significant increase in seat belt usage rates among both drivers and passengers for both genders resulted from the accompanying the media and enforcement campaigns. The results from this study indicate that effective and well-planned media/enforcement campaigns can have a significant impact on seat belt usage rates even in a state where the enforcement of seat belt laws can only be as a secondary violation. They validate and expand on findings from other efforts documented in the literature. These results demonstrate that, if coordinated properly, media and enforcement campaigns work very effectively in increasing seat belt usage rates even in states with secondary seat belt laws.

  20. Gold, iron and manganese in central Amapá, Brazil

    Directory of Open Access Journals (Sweden)

    Wilson Scarpelli

    Full Text Available ABSTRACT: Greenstone belts with deposits of gold, iron and manganese are common in the Paleoproterozoic Maroni-Itacaiunas Tectonic Province of the Guiana Shield. In Brazil, in the State of Amapá and northwest of Pará, they are represented by the Vila Nova Group, constituted by a basal unit of metabasalts, covered by metasediments of clastic and chemical origin. The basal metasediments, the Serra do Navio Formation, are made of a cyclothem with lenses of manganese marbles at the top of each cycle. Under the intense weathering of the Amazon, these lenses were oxidized to large deposits of high-grade manganese oxides. The exploitation of these oxides left behind the manganese carbonates and low-grade oxides. The overlaying Serra da Canga Formation presents a calcium and magnesium domain grading to an iron domain with banded silicate and oxide iron formations, mined for iron ores. Overlapping structures and superposed metamorphic crystallizations indicate two phases of dynamothermal metamorphism, the first one with axis to north-northeast and the second one to northwest, with an intermediate phase of thermal metamorphism related to syntectonic granitic intrusions. Shears oriented north-south, possibly formed during the first dynamothermal metamorphism and reactivated in the second, are ideal sites for hydrothermalism and gold mineralization, which is greater when occurs in iron formation and carbonate-bearing rocks, as it happened at the Tucano mine. Layered mafic-ultramafic intrusions in the greenstones represent a potential for chromite and platinum group elements. Pegmatites are source of cassiterite and tantalite exploited from alluvial deposits.

  1. Distribution and composition of gold in porphyry gold systems: example from the Biely Vrch deposit, Slovakia

    Science.gov (United States)

    Koděra, Peter; Kozák, Jaroslav; Brčeková, Jana; Chovan, Martin; Lexa, Jaroslav; Jánošík, Michal; Biroň, Adrián; Uhlík, Peter; Bakos, František

    2018-03-01

    The Biely Vrch deposit in the Western Carpathians is assigned to the shallow, sulfide-poor porphyry gold deposit type and has an exceptionally low Cu/Au ratio. According to 3-D geochemical models, there is a limited spatial correlation between Au and Cu due to the primary introduction of gold by a salt melt and Cu by low-density vapor. Despite a rough spatial correlation of gold grades with quartz stockwork intensity, gold is hosted mostly by altered rock, exclusively in native form. Three main gold mineral assemblages were recognized here. In the deepest parts of the system, the K- and Ca-Na silicate gold assemblage is associated with minerals of high-temperature alteration (plagioclase, K-feldspar, actinolite), with gold grades and fineness depending on depth and potassium content of the host rock: K-silicate alteration hosts the lowest fineness gold ( 914), whereas Ca-Na silicate alteration has the highest ( 983). The intermediate argillic gold assemblage is the most widespread, with gold hosted mainly by chlorite, illite, smectite, and interstratified illite-chlorite-smectite minerals. The gold fineness is mostly variable (875-990) and inherited from the former gold mineral assemblages. The latest advanced argillic gold assemblage has its gold mostly in kaolinite. The extremely high fineness ( 994) results from gold remobilization by late-stage aqueous magmatic-hydrothermal fluids. Uncommon bonanza-grade appears where the earlier gold mineral assemblages were further enriched by this remobilized gold. Primary precipitation of gold occurred during ascent and cooling of salt melts at 450 to 309 °C, mostly during retrograde quartz solubility.

  2. Byzantine gold coins and jewellery

    International Nuclear Information System (INIS)

    Oddy, A.; La Niece, S.

    1986-01-01

    The article deals with the dating of Byzantine gold coinage. The results of such a study are of fundamental importance for the study of the economic history of the later Byzantine Empire and they are also of importance for the historian of technology when studying the composition of the contemporary Byzantine jewellery. Although Carbon-14 dating cannot be used as a method af dating, historians can still benefit from the analysis of the alloy of which the antiquity is made, as this is sometimes characteristic of the period in which it was used. A number of pieces of Byzantine jewellery has been analysed by x-ray fluorescence analysis, after first gently abrading a small area of the surface of the gold with the carborundum paper in an inconspicious position on the back or side of the object. A table is given on the results of this analysis

  3. Reverse Transfection Using Gold Nanoparticles

    Science.gov (United States)

    Yamada, Shigeru; Fujita, Satoshi; Uchimura, Eiichiro; Miyake, Masato; Miyake, Jun

    Reverse transfection from a solid surface has the potential to deliver genes into various types of cell and tissue more effectively than conventional methods of transfection. We present a method for reverse transfection using a gold colloid (GC) as a nanoscaffold by generating nanoclusters of the DNA/reagentcomplex on a glass surface, which could then be used for the regulation of the particle size of the complex and delivery of DNA into nuclei. With this method, we have found that the conjugation of gold nanoparticles (20 nm in particle size) to the pEGFP-N1/Jet-PEI complex resulted in an increase in the intensity of fluorescence of enhanced green fluorescent protein (EGFP) (based on the efficiency of transfection) from human mesenchymal stem cells (hMSCs), as compared with the control without GC. In this manner, we constructed a method for reverse transfection using GC to deliver genes into the cells effectively.

  4. CMS Industries awarded gold, crystal

    CERN Multimedia

    2006-01-01

    The CMS collaboration honoured 10 of its top suppliers in the seventh annual awards ceremony The representatives of the firms that recieved the CMS Gold and Crystal Awards stand with their awards after the ceremony. The seventh annual CMS Awards ceremony was held on Monday 13 March to recognize the industries that have made substantial contributions to the construction of the collaboration's detector. Nine international firms received Gold Awards, and General Tecnica of Italy received the prestigious Crystal Award. Representatives from the companies attended the ceremony during the plenary session of CMS week. 'The role of CERN, its machines and experiments, beyond particle physics is to push the development of equipment technologies related to high-energy physics,'said CMS Awards Coordinator Domenico Campi. 'All of these industries must go beyond the technologies that are currently available.' Without the involvement of good companies over the years, the construction of the CMS detector wouldn't be possible...

  5. Nanobubble trouble on gold surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Kuhle, A.; Garnaes, J.

    2003-01-01

    When analyzing surfaces related to biosensors with in situ atomic force microscopy (AFM), the existence of nanobubbles called for our attention. The bubbles seem to form spontaneously when gold surfaces are immersed in clean water and are probably a general phenomenon at water-solid interfaces....... Besides from giving rise to undesired effects in, for example, biosensors, nanobubbles can also cause artifacts in AFM imaging. We have observed nanobubbles on unmodified gold surfaces, immersed in clean water, using standard silicon AFM probes. Nanobubbles can be made to disappear from contact mode AFM...... images and then to reappear by changing the scanning force. By combining contact mode AFM imaging and local force measurements, the interaction between the nanobubbles and the probe can be analyzed and give information about the characteristics of nanobubbles. A model of the forces between the AFM probe...

  6. 30 CFR 14.22 - Test for flame resistance of conveyor belts.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Test for flame resistance of conveyor belts. 14..., EVALUATION, AND APPROVAL OF MINING PRODUCTS REQUIREMENTS FOR THE APPROVAL OF FLAME-RESISTANT CONVEYOR BELTS Technical Requirements § 14.22 Test for flame resistance of conveyor belts. (a) Test procedures. The test...

  7. PROPOSALS ON IMPROVING THE EXCAVATION, TRANSPORT AND COAL DEPOSIT, USING THE RUBBER CONVEYOR BELT

    Directory of Open Access Journals (Sweden)

    Nicoleta-Maria MIHUT

    2016-05-01

    Full Text Available In this work we make a study of the improvement methods of quantity of material transported by conveyor belt. Determination of discharge of solids entail establish of the parameters of the conveyor belt. As a result, we determine the belt speed who provide maximum discharge of solids materials.

  8. Overland conveyors. Cable or trough belt for 100 km transport haulage

    Energy Technology Data Exchange (ETDEWEB)

    Maton, A.E. [Maton Engineering Pty. Ltd., Orange Grove, WA (Australia)

    2009-07-01

    With the advances in belt conveyor technology today systems of 100 kilometres length are increasingly being considered. This article provides a comparison of two concepts for a 100 kilometre system of five 20 kilometre flights based on trough belt and cable belt technology. (orig.)

  9. The use of seat belts and contributing factors : an international comparison.

    NARCIS (Netherlands)

    Mäkinen, T. Wittink, R.D. & Hagenzieker, M.P.

    1991-01-01

    The purpose of this study was to define factors that contribute to the use or non-use of seat belts. Legislation prescribing compulsory seat belt usage is one of the most important factors. Promotion of the use of seat belts without this legislation is very difficult and time-consuming. So far, the

  10. Knowledge, attitude and use of seat belt among commercial drivers in Sokoto Metropolis

    Directory of Open Access Journals (Sweden)

    A O Abiola

    2010-01-01

    Conclusion: This study has identified high level of knowledge, positive attitude and reported use of seat belt. It is recommended that public awareness of the safety benefits of seat belts and strong enforcement are necessary to achieve optimal use of seat belt.

  11. Using naturalistic driving data to identify variables associated with infrequent, occasional, and consistent seat belt use.

    Science.gov (United States)

    Reagan, Ian J; McClafferty, Julie A; Berlin, Sharon P; Hankey, Jonathan M

    2013-01-01

    Seat belt use is one of the most effective countermeasures to reduce traffic fatalities and injuries. The success of efforts to increase use is measured by road side observations and self-report questionnaires. These methods have shortcomings, with the former requiring a binary point estimate and the latter being subjective. The 100-car naturalistic driving study presented a unique opportunity to study seat belt use in that seat belt status was known for every trip each driver made during a 12-month period. Drivers were grouped into infrequent, occasional, or consistent seat belt users based on the frequency of belt use. Analyses were then completed to assess if these groups differed on several measures including personality, demographics, self-reported driving style variables as well as measures from the 100-car study instrumentation suite (average trip speed, trips per day). In addition, detailed analyses of the occasional belt user group were completed to identify factors that were predictive of occasional belt users wearing their belts. The analyses indicated that consistent seat belt users took fewer trips per day, and that increased average trip speed was associated with increased belt use among occasional belt users. The results of this project may help focus messaging efforts to convert occasional and inconsistent seat belt users to consistent users. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. The status of isotopic investigations of the Limpopo mobile belt

    International Nuclear Information System (INIS)

    Barton, J.M. Jr.

    1981-01-01

    The Limpopo Belt is a zone of multiple deformed metamorphic rocks situated between the Rhodesian and Kaapvaal Cratons of Southern Africa. During the duration of the International Geodynamics Project, geochronologic and isotopic investigations were undertaken in the nothern Transvaal of rocks of the Central Zone, Southern Marginal Zone and Soutpansberg Supergroup. Strontium 86, strontium 87 and lead isotopes were used in the isotopic investigations

  13. Patchy charnockites from Jenapore, Eastern Ghats granulite belt, India

    Indian Academy of Sciences (India)

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

    ∗Present address: Department of Geology, J. K. College, Purulia 723 101, West Bengal, India. The charnockite ... tor of the Eastern Ghats granulite belt, are disposed in a linear fashion and generally have sharp ... Subse- quently, many workers suggested that the 'patchy ..... bly represent two different frozen-in conditions, as.

  14. Determination of Flutter Derivatives for the Great Belt Bridge

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad; Damsgaard, Aage; Reinhold, Thim A.

    1992-01-01

    A new method which combines control theory and system identification techniques has been used to extract flutter derivatives from section model tests for the Great Belt East Bridge. Tests were conducted by exciting the section model simultaneously in vertical and torsional modes of vibration. Tests...

  15. 49 CFR 392.16 - Use of seat belts.

    Science.gov (United States)

    2010-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Driving of Commercial Motor Vehicles § 392.16 Use of seat belts. A commercial motor vehicle which...

  16. Elastic deformation behaviour of Palaeogene clay from Fehmarn Belt area

    DEFF Research Database (Denmark)

    Awadalkarim, Ahmed; Foged, Niels Nielsen; Fabricius, Ida Lykke

    2014-01-01

    Palaeogene clay samples were obtained by high quality boring and sampling techniques (Geobore S-system), during the extensive site investigations for building a bridge in the Fehmarn Belt area to link between Rødbyhavn in Denmark and Puttgarden in Germany. The Palaeogene clay is rich in smectite...

  17. Medical back belt with integrated neuromuscular electrical stimulation

    NARCIS (Netherlands)

    Bottenberg, E. (Eliza); Brinks, G.J. (Ger); Hesse, J. (Jenny)

    2014-01-01

    The medical back belt with integrated neuromuscular electrical stimulation is anorthopedic device, which has two main functions. The first function is to stimulate the backmuscles by using a neuromuscular electrical stimulation device that releases regular,electrical impulses. The second function of

  18. Investigation of the preionization in the high voltage belt pinch

    International Nuclear Information System (INIS)

    Protz, R.

    1975-07-01

    The production of plasmas is investigated which are necessary for shock wave experiments. By optimization of a two-stage pre-ionization, an ignition can be initiated down to 0.5 m of Hg deuterium. The plasma is diagnosed with a 90 0 multichannel laser light scattering in the belt-pinch. (GG/LH) [de

  19. Preservation of meandering river channels in uniformly aggrading channel belts

    NARCIS (Netherlands)

    Lageweg, W.I. van de; Schuurman, F.; Cohen, K.M.; Dijk, W.M. van; Shimizu, Y.; Kleinhans, M.G.

    2016-01-01

    Channel belt deposits from meandering river systems commonly display an internal architecture of stacked depositional features with scoured basal contacts due to channel and bedform migration across a range of scales. Recognition and correct interpretation of these bounding surfaces is essential to

  20. Knowledge, attitude and use of seat belt among commercial drivers ...

    African Journals Online (AJOL)

    The effectiveness of seat belt usage in reducing the severity of the sequelae of road traffic accidents is widely known. ... Each correct response to the knowledge questions was scored one mark and wrong response or non-response was ...

  1. A comparison of outer electron radiation belt dropouts during solar ...

    Indian Academy of Sciences (India)

    Utilizing multiple data sources from the year 1997–2007, this study identifies radiation belt electron dropouts which are ultimately triggered when solar wind stream interfaces (SI) arrived at ... Center for Space Research, School for Physical and Chemical Sciences, North–West University, Potchefstroom 2520, South Africa.

  2. 30 CFR 57.4263 - Underground belt conveyors.

    Science.gov (United States)

    2010-07-01

    ....4263 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Firefighting Equipment § 57.4263 Underground belt conveyors. Fire protection shall be...

  3. Design study of flat belt CVT for electric vehicles

    Science.gov (United States)

    Kumm, E. L.

    1980-01-01

    A continuously variable transmission (CVT) was studied, using a novel flat belt pulley arrangement which couples the high speed output shaft of an energy storage flywheel to the drive train of an electric vehicle. A specific CVT arrangement was recommended and its components were selected and sized, based on the design requirements of a 1700 KG vehicle. A design layout was prepared and engineering calculations made of component efficiencies and operating life. The transmission efficiency was calculated to be significantly over 90% with the expected vehicle operation. A design consistent with automotive practice for low future production costs was considered, together with maintainability. The technology advancements required to develop the flat belt CVT were identified and an estimate was made of how the size of the flat belt CVT scales to larger and smaller design output torques. The suitability of the flat belt CVT for alternate application to an electric vehicle powered by an electric motor without flywheel and to a hybrid electric vehicle powered by an electric motor with an internal combustion engine was studied.

  4. Mafic dykes at the southwestern margin of Eastern Ghats belt ...

    Indian Academy of Sciences (India)

    Ghats belt: Evidence of rifting and collision. S Bhattacharya. 1,∗ ... 1.3 Ga, which may have been initiated by intra-plate volcanism. 1. Introduction ... tively, is described as a compressional orogen. Keywords. ... charnockite gneiss, around Naraseraopet, AP (b) Thin mafic ... Sometimes orthopyroxene also occurs at margin of.

  5. The charge transport in an electrostatic belt generator

    NARCIS (Netherlands)

    Vermeer, A.; Strasters, B.A.

    1975-01-01

    The fluctuations in the charge transport system of an EN Tandem Van de Graaff accelerator have been investigated by means of a frequency spectrum analyser. Frequency spectra of the terminal ripple, the short-circuit current and the voltage at the belt charge screen have been measured. Also the

  6. Structural appraisal of the Gadag schist belt from gravity investigations

    Indian Academy of Sciences (India)

    : the high density Gadag schist belt is characterized by a gravity high and occurs in two discontinuous segments — the main N-S trending segment, and its thinner NW-SE trending extension, the two separated by a NE-SW trending deep ...

  7. 1991 National campaign to increase safety belt usage.

    NARCIS (Netherlands)

    National Highway Traffic Safety Administration NHTSA

    1992-01-01

    The central theme of this paper is the national campaign of the USA to be conducted in 1991 and 1992, in order to reach the goal of 70 percent safety belt usage by 1992. Among other things, it is shown that visible enforcement of existing laws offers the greatest potential for achieving this goal.

  8. Asteroid Family Associations of Main-Belt Comets

    Science.gov (United States)

    Hsieh, Henry H.; Novakovic, Bojan; Kim, Yoonyoung; Brasser, Ramon

    2016-10-01

    We present a population-level analysis of the asteroid family associations of known main-belt comets or main-belt comet candidates (which, to date, have largely just been analyzed on individual bases as they have been discovered). In addition to family associations that have already been reported in the literature, we have identified dynamical relationships between 324P/La Sagra and the Alauda family, P/2015 X6 (PANSTARRS) and the Aeolia family, and P/2016 G1 (PANSTARRS) and the Adeona family. We will discuss the overall implications of these family associations, particularly as they pertain to the hypothesis that members of primitive asteroid family members may be more susceptible to producing observable sublimation-driven dust emission activity, and thus becoming main-belt comets. We will also discuss the significance of other dynamical and physical properties of a family or sub-family as they relate to the likelihood of that family containing one or more currently active main-belt comets.

  9. Linking main-belt comets to asteroid families

    Science.gov (United States)

    Novakovic, B.; Hsieh, H. H.; Cellino, A.

    2012-09-01

    Here we present our results obtained by applying different methods in order to establish a firm link between the main-belt comets (MBCs) and colisionally-formed asteroid families (AFs), i.e, to possibly find additional line of evidence supporting the hypothesis that MBCs may be preferentially found among the members of young AFs.

