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Sample records for au-cu skarn deposits

  1. Characteristics of melt inclusions in skarn minerals from Fe,Cu(Au) and Au(Cu) ore deposits in the region from Daye to Jiujiang

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Bin; (赵斌); ZHAO; Jinsong; (赵劲松); LI; Zhaolin; (李兆麟); ZHANG; Zhongze; (张重泽); PENG; Zhuolun; (彭卓伦)

    2003-01-01

    A vast amount of the melt inclusions and fluid-melt inclusions have been found in skarn minerals from Fe, Cu(Au) and Au(Cu) ore deposits distributed from Daye to Jiujiang along the Yangtze River besides vapor-liquid inclusions. The melt inclusions are many and varied in shape. They mainly consist of crystallized silicate phases (CSi), iron phases (Fe), amorphous silicate phases (ASi) and vapor (V) with different volume percentages, and some of them contain several crystallized silicate phases. These melt inclusion sizes are commonly (10-46)×(6-15) μm2. A difference between the fluid-melt inclusions and melt inclusions is that the liquid phase appears in the former and their homogenization temperatures are lower than the latter. We measured the homogenization temperatures of the melt inclusions, fluid-melt inclusions and fluid inclusions in ten thin sections from eight ore deposits on Leitz microscope heating stage 1350 which was made in Germany. Forty-eight homogenization temperature values have been obtained. Among them, thirty-nine values are homogenization temperatures of the melt inclusions in garnet and pyroxene from skarns, two values are homogenization temperatures of fluid-melt inclusions, others belong to the fluid inclusions. Melt inclusions in garnet and pyroxene have homogenization temperatures of 890-1115℃. Fluid-melt inclusions have homogenization temperatures of 745-750℃. Homogenization temperatures of fluid inclusions are between 580℃ and 675℃. The average of thirty- nine homogenization temperatures for the melt inclusions is 1029.9℃. Wethink studied skarns to be magmatic genesis on the basis of available data relative to the characteristic features of phase states within the melt inclusions and the fluid melt inclusions and their homogenization temperatures.

  2. Transitional adakite-like to calc-alkaline magmas in a continental extensional setting at La Paz Au-Cu skarn deposits, Mesa Central, Mexico: metallogenic implications

    OpenAIRE

    Porfirio J. Pinto Linares; Gilles Levresse; Jordi Tritlla; Víctor A. Valencia; José M. Torres Aguilera; Manuel González; David Estrada

    2008-01-01

    The granodiorite intrusions with associated Cu-Au skarn mineralization of La Paz district are located in the east part of the Mesa Central of Mexico. The skarn developed at the contact between a middle Cretaceous calc-argillaceous sedimentary sequence and the magmatic intrusions. A Ag-Pb-Zn vein system postdates the intrusive-skarn assemblage. Two well defined fault systems (N-S and E-W) divide the La Paz district. The N-S Dolores fault, with a normal vertical displacement estimated between 5...