  10. Resolving the planetesimal belt of HR 8799 with ALMA

    Science.gov (United States)

    Booth, Mark; Jordán, Andrés; Casassus, Simon; Hales, Antonio S.; Dent, William R. F.; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

    2016-07-01

    The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fitted by a broad ring between 145^{+12}_{-12} au and 429^{+37}_{-32} au at an inclination of 40^{+5}_{-6}° and a position angle of 51^{+8}_{-8}°. A disc edge at ˜145 au is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orbit of planet b.

  11. Evolution of the Bhandara-Balaghat granulite belt along the ...

    Indian Academy of Sciences (India)

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

    The Bhandara-Balaghat granulite (BBG) belt occurs as a 190km long, detached narrow, ... have undergone an earlier high-grade granulite metamorphism at 2672±54 Ma (Sm-Nd age) and a .... ∼10.5kb pressure and 775◦ C temperature. They.

  12. Gravity inferred subsurface structure of Gadwal schist belt, Andhra ...

    Indian Academy of Sciences (India)

    residual gravity profile data were interpreted using 2-D prism models. The results ... Geological and geophysical layout map of the Gadwal schist belt area, Andhra Pradesh (after Ananda Murty and ... Observed gravity (Bouguer) values, regional, residual and inferred gravity models along traverse I of the Gadwal schist.

  13. Gold, currencies and market efficiency

    Czech Academy of Sciences Publication Activity Database

    Krištoufek, Ladislav; Vošvrda, Miloslav

    2016-01-01

    Roč. 449, č. 1 (2016), s. 27-34 ISSN 0378-4371 R&D Projects: GA ČR(CZ) GBP402/12/G097 Institutional support: RVO:67985556 Keywords : Efficient market hypothesis, * Gold * Currencies, * Fractal dimension * Entropy * Long-Term memory Subject RIV: AH - Economics Impact factor: 2.243, year: 2016 http://library.utia.cas.cz/separaty/2016/E/kristoufek-0455876.pdf

  14. Ground Optical Lightning Detector (GOLD)

    Science.gov (United States)

    Jackson, John, Jr.; Simmons, David

    A photometer developed to characterize lightning from the ground is discussed. The detector and the electronic signal processing and data storage systems are presented along with field data measured by the system. The discussion will include improvements that will be incorporated to enhance the measurement of lightning and the data storage capability to record for many days without human involvement. Finally, the calibration of the GOLD system is presented.

  15. Extinction Coefficient of Gold Nanostars

    OpenAIRE

    de Puig, Helena; Tam, Justina O.; Yen, Chun-Wan; Gehrke, Lee; Hamad-Schifferli, Kimberly

    2015-01-01

    Gold nanostars (NStars) are highly attractive for biological applications due to their surface chemistry, facile synthesis and optical properties. Here, we synthesize NStars in HEPES buffer at different HEPES/Au ratios, producing NStars of different sizes and shapes, and therefore varying optical properties. We measure the extinction coefficient of the synthesized NStars at their maximum surface plasmon resonances (SPR), which range from 5.7 × 108 to 26.8 × 108 M−1cm−1. Measured values correl...

  16. Biomolecular Assembly of Gold Nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Micheel, Christine Marya [Univ. of California, Berkeley, CA (United States)

    2005-05-20

    Over the past ten years, methods have been developed to construct discrete nanostructures using nanocrystals and biomolecules. While these frequently consist of gold nanocrystals and DNA, semiconductor nanocrystals as well as antibodies and enzymes have also been used. One example of discrete nanostructures is dimers of gold nanocrystals linked together with complementary DNA. This type of nanostructure is also known as a nanocrystal molecule. Discrete nanostructures of this kind have a number of potential applications, from highly parallel self-assembly of electronics components and rapid read-out of DNA computations to biological imaging and a variety of bioassays. My research focused in three main areas. The first area, the refinement of electrophoresis as a purification and characterization method, included application of agarose gel electrophoresis to the purification of discrete gold nanocrystal/DNA conjugates and nanocrystal molecules, as well as development of a more detailed understanding of the hydrodynamic behavior of these materials in gels. The second area, the development of methods for quantitative analysis of transmission electron microscope data, used computer programs written to find pair correlations as well as higher order correlations. With these programs, it is possible to reliably locate and measure nanocrystal molecules in TEM images. The final area of research explored the use of DNA ligase in the formation of nanocrystal molecules. Synthesis of dimers of gold particles linked with a single strand of DNA possible through the use of DNA ligase opens the possibility for amplification of nanostructures in a manner similar to polymerase chain reaction. These three areas are discussed in the context of the work in the Alivisatos group, as well as the field as a whole.

  17. Gold Nanocages for Biomedical Applications**

    OpenAIRE

    Skrabalak, Sara E.; Chen, Jingyi; Au, Leslie; Lu, Xianmao; Li, Xingde; Xia, Younan

    2007-01-01

    Nanostructured materials provide a promising platform for early cancer detection and treatment. Here we highlight recent advances in the synthesis and use of Au nanocages for such biomedical applications. Gold nanocages represent a novel class of nanostructures, which can be prepared via a remarkably simple route based on the galvanic replacement reaction between Ag nanocubes and HAuCl4. The Au nanocages have a tunable surface plasmon resonance peak that extends into the near-infrared, where ...

  18. Does unbelted safety requirement affect protection for belted occupants?

    Science.gov (United States)

    Hu, Jingwen; Klinich, Kathleen D; Manary, Miriam A; Flannagan, Carol A C; Narayanaswamy, Prabha; Reed, Matthew P; Andreen, Margaret; Neal, Mark; Lin, Chin-Hsu

    2017-05-29

    Federal regulations in the United States require vehicles to meet occupant performance requirements with unbelted test dummies. Removing the test requirements with unbelted occupants might encourage the deployment of seat belt interlocks and allow restraint optimization to focus on belted occupants. The objective of this study is to compare the performance of restraint systems optimized for belted-only occupants with those optimized for both belted and unbelted occupants using computer simulations and field crash data analyses. In this study, 2 validated finite element (FE) vehicle/occupant models (a midsize sedan and a midsize SUV) were selected. Restraint design optimizations under standardized crash conditions (U.S.-NCAP and FMVSS 208) with and without unbelted requirements were conducted using Hybrid III (HIII) small female and midsize male anthropomorphic test devices (ATDs) in both vehicles on both driver and right front passenger positions. A total of 10 to 12 design parameters were varied in each optimization using a combination of response surface method (RSM) and genetic algorithm. To evaluate the field performance of restraints optimized with and without unbelted requirements, 55 frontal crash conditions covering a greater variety of crash types than those in the standardized crashes were selected. A total of 1,760 FE simulations were conducted for the field performance evaluation. Frontal crashes in the NASS-CDS database from 2002 to 2012 were used to develop injury risk curves and to provide the baseline performance of current restraint system and estimate the injury risk change by removing the unbelted requirement. Unbelted requirements do not affect the optimal seat belt and airbag design parameters in 3 out of 4 vehicle/occupant position conditions, except for the SUV passenger side. Overall, compared to the optimal designs with unbelted requirements, optimal designs without unbelted requirements generated the same or lower total injury risks for

  19. Jabiluka gold-uranium project

    International Nuclear Information System (INIS)

    1988-01-01

    The Jabiluka gold-uranium deposit, 230km east of Darwin in the Alligator Rivers Region of the Northern Territory, was discovered by Pancontinental Mining Limited in 1971. Jabiluka, with reserves in excess of 200,000 tonnes of contained U 3 O 8 in two deposits 500 metres apart, is the world's largest high grade uranium deposit and also contains nearly 12 tonnes of gold. It is proposed that only the larger deposit, Jabiluka II will be mined - by underground extraction methods, and that 275,000 tonnes of ore per year will be mined and processed to produce 1,500 tonnes of U 3 O 8 and up to 30,000 oz of gold. The revenue from the uranium sales is estimated to be of the order of A$100 million per year at A$30/lb. By the end of 1982 all necessary mining and environmental approvals had been obtained and significant marketing progress made. With the Australian Labor Party winning Commonwealth Government in the 1983 election, Pancontinental's permission to seek sales contracts was withdrawn and development of the Jabiluka deposit ceased. Jabiluka remains undeveloped - awaiting a change in Australian Government policy on uranium. figs., maps

  20. Analysis of gold and silver concentration on gold mining tailings by neutron activation analysis

    International Nuclear Information System (INIS)

    Sadikov, I.I.; Salimov, M.I.; Sadykova, Z.O.

    2014-01-01

    Full text: Instrumental neutron-activation analysis without radiochemical separation is one of most applicable and often used methods to analyze the concentration of gold, silver and other rare and noble metals in gold ores. This method is not suitable for analyzing low concentration of gold and silver in gold mining tailings due to rather high concentration of some elements. Samples are dissolved by boiling in a mixture of concentrated hydrochloric and nitric acids to extract gold and silver into the solution. Chemical yield of gold and silver after dissolution of the sample and further chromatographic separation is between 92 and 95 percent respectively

  1. Quantitative Simulation of QARBM Challenge Events During Radiation Belt Enhancements

    Science.gov (United States)

    Li, W.; Ma, Q.; Thorne, R. M.; Bortnik, J.; Chu, X.

    2017-12-01

    Various physical processes are known to affect energetic electron dynamics in the Earth's radiation belts, but their quantitative effects at different times and locations in space need further investigation. This presentation focuses on discussing the quantitative roles of various physical processes that affect Earth's radiation belt electron dynamics during radiation belt enhancement challenge events (storm-time vs. non-storm-time) selected by the GEM Quantitative Assessment of Radiation Belt Modeling (QARBM) focus group. We construct realistic global distributions of whistler-mode chorus waves, adopt various versions of radial diffusion models (statistical and event-specific), and use the global evolution of other potentially important plasma waves including plasmaspheric hiss, magnetosonic waves, and electromagnetic ion cyclotron waves from all available multi-satellite measurements. These state-of-the-art wave properties and distributions on a global scale are used to calculate diffusion coefficients, that are then adopted as inputs to simulate the dynamical electron evolution using a 3D diffusion simulation during the storm-time and the non-storm-time acceleration events respectively. We explore the similarities and differences in the dominant physical processes that cause radiation belt electron dynamics during the storm-time and non-storm-time acceleration events. The quantitative role of each physical process is determined by comparing against the Van Allen Probes electron observations at different energies, pitch angles, and L-MLT regions. This quantitative comparison further indicates instances when quasilinear theory is sufficient to explain the observed electron dynamics or when nonlinear interaction is required to reproduce the energetic electron evolution observed by the Van Allen Probes.

  2. Radiation Belt Transport Driven by Solar Wind Dynamic Pressure Fluctuations

    Science.gov (United States)

    Kress, B. T.; Hudson, M. K.; Ukhorskiy, A. Y.; Mueller, H.

    2012-12-01

    The creation of the Earth's outer zone radiation belts is attributed to earthward transport and adiabatic acceleration of electrons by drift-resonant interactions with electromagnetic fluctuations in the magnetosphere. Three types of radial transport driven by solar wind dynamic pressure fluctuations that have been identified are: (1) radial diffusion [Falthammer, 1965], (2) significant changes in the phase space density radial profile due to a single or few ULF drift-resonant interactions [Ukhorskiy et al., 2006; Degeling et al., 2008], and (3) shock associated injections of radiation belt electrons occurring in less than a drift period [Li et al., 1993]. A progress report will be given on work to fully characterize different forms of radial transport and their effect on the Earth's radiation belts. The work is being carried out by computing test-particle trajectories in electric and magnetic fields from a simple analytic ULF field model and from global MHD simulations of the magnetosphere. Degeling, A. W., L. G. Ozeke, R. Rankin, I. R. Mann, and K. Kabin (2008), Drift resonant generation of peaked relativistic electron distributions by Pc 5 ULF waves, textit{J. Geophys. Res., 113}, A02208, doi:10.1029/2007JA012411. Fälthammar, C.-G. (1965), Effects of Time-Dependent Electric Fields on Geomagnetically Trapped Radiation, J. Geophys. Res., 70(11), 2503-2516, doi:10.1029/JZ070i011p02503. Li, X., I. Roth, M. Temerin, J. R. Wygant, M. K. Hudson, and J. B. Blake (1993), Simulation of the prompt energization and transport of radiation belt particles during the March 24, 1991 SSC, textit{Geophys. Res. Lett., 20}(22), 2423-2426, doi:10.1029/93GL02701. Ukhorskiy, A. Y., B. J. Anderson, K. Takahashi, and N. A. Tsyganenko (2006), Impact of ULF oscillations in solar wind dynamic pressure on the outer radiation belt electrons, textit{Geophys. Res. Lett., 33}(6), L06111, doi:10.1029/2005GL024380.

  3. Flexible electrode belt for EIT using nanofiber web dry electrodes.

    Science.gov (United States)

    Oh, Tong In; Kim, Tae Eui; Yoon, Sun; Kim, Kap Jin; Woo, Eung Je; Sadleir, Rosalind J

    2012-10-01

    Efficient connection of multiple electrodes to the body for impedance measurement and voltage monitoring applications is of critical importance to measurement quality and practicality. Electrical impedance tomography (EIT) experiments have generally required a cumbersome procedure to attach the multiple electrodes needed in EIT. Once placed, these electrodes must then maintain good contact with the skin during measurements that may last several hours. There is usually also the need to manage the wires that run between the electrodes and the EIT system. These problems become more severe as the number of electrodes increases, and may limit the practicality and portability of this imaging method. There have been several trials describing human-electrode interfaces using configurations such as electrode belts, helmets or rings. In this paper, we describe an electrode belt we developed for long-term EIT monitoring of human lung ventilation. The belt included 16 embossed electrodes that were designed to make good contact with the skin. The electrodes were fabricated using an Ag-plated PVDF nanofiber web and metallic threads. A large contact area and padding were used behind each electrode to improve subject comfort and reduce contact impedances. The electrodes were incorporated, equally spaced, into an elasticated fabric belt. We tested the electrode belt in conjunction with the KHU Mark1 multi-frequency EIT system, and demonstrate time-difference images of phantoms and human subjects during normal breathing and running. We found that the Ag-plated PVDF nanofiber web electrodes were suitable for long-term measurement because of their flexibility and durability. Moreover, the contact impedance and stability of the Ag-plated PVDF nanofiber web electrodes were found to be comparable to similarly tested Ag/AgCl electrodes.

  4. Characterization of gold mineralization in Garin Hawal area, Kebbi State, NW Nigeria, using remote sensing

    Directory of Open Access Journals (Sweden)

    Talaat M. Ramadan

    2010-12-01

    Full Text Available Garin Hawal area, Kebbi State, NW Nigeria is part of the Neoproterozoic to Early Phanerozoic terrane separating the west African and Congo Cratons. Three main gold-bearing shear zones were detected in the study area from the processed Landsat ETM+ images and extensive ground investigation. Field and petrographical studies indicate that the Neoproterozoic rocks are represented by a highly folded and faulted belt constituted of hornblende, muscovite and graphite schist. They are intruded by granondiorites and late to post granitic dykes. Extensive alteration zones were identified using high resolution QuickBird image along Garin Hawal shear zone. The alteration zones and associated quartz veins are generally concordant with the main NE–SW regional structural trend and are dipping to the NW. Geochemical studies indicate that the gold content reaches 8 g/t in the alteration zones, while it reaches up to 35 g/t in the quartz veins. Mineralogical studies indicate that the alterations are strongly potassium-enriched. Pyrophyllite, kaolinite, illite, gypsum and quartz also occur. The main ore minerals are gold, chalcopyrite, arsenopyrite, pyrite, galena and iron oxides. This study indicates that the alteration zones and the associated quartz veins in the muscovite schist are promising and need more detailed exploration for Au and Ag mineralization to evaluate their potential.

  5. Trace element mapping of pyrite from Archean gold deposits – A comparison between PIXE and EPMA

    Energy Technology Data Exchange (ETDEWEB)

    Agangi, A., E-mail: aagangi@uj.ac.za [University of Johannesburg, Department of Geology, Auckland Park 2006 (South Africa); Przybyłowicz, W., E-mail: przybylowicz@tlabs.ac.za [Materials Research Department, iThemba LABS, National Research Foundation, Somerset West 7129 (South Africa); AGH University of Science and Technology, Faculty of Physics & Applied Computer Science, Al. A. Mickiewicza 30, 30-059 Krakow (Poland); Hofmann, A., E-mail: ahofmann@uj.ac.za [University of Johannesburg, Department of Geology, Auckland Park 2006 (South Africa)

    2015-04-01

    Chemical zoning of pyrites can record the evolution of mineralising fluids at widely varying P–T conditions ranging from diagenesis to medium-grade metamorphism. If preserved, zoning can reveal growth textures, brecciation and veining, resorption and recrystallisation events, thus shedding light on the processes that contributed to ore formation. Chemical zoning of sulfides is invisible in optical microscopy, but can be studied by chemical etching, high-contrast back-scattering electron images, and elemental imaging. In this study we compared micro-PIXE and WDS-EPMA elemental maps on the chemically zoned pyrites in mineralised vein-bearing samples from the Sheba and Fairview gold mines in the Barberton Greenstone Belt, South Africa. Elemental images show complex distribution of trace elements, suggesting multiple events of pyrite crystallisation and gold deposition. EPMA maps show fine-scale variations reflecting growth and recrystallisation textures marked, in particular, by variations of As, Ni, and Co. In PIXE maps, gold occurs both as finely-distributed and discrete inclusions, suggesting incorporation in the pyrite structure as solid solution, and deposition as electrum inclusions, respectively. Micro-PIXE and EPMA provide complementary information, forming together a powerful tool to obtain information on chemical zoning of pyrites in ore deposits.

  6. Large enhancement of highly energetic electrons in the outer radiation belt and its transport into the inner radiation belt inferred from MDS-1 satellite observations

    Science.gov (United States)

    Obara, T.; Matsumoto, H.

    2016-03-01

    We have examined a large increase of relativistic electrons in the outer radiation belt and its penetration into the inner radiation belt over slot region using the MDS-1 satellite observations. Result of analyses demonstrates that a large increase took place in the spring and autumn seasons, and we have newly confirmed that the penetration of outer belt electrons to the inner radiation zone took place during the big magnetic storms by examining a pitch angle distribution of the penetrating electrons.

  7. 40Ar/39Ar constraints on the timing and history of amphibolite facies gold mineralisation in the Southern Cross area, Western Australia

    International Nuclear Information System (INIS)

    Napier, R.W.; Guise, P.G.; Rex, D.C.