  3. Mineralogy of the Panulcillo skarn copper deposit, Coquimbo Region, Chile

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    Asahiko Sugaki

    2000-12-01

    Full Text Available The Panulcillo skarn copper deposit developed in an Early Cretaceous (Valanginian volcano-sedimentary sequence intruded by a Cretaceous diorite. The exoskarn zone of the deposit is composed of garnet skarn comprising grandite garnet (Ad12.9-47.4 and phlogopite with lesser amounts of diopside (Di89.6-91.6, clintonite, pargasitic hornblende, actinolite, pumpellyite, chlorite, quartz and calcite, exhibiting characteristic Mg-Al-rich assemblages. The principal ores consist of chalcopyrite, monoclinic pyrrhotite, sphalerite, pyrite, and magnetite with small amounts of galena, and locally secondary marcasite, hematite and covellite, generally filling interstices of the garnet skarn. Chalcopyrite shows characteristic polysynthetic twinning, normally including fine star-like crystals of sphalerite as exsolution products. Sphalerite contains 14.4 - 22.5 mol% FeS and 1.6 - 9.2 mol% MnS, and is associated intimately with chalcopyrite. It is highly likely that such Fe-rich sphalerite has coexisted primarily with hexagonal pyrrhotite under low-sulfidation conditions at higher temperatures than 275 - 254°C, below which monoclinic pyrrhotite is stableMineralogía del yacimiento cuprífero tipo skarn de Panulcillo, Región de Coquimbo, Chile. El yacimiento tipo skarn de cobre de Panulcillo se desarrolló en una secuencia volcano-sedimentaria de edad cretácica inferior (Valanginiana, la que es intruida por un cuerpo cretácico de composición diorítica. La zona del exoskarn característicamente presenta una asociación mineralógica rica en Mg y Al, y corresponde a un skarn de granate compuesto por granate tipo ugrandita (Ad12.9-47.4 y flogopita con candidades menores de diópsido (Di89.6-91.6, clintonita, hornblenda pargasítica, actinolita, pumpellita, clorita, cuarzo y calcita. Los minerales metálicos consisten mayoritariamente en calcopirita, pirrotina monoclínica, esfalerita, pirita, y magnetita con menos galena, localmente marcasita, hematita y

  4. Genesis of Yangla Banded Skarn-Hosted Copper Deposit in Tethys Orogenic Belt of Southwestern China

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Yangla copper deposit is the largest banded skarn-hosted copper deposit found recently in the Tethys orogenic belt of Southwestern China. On the basis of the study of distribution, petrology and mineralogy as well as major element, REE and isotope geochemistry, the authors find that the banded skarn, which hosts the deposit, was precipitated from hydrothermal solutions in the form of exhalate sediment. Therefore, the banded skarn-hosted copper deposit is a Sedex-type deposit, with a series of stacked, conformable lenses underlain by at least one stringer zone. The deposit, intercalated at the contact of lower clastic rock and upper carbonate rock of Gajinxueshan Group, was formed in the Carboniferous ((296.1±7.0) Ma), contemporary to the host Gajinxueshan Group. The interpretation of the genesis of Yangla banded skarn-hosted copper deposit is of fundamental exploration significance for the discovery of Sedex-type copper deposit in the region.

  5. Genetic relationships between skarn ore deposits and magmatic activity in the Ahar region, Western Alborz, NW Iran

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    Mollai Habib

    2014-06-01

    Full Text Available Paleocene to Oligocene tectonic processes in northwest Iran resulted in extensive I-type calc-alkaline and alkaline magmatic activity in the Ahar region. Numerous skarn deposits formed in the contact between Upper Cretaceous impure carbonate rocks and Oligocene-Miocene plutonic rocks. This study presents new field observations of skarns in the western Alborz range and is based on geochemistry of igneous rocks, mineralogy of the important skarn deposits, and electron microprobe analyses of skarn minerals. These data are used to interpret the metasomatism during sequential skarn formation and the geotectonic setting of the skarn ore deposit related igneous rocks. The skarns were classified into exoskarn, endoskarn and ore skarn. Andraditic garnet is the main skarn mineral; the pyroxene belongs to the diopside-hedenbergite series. The skarnification started with pluton emplacement and metamorphism of carbonate rocks followed by prograde metasomatism and the formation of anhydrous minerals like garnet and pyroxene. The next stage resulted in retro gradation of anhydrous minerals along with the formation of oxide minerals (magnetite and hematite followed by the formation of hydrosilicate minerals like epidote, actinolite, chlorite, quartz, sericite and sulfide mineralization. In addition to Fe, Si and Mg, substantial amounts of Cu, along with volatile components such as H2S and CO2 were added to the skarn system. Skarn mineralogy and geochemistry of the igneous rocks indicate an island arc or subduction-related origin of the Fe-Cu skarn deposit.

  6. Chronology and origin of Au-Cu deposits related to Paleozoic intracontinental rifting in West Tianshan Mountains, NW China

    Institute of Scientific and Technical Information of China (English)

    LI; Huaqin(李华芹); CHEN; Fuwen(陈富文)

    2002-01-01

    Located between the Tarim platform and Junggar massif, the West Tianshan intracontinental rift abuts against the China-Kazakhstan boundary in the west part, borders on the Yilianhabierga late Paleozoic relic ocean basin and the South Tianshan late Paleozoic ocean basin respectively in the northeast separated by the Aibi Lake fault and in the southeast by the fault along the southern margin of the Yili massif. During the development and after the close of the West Tianshan intracontinental rifting in the Carboniferous-Permian period, a series of nonferrous and precious metal mineralizations occurred with the Au-Cu deposits being the most important. Isotopic chronologic study of representative deposits of different types shows that gold-copper mineralization in the West Tianshan intracontinental rift zone mainly happened during the middle-late Hercynian Period, among which the Axi volcanic hydrothermal type gold deposit was formed during the Carboniferous with a fluid inclusion Rb-Sr isochron age of (339 ± 28) Ma; the Qiabukanzhuota quartzolite type gold deposit has a Rb-Sr isochron age of (312 ± 46) Ma; the Tawuerbieke porphyry type gold deposit has a Rb-Sr isochron age of (295 ± 16) Ma; the Jingbulak magmatic liquation Cu-Ni deposit and the Musizaote porphyry type Cu deposit have the forming ages of 300 Ma ± and 250 Ma ±, respectively. Analyses of crustal evolution and metallogenetic geological backgrounds of Au-Cu mineralizations in the studied area shows a close correlation with the rifting.

  7. Garnetization as a ground preparation process for copper mineralization: evidence from the Mazraeh skarn deposit, Iran

    Science.gov (United States)

    Karimzadeh Somarin, Alireza

    2010-03-01

    The Mazraeh Cu-Fe skarn deposit, NW Iran is the result of the intrusion of an Oligocene-Miocene granitic pluton into Cretaceous calcareous rocks. The pluton ranges in composition from monzonite to quartz monzonite, monzogranite, tonalite and granodiorite with I-type, calc-alkaline, and weakly peraluminous characteristics. The Mazraeh pluton was emplaced in a volcanic arc setting in an active continental margin at a depth of ~8 km. Pyroxene skarn, garnet skarn, and epidote skarn zones were formed during the intrusive phase. The garnet skarn developed as exoskarn and endoskarn from the calcareous wall rocks and the pluton, respectively, prior to mineralization. Garnet skarn from the exoskarn zone is identified by relict layering inherited from the precursor calcareous lithologies. Mass balance calculation of garnet skarn in the endoskarn zone indicates that hydrothermal fluids originating from the cooling magma introduced Si, Fe, Mn, Ca, Mg, P, Ag, Cu, Zn, La, Pb, Cd, Mo, and Y. The main mass loss in the garnet skarn was due to destruction of feldspars in the Mazraeh plutonic rocks and leaching of K2O and Na2O. Released Ca has been fixed in the andraditic garnet. Garnetization of the Mazraeh pluton was accompanied by mass and volume increase. The magnitude of these changes depends mainly on the degree of alteration and composition of the precursor. The brittle behavior of the endoskarn zone was increased due to formation of massive garnet which subsequently fractured. These fractures not only facilitated movement of hydrothermal fluids but also provided new locations for Cu mineralization. Therefore locating strongly garnetized zones may be a vector to ore in skarn deposits.

  8. Timing and setting of skarn and iron oxide formation at the Smältarmossen calcic iron skarn deposit, Bergslagen, Sweden

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    Jansson, Nils F.; Allen, Rodney L.

    2013-03-01

    Abundant iron oxide deposits including banded iron formations, apatite iron oxide ores, and enigmatic marble/skarn-hosted magnetite deposits occur in the Palaeoproterozoic Bergslagen region, southern Sweden. During the last 100 years, the latter deposit class has been interpreted as contact metasomatic skarn deposits, metamorphosed iron formations, or metamorphosed carbonate replacement deposits. Their origin is still incompletely understood. At the Smältarmossen mine, magnetite was mined from a ca. 50-m-thick calcic skarn zone at the contact between rhyolite and stratigraphically overlying limestone. A syn-volcanic dacite porphyry which intruded the footwall has numerous apophyses that extend into the mineralized zone. Whole-rock lithogeochemical and mineral chemical analyses combined with textural analysis suggests that the skarns formed by veining and replacement of the dacite porphyry and rhyolite. These rocks were added substantial Ca and Fe, minor Mg, Mn, and LREE, as well as trace Co, Sn, U, As, and Sr. In contrast, massive magnetite formed by pervasive replacement of limestone. Tectonic fabrics in magnetite and skarn are consistent with ore formation before or early during Svecokarelian ductile deformation. Whereas a syngenetic-exhalative model has previously been suggested, our results are more compatible with magnetite formation at ca. 1.89 Ga in a contact metasomatic skarn setting associated with the dacite porphyry.