    1998-01-01

    The Southern Cross Greenstone Belt in Western Australia contains structurally controlled, hydrothermal gold deposits which are thought to have formed at or near the peak of amphibolite facies regional metamorphism during the Late Archaean. Although the geological features of deposits in the area are well documented. conflicting genetic models and ore-fluid sources have been used to explain the observed geological data. This paper presents new 40 Ar/ 39 Ar data which suggest that the thermal history of the Southern Cross area after the peak of regional metamorphism was more complex than has previously been suggested. After the main gold mineralisation event prior to ca 2620 Ma, the 40 Ar/ 39 Ar ages from amphiboles and biotites sampled from the alteration selvages of gold-bearing veins indicate that temperatures remained elevated in the region of 500 deg C for between 20 and 70 million years. These amphiboles and biotites from individual deposits yield ages that are in good agreement with one another to a high precision. implying increased cooling rates after the long period of elevated temperatures. Along the Southern Cross Greenstone Belt. however. amphibole-biotite pairs from the alteration selvages of gold-bearing quartz veins. while remaining in good agreement with one another, vary between deposits from ca 2560 Ma to ca 2440 Ma. Amphiboles from metabasalts that are associated with regional metamorphism and not hydrothermal alteration contain numerous exsolution lamellae that reduce the effective closure temperature of the amphiboles and yield geologically meaningless ages. These age relationships show that the thermal history of the area did not follow a simple cooling path and the area may have been tectonically active for a long period after the main gold mineralisation event before ca 2620 Ma. Such data may provide important constraints on subsequent genetic modelling of gold mineralisation and metamorphism. Copyright (1998) Blackwell Science Asia

  8. Plant trial of an under-belt capacitance and gamma-ray backscatter gauge for on-belt determination of moisture in coal

    International Nuclear Information System (INIS)

    Cutmore, N.G.; Rafter, P.T.; Abernethy, D.A.; Millen, M.J.

    1989-01-01

    A non-contacting under-belt capacitance and gamma-ray backscatter technique has been developed for the on-line measurement of moisture in coal. In this technique, moisture was correlated with radio frequency susceptance and conductance, determined using an under-belt capacitance sensor in which a fringing electric field interrogates a layer of coal on the conveyor belt directly about the sensor. To compensate for variations in the density and thickness of the coal layer, an under-belt gamma-ray backscatter gauge was used to measure an equivalent volume of coal. A plant trial of the technique was conducted at Stockton Borehole Colliery, NSW Australia, where the gauges were installed on the coking coal product conveyor. Product moistures, in the range 7-14%, were determined with r.m.s errors of 0.50 and 0.25 wt% using on-belt and static off-belt gauges, respectively. The difference in the on-belt and off-belt gauge measurement accuracy was attributed to sampling errors in the calibration of the on-belt gauge. 6 refs., 6 figs., 3 tabs

  9. Recovery of carrier-free gold-195

    International Nuclear Information System (INIS)

    Iofa, B.Z.; Ivanova, N.A.

    1995-01-01

    It is known that gold(III) is readily extracted from nitric acid solutions with ethers. The authors have studied extraction of trace amounts of gold(III) from nitric acid solutions with diethyl and diisopropyl ethers in the presence of significant excess of Pt(IV). Distribution coefficients of gold(III) were measured radiometrically using carrier-free gold-195 or spectrophotometrically in the presence of platinum(IV). Very high coefficients of gold separation from platinum may be achieved. Preliminary experiments have shown that zinc-65 was not extracted with ethers from nitric acid solutions. As an extraction system, the authors have chosen the system 10 M HNO 3 -diisopropyl ether. After model experiments, the authors have performed recovery of carrier-free gold-195 from a real platinum target irradiated with protons in a cyclotron

  10. Linear Optical Properties of Gold Colloid

    Directory of Open Access Journals (Sweden)

    Jingmin XIA

    2015-11-01

    Full Text Available Gold colloid was prepared by reducing HAuCl4·4H2O with Na3C6H5O7·2H2O. The morphology, size of gold nanoparticles and the optical property of colloid were characterized by transmission electron microscope and UV-Vis spectrophotometer, respectively. It shows that the gold nanoparticles are in the shape of spheres with diameters less than 8 nm, and the surface plasmon resonance absorption peak is located at about 438 nm. As the volume fraction of gold particles increases, the intensity of absorption peak strengthens. The optical property of gold colloid was analyzed by Maxwell-Garnett (MG effective medium theory in the company of Drude dispersion model. The results show that the matrix dielectric constant is a main factor, which influences the optical property of gold colloid.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9558

  11. Physiological investigation of gold nanorods toward watermelon.

    Science.gov (United States)

    Wan, Yujie; Li, Junli; Ren, Hongxuan; Huang, Jin; Yuan, Hong

    2014-08-01

    The objective of the present study was to evaluate the phytotoxicity and oxidant stress of the gold nanorods toward watermelon, and hence give a quantitative risk assessment of both seeds and plants phase. The seed germination, the activity of antioxidant enzymes, and the contents of soluble protein and malondialdehyde (MDA) have been measured while the plant roots were observed by transmission electron microscopy (TEM). It was found that the gold nanorods significantly promoted the root elongation. Furthermore, the results on the enzymes activities of plant indicated that oxidative stress happened in the plant treated with gold nanorods. However, the gold nanorods resulted in the phytotoxicity toward plant especially at high concentration. The TEM images of the plant roots with and without the treatment of gold nanorods showed the significant different size of starch granules. In conclusion, significant physiological changes of plant occurred after treatment with the gold nanorods.

  12. Geochemical characteristics of gold bearing boninites and banded iron formations from Shimoga greenstone belt, India: Implications for gold genesis and hydrothermal processes in diverse tectonic settings

    Digital Repository Service at National Institute of Oceanography (India)

    Ganguly, S.; Manikyamba, C.; Saha, A.; Lingadevaru, M.; Santosh, M.; Rambabu, S.; Khelen, A.C.; Purushotham, D.; Linga, D.

    .437 12 0.112 0.836 80 2.663 2.5 0.032 1.214 59 1.283 1.25 0.012 0.973 07 2.018 2 0.010 0.500 39 0.417 0.32 0.009 2.227 99 2.416 2 0.000 0.017 68 0.288 0.6 0.002 0.684 03 0.966 1.5 0.005 0.475 08 0.178 0.2 0.002 0.898 75 1.341 1.25 0.013 0.972 59 0.224 0...

  13. Paleozoic–early Mesozoic gold deposits of the Xinjiang Autonomous Region, northwestern China

    Science.gov (United States)

    Rui, Zongyao; Goldfarb, Richard J.; Qiu, Yumin; Zhou, T.; Chen, R.; Pirajno, Franco; Yun, Grace

    2002-01-01

    border and the epithermal and replacement deposits of the Kanggurtag belt to the east in the Chol Tagh range. Gold deposits of approximately the same age in the Yili block include the Axi hot springs/epithermal deposit near the Kazakhstan border and a series of small orogenic gold deposits south of Urumqi (e.g. Wangfeng). Gold-rich porphyry copper deposits (e.g. Tuwu) define important new exploration targets in the northern Tian Shan of Xinjiang. The northern foothills of the Kunlun Shan of southern Xinjiang host scattered, small placer gold deposits. Sources for the gold have not been identified, but are hypothesized to be orogenic gold veins beneath the icefields to the south. They are predicted to have formed in the Tianshuihai terrane during its early Mesozoic accretion to the amalgamated Tarim–Qaidam–Kunlun cratonic block.

  14. Gold and Silver Extraction from Leach Solutions

    Directory of Open Access Journals (Sweden)

    Bagdaulet K. Kenzhaliyev

    2014-03-01

    Full Text Available There has been carried out an investigation on the extraction of gold and silver from thiosulfate solutions: standard test and technological solutions of chemical and electrochemical leaching. The influence of related metals on the process of extracting gold from solution was studied. There has been conducted a comparative study of the IR spectra of solutions after the sorption of gold, silver and related metals.

  15. Geochemical indicators of gold ore fields

    International Nuclear Information System (INIS)

    Shcherbakov, Yu.G.

    1995-01-01

    The principles of selection of indicators for genetic reconstructions and prognostic valuations of gold mineralization of diverse morphological and geochemical types have been substantiated. The neutron-activation analysis with radiochemical separation and detection limit of 1-10 -8 %, instrumental neutron-activation analysis and atomic-absorption analysis are the main methods of determination of gold low contents in the rocks, as well as diverse elements, including transition, rare earth elements and tellurium, in gold. 50 refs.; 1 fig.; 3 tabs

  16. Glyco-gold nanoparticles: synthesis and applications

    OpenAIRE

    Compostella, Federica; Pitirollo, Olimpia; Silvestri, Alessandro; Polito, Laura

    2017-01-01

    Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco ...

  17. Glyco-gold nanoparticles: synthesis and applications

    Directory of Open Access Journals (Sweden)

    Federica Compostella

    2017-05-01

    Full Text Available Glyco-gold nanoparticles combine in a single entity the peculiar properties of gold nanoparticles with the biological activity of carbohydrates. The result is an exciting nanosystem, able to mimic the natural multivalent presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco nanoparticle design.

  18. Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel.

    Science.gov (United States)

    Yuan, Liming; Smith, Alex C

    2015-05-01

    Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect.

  19. DEVELOPMENT OF THE TEST METHODS OF THE CONVEYOR BELTS USED IN ENVIRONMENTS ENDANGERED BY EXPLOSION HAZARDS

    Directory of Open Access Journals (Sweden)

    Florin Adrian PĂUN

    2012-05-01

    Full Text Available Conveyor belts are used for a long period of time in the industry branches where potentially explosive atmospheres could occur. Dangerous phenomena which can be in direct connection with the use of conveyor belts are the ones regarding: - sparks influence over the coating layer and/or resistance internal structure of the stopped conveyor belt; - propagation of a flame along the length of a conveyor belt that was exposed to a energy source relative high like a fire or due to blockage of a conveyor belt as a result of the driving mechanism still operating, that generate a local heating of the conveyor belt in contact with the driving drum, rollers or any other heating source generated by friction. Determining the safety parameters characteristic of the conveyor belts by employing test methods allows assessment of the safety level as well as certification of their explosion protection quality when used in environments with explosion danger.

  20. Dynamics of the earth's radiation belts and inner magnetosphere (geophysical monograph series)

    CERN Document Server

    2013-01-01

    Dynamics of the Earth's Radiation Belts and Inner Magnetosphere draws together current knowledge of the radiation belts prior to the launch of Radiation Belt Storm Probes (RPSP) and other imminent space missions, making this volume timely and unique. The volume will serve as a useful benchmark at this exciting and pivotal period in radiation belt research in advance of the new discoveries that the RPSP mission will surely bring. Highlights include the following: a review of the current state of the art of radiation belt science; a complete and up-to-date account of the wave-particle interactions that control the dynamical acceleration and loss processes of particles in the Earth's radiation belts and inner magnetosphere; a discussion emphasizing the importance of the cross-energy coupling of the particle populations of the radiation belts, ring current, and plasmasphere in controlling the dynamics of the inner magnetosphe...

  1. Numerical modeling of water spray suppression of conveyor belt fires in a large-scale tunnel

    Science.gov (United States)

    Yuan, Liming; Smith, Alex C.

    2015-01-01

    Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect. PMID:26190905

  2. Coal gold agglomeration: an innovative approach to the recovery of gold in environmentally sensitive areas

    Energy Technology Data Exchange (ETDEWEB)

    Wall, N.C.; Hughes-Narborough, C.; Willey, G. [Davy (Stockton) Ltd., Stockton-on-Tees (United Kingdom)

    1994-11-01

    Coal Gold Agglomeration (CGA) was developed by BP Minerals and involves the selective recovery of oleophilic gold particles from an aqueous slurry into coal-oil agglomerates. These agglomerates are allowed to build up to a high gold loading and are then separated from the slurry. The loaded agglomerates are burned and the gold is finally recovered from the ash residue by dissolution and precipitation or by direct smelting. 6 figs.

  3. Gold nano-particles fixed on glass

    International Nuclear Information System (INIS)

    Worsch, Christian; Wisniewski, Wolfgang; Kracker, Michael; Rüssel, Christian

    2012-01-01

    Highlights: ► We produced wear resistant gold–ruby coatings on amorphous substrates. ► Thin sputtered gold layers were covered by or embedded in silica coatings. ► Annealing above T g of the substrate glass led to the formation of gold nano particles. ► A 1 1 1-texture of the gold particles is observed via XRD and EBSD. ► EBSD-patterns can be acquired from crystals covered by a thin layer of glass. - Abstract: A simple process for producing wear resistant gold nano-particle coatings on transparent substrates is proposed. Soda-lime-silica glasses were sputtered with gold and subsequently coated with SiO 2 using a combustion chemical vapor deposition technique. Some samples were first coated with silica, sputtered with gold and then coated with a second layer of silica. The samples were annealed for 20 min at either 550 or 600 °C. This resulted in the formation of round, well separated gold nano-particles with sizes from 15 to 200 nm. The color of the coated glass was equivalent to that of gold–ruby glasses. Silica/gold/silica coatings annealed at 600 °C for 20 min were strongly adherent and scratch resistant. X-ray diffraction and electron backscatter diffraction (EBSD) were used to describe the crystal orientations of the embedded particles. The gold particles are preferably oriented with their (1 1 1) planes perpendicular to the surface.

  4. CO oxidation on gold nanoparticles: Theoretical studies

    DEFF Research Database (Denmark)

    Remediakis, Ioannis; Lopez, Nuria; Nørskov, Jens Kehlet

    2005-01-01

    We present a summary of our theoretical results regarding CO oxidation on both oxide-supported and isolated gold nanoparticles. Using Density Functional Theory we have studied the adsorption of molecules and the oxidation reaction of CO on gold clusters. Low-coordinated sites on the gold...... nanoparticles can adsorb small inorganic molecules such as O2 and CO, and the presence of these sites is the key factor for the catalytic properties of supported gold nanoclusters. Other contributions, induced by the presence of the support, can provide parallel channels for the reaction and modulate the final...

  5. Gold Rushes and mineral property rights allocation

    DEFF Research Database (Denmark)

    Sinding, Knud

    , is to handle the other projects that are generated by the "gold rush" informational externalities created by the initial discovery. At the core of the problems of dealing with a gold rush situation is both the informational externality and an institutional framework which is not designed to deal with large...... influxes of prospectors competing for a very limited area. This paper charts significant gold rush events in the mineral industry in recent decades and uses preliminary data on the areas impacted by these gold rushes to argue that many mineral tenure systems should be modified in order to be better able...

  6. Proterozoic orogenic belts and rifting of Indian cratons: Geophysical constraints

    Directory of Open Access Journals (Sweden)

    D.C. Mishra

    2014-01-01

    Full Text Available The Aravalli–Delhi and Satpura Mobile Belts (ADMB and SMB and the Eastern Ghat Mobile Belt (EGMB in India form major Proterozoic mobile belts with adjoining cratons and contemporary basins. The most convincing features of the ADMB and the SMB have been the crustal layers dipping from both sides in opposite directions, crustal thickening (∼45 km and high density and high conductivity rocks in upper/lower crust associated with faults/thrusts. These observations indicate convergence while domal type reflectors in the lower crust suggest an extensional rifting phase. In case of the SMB, even the remnant of the subducting slab characterized by high conductive and low density slab in lithospheric mantle up to ∼120 km across the Purna–Godavari river faults has been traced which may be caused by fluids due to metamorphism. Subduction related intrusives of the SMB south of it and the ADMB west of it suggest N–S and E–W directed convergence and subduction during Meso–Neoproterozoic convergence. The simultaneous E–W convergence between the Bundelkhand craton and Marwar craton (Western Rajasthan across the ADMB and the N–S convergence between the Bundelkhand craton and the Bhandara and Dharwar cratons across the SMB suggest that the forces of convergence might have been in a NE–SW direction with E–W and N–S components in the two cases, respectively. This explains the arcuate shaped collision zone of the ADMB and the SMB which are connected in their western part. The Eastern Ghat Mobile Belt (EGMB also shows signatures of E–W directed Meso–Neoproterozoic convergence with East Antarctica similar to ADMB in north India. Foreland basins such as Vindhyan (ADMB–SMB, and Kurnool (EGMB Supergroups of rocks were formed during this convergence. Older rocks such as Aravalli (ADMB, Mahakoshal–Bijawar (SMB, and Cuddapah (EGMB Supergroups of rocks with several basic/ultrabasic intrusives along these mobile belts, plausibly formed during

  7. Nuclear excitation in muonic gold

    CERN Document Server

    Robert Tissot, B; Debrunner, P; Engfer, R; Link, R; Schellenberg, L; Schneuwly, H; Walter, H K

    1973-01-01

    Energies and intensities of muonic X-rays in gold were measured at the CERN muon channel with an experimental set-up as described by Backe et al. (1972). The 2p-1s and 3d-2p transitions could only be analysed taking into account beside the static quadrupole interaction a dynamical hyperfine interaction of the 2p states, which leads to an excitation of the first four nuclear levels. The dynamical hyperfine interaction was calculated using the core excitation model (de Shalit, (1961)). (0 refs).

  8. The Resonance Integral of Gold

    Energy Technology Data Exchange (ETDEWEB)

    Jirlow, K; Johansson, E

    1959-04-15

    The resonance activation integral of gold has been determined, by means of cadmium ratio measurements of thin foils in a neutron beam. Comparison was made with a 1/v detector, and the neutron spectra were measured with a chopper. The resonance integral, RI, is defined as {integral}{sub 0.5}{sup {infinity}}{sigma}{sub r}(E)dE/E, where {sigma}{sub r}(E) is the differenc between the total absorption cross section and the 1/v part. An experimental value of 1490 {+-} 40 barns has been obtained. RI has also been computed from resonance parameter data with the result 1529 {+-} 70 barns.

  9. Critical phenomenon of granular flow on a conveyor belt.

    Science.gov (United States)

    De-Song, Bao; Xun-Sheng, Zhang; Guang-Lei, Xu; Zheng-Quan, Pan; Xiao-Wei, Tang; Kun-Quan, Lu

    2003-06-01

    The relationship between the granular wafer movement on a two-dimensional conveyor belt and the size of the exit together with the velocity of the conveyor belt has been studied in the experiment. The result shows that there is a critical speed v(c) for the granular flow when the exit width d is fixed (where d=R/D, D being the diameter of a granular wafers). When vv(c), the flow rate Q is described as Q=Crho(v)(beta)(d-k)(3/2). These are the effects of the interaction among the granular wafers and the change of the states of the granular flow due to the changing of the speed or the exit width d.

  10. Design of temperature detection device for drum of belt conveyor

    Science.gov (United States)

    Zhang, Li; He, Rongjun

    2018-03-01

    For difficult wiring and big measuring error existed in the traditional temperature detection method for drum of belt conveyor, a temperature detection device for drum of belt conveyor based on Radio Frequency(RF) communication is designed. In the device, detection terminal can collect temperature data through tire pressure sensor chip SP370 which integrates temperature detection and RF emission. The receiving terminal which is composed of RF receiver chip and microcontroller receives the temperature data and sends it to Controller Area Network(CAN) bus. The test results show that the device meets requirements of field application with measuring error ±3.73 ° and single button battery can provide continuous current for the detection terminal over 1.5 years.

  11. Health impact assessment of the Atlanta BeltLine.

    Science.gov (United States)

    Ross, Catherine L; Leone de Nie, Karen; Dannenberg, Andrew L; Beck, Laurie F; Marcus, Michelle J; Barringer, Jason

    2012-03-01

    Although a health impact assessment (HIA) is a tool that can provide decision makers with recommendations to promote positive health impacts and mitigate adverse health impacts of proposed projects and policies, it is not routinely conducted on most major projects or policies. To make health a decision criterion for the Atlanta BeltLine, a multibillion-dollar transit, trails, parks, and redevelopment project. An HIA was conducted in 2005-2007 to anticipate and influence the BeltLine's effect on health determinants. Changes in access and equity, environmental quality, safety, social capital, and physical activity were forecast, and steps to maximize health benefits and reduce negative effects were recommended. Key recommendations included giving priority to the construction of trails and greenspace rather than residential and retail construction, making health an explicit goal in project priority setting, adding a public health professional to decision-making boards, increasing the connectivity between the BeltLine and civic spaces, and ensuring that affordable housing is built. BeltLine project decision makers have incorporated most of the HIA recommendations into the planning process. The HIA was cited in the awarding of additional funds of $7,000,000 for brownfield clean-up and greenspace development. The project is expected to promote the health of local residents more than in the absence of the HIA. This report is one of the first HIAs to tie specific assessment findings to specific recommendations and to identifiable impacts from those recommendations. The lessons learned from this project may help others engaged in similar efforts. Copyright © 2012. Published by Elsevier Inc.

  12. Nonlinear Whistler Wave Physics in the Radiation Belts

    Science.gov (United States)

    Crabtree, Chris

    2016-10-01

    Wave particle interactions between electrons and whistler waves are a dominant mechanism for controlling the dynamics of energetic electrons in the radiation belts. They are responsible for loss, via pitch-angle scattering of electrons into the loss cone, and energization to millions of electron volts. It has previously been theorized that large amplitude waves on the whistler branch may scatter their wave-vector nonlinearly via nonlinear Landau damping leading to important consequences for the global distribution of whistler wave energy density and hence the energetic electrons. It can dramatically reduce the lifetime of energetic electrons in the radiation belts by increasing the pitch angle scattering rate. The fundamental building block of this theory has now been confirmed through laboratory experiments. Here we report on in situ observations of wave electro-magnetic fields from the EMFISIS instrument on board NASA's Van Allen Probes that show the signatures of nonlinear scattering of whistler waves in the inner radiation belts. In the outer radiation belts, whistler mode chorus is believed to be responsible for the energization of electrons from 10s of Kev to MeV energies. Chorus is characterized by bursty large amplitude whistler mode waves with frequencies that change as a function of time on timescales corresponding to their growth. Theories explaining the chirping have been developed for decades based on electron trapping dynamics in a coherent wave. New high time resolution wave data from the Van Allen probes and advanced spectral techniques are revealing that the wave dynamics is highly structured, with sub-elements consisting of multiple chirping waves with discrete frequency hops between sub-elements. Laboratory experiments with energetic electron beams are currently reproducing the complex frequency vs time dynamics of whistler waves and in addition revealing signatures of wave-wave and beat-wave nonlinear wave-particle interactions. These new data

  13. Migmatitic rocks southwest of the Barberton greenstone belt

    International Nuclear Information System (INIS)

    Robb, L.J.; Anhaeusser, C.R.

    1981-01-01

    A geologic survey was done on the migmatitic rocks southwest of the Barberton greenstone belt. A table is given on the chemical analyses of components from migmatic outcrops in this area, as well as on the chemical analyses of some selected rock types found in greenstone xenoliths, together with leuco-biotite tomalite/tronomjemite gneisses in the area surrounding the Boesmanskop syenite pluton. Isotope dating was also used in the survey

  14. Anomalous heat flow belt along the continental margin of Brazil

    Science.gov (United States)

    Hamza, Valiya M.; Vieira, Fabio P.; Silva, Raquel T. A.

    2018-01-01

    A comprehensive analysis of thermal gradient and heat flow data was carried out for sedimentary basins situated in the continental margin of Brazil (CMB). The results point to the existence of a narrow belt within CMB, where temperature gradients are higher than 30 °C/km and the heat flow is in excess of 70 mW/m2. This anomalous geothermal belt is confined between zones of relatively low to normal heat flow in the adjacent continental and oceanic regions. The width of the belt is somewhat variable, but most of it falls within the range of 100-300 km. The spatial extent is relatively large in the southern (in the basins of Pelotas, Santos and Campos) and northern (in the basins of Potiguar and Ceará) parts, when compared with those in the central parts (in the basins of South Bahia, Sergipe and Alagoas). The characteristics of heat flow anomalies appear to be compatible with those produced by thermal sources at depths in the lower crust. Hence, magma emplacement at the transition zone between lower crust and upper mantle is considered the likely mechanism producing such anomalies. Seismicity within the belt is relatively weak, with focal depths less than 10 km for most of the events. Such observations imply that "tectonic bonding" between continental and oceanic segments, at the transition zone of CMB, is relatively weak. Hence, it is proposed that passive margins like CMB be considered as constituting a type of plate boundary that is aseismic at sub-crustal levels, but allows for escape of significant amounts of earth's internal heat at shallow depths.

  15. Accelerated Comparative Fatigue Strength Testing of Belt Adhesive Joints

    Science.gov (United States)

    Bajda, Miroslaw; Blazej, Ryszard; Jurdziak, Leszek

    2017-12-01

    Belt joints are the weakest link in the serial structure that creates an endless loop of spliced belt segments. This affects not only the lower strength of adhesive joints of textile belts in comparison to vulcanized splices, but also the replacement of traditional glues to more ecological but with other strength parameters. This is reflected in the lowered durability of adhesive joints, which in underground coal mines is nearly twice shorter than the operating time of belts. Vulcanized splices require high precision in performance, they need long time to achieve cross-linking of the friction mixture and, above all, they require specialized equipment (vulcanization press) which is not readily available and often takes much time to be delivered down, which means reduced mining output or even downtime. All this reduces the reliability and durability of adhesive joints. In addition, due to the consolidation on the Polish coal market, mines are joined into large economic units serviced by a smaller number of processing plants. The consequence is to extend the transport routes downstream and increase reliability requirements. The greater number of conveyors in the chain reduces reliability of supply and increases production losses. With high fixed costs of underground mines, the reduction in mining output is reflected in the increase in unit costs, and this at low coal prices on the market can mean substantial losses for mines. The paper describes the comparative study of fatigue strength of shortened samples of adhesive joints conducted to compare many different variants of joints (various adhesives and materials). Shortened samples were exposed to accelerated fatigue in the usually long-lasting dynamic studies, allowing more variants to be tested at the same time. High correlation between the results obtained for shortened (100 mm) and traditional full-length (3×250 mm) samples renders accelerated tests possible.

  16. Geochemical methodology for gold prospect ion in Uruguay

    International Nuclear Information System (INIS)

    Spangenber, J.

    1987-01-01

    This work is about the history of gold prospection in Uruguay. In this study there are considered the geochemical aspects, the gold performance, the applicability to mining prospection and the gold prospection aluvionar

  17. A social media program to increase adolescent seat belt use.

    Science.gov (United States)

    Drake, Stacy A; Zhang, Ni; Applewhite, Courtney; Fowler, Katherine; Holcomb, John B

    2017-09-01

    In response to motor vehicle crashes remaining the leading cause of death for teenagers in the United States, a nursing clinical group (n = 10) in conjunction with a local hospital injury prevention program created an educational campaign to bolster seat belt use. The nursing students created an Instagram account to serve as an educational tool to promote seat belt use among teenagers aged 14-19, and the program was presented at three high school health fairs. In all, 135 postings were made to the account over a 3-month period. The number of likes posted by high school students was the unit of analysis. The most significant result (p = .01) was the difference between postings most liked (celebrities wearing seat belts) and least liked (postings made at the high school health fair), otherwise, differences among postings liked (humor postings, response requests, pictures of celebrities, factual data) were not significant. Instagram user engagement, measured in number of likes, is indicative that social media provides platforms to promote injury prevention efforts. Further research is needed to identify measurable elements of social media and to follow-up on behavioral changes following participation. © 2017 Wiley Periodicals, Inc.

  18. The size of the auroral belt during magnetic storms

    Directory of Open Access Journals (Sweden)

    N. Yokoyama

    1998-05-01

    Full Text Available Using the auroral boundary index derived from DMSP electron precipitation data and the Dst index, changes in the size of the auroral belt during magnetic storms are studied. It is found that the equatorward boundary of the belt at midnight expands equatorward, reaching its lowest latitude about one hour before Dst peaks. This time lag depends very little on storm intensity. It is also shown that during magnetic storms, the energy of the ring current quantified with Dst increases in proportion to Le–3, where Le is the L-value corresponding to the equatorward boundary of the auroral belt designated by the auroral boundary index. This means that the ring current energy is proportional to the ion energy obtained from the earthward shift of the plasma sheet under the conservation of the first adiabatic invariant. The ring current energy is also proportional to Emag, the total magnetic field energy contained in the spherical shell bounded by Le and Leq, where Leq corresponds to the quiet-time location of the auroral precipitation boundary. The ratio of the ring current energy ER to the dipole energy Emag is typically 10%. The ring current leads to magnetosphere inflation as a result of an increase in the equivalent dipole moment.Key words. Ionosphere (Auroral ionosphere · Magnetospheric physics (Auroral phenomena; storms and substorms

  19. Nonlinear Scattering of VLF Waves in the Radiation Belts

    Science.gov (United States)

    Crabtree, Chris; Rudakov, Leonid; Ganguli, Guru; Mithaiwala, Manish

    2014-10-01

    Electromagnetic VLF waves, such as whistler mode waves, control the lifetime of trapped electrons in the radiation belts by pitch-angle scattering. Since the pitch-angle scattering rate is a strong function of the wave properties, a solid understanding of VLF wave sources and propagation in the magnetosphere is critical to accurately calculate electron lifetimes. Nonlinear scattering (Nonlinear Landau Damping) is a mechanism that can strongly alter VLF wave propagation [Ganguli et al. 2010], primarily by altering the direction of propagation, and has not been accounted for in previous models of radiation belt dynamics. Laboratory results have confirmed the dramatic change in propagation direction when the pump wave has sufficient amplitude to exceed the nonlinear threshold [Tejero et al. 2014]. Recent results show that the threshold for nonlinear scattering can often be met by naturally occurring VLF waves in the magnetosphere, with wave magnetic fields of the order of 50-100 pT inside the plasmapause. Nonlinear scattering can then dramatically alter the macroscopic dynamics of waves in the radiation belts leading to the formation of a long-lasting wave-cavity [Crabtree et al. 2012] and, when amplification is present, a multi-pass amplifier [Ganguli et al. 2012]. By considering these effects, the lifetimes of electrons can be dramatically reduced. This work is supported by the Naval Research Laboratory base program.

  20. Modeling of the outer electron belt during magnetic storms

    International Nuclear Information System (INIS)

    Desorgher, L.; Buehler, P.; Zehnder, A.; Daly, E.; Adams, L.

    1999-01-01

    The flux dropout of relativistic electrons in the earth's outer radiation belt, during the main phase of the 26 March 1995 magnetic storm is examined. Outer belt measurements by the Radiation Environment Monitor, REM aboard the STRV-1b satellite are presented to characterize this dropout. In order to simulate the dynamics of the electron belt during the storm main phase a particle tracing code was developed which allows to trace the trajectories of equatorially mirroring electrons in a dynamic magnetospheric electromagnetic field. Two simulations were performed in a non-stationary magnetic field, one taking only the induced electric field into account (fully adiabatic motion), and one with an additional non-stationary convection electric field. The simulations show, that adiabatic deceleration can produce the observed count rate decrease and also the observed inward motion of the count rate peak. The convection electric field causes diffusion, which can take particles from low L values out to the magnetopause and contribute to an additional loss of particles, which is suggested by the observations

  1. Statistical studies of energetic electrons in the outer radiation belt

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, A.D.; Rodgers, D.J.; Jones, G.H. E-mail: g.h.jones@ic.ac.uk

    1999-10-01

    The medium electron A (MEA) instrument aboard the CRRES spacecraft provided data on terrestrial radiation belt electrons in the energy range from 153 to 1582 keV, during 1990-91. These data have previously been used to produce an empirical model of the radiation belts from L=1.1 to 8.9, ordered according to 17 energy bands, 18 pitch angle bins, and 5 Kp ranges. Empirical models such as this are very valuable, but are prone to statistical fluctuations and gaps in coverage. In this study, in order to smooth the data and make it more easy to interpolate within data gaps, the pitch angle distribution at each energy in the model was fitted with a Bessel function. This provided a way to characterize the pitch angle in terms of only two parameters for each energy. It was not possible to model fluxes reliably within the loss cone because of poor statistics. The fitted distributions give an indication of the way in which pitch angle diffusion varies in the outer radiation belts. The two parameters of the Bessel function were found to vary systematically with L value, energy and Kp. Through the fitting of a simple function to these systematic variations, the number of parameters required to describe the model could be reduced drastically.

  2. Reconstructing the size distribution of the primordial Main Belt

    Science.gov (United States)

    Tsirvoulis, G.; Morbidelli, A.; Delbo, M.; Tsiganis, K.

    2018-04-01

    In this work we aim to constrain the slope of the size distribution of main-belt asteroids, at their primordial state. To do so we turn out attention to the part of the main asteroid belt between 2.82 and 2.96 AU, the so-called "pristine zone", which has a low number density of asteroids and few, well separated asteroid families. Exploiting these unique characteristics, and using a modified version of the hierarchical clustering method we are able to remove the majority of asteroid family members from the region. The remaining, background asteroids should be of primordial origin, as the strong 5/2 and 7/3 mean-motion resonances with Jupiter inhibit transfer of asteroids to and from the neighboring regions. The size-frequency distribution of asteroids in the size range 17 size distribution slope q = - 1.43 . In addition, applying the same 'family extraction' method to the neighboring regions, i.e. the middle and outer belts, and comparing the size distributions of the respective background populations, we find statistical evidence that no large asteroid families of primordial origin had formed in the middle or pristine zones.

  3. Gold emissivities for hydrocode applications

    Science.gov (United States)

    Bowen, C.; Wagon, F.; Galmiche, D.; Loiseau, P.; Dattolo, E.; Babonneau, D.

    2004-10-01

    The Radiom model [M. Busquet, Phys Fluids B 5, 4191 (1993)] is designed to provide a radiative-hydrodynamic code with non-local thermodynamic equilibrium (non-LTE) data efficiently by using LTE tables. Comparison with benchmark data [M. Klapisch and A. Bar-Shalom, J. Quant. Spectrosc. Radiat. Transf. 58, 687 (1997)] has shown Radiom to be inaccurate far from LTE and for heavy ions. In particular, the emissivity was found to be strongly underestimated. A recent algorithm, Gondor [C. Bowen and P. Kaiser, J. Quant. Spectrosc. Radiat. Transf. 81, 85 (2003)], was introduced to improve the gold non-LTE ionization and corresponding opacity. It relies on fitting the collisional ionization rate to reproduce benchmark data given by the Averroès superconfiguration code [O. Peyrusse, J. Phys. B 33, 4303 (2000)]. Gondor is extended here to gold emissivity calculations, with two simple modifications of the two-level atom line source function used by Radiom: (a) a larger collisional excitation rate and (b) the addition of a Planckian source term, fitted to spectrally integrated Averroès emissivity data. This approach improves the agreement between experiments and hydrodynamic simulations.

  4. Gold emissivities for hydrocode applications

    International Nuclear Information System (INIS)

    Bowen, C.; Wagon, F.; Galmiche, D.; Loiseau, P.; Dattolo, E.; Babonneau, D.

    2004-01-01

    The Radiom model [M. Busquet, Phys Fluids B 5, 4191 (1993)] is designed to provide a radiative-hydrodynamic code with non-local thermodynamic equilibrium (non-LTE) data efficiently by using LTE tables. Comparison with benchmark data [M. Klapisch and A. Bar-Shalom, J. Quant. Spectrosc. Radiat. Transf. 58, 687 (1997)] has shown Radiom to be inaccurate far from LTE and for heavy ions. In particular, the emissivity was found to be strongly underestimated. A recent algorithm, Gondor [C. Bowen and P. Kaiser, J. Quant. Spectrosc. Radiat. Transf. 81, 85 (2003)], was introduced to improve the gold non-LTE ionization and corresponding opacity. It relies on fitting the collisional ionization rate to reproduce benchmark data given by the Averroes superconfiguration code [O. Peyrusse, J. Phys. B 33, 4303 (2000)]. Gondor is extended here to gold emissivity calculations, with two simple modifications of the two-level atom line source function used by Radiom: (a) a larger collisional excitation rate and (b) the addition of a Planckian source term, fitted to spectrally integrated Averroes emissivity data. This approach improves the agreement between experiments and hydrodynamic simulations

  5. Metamorphic rock-hosted orogenic gold deposit style at Bombana (Southeast Sulawesi and Buru Island (Maluku: Their key features and significances for gold exploration in Eastern Indonesia

    Directory of Open Access Journals (Sweden)

    Arifudin Idrus

    2017-06-01

    Full Text Available In Indonesia, gold is commonly mined from epithermal-, porphyry-, and skarn-type deposits that are commonly found in volcanic belts along island arcs or active continental margin settings. Numerous gold prospects, however, were recently discovered in association with metamorphic rocks. This paper focuses on metamorphic rock-hosted gold mineralization in Eastern Indonesia, in particular the Bombana (SE Sulawesi and Buru Island (Maluku prospects. At Bombana, gold-bearing quartz-veins are hosted by the Pompangeo metamorphic complex. Sheared, segmented veins vary in thickness from 2 cm to 2 m. Gold is mainly present in the form of ‘free gold’ among silicate minerals and closely related to cinnabar, stibnite, tripuhyite, and in places, minor arsenopyrite. The gold distribution is erratic, however, ranging from below detection limit up to 134 g/t. At least three generations of veins are identified. The first is parallel to the foliation, the second crosscuts the first generation of veins as well as the foliation, and the late-stage laminated deformed quartz-calcite vein represents the third mineralization stage. The early veins are mostly massive to crystalline, occasionally brecciated, and sigmoidal, whereas the second-stage veins are narrower than the first ones and less subjected to brecciation. Gold grades in the second- and third-stage veins are on average higher than that in the earlier veins. Microthermometric and Raman spectrometric studies of fluid inclusions indicate abundant H2O-NaCl and minor H2O-NaCl-CO2 fluids. Homogenization temperatures and salinities vary from 114 to 283 ºC and 0.35 to 9.08 wt.% NaCl eq., respectively. Crush-leach analysis of fluid inclusions suggests that the halogen fluid chemistry is not identical to sea water, magmatic or epithermal related fluids, but tends to be similar to fluids in mesothermal-type gold deposits. In Buru Island (Gunung Botak and Gogorea prospects, two distinct generations of quartz veins

  6. Paper Money but a Gold Debt. Italy in the Gold Standard

    OpenAIRE

    Giuseppe Tattara; or consequences)

    2002-01-01

    During the 52 years between the Unification of the Kingdom of Italy and World War 1, the lira was legally convertible into metal for a limited period of time. Although not formally committed to gold, the lira exchange towards the gold standard countries proved remarkably stable, \\223shadowing\\224 gold. It is widely claimed that being one of the successful members of the gold standard circle entailed a number of advantages. If the lira was closely linked to gold, suggesting that there was only...