  9. Geochemistry of magnetite from porphyry Cu and skarn deposits in the southwestern United States

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    Nadoll, Patrick; Mauk, Jeffrey L.; LeVeille, Richard A.; Koenig, Alan E.

    2015-01-01

    A combination of petrographic observations, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and statistical data exploration was used in this study to determine compositional variations in hydrothermal and igneous magnetite from five porphyry Cu–Mo and skarn deposits in the southwestern United States, and igneous magnetite from the unmineralized, granodioritic Inner Zone Batholith, Japan. The most important overall discriminators for the minor and trace element chemistry of magnetite from the investigated porphyry and skarn deposits are Mg, Al, Ti, V, Mn, Co, Zn, and Ga—of these the elements with the highest variance for (I) igneous magnetite are Mg, Al, Ti, V, Mn, Zn, for (II) hydrothermal porphyry magnetite are Mg, Ti, V, Mn, Co, Zn, and for (III) hydrothermal skarn magnetite are Mg, Ti, Mn, Zn, and Ga. Nickel could only be detected at levels above the limit of reporting (LOR) in two igneous magnetites. Equally, Cr could only be detected in one igneous occurrence. Copper, As, Mo, Ag, Au, and Pb have been reported in magnetite by other authors but could not be detected at levels greater than their respective LORs in our samples. Comparison with the chemical signature of igneous magnetite from the barren Inner Zone Batholith, Japan, suggests that V, Mn, Co, and Ga concentrations are relatively depleted in magnetite from the porphyry and skarn deposits. Higher formation conditions in combination with distinct differences between melt and hydrothermal fluid compositions are reflected in Al, Ti, V, and Ga concentrations that are, on average, higher in igneous magnetite than in hydrothermal magnetite (including porphyry and skarn magnetite). Low Ti and V concentrations in combination with high Mn concentrations are characteristic features of magnetite from skarn deposits. High Mg concentrations (magnetite from magnesian skarn and likely reflect extensive fluid/rock interaction. In porphyry deposits, hydrothermal magnetite from different

  10. Genetic relationships between skarn ore deposits and magmatic activity in the Ahar region, Western Alborz, NW Iran

    OpenAIRE

    Mollai Habib; Pe-Piper Georgia; Dabiri Rahim

    2014-01-01

    Paleocene to Oligocene tectonic processes in northwest Iran resulted in extensive I-type calc-alkaline and alkaline magmatic activity in the Ahar region. Numerous skarn deposits formed in the contact between Upper Cretaceous impure carbonate rocks and Oligocene-Miocene plutonic rocks. This study presents new field observations of skarns in the western Alborz range and is based on geochemistry of igneous rocks, mineralogy of the important skarn deposits, and electron microprobe analyses of ska...

  11. High and intermediate sulphidation environment in the same hydrothermal deposit: the example of Au-Cu Palai???Islica deposit, Carboneras (Almer??a)

    OpenAIRE

    Carrillo-Ros??a, Javier; Morales-Ruano, Salvador; Boyce, Adrian J.; Fallick, Anthony E.

    2003-01-01

    Two epithermal environments have been identified in the Miocene Palai???Islica Au???Cu deposit: A) Intermediate sulphidation, hosted mainly in quartz veins, comprises pyrite, chalcopyrite, sphalerite and galena as the major sulphides, which are accompanied by a variety of Ag-bearing accessory minerals. Au???Ag alloys are the only gold-bearing phase. The veins are enclosed by sericitic and chloritic alteration. Fluid inclusions in quartz, sphalerite and calcite give Th between 118???453 ??C, a...

  12. The origin of skarn beds, Ryllshyttan Zn-Pb-Ag + magnetite deposit, Bergslagen, Sweden

    Science.gov (United States)

    Jansson, Nils F.; Allen, Rodney L.

    2011-11-01

    Thin- to medium-bedded, stratiform calc-silicate deposits (banded skarns) are a peculiar, but important, component of the supracrustal successions in the Palaeoproterozoic Bergslagen mining district of central Sweden. They are referred to as "skarn-banded leptites" in the literature and are common in areas and at stratigraphic levels that contain iron oxide and base metal sulphide deposits. The stratigraphic hanging wall of the stratabound Ryllshyttan Zn-Pb-Ag + magnetite deposit at Garpenberg, contains approximately 100-150 m of interbedded aluminous skarn beds and rhyolitic ash-siltstones. The skarn beds are mineralogically variable and dominantly composed of grandite, spessartine, epidote, actinolite, quartz, clinopyroxene, and locally magnetite. Integrated field-mapping, and whole-rock lithogeochemical, microscopic and mineral chemical analyses suggest that the stratiform skarn beds are the products of at least two discrete hydrothermal events and subsequent metamorphism. The first event comprised accumulation in a quiescent subaqueous environment, below wave base, of calcareous and ferruginous sediments rich in Fe, Mn, Ca, and Mg. These chemical sediments were deposited concurrently with rhyolitic ash-silt sedimentation, thus forming a (now metamorphosed) laminated calcareous Fe formation with both a detrital rhyolitic component and rhyolitic siltstone interbeds. Positive Eu-anomalies and negative Ce-anomalies for normalized rare earth element analyses of skarn beds suggest that the iron may have been derived from exhalation of hot and reduced hydrothermal fluids, which upon mixing with more oxidized seawater, precipitated Fe oxides and/or carbonates that settled from suspension to the seafloor. The size of the positive Eu-anomalies of the chemical sediments are modified by the content of rhyolitic volcaniclastic material, which has a negative Eu anomaly, such that positive Eu-anomalies are only observed in skarn beds that possess a minor volcaniclastic

  13. Geology and Characteristics of Pb-Zn-Cu-Ag Skarn Deposit at Ruwai, Lamandau Regency, Central Kalimantan

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    Arifudin Idrus

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v6i4.126This study is dealing with geology and characteristics of mineralogy, geochemistry, and physicochemical conditions of hydrothermal fluid responsible for the formation of skarn Pb-Zn-Cu-Ag deposit at Ruwai, Lamandau Regency, Central Kalimantan. The formation of Ruwai skarn is genetically associated with calcareous rocks consisting of limestone and siltstone (derived from marl? controlled by NNE-SSW-trending strike slip faults. It is localized along N 70° E-trending thrust fault, which also acts as the contact zone between sedimentary and volcanic rocks in the area. The Ruwai skarn is mineralogically characterized by prograde alteration comprising garnet (andradite and clino-pyroxene (wollastonite, and retrograde alteration composed of epidote, chlorite, calcite, and sericite. Ore mineralization is typified by sphalerite, galena, and chalcopyrite, formed at early retrograde stage. Galena is typically enriched in silver up to 0.45 wt % and bismuth of about 1 wt %. No Ag-sulphides are identified within the ore body. Geochemically, SiO is enriched and CaO is depleted in limestone, consistent with silicic alteration (quartz and calc-silicate and decarbonatization of the wallrock. The measured resources of the deposit are 2,297,185 tonnes at average grades of 14.98 % Zn, 6.44% Pb, 2.49 % Cu, and 370.87 g/t Ag. Ruwai skarn orebody was originated at moderate temperatures of 250 - 266 °C and low salinity of 0.3 - 0.5 wt.% NaCl eq. The late retrograde stage was formed at low temperature of 190 - 220 °C and low salinity of ~0.35 wt.% NaCl eq., which was influenced by meteoric water incursion at the late stage of the Ruwai Pb-Zn-Cu-Ag skarn formation.