  7. Spherical aggregates composed of gold nanoparticles

    International Nuclear Information System (INIS)

    Chen, C-C; Kuo, P-L; Cheng, Y-C

    2009-01-01

    Alkylated triethylenetetramine (C12E3) was synthesized and used as both a reductant in the preparation of gold nanoparticles by the reduction of HAuCl 4 and a stabilizer in the subsequent self-assembly of the gold nanoparticles. In acidic aqueous solution, spherical aggregates (with a diameter of about 202 ± 22 nm) of gold nanoparticles (with the mean diameter of ∼18.7 nm) were formed. The anion-induced ammonium adsorption of the alkylated amines on the gold nanoparticles was considered to provide the electrostatic repulsion and steric hindrance between the gold nanoparticles, which constituted the barrier that prevented the individual particles from coagulating. However, as the amino groups became deprotonated with increasing pH, the ammonium adsorption was weakened, and the amino groups were desorbed from the gold surface, resulting in discrete gold particles. The results indicate that the morphology of the reduced gold nanoparticles is controllable through pH-'tunable' aggregation under the mediation of the amino groups of alkylated amine to create spherical microstructures.

  8. Nonlinear optical studies of single gold nanoparticles

    NARCIS (Netherlands)

    Dijk, Meindert Alexander van

    2007-01-01

    Gold nanoparticles are spherical clusters of gold atoms, with diameters typically between 1 and 100 nanometers. The applications of these particles are rather diverse, from optical labels for biological experiments to data carrier for optical data storage. The goal of my project was to develop new

  9. Ionization model for nickel-like gold

    International Nuclear Information System (INIS)

    Busquet, M.; Bruneau, J.

    1986-04-01

    Before we build an extensive population model for gold ionized 49 to 52 times, we have studied with a more simple model the effect of accounting for cascades (or dielectronic recombination) and Δn = 0 transitions. These transitions allow some understanding of typical feature of experimental gold spectra

  10. The Stability of Supported Gold Catalysts

    NARCIS (Netherlands)

    Masoud, Nazila

    2018-01-01

    Gold has supreme cultural and financial value and, in form of nanoparticles smaller than 10 nm, is a unique catalyst for different industrially relevant reactions. Intriguing properties of the gold catalysts have spurred demand in the chemical industry for Au catalysts, the application of which

  11. Goudafzettingen in Suriname (Gold deposits in Surinam)

    NARCIS (Netherlands)

    Brinck, J.W.

    1956-01-01

    THE GOLD DEPOSITS IN SURINAM AND THE DISTRIBUTION OF CONCESSIONS THROUGH THE COUNTRY The fieldwork on the occurrence of primary and secondary gold deposits in Surinam on which this thesis is based was carried out by order of the Welfare Fund Surinam (Welvaarts Fonds Suriname) during the periods

  12. Gold - Old Drug with New Potentials.

    Science.gov (United States)

    Faa, Gavino; Gerosa, Clara; Fanni, Daniela; Lachowicz, Joanna I; Nurchi, Valeria M

    2018-01-01

    Research into gold-based drugs for a range of human diseases has seen a revival in recent years. This article reviews the most important applications of gold products in different fields of human pathology. Au(I) and Au(III) compounds have been re-introduced in clinical practice for targeting the cellular components involved in the onset and progression of viral and parasitic diseases, rheumatoid arthritis and cancer. After some brief historical notes, this article takes into account the applications of gold compounds against Mycobacterium tuberculosis, and also in tuberculosis and in rheumatoid arthritis treatment. The use of gold containing drugs in the cure of cancer are then considered, with special emphasis to the use of nanoparticles and to the photo-thermal cancer therapy. The use of colloidal gold in diagnostics, introduced in the last decade is widely discussed. As a last point a survey on the adverse effects and on the toxicity of the various gold derivatives in use in medicine is presented. In this review, we described the surprisingly broad spectrum of possible uses of gold in diagnostics and in therapeutic approaches to multiple human diseases, ranging from degenerative to infectious diseases, and to cancer. In particular, gold nanoparticles appear as attractive elements in modern clinical medicine, combining high therapeutic properties, high selectivity in targeting cancer cells and low toxicity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Numerical simulations of nanostructured gold films

    DEFF Research Database (Denmark)

    Repän, Taavi; Frydendahl, Christian; Novikov, Sergey M.

    2017-01-01

    We present an approach to analyse near-field effects on nanostructured gold films by finite element simulations. The studied samples are formed by fabricating gold films near the percolation threshold and then applying laser damage. Resulting samples have complicated structures, which...

  14. A Computerized Tomography Study of Vocal Tract Setting in Hyperfunctional Dysphonia and in Belting.

    Science.gov (United States)

    Saldias, Marcelo; Guzman, Marco; Miranda, Gonzalo; Laukkanen, Anne-Maria

    2018-04-03

    Vocal tract setting in hyperfunctional patients is characterized by a high larynx and narrowing of the epilaryngeal and pharyngeal region. Similar observations have been made for various singing styles, eg, belting. The voice quality in belting has been described to be loud, speech like, and high pitched. It is also often described as sounding "pressed" or "tense". The above mentioned has led to the hypothesis that belting may be strenuous to the vocal folds. However, singers and teachers of belting do not regard belting as particularly strenuous. This study investigates possible similarities and differences between hyperfunctional voice production and belting. This study concerns vocal tract setting. Four male patients with hyperfunctional dysphonia and one male contemporary commercial music singer were registered with computerized tomography while phonating on [a:] in their habitual speaking pitch. Additionally, the singer used the pitch G4 in belting. The scannings were studied in sagittal and transversal dimensions by measuring lengths, widths, and areas. Various similarities were found between belting and hyperfunction: high vertical larynx position, small hypopharyngeal width, and epilaryngeal outlet. On the other hand, belting differed from dysphonia (in addition to higher pitch) by a wider lip and jaw opening, and larger volumes of the oral cavity. Belting takes advantage of "megaphone shape" of the vocal tract. Future studies should focus on modeling and simulation to address sound energy transfer. Also, they should consider aerodynamic variables and vocal fold vibration to evaluate the "price of decibels" in these phonation types. Copyright © 2018. Published by Elsevier Inc.

  15. Gold 100: proceedings of the international conference on gold. V. 2

    International Nuclear Information System (INIS)

    Fivaz, C.E.; King, R.P.

    1986-01-01

    The proceedings of Gold 100 have been published in three separate volumes. The first deals with the mining of gold, the second with the extractive metallurgy of gold, and the third with industrial uses of gold. In this second volume, the papers on extractive metallurgy presented at the Conference reflect most of the problems that are currently of significant technical interest to the industry. This volume is divided in six main parts covering plant design, carbon-in-pulp technology, refractory gold, new technology, grinding and concentration, and leaching. The part on new technology includes papers on x-ray fluorescence analyzers, Moessbauer spectroscopy and leaching processes for uranium, while the part on grinding and concentration includes papers on nuclear and radiotracer techniques for the recovery of gold as well as various flotation parameters in the flotation behaviour of gold and uranium

  16. Gold analysis by the gamma absorption technique

    International Nuclear Information System (INIS)

    Kurtoglu, Arzu; Tugrul, A.B.

    2003-01-01

    Gold (Au) analyses are generally performed using destructive techniques. In this study, the Gamma Absorption Technique has been employed for gold analysis. A series of different gold alloys of known gold content were analysed and a calibration curve was obtained. This curve was then used for the analysis of unknown samples. Gold analyses can be made non-destructively, easily and quickly by the gamma absorption technique. The mass attenuation coefficients of the alloys were measured around the K-shell absorption edge of Au. Theoretical mass attenuation coefficient values were obtained using the WinXCom program and comparison of the experimental results with the theoretical values showed generally good and acceptable agreement

  17. Synthesis of camptothecin-loaded gold nanomaterials

    International Nuclear Information System (INIS)

    Xing Zhimin; Liu Zhiguo; Zu Yuangang; Fu Yujie; Zhao Chunjian; Zhao Xiuhua; Meng Ronghua; Tan Shengnan

    2010-01-01

    Camptothecin-loaded gold nanomaterials have been synthesized by the sodium borohydride reduction method under a strong basic condition. The obtained gold nanomaterials have been characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV-vis absorption spectroscopy. The camptothecin-loaded gold colloidal solution was very stable and can be stored for more than two months at room temperature without obvious changes. The color of the colloidal solution can change from wine red to purple and blue during the acidifying process. It was revealed that the release of camptothecin and the aggregation of gold nanoparticles can be controlled by tuning the solution pH. The present study implied that the gold nanomaterials can be used as the potential carrier for CPT delivery.

  18. Hydrofluorination of Alkynes Catalysed by Gold Bifluorides.

    Science.gov (United States)

    Nahra, Fady; Patrick, Scott R; Bello, Davide; Brill, Marcel; Obled, Alan; Cordes, David B; Slawin, Alexandra M Z; O'Hagan, David; Nolan, Steven P

    2015-01-01

    We report the synthesis of nine new N -heterocyclic carbene gold bifluoride complexes starting from the corresponding N -heterocyclic carbene gold hydroxides. A new methodology to access N,N' -bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) fluoride starting from N,N' -bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) hydroxide and readily available potassium bifluoride is also reported. These gold bifluorides were shown to be efficient catalysts in the hydrofluorination of symmetrical and unsymmetrical alkynes, thus affording fluorinated stilbene analogues and fluorovinyl thioethers in good to excellent yields with high stereo- and regioselectivity. The method is exploited further to access a fluorinated combretastatin analogue selectively in two steps starting from commercially available reagents.

  19. Synthesis of camptothecin-loaded gold nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Xing Zhimin [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Liu Zhiguo, E-mail: zguoliu@yahoo.com.cn [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Zu Yuangang, E-mail: nefunano@yahoo.com.cn [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Fu Yujie; Zhao Chunjian; Zhao Xiuhua; Meng Ronghua; Tan Shengnan [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China)

    2010-04-01

    Camptothecin-loaded gold nanomaterials have been synthesized by the sodium borohydride reduction method under a strong basic condition. The obtained gold nanomaterials have been characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV-vis absorption spectroscopy. The camptothecin-loaded gold colloidal solution was very stable and can be stored for more than two months at room temperature without obvious changes. The color of the colloidal solution can change from wine red to purple and blue during the acidifying process. It was revealed that the release of camptothecin and the aggregation of gold nanoparticles can be controlled by tuning the solution pH. The present study implied that the gold nanomaterials can be used as the potential carrier for CPT delivery.

  20. Creating and destroying mountain belts in a sandbox (Invited)

    Science.gov (United States)

    Hernandez, M.

    2009-12-01

    M. Hernandez-1, L. Cruz-1, G. Hilley-1, J. Malinski-1, W.A. Take-2 1-Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 2-Department of Civil Engineering, Queen's University, Kingston, Canada This study uses a new experimental approach to model the kinematic response of the Aconcagua fold-and-thrust belt to erosion using a deforming sand wedge that is eroded according to a fluvial bedrock incision rule. Our objective is to thoroughly examine the impact that erosion may have had on the kinematics of this fold-and-thrust belt and test the applicability of our approach. Our experimental apparatus allows for a variety of boundary conditions to be applied to the wedge, including constant displacement rate, time-varying displacement rate, constant loading, and time-varying loading. This setting also includes three digital cameras that are connected to the apparatus to monitor the top and one side of the experimental sandbox. In this new experimental approach, as we deform the sand wedge, or mountain belt, we select specific time intervals to calculate, using a Matlab code, the topographic slope derived from our erosion rule. We then use a linear laser to project the calculated topographic slope into the sand wedge and remove any excess of sand with a vacuum cleaner. We then let the wedge continue to deform and repeat the above process. After the end of each experiment, we use Particle Image Velocimetry (PIV) techniques to analyze the movement of the sand particles throughout the experiment. The use of PIV requires the images from all three cameras to be corrected due to lens distortion. We use available software, such as Photoshop, to correct and crop the images. The results of our constant-displacement rate experiments indicate, based on geometric comparisons against natural topographic measurements, that our erosional rule could be satisfactorily applied to sandbox simulations. Each of the main deformational stages identified in the

  1. Development of high torque belt CVT with torque converter; Torque converter tsuki daiyoryogata belt CVT no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kurosawa, M; Fujikawa, T; Yoshida, K; Kobayahi, M [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    Nissan has successfully developed a new belt CVT (Continuously Variable Transmission) with torque converter and has installed it 2L-class vehicle for the first time in the world. This paper describes about the technology of high torque transmission, the need of torque converter, the importance of electronic control and the introduce of driving mode. As the result the CVT has improved driving performance and fuel economy for current CVT and 4 speed automatic transmission. 13 figs., 2 tabs.

  2. An evaluation of a weightlifting belt and back injury prevention training class for airline baggage handlers.

    Science.gov (United States)

    Reddell, C R; Congleton, J J; Dale Huchingson, R; Montgomery, J F

    1992-10-01

    This study evaluated the efficacy of a commercially available weightlifting belt in relation to reduction of lumbar injury incident rate and severity of injuries over an 8-month period. The study used 642 baggage handlers working for a major airline company as participants. Four treatment groups were randomly selected: a group receiving the belt only, a group receiving a 1 h training class only, a group receiving both a belt and a 1 h training class, and a control group receiving nothing. Two treatment groups were added which contained participants who discontinued use of the belt prior to the end of an 8-month study period. Results indicated that there were no significant differences for total lumbar injury incident rate, restricted workday case injury incident rate, lost workdays and restricted workdays rate, and worker's compensation rates. There was, however, a marginal significant difference for lost workday case injury incident rate. Groups with participants who wore the belt for a while then discontinued its use had a higher lost day case injury incident rate than did either the group receiving training only or the control group. Compliance was an overriding factor as the belt questionnaire response indicated that 58% of participants in the belt groups discontinued use of the belt before the end of 8 months. Comments made on the survey forms indicated that the belt was too hot. Similarly, comments suggested that the belt rubbed, pinched, and bruised ribs. Based on these results, the weightlifting belt used for this study cannot be recommended for use in aid of lifting during daily work activities of baggage handlers. Results indicate that use of the belts may, in fact, increase the risk of injury when not wearing a belt following a period of wearing a belt. As industries are experimenting with the use of belts, it is recommended that great care be taken in any further evaluation and close attention directed towards injuries which occur when not wearing the

  3. Carbonate hosted gold deposit in Tasmania, Australia

    International Nuclear Information System (INIS)

    Abadi, M.H.

    1999-01-01

    Full text: This study uses elemental and isotopic composition of carbonates associated with gold from Henty and Beaconsfield in Tasmania, Australia, to illustrate source of gold-bearing fluids, salinity, temperature and dissolution and reprecipitation of carbonate. The Beaconsfield and Henty gold mines are located in northern and western Tasmania respectively. Gold mineralisation in Beaconsfield occurs within the quartz-carbonate Tasmania Reef (Lower to Middle Palaeozoic sequence, Hills, 1998). The Henty gold mine is located at the base of the Cambrian Tyndall Group (volcano-sedimentary succession, White and McPhie, 1996) close to Henty Fault. Gold in carbonate samples from Henty ranges from 7.7 to 9360 ppm and in Beaconsfield ranges from 0.01 to 434 ppm. The amount of carbonate in samples from Henty and Beaconsfield gold mines varies from approximately 24 to 99.8%. Bivariate plot of Ca relative to total amounts of Mg, Fe and Mn illustrates that the major carbonate minerals at Beaconsfield and Henty gold mines are magnesian ankerite and calcite. The difference in carbonate mineralogy, at Henty and Beaconsfield gold mines, is attributed to the composition of fluids responsible for carbonate alteration. Gold and magnesium in Beaconsfield ankerite are derived from the leaching of Cambrian ultramafic rocks during the Devonian by the passage of meteoric fluids through tectonically affected Ordovician carbonates (Rao and Adabi, 1999). The total concentration of Fe and Mn are low (0.5 to 2%) in Henty and high (1 to 17.5%) in Beaconsfield ankerite, possibly due to oxidising conditions at Henty and reducing conditions at Beaconsfield gold mines during gold mineralisation. Variation of Sr values between Beaconsfield ankerite and Henty calcite is related to dissolution of limestone that increase Sr concentrations in gold mineralising fluids. Na values in both Beaconsfield (20 to 1100 ppm) and Henty carbonates (25 to 1650 ppm) suggest low salinity fluids responsible for gold

  4. Study on Fuzzy Comprehensive Evaluation Model for the Safety of Mine Belt Conveyor

    Directory of Open Access Journals (Sweden)

    Gong Xiaoyan

    2017-01-01

    Full Text Available To improve the situation of the frequent failures of mine belt conveyor during operation, a model was used to evaluate the safety of mine belt conveyor. Based on the foundation of collecting and analyzing a large quantity of fault information of belt conveyor in the nationwide coal mine, the fault tree model of belt conveyor has been built, then the safety evaluation index system was established by analyzing and removing some secondary indicators. Furthermore, the weighted value of safety evaluation indexs was determined by analytic hierarchy process(AHP, and the single factor fuzzy evaluation matrix was constructed by experts grading method. Additionally, the model was applied in evaluating the security of belt conveyor in Nanliang coal mine. The results shows the security level is recognized to the “general”, which means that this model can be adopted widely in evaluating the safety of mine belt conveyor.

  5. Number of conveyor belts optimization regarding to its type and logistical parameters in mining industry

    Directory of Open Access Journals (Sweden)

    Dušan Malindžák

    2008-12-01

    Full Text Available Material transportation by belt conveyers is widely used in many industrial branches including mining plants. Belt conveyingdevelopment during the last year was oriented mainly on construction of belts. The consequence of this is the improvement of itsmanufacture qualities bringing down the costs for their exchange and maintenance.Despite the fact that there are some theoreticalcalculations based on a standards it is common in the industry that the belt is not properly selected or it is overdesigned or number of itstypes is too large what can lead to increased costs for its storage. The paper describes the optimization of number of belt types in miningcompany SIDERIT, s. r. o. Nižná Slaná by the method of modernization and unification of belts under practical skills and projectingbased on theoretical calculations.

  6. Start-up of belt conveyors used for haulage of large lumps under difficult climatic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Drobny, J

    1979-01-01

    Investigations are discussed carried out by the Research and Development Center for Brown Coal in Most, Czechoslovakia into effects of climate, weather and mass of coal lumps on reliability of belt conveyors in surface mines. Dirt buildup on the driving drums reduces friction and increases belt sliding hazards. Belt wear increases. Driving drum diameter, increased by the buildup, negatively influences load distribution among the electric motors of the drive system. In extreme cases belt wear and irregular load distribution cause belt failures. Methods for buildup removal used in Czechoslovakia and methods for protection of the return side of a conveyor are described. Effects of large mass of coal lumps and ice buildup on large lumps on the risk of belt damage (cuts, punctures etc,) are discussed. Recommendations for design of coal transfer points are made. 2 refs.

  7. Worth their weight in gold

    International Nuclear Information System (INIS)

    Van Ryssen, E.

    1986-01-01

    A radiotherapeutic method of treating tumours in, on and around the eye, developed and improved over more than a decade of research at the University of Cape Town's Medical School and at the city's Groote Schuur Hospital, has won worldwide recognition. A problem when irradiating eye tumours is that the rays can damage surrounding tissues. Professor Sealy's team overcome this problem by using tailor-made gold or stainless steel shields moulded indiridually to fit the curve of the eyeball of each patient. Depending on the location of the tumour, small radioactive seeds of iodine 125 are placed on the inner or outer curve of the shield in such a way that their rays are confined to the desired location. The number and position of the seeds is worked out to give the desired dose of radiation

  8. Gold nanoparticles: generation and characterization

    International Nuclear Information System (INIS)

    Dey, G.R.

    2013-07-01

    In this presentation we report the reduction of Au 3+ through chemical and free radical (e solv - ) reactions both in non-aqueous and aqueous media. In chemical reduction, the spectral nature in ascorbic acid (AA) and citric acid (CA) systems was different. The band intensity of gold nanoparticles was lower in AA system. While in free radical reaction, the yield of nanoparticles was pure i.e. free from excess reactants. Under the study 60-200 nm size nanoparticles were generated, which are inert to oxygen. Using pulse radiolysis technique, the initial rate for e solv - reaction with Au 3+ was determined to be 7.6 x 10 9 M -1 s -1 . (author)

  9. Extinction Coefficient of Gold Nanostars.

    Science.gov (United States)

    de Puig, Helena; Tam, Justina O; Yen, Chun-Wan; Gehrke, Lee; Hamad-Schifferli, Kimberly

    2015-07-30

    Gold nanostars (NStars) are highly attractive for biological applications due to their surface chemistry, facile synthesis and optical properties. Here, we synthesize NStars in HEPES buffer at different HEPES/Au ratios, producing NStars of different sizes and shapes, and therefore varying optical properties. We measure the extinction coefficient of the synthesized NStars at their maximum surface plasmon resonances (SPR), which range from 5.7 × 10 8 to 26.8 × 10 8 M -1 cm -1 . Measured values correlate with those obtained from theoretical models of the NStars using the discrete dipole approximation (DDA), which we use to simulate the extinction spectra of the nanostars. Finally, because NStars are typically used in biological applications, we conjugate DNA and antibodies to the NStars and calculate the footprint of the bound biomolecules.

  10. Intensification Behavior of Mercury Ions on Gold Cyanide Leaching

    Directory of Open Access Journals (Sweden)

    Qiang Zhong

    2018-01-01

    Full Text Available Cyanidation is the main method used to extract gold from gold raw materials; however, a serious problem with this method is the low leaching rate. In order to improve gold leaching, the intensification behavior of mercury ions on gold cyanide leaching, for two types of materials, sulphide gold concentrate and oxide gold ore, was investigated. The results showed that mercury ions, with only a 10−5 M dosage, could significantly intensify leaching and gold recovery. The dissolution behavior of gold plate was also intensified by 10−5 M mercury ions. Microstructure analysis showed that mercury ions intensified the cyanidation corrosion of the gold surface, resulting in a loose structure, where a large number of deep ravines and raised particles were evident across the whole gold surface. The loose structure added contact surface between the gold and cyanide, and accelerated gold dissolution. Moreover, mercury ions obstructed the formation of insoluble products, such as AuCN, Au(OHCN, and Au(OHx, that lead to a passivation membrane on the gold surface, reducing contact between the gold and cyanide. These effects, brought about by mercury ions, change the structure and product of the gold surface during gold cyanidation and promote gold leaching.

  11. Enrichment of Gold in Antimony Matte by Direct Smelting of Refractory Gold Concentrate

    Science.gov (United States)

    Yang, Tianzu; Xie, Boyi; Liu, Weifeng; Zhang, Duchao; Chen, Lin

    2018-04-01

    Conventional cyanidation technology achieves low gold recovery when used to process refractory gold concentrate. Based on the geochemical characteristics of gold deposit mineralization, a new method is proposed herein for gold enrichment in antimony matte by smelting of refractory gold concentrate. The effects of the FeO/SiO2 and CaO/SiO2 ratios, smelting temperature, and smelting time on the gold recovery were investigated in detail. The optimum conditions were determined to be FeO/SiO2 ratio of 1.2, CaO/SiO2 ratio of 0.4, smelting temperature of 1200°C, and smelting time of 45 min. The gold content in antimony matte and smelting slag was 96.68 and 1.13 g/t, respectively. The gold, antimony, and arsenic recovery was 97.72%, 26.89%, and 6.56%, respectively, with most of the antimony and arsenic volatilized into dust. Mineral liberation analyzer results showed that the antimony matte mainly consisted of FeS and FeO, with three phases, viz. FeAs, SbAs, and AuSb, embedded between them, indicating that gold was easily enriched with antimony and arsenic during smelting of refractory gold concentrate.

  12. Coal-gold agglomeration: an alternative separation process in gold recovery

    Energy Technology Data Exchange (ETDEWEB)

    Akcil, A.; Wu, X.Q.; Aksay, E.K. [Suleyman Demirel University, Isparta (Turkey). Dept. of Mining Engineering

    2009-07-01

    Considering the increasing environmental concerns and the potential for small gold deposits to be exploited in the future, the uses of environmentally friendly processes are essential. Recent developments point to the potential for greatly increased plant performance through a separation process that combines the cyanide and flotation processes. In addition, this kind of alternative treatment processes to the traditional gold recovery processes may reduce the environmental risks of present small-scale gold mining. Gold recovery processes that applied to different types of gold bearing ore deposits show that the type of deposits plays an important role for the selection of mineral processing technologies in the production of gold and other precious metals. In the last 25 years, different alternative processes have been investigated on gold deposits located in areas where environmental issues are a great concern. In 1988, gold particles were first recovered by successful pilot trial of coal-gold agglomeration (CGA) process in Australia. The current paper reviews the importance of CGA in the production of gold ore and identifies areas for further development work.

  13. Gold Leaching Characteristics and Intensification of a High S and As-Bearing Gold Concentrate

    Science.gov (United States)

    Yang, Yong-bin; Liu, Xiao-liang; Jiang, Tao; Li, Qian; Xu, Bin; Zhang, Yan

    Some high sulfur and arsenic-bearing gold concentrate has a gold leaching rate less than 80% by oxidation roasting-pickling-cyanidation process. The characteristics and intensification of gold leaching were studied systemically. By combining chemical composition and phase analysis, the low gold leaching rate was found to lie in the capsulation of gold by iron-containing phases including iron oxides, arsenopyrite and pyrite. 96.66% of gold in the industrial leaching residue was capsulated and 95.88% of the capsulated turned out to be in the iron-containing phases. The results of laboratory pickling-cyanidation experiments on the calcine and industrial leaching residue presented further demonstration for the fact that gold capsulated in the iron-containing phases was hard to be leached. However, the gold cyanide leaching rate of calcine could be raised over 95% by a reduction roasting-pickling pretreatment which played such a significant role in exposing the capsulated gold that gold leaching was intensified remarkably.

  14. Enrichment of Gold in Antimony Matte by Direct Smelting of Refractory Gold Concentrate

    Science.gov (United States)

    Yang, Tianzu; Xie, Boyi; Liu, Weifeng; Zhang, Duchao; Chen, Lin

    2018-06-01

    Conventional cyanidation technology achieves low gold recovery when used to process refractory gold concentrate. Based on the geochemical characteristics of gold deposit mineralization, a new method is proposed herein for gold enrichment in antimony matte by smelting of refractory gold concentrate. The effects of the FeO/SiO2 and CaO/SiO2 ratios, smelting temperature, and smelting time on the gold recovery were investigated in detail. The optimum conditions were determined to be FeO/SiO2 ratio of 1.2, CaO/SiO2 ratio of 0.4, smelting temperature of 1200°C, and smelting time of 45 min. The gold content in antimony matte and smelting slag was 96.68 and 1.13 g/t, respectively. The gold, antimony, and arsenic recovery was 97.72%, 26.89%, and 6.56%, respectively, with most of the antimony and arsenic volatilized into dust. Mineral liberation analyzer results showed that the antimony matte mainly consisted of FeS and FeO, with three phases, viz. FeAs, SbAs, and AuSb, embedded between them, indicating that gold was easily enriched with antimony and arsenic during smelting of refractory gold concentrate.

  15. [Use of seat belts and mobile phone while driving in Florence: trend from 2005 to 2009].

    Science.gov (United States)

    Lorini, Chiara; Pellegrino, Elettra; Mannocci, Federico; Allodi, Guendalina; Indiani, Laura; Mersi, Anna; Petrioli, Giuseppe; Santini, Maria Grazia; Garofalo, Giorgio; Bonaccorsi, Guglielmo

    2012-01-01

    to evaluate the trend over time of the use of seat belts by drivers and passengers of cars and vans and the use of hand held mobile phone while driving in Florence from 2005 to 2009. DESIGN, SETTING AND PARTICIPANTS AND MAIN OUTCOME MEASURES: direct observations (58,773 vehicles) have been conducted to detect the use of seat belts by occupants of cars and vans, and the use of mobile phone while driving. It has been carried out correlation analysis between the use of the seat belt by occupants of vehicles and between the simultaneous use of this device and mobile phone while driving.Moreover, it has been carried out time series analysis (ARIMA Box Jenkins) of in the prevalence of the use of seat belts by occupants of vehicles observed, of mobile phone by drivers and the trend of the risk to drive using the mobile phone with unfastened seat belt rather than to drive using the mobile phone with fastened seat belt. seat belts were used on average by 75.7% of drivers, 75.5% of front passengers and 25.1% of rear passengers. The average mobile phone use while driving was 4.5%. Drivers most frequently fasten seat belt if front passengers use it and while they do not use mobile phone. The use of seat belts by drivers and front passengers has not changed over time, whereas the use of mobile phone while driving has significantly increased. The prevalence of using mobile phone with unfastened seat belt rather than to use it with fastened seat belt while driving has significantly decreased over the years, indicating an increase in the use of mobile phone, especially among those who fasten the seat belt. it is necessary to plan and realize stronger interventions in the whole area.

  16. Measurement and monitoring of electrocardiogram belt tension in premature infants for assessment of respiratory function

    OpenAIRE

    Hegyi Thomas; Hiatt Mark; Ciaccio Edward J; Drzewiecki Gary M

    2007-01-01

    Abstract Background Monitoring of the electrocardiogram (ECG) in premature infants with conventional adhesive-backed electrodes can harm their sensitive skin. Use of an electrode belt prevents skin irritation, but the effect of belt pressure on respiratory function is unknown. A strain gauge sensor is described which measures applied belt tension. Method The device frame was comprised of an aluminum housing and slide to minimize the device weight. Velcro tabs connected housing and slide to op...

  17. Effects of a Belt on Intra-Abdominal Pressure during Weight Lifting.

    Science.gov (United States)

    1988-03-01

    potentially injurious b compressive forces on spinal discs during lifting. To investigate the effects of a standard lifting belt on lAP and lifting mechanics... injurious compressive forces on spinal discs during lifting. To investigate the effects of a standard lifting belt on IAP and lifting ! mechanics... weightlifting (7,9). Both olympic and power lifters have used lifting belts for many years, yet virtually no research has been reported which examines

  18. Race, belief in destiny, and seat belt usage: a pilot study.

    Science.gov (United States)

    Colón, I

    1992-01-01

    A survey of 1063 individuals found that when belief in destiny was statistically controlled, differences in seat belt use by race disappeared. Thus, racial differences in seat belt use are statistically accounted for and might be explained by belief in destiny. Efforts to increase seat belt use should target minority groups rather than include them in broadbrush programs. Further, these efforts should take into account this important difference in motivation. PMID:1585969

  19. The giant Jiaodong gold province: The key to a unified model for orogenic gold deposits?

    Directory of Open Access Journals (Sweden)

    David I. Groves

    2016-05-01

    Full Text Available Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits, with the exception of Carlin-type deposits and rare intrusion-related gold systems, there has been continuing debate on their genesis. Early syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly unacceptable. Magmatic-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially – associated granitic intrusions and inconsistent temporal relationships. The most plausible, and widely accepted, models involve metamorphic fluids, but the source of these fluids is hotly debated. Sources within deeper segments of the supracrustal successions hosting the deposits, the underlying continental crust, and subducted oceanic lithosphere and its overlying sediment wedge all have their proponents. The orogenic gold deposits of the giant Jiaodong gold province of China, in the delaminated North China Craton, contain ca. 120 Ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold mineralization. The only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package, or the associated mantle wedge. This could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks: basaltic rocks in the Precambrian and sedimentary rocks in the Phanerozoic. Alternatively, if a holistic view is taken, Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth history. The latter model satisfies all geological, geochronological, isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release, like many

  20. Gold nanoparticles produced in a microalga

    International Nuclear Information System (INIS)

    Luangpipat, Tiyaporn; Beattie, Isabel R.; Chisti, Yusuf; Haverkamp, Richard G.

    2011-01-01

    An efficient biological route to production of gold nanoparticles which allows the nanoparticles to be easily recovered remains elusive. Live cells of the green microalga Chlorella vulgaris were incubated with a solution of gold chloride and harvested by centrifugation. Nanoparticles inside intact cells were identified by transmission electron microscopy and confirmed to be metallic gold by synchrotron based X-ray powder diffraction and X-ray absorption spectroscopy. These intracellular gold nanoparticles were 40–60 nm in diameter. At a concentration of 1.4% Au in the alga, a better than 97% recovery of the gold from solution was achieved. A maximum of 4.2% Au in the alga was obtained. Exposure of C. vulgaris to solutions containing dissolved salts of palladium, ruthenium, and rhodium also resulted in the production of the corresponding nanoparticles within the cells. These were surmised to be also metallic, but were produced at a much lower intracellular concentration than achieved with gold. Iridium was apparently toxic to the alga. No nanoparticles were observed using platinum solutions. C. vulgaris provides a possible route to large scale production of gold nanoparticles.

  1. NUCLEATION STUDIES OF GOLD ON CARBON ELECTRODES

    Directory of Open Access Journals (Sweden)

    S. SOBRI

    2008-04-01

    Full Text Available Interest has grown in developing non-toxic electrolytes for gold electrodeposition to replace the conventional cyanide-based bath for long term sustainability of gold electroplating. A solution containing thiosulphate and sulphite has been developed specially for microelectronics applications. However, at the end of the electrodeposition process, the spent electrolyte can contain a significant amount of gold in solution. This study has been initiated to investigate the feasibility of gold recovery from a spent thiosulphate-sulphite electrolyte. We have used flat-plate glassy carbon and graphite electrodes to study the mechanism of nucleation and crystal growth of gold deposition from the spent electrolyte. It was found that at the early stages of reduction process, the deposition of gold on glassy carbon exhibits an instantaneous nucleation of non-overlapping particles. At longer times, the particles begin to overlap and the deposition follows a classic progressive nucleation phenomenon. On the other hand, deposition of gold on graphite does not follow the classical nucleation phenomena.

  2. Nature vs. nurture: gold perpetuates "stemness".

    Science.gov (United States)

    Paul, Willi; Sharma, Chandra P; Deb, Kaushik Dilip

    2011-01-01

    Adult tissues contain quiescent reservoirs of multipotent somatic stem cells and pluripotent embryonic-like stem cells (ELSCs). Credited with regenerative properties gold is used across both -contemporary and -ancient medicines. Here, we show that gold exerted these effects by enhancing the pool of pluripotent ELSC while improving their stemness. We used hESCs as an in-vitro model to understand if gold could enhance self-renewal and pluripotency. Swarna-bhasma (SB), an ancient Indian gold microparticulate (41.1 nm), preparation, reduced spontaneous-differentiation, improved self-renewal, pluripotency and proliferation of hESCs. Colloidal gold-nanoparticles (GNP) (15.59 nm) were tested to confirm that the observations were attributable to nanoparticulate-gold. SB and GNP exposure: maintained -stemness, -karyotypic stability, enhanced pluripotency till day-12, increased average colony-sizes, and reduced the number of autonomously-derived differentiated FGFR1 positive fibroblast-niche-cells/colony. Particulate-gold induced upregulation of FGFR1 and IGF2 expression, and decrease in IGF1 secretion indicates IGF1/2 mediated support for enhanced pluripotency and self-renewal in hESCs.

  3. Urban artisanal gold shops and mercury emissions

    International Nuclear Information System (INIS)

    Cordy, P.; Veiga, M.; Carrasco, V.H.G.