  14. Fluid-melt Inclusions in Fluorite of the Huanggangliang Skarn Iron-Tin Deposit and Their Significance to Mineralization

    Institute of Scientific and Technical Information of China (English)

    王莉娟; 王京彬; 王玉往; 毛骞

    2001-01-01

    For the first time, fluid-melt inclusions are found in fluorite of the Huanggangliang skarn iron-tin deposit (HSID). The fluorite was formed in the main stage of mineralization, named the hydro-skarnization stage. The inclusions contain various components such as Fe, Mg and Cr from deep sources. The melts of primary inclusions are mainly Ca- and F-rich and those of secondary inclusions tend to become Si-rich. During this evolution process, the melts and iron daughter minerals decreased and even vanished. These facts reveal that the evolution of the primary mineralizing fluids and the differentiation of the fluids and melts are the main factors leading to the deposition of Fe, Sn and other elements. This discovery confirms the magmatic genesis of the HSID and has filled in the gaps in the research of magmatogenic skarn deposits and furnished new methods for such research. Furthermore, it has enlarged the scope of the research on fluid inclusions.

  15. W-Au skarns in the Neo-Proterozoic Seridó Mobile Belt, Borborema Province in northeastern Brazil: an overview with emphasis on the Bonfim deposit

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    Souza Neto, João Adauto; Legrand, Jean Michel; Volfinger, Marcel; Pascal, Marie-Lola; Sonnet, Philippe

    2008-02-01

    The Seridó Mobile Belt (SMB) is located in the Borborema Province in northeastern Brazil and consists of a gneiss basement (Archean to Paleo-Proterozoic), a metasedimentary sequence (marble, quartzites, and schists), and the Brasiliano igneous suite (both of Neo-Proterozoic age). In this region, skarns occur within marble and at the marble-schist contact in the metasedimentary sequence. Most of the skarn deposits have been discovered in the early 1940s, and since then, they have been exploited for tungsten and locally gold. Recently, the discovery of gold in the Bonfim tungsten skarn has resulted in a better understanding of the skarn mineralization in this region. The main characteristics of the SMB skarns are that they are dominantly oxidized tungsten skarns, with the exception of the Itajubatiba and Bonfim gold-bearing skarns, which are reduced based on pyrrhotite as the dominant sulfide, garnet with high almandine and spessartine component, and elevated gold contents. In the Bonfim deposit, pressure estimates indicate that the skarns formed at 10- to 15-km depth. The mineralized skarns present the prograde stage with almandine, diopside, anorthite, and actinolite-magnesio-hornblende, and titanite, apatite, allanite, zircon, and monazite as accessory minerals. The retrograde stage is characterized by alkali feldspar, clinozoisite-zoisite-sericite, calcite, and quartz. Scheelite occurs in four ore-shoots distributed within the marble and at the marble-schist contact. The main ore body is 5-120 cm wide and contains an average of 4.8-wt.% WO3, which occurs in the basal marble-schist contact. Fold hinges appear to control the location of high-grade scheelite. The late-stage gold mineralization contains bismite (Bi2O3), fluorine-bearing bismite, native bismuth, bismuthinite (Bi2S3), and joseite [Bi4(Te,S)3], and also chlorite, epidote, prehnite, chalcopyrite, and sphalerite. This gold-bismuth-tellurium mineralization exhibits a typical late character and occurs as a

  16. The origin and evolution of skarn-forming fluids from the Phu Lon deposit, northern Loei Fold Belt, Thailand: Evidence from fluid inclusion and sulfur isotope studies

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    Kamvong, Teera; Zaw, Khin