    2008-01-01

    Artisanal miners in developing countries use mercury amalgamation processes to extract gold. The amalgams are then refined before being sold on to urban gold shops. The amalgams can often contain between 2 to 40 per cent mercury. Unburned amalgams are also often sold directly to gold shops. There are serious health risks for shop employees and nearby populations when the gold is melted and further purified. Studies have shown that mercury concentrations in the ambient air of gold shops often exceeds World Health Organization (WHO) limits by an order of magnitude or more. This study examined the practices and technologies used to refine gold in Latin America and Indonesia. The study compared and contrasted various refining methods and their resulting mercury emissions. Methods of reducing mercury emissions were also investigated, including a filtration system designed to capture 80 per cent of mercury emissions. Barriers to implementing mercury emissions reduction plans were also investigated. It was concluded that the design of urban gold shops must include condensers, fume hoods, and efficient mercury capture systems. 15 refs

  4. Phytomining for Artisanal Gold Mine Tailings Management

    Directory of Open Access Journals (Sweden)

    Baiq Dewi Krisnayanti

    2016-08-01

    Full Text Available Mine tailings are generally disposed of by artisanal and small scale gold miners in poorly constructed containment areas and this leads to environmental risk. Gold phytomining could be a possible option for tailings management at artisanal and small-scale gold mining (ASGM locations where plants accumulate residual gold in their above ground biomass. The value of metal recovered from plants could offset some of the costs of environmental management. Getting gold into plants has been repeatedly demonstrated by many research groups; however, a simple working technology to get gold out of plants is less well described. A field experiment to assess the relevance of the technology to artisanal miners was conducted in Central Lombok, Indonesia between April and June 2015. Tobacco was planted in cyanidation tailings (1 mg/kg gold and grown for 2.5 months before the entire plot area was irrigated with NaCN to induce metal uptake. Biomass was then harvested (100 kg, air dried, and ashed by miners in equipment currently used to ash activated carbon at the end of a cyanide leach circuit. Borax and silver as a collector metal were added to the tobacco ash and smelted at high temperature to extract metals from the ash. The mass of the final bullion (39 g was greater than the mass of silver used as a collector (31 g, indicating recovery of metals from the biomass through the smelt process. The gold yield of this trial was low (1.2 mg/kg dry weight biomass concentration, indicating that considerable work must still be done to optimise valuable metal recovery by plants at the field scale. However, the described method to process the biomass was technically feasible, and represents a valid technique that artisanal and small-scale gold miners are willing to adopt if the economic case is good.

  5. Electrochemical Oxidation of Glycerol Using Gold Electrode

    International Nuclear Information System (INIS)

    Mohamed Rozali Othman; Amirah Ahmad

    2015-01-01

    Cyclic voltammetry, potential linear V and chronocuolometry methods were carried out to gain electrochemical behavior of glycerol at a gold electrode. Potassium hydroxide and sulfuric acid were chosen to be the electrolyte for the electro-oxidation of this organic compound. Besides gold plate electrode, gold composite electrode (Au-PVC) was also used as the working electrode. The Au-PVC composite electrode was characterized by Scanning Electron Microscopy (SEM) to determine its morphological aspects before and after used in electrochemical oxidation of glycerol. In alkaline solution, the adsorption of hydroxide species onto the surface of both gold plate and composite Au-PVC electrodes occurs at potential around 500 mV vs SCE. However, at gold plate electrode, there was a small, broad peak before the drastic escalation of current densities which indicates the charge transfer of the chemisorbed OH - anion. In acidic media, the gold oxide was formed after potential 1.0 V. From the cyclic voltammogram glycerol undergo oxidation twice in potassium hydroxide at gold plate and Au-PVC composite electrodes, while in sulfuric acid, oxidation reaction happened once for glycerol on the gold plate electrode. Overall, electrochemical oxidation of glycerol was more effective in alkaline media. Tafel graph which plotted from potential linear V method shows that Au-PVC composite electrode is better than gold plate electrode for the electro-oxidation of glycerol in alkaline solution. Electrochemical oxidation of glycerol products as analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) produced several carboxylic acids and phenolic compounds. (author)

  6. A multi points ultrasonic detection method for material flow of belt conveyor

    Science.gov (United States)

    Zhang, Li; He, Rongjun

    2018-03-01

    For big detection error of single point ultrasonic ranging technology used in material flow detection of belt conveyor when coal distributes unevenly or is large, a material flow detection method of belt conveyor is designed based on multi points ultrasonic counter ranging technology. The method can calculate approximate sectional area of material by locating multi points on surfaces of material and belt, in order to get material flow according to running speed of belt conveyor. The test results show that the method has smaller detection error than single point ultrasonic ranging technology under the condition of big coal with uneven distribution.

  7. Study on the application of permanent magnet synchronous motors in underground belt conveyors

    Science.gov (United States)

    Ma, S. H.

    2017-12-01

    This paper analyzes and compares the advantages and disadvantages of several kinds of drive devices of belt conveyors from the angle of energy saving, and summarizes the application advantages and using problems of permanent magnet motor variable frequency drive system in belt conveyors. An example is given to demonstrate the energy saving effect of this system compared with other driving methods. This paper points out the application prospect of permanent magnet motor variable frequency drive system on belt conveyors and other large mining machines in coal mine. This paper is aimed to provide the design direction for the designer and the choice basis for the user on belt conveyor.

  8. The Sino-American belt study: nickel and cobalt exposure, epidemiology, and clinical considerations.

    Science.gov (United States)

    Hamann, Dathan; Hamann, Carsten; Li, Lin-Feng; Xiang, Hailian; Hamann, Kylin; Maibach, Howard; Taylor, James S; Thyssen, Jacob P

    2012-01-01

    Nickel and cobalt are common causes of metal allergy. The objective of this study was to investigate nickel and cobalt exposure in belt buckles by testing 701 belts purchased in China and the United States and to consider the prevalence of nickel allergy and its relevance among Chinese patients. Seven hundred one belt buckles purchased in China and the United States were tested for nickel and cobalt release. Six hundred thirty-one Chinese patients with suspected allergic contact dermatitis were patch tested and interviewed to determine clinical relevance of results. The Chinese and American literature was reviewed to investigate trends in nickel prevalence over the past decades. Sixty percent (n = 219) of belts purchased in China (n = 365) released nickel, and 0.5% (n = 2) released cobalt; 55.7% (n = 187) in the United States (n = 336) released nickel, and 0.9% (n = 3) released cobalt. Belt dermatitis was a significant clinical finding in 34.8% of Chinese nickel-allergic patients. Literature review suggests increasing nickel allergy prevalence in the United States and China. Metallic belt buckles are an important source of nickel exposure to consumers. Belts from lowest socioeconomic vendors were more likely to release nickel. Belts with silver color and dark metallic color were more likely to release nickel and cobalt, respectively. Clinical findings show belt dermatitis in China to be a problem.

  9. The behavioral impact of an advertising campaign to promote safety belt use.

    Science.gov (United States)

    Cope, J G; Moy, S S; Grossnickle, W F

    1988-01-01

    Safety belt use was observed at one restaurant during McDonald's "Make It Click" promotional campaign. Following baseline, the program was monitored without intervention. During the final 2 weeks of the campaign an incentive strategy was added providing a large soft drink contingent on safety belt use. Safety belt use did not change from baseline levels before the incentive phase. The rate of belt use increased under contingent reward and declined during follow-up. The effects of a verbal prompt could not be assessed because of the almost nonexistent use of the "Make It Click" stickers throughout the study.

  10. The evolution of Saturn's radiation belts modulated by changes in radial diffusion

    Science.gov (United States)

    Kollmann, P.; Roussos, E.; Kotova, A.; Paranicas, C.; Krupp, N.

    2017-12-01

    Globally magnetized planets, such as the Earth1 and Saturn2, are surrounded by radiation belts of protons and electrons with kinetic energies well into the million electronvolt range. The Earth's proton belt is supplied locally from galactic cosmic rays interacting with the atmosphere3, as well as from slow inward radial transport4. Its intensity shows a relationship with the solar cycle4,5 and abrupt dropouts due to geomagnetic storms6,7. Saturn's proton belts are simpler than the Earth's because cosmic rays are the principal source of energetic protons8 with virtually no contribution from inward transport, and these belts can therefore act as a prototype to understand more complex radiation belts. However, the time dependence of Saturn's proton belts had not been observed over sufficiently long timescales to test the driving mechanisms unambiguously. Here we analyse the evolution of Saturn's proton belts over a solar cycle using in-situ measurements from the Cassini Saturn orbiter and a numerical model. We find that the intensity in Saturn's proton radiation belts usually rises over time, interrupted by periods that last over a year for which the intensity is gradually dropping. These observations are inconsistent with predictions based on a modulation in the cosmic-ray source, as could be expected4,9 based on the evolution of the Earth's proton belts. We demonstrate that Saturn's intensity dropouts result instead from losses due to abrupt changes in magnetospheric radial diffusion.

  11. Synthesis of gold nanoparticles with graphene oxide.

    Science.gov (United States)

    Wang, Wenshuo; He, Dawei; Zhang, Xiqing; Duan, Jiahua; Wu, Hongpeng; Xu, Haiteng; Wang, Yongsheng

    2014-05-01

    Single sheets of functionalized graphene oxide are derived through chemical exfoliation of natural flake graphite. We present an effective synthetic method of graphene-gold nanoparticles hybrid nanocomposites. AFM (Atomic Force Microscope) was used to measure the thickness of the individual GO nanosheet. FTIR (Fourier transform infrared) spectroscopy was used to verify the attachment of oxygen functionalities on the surface of graphene oxide. TEM (Transmission Electron Microscope) data revealed the average diameters of the gold colloids and characterized the composite particles situation. Absorption spectroscopy showed that before and after synthesis the gold particle size did not change. Our studies indicate that the hybrid is potential substrates for catalysts and biosensors.

  12. Biosynthesis of Gold Nanoparticles Using Pseudomonas Aeruginosa

    International Nuclear Information System (INIS)

    Abd El-Aziz, M.; Badr, Y.; Mahmoud, M. A.

    2007-01-01

    Pseudomonas aeruginosa were used for extracellular biosynthesis of gold nanoparticles (Au NPs). Consequently, Au NPs were formed due to reduction of gold ion by bacterial cell supernatant of P. aeruginos ATCC 90271, P. aeruginos (2) and P. aeruginos (1). The UV-Vis. and fluorescence spectra of the bacterial as well as chemical prepared Au NPs were recorded. Transmission electron microscopy (TEM) micrograph showed the formation of well-dispersed gold nanoparticles in the range of 15-30 nm. The process of reduction being extracellular and may lead to the development of an easy bioprocess for synthesis of Au NPs

  13. The giant Kalgoorlie Gold Field revisited

    Directory of Open Access Journals (Sweden)

    Noreen Mary Vielreicher

    2016-05-01

    Direct timing constraints on gold mineralization indicate that Fimiston- and Mt Charlotte-style mineralization formed within a relative short period of time around 2.64 Ga, and, as such, support a model of progressive deformation of a rheologically heterogeneous rock package late in the structural history. Fluid characteristics, combined with the structural, metamorphic and absolute timing, support description of gold mineralization at the Golden Mile as orogenic and mesozonal, and this allows direct correlation with orogenic gold deposits worldwide, which classically formed during accretion along convergent margins throughout Earth history.

  14. Nondestructive analysis of the gold quarter liras

    International Nuclear Information System (INIS)

    Cakir, C.; Guerol, A.; Demir, L.; Sahin, Y.

    2009-01-01

    In this study, we have prepared seven Au-Cu standards in the concentration range of 18-24 (as carat) for nondestructive control of gold quarter liras. Some calibration curves for quantitative analysis of Au in the gold quarter liras that commercially present in Turkey have been plotted using these standard samples. The characteristic X-rays of Au and Cu emitted from these standard samples and the test sample with known composition are recorded by using a Ge(Li) detector. These calibration curves provide a nondestructive analysis of gold quarter liras with the uncertainties about 1.18%. (author)

  15. Refractory concentrate gold leaching: Cyanide vs. bromine

    Science.gov (United States)

    Dadgar, Ahmad

    1989-12-01

    Gold extraction, recovery and economics for two refractory concentrates were investigated using cyanide and bromine reagents. Gold extractions for cyanide leaching (24-48 hours) and bromine leaching (six hours) were the same and ranged from 94 to 96%. Gold recoveries from bromine pregnant solutions using carbon adsorption, ion exchange, solvent extraction, and zinc and aluminum precipitation methods were better than 99.9%. A preliminary economic analysis indicates that chemical costs for cyanidation and bromine process are 11.70 and 11.60 respectively, per tonne of calcine processed.

  16. Gold's monetary roll will be strengthened - Plumbridge

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Delivering his Presidential address at the Chamber's annual general meeting, Mr Plumbridge said the gold market would enter a new phase and listed seven reasons why gold's monetary role would be strengthened. There was a dramatic increase in the demand for gold jewellery. He also forecasted that South African uranium production would again attain its former peak annual production of about 6000t. There is an essential need for a sustained growth in nuclear power and the prospects for uranium mining industry remain encouraging

  17. Gold nanoparticles extraction from dielectric scattering background

    Science.gov (United States)

    Hong, Xin; Wang, Jingxin

    2014-11-01

    The unique advantages such as brightness, non-photobleaching, good bio-compatibility make gold nanoparticles desirable labels and play important roles in biotech and related research and applications. Distinguishing gold nanoparticles from other dielectric scattering particles is of more importance, especially in bio-tracing and imaging. The enhancement image results from the localized surface plasmon resonance associated with gold nanopartilces makes themselves distinguishable from other dielectric particles, based on which, we propose a dual-wavelength detection method by employing a high sensitive cross-polarization microscopy.

  18. Gold Photoluminescence: Wavelength and Polarization Engineering

    DEFF Research Database (Denmark)

    Andersen, Sebastian Kim Hjælm; Pors, Anders Lambertus; Bozhevolnyi, Sergey I.

    2015-01-01

    We demonstrate engineering of the spectral content and polarization of photoluminescence (PL) from arrayed gold nanoparticles atop a subwavelength-thin dielectric spacer and optically-thick gold film, a configuration that supports gap-surface plasmon resonances (GSPRs). Choice of shapes...... and dimensions of gold nanoparticles influences the GSPR wavelength and polarization characteristics, thereby allowing us to enhance and spectrally mold the plasmon-assisted PL while simultaneously controlling its polarization. In order to understand the underlying physics behind the plasmon-enhanced PL, we...

  19. Nuclear analyses of the Pietroasa gold hoard

    International Nuclear Information System (INIS)

    Cojocaru, V.; Besliu, C.

    1999-01-01

    By means of nuclear analyses the concentrations of Au, Ag, Cu, Ir, Os, Pt, Co and Hg were measured in the 12 artifacts of the gold hoard discovered in 1837 at Pietroasa, Buzau country in Romania. The concentrations of the first four elements were used to compare different stylistic groups assumed by historians. Comparisons with gold nuggets from the old Dacian territory and gold Roman imperial coins were also made. A good agreement was found with the oldest hypothesis which considers that the hoard is represented by three styles appropriated mainly by the Goths. (author)

  20. TRIGGERING SUBLIMATION-DRIVEN ACTIVITY OF MAIN BELT COMETS

    Energy Technology Data Exchange (ETDEWEB)

    Haghighipour, N. [Institute for Astronomy, University of Hawaii-Manoa, Honolulu, HI 96825 (United States); Maindl, T. I.; Dvorak, R. [Department of Astrophysics, University of Vienna, Türkenschanzstrasse 17, A-1180 Vienna (Austria); Schäfer, C. [Institut für Astronomie und Astrophysik, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 10, D-72076 Tübingen (Germany); Speith, R., E-mail: nader@ifa.hawaii.edu [Physikalisches Institut, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen (Germany)

    2016-10-10

    It has been suggested that the comet-like activity of main belt comets (MBCs) is due to the sublimation of sub-surface water–ice that has been exposed as a result of their surfaces being impacted by meter-sized bodies. We have examined the viability of this scenario by simulating impacts between meter-sized and kilometer-sized objects using a smooth particle hydrodynamics approach. Simulations have been carried out for different values of the impact velocity and impact angle, as well as different target material and water-mass fractions. Results indicate that for the range of impact velocities corresponding to those in the asteroid belt, the depth of an impact crater is slightly larger than 10 m, suggesting that if the activation of MBCs is due to the sublimation of sub-surface water–ice, this ice has to exist no deeper than a few meters from the surface. Results also show that ice exposure occurs in the bottom and on the interior surface of impact craters, as well as on the surface of the target where some of the ejected icy inclusions are re-accreted. While our results demonstrate that the impact scenario is indeed a viable mechanism to expose ice and trigger the activity of MBCs, they also indicate that the activity of the current MBCs is likely due to ice sublimation from multiple impact sites and/or the water contents of these objects (and other asteroids in the outer asteroid belt) is larger than the 5% that is traditionally considered in models of terrestrial planet formation, providing more ice for sublimation. We present the details of our simulations and discuss their results and implications.

  1. UNBIASED INCLINATION DISTRIBUTIONS FOR OBJECTS IN THE KUIPER BELT

    International Nuclear Information System (INIS)

    Gulbis, A. A. S.; Elliot, J. L.; Adams, E. R.; Benecchi, S. D.; Buie, M. W.; Trilling, D. E.; Wasserman, L. H.

    2010-01-01

    Using data from the Deep Ecliptic Survey (DES), we investigate the inclination distributions of objects in the Kuiper Belt. We present a derivation for observational bias removal and use this procedure to generate unbiased inclination distributions for Kuiper Belt objects (KBOs) of different DES dynamical classes, with respect to the Kuiper Belt plane. Consistent with previous results, we find that the inclination distribution for all DES KBOs is well fit by the sum of two Gaussians, or a Gaussian plus a generalized Lorentzian, multiplied by sin i. Approximately 80% of KBOs are in the high-inclination grouping. We find that Classical object inclinations are well fit by sin i multiplied by the sum of two Gaussians, with roughly even distribution between Gaussians of widths 2.0 +0.6 -0.5 0 and 8.1 +2.6 -2.1 0 . Objects in different resonances exhibit different inclination distributions. The inclinations of Scattered objects are best matched by sin i multiplied by a single Gaussian that is centered at 19.1 +3.9 -3.6 0 with a width of 6.9 +4.1 -2.7 0 . Centaur inclinations peak just below 20 0 , with one exceptionally high-inclination object near 80 0 . The currently observed inclination distribution of the Centaurs is not dissimilar to that of the Scattered Extended KBOs and Jupiter-family comets, but is significantly different from the Classical and Resonant KBOs. While the sample sizes of some dynamical classes are still small, these results should begin to serve as a critical diagnostic for models of solar system evolution.

  2. BAOBAB (Big And Outrageously Bold Asteroid Belt) Project

    Science.gov (United States)

    Mcfadden, L. A.; Thomas, C. A; Englander, J. A.; Ruesch, O.; Hosseini, S.; Goossens, S. J.; Mazarico, E. M.; Schmerr, N.

    2017-01-01

    One of the intriguing results of NASA's Dawn mission is the composition and structure of the Main Asteroid Belt's only known dwarf planet, Ceres [1]. It has a top layer of dehydrated clays and salts [2] and an icy-rocky mantle [3,4]. It is widely known that the asteroid belt failed to accrete as a planet by resonances between the Sun and Jupiter. About 20-30 asteroids >100 km diameter are probably differentiated protoplanets [5]. 1) how many more and which ones are fragments of protoplanets? 2) How many and which ones are primordial rubble piles left over from condensation of the solar nebula? 3) How would we go about gaining better and more complete characterization of the mass, interior structure and composition of the Main Belt asteroid population? 4) What is the relationship between asteroids and ocean worlds? Bulk parameters such as the mass, density, and porosity, are important to characterize the structure of any celestial body, and for asteroids in particular, they can shed light on the conditions in the early solar system. Asteroid density estimates exist but currently they are often based on assumed properties of taxonomic classes, or through astronomical survey data where interactions with asteroids are weak at best resulting in large measurement uncertainty. We only have direct density estimates from spacecraft encounters for a few asteroids at this time. Knowledge of the asteroids is significant not only to understand their role in solar system workings, but also to assess their potential as space resources, as impact hazards on Earth, or even as harboring life forms. And for the distant future, we want to know if the idea put forth in a contest sponsored by Physics Today, to surface the asteroids into highly reflecting, polished surfaces and use them as a massively segmented mirror for astrophysical exploration [6], is feasible.

  3. The size of the auroral belt during magnetic storms

    Directory of Open Access Journals (Sweden)

    N. Yokoyama

    Full Text Available Using the auroral boundary index derived from DMSP electron precipitation data and the Dst index, changes in the size of the auroral belt during magnetic storms are studied. It is found that the equatorward boundary of the belt at midnight expands equatorward, reaching its lowest latitude about one hour before Dst peaks. This time lag depends very little on storm intensity. It is also shown that during magnetic storms, the energy of the ring current quantified with Dst increases in proportion to Le–3, where Le is the L-value corresponding to the equatorward boundary of the auroral belt designated by the auroral boundary index. This means that the ring current energy is proportional to the ion energy obtained from the earthward shift of the plasma sheet under the conservation of the first adiabatic invariant. The ring current energy is also proportional to Emag, the total magnetic field energy contained in the spherical shell bounded by Le and Leq, where Leq corresponds to the quiet-time location of the auroral precipitation boundary. The ratio of the ring current energy ER to the dipole energy Emag is typically 10%. The ring current leads to magnetosphere inflation as a result of an increase in the equivalent dipole moment.

    Key words. Ionosphere (Auroral ionosphere · Magnetospheric physics (Auroral phenomena; storms and substorms

  4. Colloidal Microworms Propelling via a Cooperative Hydrodynamic Conveyor Belt.

    Science.gov (United States)

    Martinez-Pedrero, Fernando; Ortiz-Ambriz, Antonio; Pagonabarraga, Ignacio; Tierno, Pietro

    2015-09-25

    We study propulsion arising from microscopic colloidal rotors dynamically assembled and driven in a viscous fluid upon application of an elliptically polarized rotating magnetic field. Close to a confining plate, the motion of this self-assembled microscopic worm results from the cooperative flow generated by the spinning particles which act as a hydrodynamic "conveyor belt." Chains of rotors propel faster than individual ones, until reaching a saturation speed at distances where induced-flow additivity vanishes. By combining experiments and theoretical arguments, we elucidate the mechanism of motion and fully characterize the propulsion speed in terms of the field parameters.

  5. Nano-optical conveyor belt, part I: Theory.

    Science.gov (United States)

    Hansen, Paul; Zheng, Yuxin; Ryan, Jason; Hesselink, Lambertus

    2014-06-11

    We propose a method for peristaltic transport of nanoparticles using the optical force field over a nanostructured surface. Nanostructures may be designed to produce strong near-field hot spots when illuminated. The hot spots function as optical traps, separately addressable by their resonant wavelengths and polarizations. By activating closely packed traps sequentially, nanoparticles may be handed off between adjacent traps in a peristaltic fashion. A linear repeating structure of three separately addressable traps forms a "nano-optical conveyor belt"; a unit cell with four separately addressable traps permits controlled peristaltic transport in the plane. Using specifically designed activation sequences allows particle sorting.

  6. Paleomagnetic analysis of curved thrust belts reproduced by physical models

    Science.gov (United States)

    Costa, Elisabetta; Speranza, Fabio

    2003-12-01

    This paper presents a new methodology for studying the evolution of curved mountain belts by means of paleomagnetic analyses performed on analogue models. Eleven models were designed aimed at reproducing various tectonic settings in thin-skinned tectonics. Our models analyze in particular those features reported in the literature as possible causes for peculiar rotational patterns in the outermost as well as in the more internal fronts. In all the models the sedimentary cover was reproduced by frictional low-cohesion materials (sand and glass micro-beads), which detached either on frictional or on viscous layers. These latter were reproduced in the models by silicone. The sand forming the models has been previously mixed with magnetite-dominated powder. Before deformation, the models were magnetized by means of two permanent magnets generating within each model a quasi-linear magnetic field of intensity variable between 20 and 100 mT. After deformation, the models were cut into closely spaced vertical sections and sampled by means of 1×1-cm Plexiglas cylinders at several locations along curved fronts. Care was taken to collect paleomagnetic samples only within virtually undeformed thrust sheets, avoiding zones affected by pervasive shear. Afterwards, the natural remanent magnetization of these samples was measured, and alternating field demagnetization was used to isolate the principal components. The characteristic components of magnetization isolated were used to estimate the vertical-axis rotations occurring during model deformation. We find that indenters pushing into deforming belts from behind form non-rotational curved outer fronts. The more internal fronts show oroclinal-type rotations of a smaller magnitude than that expected for a perfect orocline. Lateral symmetrical obstacles in the foreland colliding with forward propagating belts produce non-rotational outer curved fronts as well, whereas in between and inside the obstacles a perfect orocline forms

  7. Distribution of erosion and deposition on the JET belt limiters

    International Nuclear Information System (INIS)

    McCracken, G.M.; Goodall, D.H.J.; Behrisch, R.; Roth, J.; Coad, J.P.; Harbour, P.; Kock, L. de; Pick, M.A.; Stangeby, P.C.

    1989-01-01

    The distribution of erosion and deposition of limiter material is of importance both for extrapolating to the next generation of fusion machines and for understanding impurity transport in the boundary layers of present day tokamaks. Erosion patterns have previously been reported for the JET discrete graphite limiters used up to 1986. We have now made measurements on the belt limiters used in 1987-88. These measurements show that although the pattern of net erosion is qualitatively similar to the earlier results the new maximum erosion (∼40μm) is reduced by about a factor 5, consistent with the larger limiter surface area. (author) 7 refs., 2 figs

  8. Spectroscopical studies of impurities in the belt pinch HECTOR

    International Nuclear Information System (INIS)

    Singethan, J.

    1981-04-01

    In this paper UV-line-intensity measurements of impurities are presented, which have been performed in the belt-pinch HECTOR. From the line-intensities impurity concentrations and information on the radiation losses is be obtained. At temperatures below 100 eV, the energy loss due to line emission of oxygen and carbon impurities is one of the most important electron energy loss mechanisms. Thus the measurement and calculation of the radiation losses is of particular relevance. Furthermore the electron temperature time dependence can be obtained by comparing the line intensity time dependence with the solution of the respective rate equations. (orig./HT) [de

  9. Roll seat belt induced injury of the duodenum.

    Science.gov (United States)

    Bergqvist, D; Hedelin, H

    1976-05-01

    A case of duodenal rupture with a roll three-point seatbelt is described. It is apparently the seventh reported case of duodenal rupture in safety belt users. A female driver fell asleep, and her car went off the road, rolling forward in a ditch, slowing slightly, and then came to a sudden stop. The rupture was unusual: on the first part of duodenum, intraperitoneal, and longitudinal. The rupture mechanism is discussed, and the deficiencies of the roll seatbelt pointed out in accidents like the one described.

  10. Reactor advantages of the belt pinch and liquid metal walls

    International Nuclear Information System (INIS)

    Kotschenreuther, M.; Manickam, J.; Menard, J.; Rappaport, H.; Zheng Linjin; Dorland, B.; Miller, R.; Turnbull, A.

    2001-01-01

    MHD stability of highly elongated tokamaks (termed a belt pinch) are considered for high bootstrap fraction cases. By employing high triangularity or indentation, and invoking wall stabilization, and β can be increased by a factor of roughly 3 by increasing κ from 2 to 4. Axisymmetric stability up to κ=4 tolerable by employing a shell which conforms more closely to the boundary than in present experiments. Engineering difficulties with a close fitting shell in a reactor environment may be overcome by employing a liquid lithium alloy shell. Rapid metal flows can lead to potentially deleterious plasma shifts and damping of the flow. (author)

  11. Geological evolution of the Neoproterozoic Bemarivo Belt, northern Madagascar

    Science.gov (United States)

    Thomas, Ronald J.; De Waele, B.; Schofield, D.I.; Goodenough, K.M.; Horstwood, M.; Tucker, R.; Bauer, W.; Annells, R.; Howard, K. J.; Walsh, G.; Rabarimanana, M.; Rafahatelo, J.-M.; Ralison, A.V.; Randriamananjara, T.

    2009-01-01

    The broadly east-west trending, Late Neoproterozoic Bemarivo Belt in northern Madagascar has been re-surveyed at 1:100 000 scale as part of a large multi-disciplinary World Bank-sponsored project. The work included acquisition of 14 U-Pb zircon dates and whole-rock major and trace element geochemical data of representative rocks. The belt has previously been modelled as a juvenile Neoproterozoic arc and our findings broadly support that model. The integrated datasets indicate that the Bemarivo Belt is separated by a major ductile shear zone into northern and southern "terranes", each with different lithostratigraphy and ages. However, both formed as Neoproterozoic arc/marginal basin assemblages that were translated southwards over the north-south trending domains of "cratonic" Madagascar, during the main collisional phase of the East African Orogeny at ca. 540 Ma. The older, southern terrane consists of a sequence of high-grade paragneisses (Sahantaha Group), which were derived from a Palaeoproterozoic source and formed a marginal sequence to the Archaean cratons to the south. These rocks are intruded by an extensive suite of arc-generated metamorphosed plutonic rocks, known as the Antsirabe Nord Suite. Four samples from this suite yielded U-Pb SHRIMP ages at ca. 750 Ma. The northern terrane consists of three groups of metamorphosed supracrustal rocks, including a possible Archaean sequence (Betsiaka Group: maximum depositional age approximately 2477 Ma) and two volcano-sedimentary sequences (high-grade Milanoa Group: maximum depositional age approximately 750 Ma; low grade Daraina Group: extrusive age = 720-740 Ma). These supracrustal rocks are intruded by another suite of arc-generated metamorphosed plutonic rocks, known as the Manambato Suite, 4 samples of which gave U-Pb SHRIMP ages between 705 and 718 Ma. Whole-rock geochemical data confirm the calc-alkaline, arc-related nature of the plutonic rocks. The volcanic rocks of the Daraina and Milanoa groups also

  12. Examining Relativistic Electron Loss in the Outer Radiation Belt

    Science.gov (United States)

    Green, J. C.; Onsager, T. G.; O'Brien, P.

    2003-12-01

    Since the discovery of earth's radiation belts researchers have sought to identify the mechanisms that dictate the seemingly erratic relativistic electron flux levels in the outer belt. Contrary to intuition, relativistic electron flux levels do not always increase during geomagnetic storms even though these storms signify enhanced energy input from the solar wind to the magnetosphere [Reeves et al., 2003; O'Brien et al., 2001]. The fickle response of the radiation belt electrons to geomagnetic activity suggests that flux levels are determined by the outcome of a continuous competition between acceleration and loss. Some progress has been made developing and testing acceleration mechanisms but little is known about how relativistic electrons are lost. We examine relativistic electron losses in the outer belt focusing our attention on flux decrease events of the type first described by Onsager et al. [2002]. The study showed a sudden decrease of geosynchronous >2MeV electron flux occurring simultaneously with local stretching of the magnetic field. The decrease was first observed near 15:00 MLT and progressed to all local times after a period of ˜10 hours. Expanding on the work of Onsager et al. [2002], we have identified ˜ 51 such flux decrease events in the GOES and LANL data and present the results of a superposed epoch analysis of solar wind data, geomagnetic activity indicators, and locally measured magnetic field and plasma data. The analysis shows that flux decreases occur after 1-2 days of quiet condition. They begin when either the solar wind dynamic pressure increases or Bz turns southward pushing hot dense plasma earthward to form a partial ring current and stretched magnetic field at dusk. Adiabatic electron motion in response to the stretched magnetic field may explain the initial flux reduction; however, often the flux does not recover with the magnetic field recovery, indicating that true loss from the magnetosphere is occurring. Using Polar and

  13. Bio-assessment of water pollution in coal belt

    International Nuclear Information System (INIS)

    Mishra, P.K.

    1998-01-01

    Water pollution in coal belt has attracted attention of scientists as well as general people. Implication of water pollution on bio-system is still a more important issue and a lot of information has been accumulated. Apart from conventional methods of pollution monitoring, bio-monitoring is comparatively a new approach and a proper methodology is still in pipeline. The present study reviews various methods of bio-monitoring and compare various methodologies suggested at population level with conventional methods. The results indicated that the bio-assessment methodology can be a tool and hence be developed. (author)

  14. Canadian radiation belt science in the ILWS era

    Science.gov (United States)

    Mann, I. R.

    The Outer Radiation Belt Injection, Transport, Acceleration, and Loss Satellite (ORBITALS) is a Canadian Space Agency small satellite mission proposed as a Canadian contribution to the satellite infrastructure for the International Living With a Star (ILWS) program. Planned to operate contemporaneously with the NASA Radiation Belt Storm Probes (RBSP), the ORBITALS will monitor the energetic electron and ion populations in the inner magnetosphere across a wide range of energies (keV to tens of MeV) as well as the dynamic electric and magnetic fields, waves, and cold plasma environment which govern the injection, transport, acceleration and loss of these energetic and space weather critical particle populations in the inner magnetosphere. Currently in Phase A Design Study, the ORBITALS will be launched into a low-inclination GTO-like orbit which every second orbit maximizes the long lasting apogee-pass conjunctions with both the ground-based instruments of the Canadian Geospace Monitoring (CGSM) array as well as with the GOES East and West and geosynchronous communications satellites in the North American sector. In a twelve-hour orbit, every second apogee will conjunct with instrumentation 180 degree in longitude away in the Asian sector. Specifically, the ORBITALS will make the measurements necessary to reach reveal fundamental new understanding of the relative importance of different physical processes (for example VLF verses ULF waves) which shape the energetic particle populations in the inner magnetosphere, as well as providing the raw radiation measurements at MEO altitudes necessary for the development of the next-generation of radiation belt specification models. On-board experiments will also monitor the dose, single event upset, and deep-dielectric charging responses of electronic components on-orbit. Supporting ground-based measurements of ULF and higher frequency wave fields from the Canadian CARISMA (www.carisma.ca) magnetometer array, as well as from

  15. Coal-oil gold agglomeration assisted flotation to recover gold from refractory ore

    Science.gov (United States)

    Otsuki, A.; Yue, C.

    2017-07-01

    This study aimed to investigate the applicability of coal-oil gold agglomeration (CGA) assisted flotation to recover gold from a refractory ore. The ore with the grade of 2-5 g/t was tested with the CGA-flotation process in six different size fractions from 38 to 300 urn using different collector types and dosages. In addition, the flotation without CGA was performed under the same condition for comparison. The results showed that the higher gold grade and recovery were achieved by applying the CGA-flotation, compared with the flotation without CGA. More than 20-60 times grade increase from the head grade was obtained with CGA-flotation. The elemental analysis of gold and sulphur explained their relationship with gold recovery. The results well indicated the applicability of CGA to upgrade the refractory gold ore.

  16. Effects of dissolucytotic gold ions on recovering brain lesions.

    Science.gov (United States)

    Danscher, Gorm; Larsen, Agnete

    2010-04-01

    Recent experimental research has shown that metallic gold releases charged gold atoms when placed intracerebrally and that the liberated gold ions affect inflammation in the brain. The observations suggest that metallic gold can be used as a safe suppressor of inflammation in the central nervous system.

  17. Electroplating of gold using a sulfite-based electrolyte

    NARCIS (Netherlands)

    Smalbrugge, E.; Jacobs, B.; Falcone, S.; Geluk, E.J.; Karouta, F.; Leijtens, X.J.M.; Besten, den J.H.

    2000-01-01

    Electroplating of gold is often used in optoelectronic and microelectronic devices for air-bridges, heat-sinks or gold-bumps for flip-chip techniques. The gold-cyanide electrolytes, which are commonly used in gold-electroplating, are toxic and attack resist patterns causing cracks during the plating

  18. A study on gold detection in Wenyu gold mine with XRF techniques

    International Nuclear Information System (INIS)

    Liu Liuchun

    1988-01-01

    A portable X ray fluorescence analyzer was used for detecting fluorcescent X rays from the elements associated with gold ores. Fe, As and Ni were chosen to be the indicator elements to analyse rock samples in Wenyu gold mine. Optimum indicators were determined, and it had proved to be successful to detect gold indirectly by measuring the yields of characteristic X rays of the elements. The method provided also valuable information on geology mapping and deposits forming environment

  19. Electrocatalytic glucose oxidation at gold and gold-carbon nanoparticulate film prepared from oppositely charged nanoparticles

    International Nuclear Information System (INIS)

    Karczmarczyk, Aleksandra; Celebanska, Anna; Nogala, Wojciech; Sashuk, Volodymyr; Chernyaeva, Olga; Opallo, Marcin

    2014-01-01

    Graphical abstract: - Highlights: • Gold nanoparticulate film electrodes were prepared by layer-by-layer method from oppositely charged nanoparticles. • Positively charged nanoparticles play dominant role in glucose oxidation in alkaline solution. • Gold and gold-carbon nanoparticulate film electrodes exhibit similar glucose oxidation current and onset potential. - Abstract: Electrocatalytic oxidation of glucose was studied at nanoparticulate gold and gold-carbon film electrodes. These electrodes were prepared by a layer-by-layer method without application of any linker molecules. Gold nanoparticles were stabilized by undecane thiols functionalized by trimethyl ammonium or carboxylate groups, whereas the carbon nanoparticles were covered by phenylsulfonate functionalities. The gold nanoparticulate electrodes were characterized by UV-vis and XPS spectroscopy, atomic force microscopy and voltammetry, before and after heat-treatment. Heat-treatment facilitates the aggregation of the nanoparticles and affects the structure of the film. The comparison of the results obtained with film electrodes prepared from gold nanoparticles with the same charge and with gold-carbon nanoparticulate electrodes, proved that positively charged nanoparticles are responsible for the high electrocatalytic activity, whereas negatively charged ones act rather as a linker of the film

  20. Formation of gold nanorods and gold nanorod films for surface-enhanced Raman scattering spectroscopy

    International Nuclear Information System (INIS)

    Trotsyuk, L.L.; Kulakovich, O.S.; Shabunya-Klyachkovskaya, E.V.; Gaponenko, S.V.; Vashchenko, S.V.

    2016-01-01

    The formation of gold nanorods as well as thin films prepared via electrostatic deposition of gold nanorods has been investigated. The obtained gold nanorods films have been used as substrates for the surface-enhanced Raman scattering analysis of sulfur-free organic molecules mitoxantrone and malachite green as well as inorganic malachite microcrystals for the first time. The additional modification of films with L-cysteine allows one to significantly extend the use of gold nanorods for the surface-enhanced Raman scattering analysis. (authors)