    2009-05-01

    The Phu Lon skarn Cu-Au deposit is located in the northern Loei Fold Belt (LFB), Thailand. It is hosted by Devonian volcano-sedimentary sequences intercalated with limestone and marble units, intruded by diorite and quartz monzonite porphyries. Phu Lon is a calcic skarn with both endoskarn and exoskarn facies. In both skarn facies, andradite and diopside comprise the main prograde skarn minerals, whereas epidote, chlorite, tremolite, actinolite and calcite are the principal retrograde skarn minerals. Four types of fluid inclusions in garnet were distinguished: (1) liquid-rich inclusions; (2) daughter mineral-bearing inclusions; (3) salt-saturated inclusions; and (4) vapor-rich inclusions. Epidote contains only one type of fluid inclusion: liquid-rich inclusions. Fluid inclusions associated with garnet (prograde skarn stage) display high homogenization temperatures and moderate salinities (421.6-468.5 °C; 17.4-23.1 wt% NaCl equiv.). By contrast, fluid inclusions associated with epidote (retrograde skarn stage) record lower homogenization temperatures and salinities (350.9-399.8 °C; 0.5-8 wt% NaCl equiv.). These data suggest a possible mixing of saline magmatic fluids with external, dilute fluid sources (e.g., meteoric fluids), as the system cooled. Some fluid inclusions in garnet contain hematite daughters, suggesting an oxidizing magmatic environment. Sulfur isotope determinations on sulfide minerals from both the prograde and retrograde stages show a uniform and narrow range of δ34S values (-2.6 to -1.1 ‰ δ34S), suggesting that the ore-forming fluid contained sulfur of orthomagmatic origin. Overall, the Phu Lon deposit is interpreted as an oxidized Cu-Au skarn based on the mineralogy and fluid inclusion characteristics.

  17. Geological, geochronological, and mineralogical constraints on the genesis of the Chengchao skarn Fe deposit, Edong ore district, Middle-Lower Yangtze River Valley metallogenic belt, eastern China

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    Yao, Lei; Xie, Guiqing; Mao, Jingwen; Lü, Zhicheng; Zhao, Caisheng; Zheng, Xianwei; Ding, Ning

    2015-04-01

    The Edong ore district is located within the westernmost Middle-Lower Yangtze River Valley metallogenic belt (MLYRB), and hosts the largest concentration of skarn Fe deposits in China, although the origin of these deposits remains controversial. The Chengchao deposit is the largest skarn Fe deposit so far discovered within the MLYRB, and provides a good opportunity to address the debate surrounding the origin of these skarn Fe deposits. Here, we present geological, geochronological, and mineralogical data from the Chengchao skarn deposit and associated intrusions, and discuss the relationships between granitoids and mineralization in the Chengchao deposit. The NW-SE-striking orebodies in the study area have porphyritic quartz monzonite and/or granite footwalls, and Triassic marble or diorite hangingwalls, indicating a spatial relationship between these intrusions and Fe mineralization. Zircon U-Pb data from the granite, porphyritic quartz monzonite, diorite, and porphyritic diabase dike within the deposit show ages of 129 ± 1, 128 ± 1, 140 ± 1, and 126 ± 1 Ma, respectively. These ages and the previously reported ages on the timing of mineralization suggest that the porphyritic quartz monzonite and granite are coeval with the formation of the skarn Fe deposit. Our data confirm that the granitic rocks are temporally associated with Fe mineralization. The prograde substage of skarn development is characterized by two stages of andradite (Adr98-38Grs61-2Prp2-0Sps1-0Alm1-0) and diopside (Di95-61Hd37-5Jo3-0), including an early stage of garnet and pyroxene formation that is genetically associated with the mineralization. The early stage garnets are more andradite-rich (Adr98-50Grs49-2Prp1-0Sps1-0Alm0) than the late veinlet garnets characterized by intermediate grandite compositions (Adr67-37Grs61-31Prp2-0Sps1-0Alm1-0). The early stage pyroxenes (Di95-74Hd26-5Jo1-0) are compositionally distinct from the late stage pyroxenes (Di84-61Hd37-16Jo3-0). Compositional

  18. [Study on Mineralogical Characteristics of Quartz and Calcite from Feieling Skarn-Type Pb-Zn Deposit in Southwest Margin of Yunkai Massif].

    Science.gov (United States)

    Zeng, Chang-yu; Zhao, Ming-zhen; Li, Hong-zhong; Niu, Jia; Zhang, Jie-tang; He, Jun-guo; Zhou, Yong-zhang; Yang, Zhi-jun

    2015-09-01

    The Feieling Pb-Zn deposit of skarn-type is located the in Southwest margin of Yunkai massif, China. This ore deposit can be divided into wall rock near ore, concealed rock mass, endoskarn, exoskarn and orebody. The Raman and FTIR spectrum are conducted to study the mineralogical characteristics of quartz and calcite from five types of rocks from Feieling skarn-type deposit. The analysis shows that the quartz included in the near ore wall rock, endoskarn and exoskarn, comparing with recrystallized quartz of concealed rock mass, has a tend to change into low symmetry quartz in varying degrees. The crystalinity and order degree of quartz from near ore wall rock to concealed rock mass and to endoskarn are becoming higher, but that of quartz from different exoskarn samples display no regular. The origin or the quartz microstructure changes may be related to the multi-stage evolution of skarn mineralization process. The quartz, included in near ore wall rock, endoskarn and exoskarn, become easier to recrystallize and adjust microstructure under the influence of the multi-stage hydrothermal and temperature effect. In anyone sample, the earlier crystalline calcite, showing subhedral-euhedral crystal, display higher crystalinity and order degree. On the contrary, the later crystalline calcite, showing xenomorphic crystal, display lower crystalinity and order degree. Calcite crystal of exoskarn rock contains some silica impurity, while endoskarn and orebody rock is pure. The purity of calcite crystal may relate to Multi-stage evolution of skarn mineralization process. At the early and late skarn stage, active silica-containing fluid is easier to join into calcite, which is under higher temperature environments. On the contrary, at the late quartz-surfide stage, the later crystalized calcite displays higher purity, which is under lower temperature environments. Therefore, spectral characteristics of quartz and calcite reflect multi-stage evolution of skarn mineralization

  19. Geochemical Behaviors of REE and Other Trace Elements during the Formation of Strata-bound Skarns and Related Deposits:A Case Study of the Dongguashan Cu(Au) Deposit,Anhui Province,China

    Institute of Scientific and Technical Information of China (English)

    LING Qicong; LIU Congqiang

    2003-01-01

    REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demonstrated that the high-field-strength (HFS) elements Zr, Hf, Th and Nb were immobile while other trace elements were mobile during the formation of skarns and related deposits. REE and ore-forming elements such as Cu and Ag in hydrothermally-altered marbles and skarns were provided primarily by hydrothermal fluids. In the direction transverse of the strata, the more deeply the marbles were altered, the higher the total REE abundance and the larger the negative Eu anomalies would be. The chondrite-normalized REE patterns of skarns are similar to those of the marbles, but the former are distinguished by much higher REE contents and more remarkable negative Eu anomalies. Those patterns were apparently not inherited from the marble protolith, but were controlled by garnets, which were determined by the hydrothermal solutions involved in the infiltration metasomatism. The hydrothermal fluids are characterized by having slightly right-hand dipping REE patterns, being enriched in LREE and having strongly negative Eu anomalies. The uptake of REE from hydrothermal fluids during the growth of garnet crystals resulted in the garnets having similar REE patterns to the hydrothermal fluids. Based on the spatial variation of REE in skarns and the structures of the hosting strata, we can get a better understanding of the transport path and pattern of the fluids involved in the formation of skarns and their related deposits. REE geochemistry investigation can help elucidate the genesis of skarns and skarn-related deposits.

  20. Enrichment of copper in ore-forming fluid of copper-tungsten mineralization of the Yamaguchi skarn deposit, Iwate, Japan

    International Nuclear Information System (INIS)

    Chemical composition of the fluids in the fluid inclusions of quartz from the pegmatite veins of the Yamaguchi W-Cu skarn deposit was measured by a combination of the crush-leach method in deionized water and chemical analysis using PIXE. Chemical composition of the fluids is characterized by a low molar ratio of Na/K and a high Cu concentration. The molar ratio of Cu/(Cu+Fe+Zn) of the fluid inclusions is higher than that of massive sulfide deposits on the seafloor. The molar ratio of Cu/(Cu+Fe+Zn) of the fluid inclusions is similar to the ratios of the vapor-rich fluid inclusions from the quartz-cassiterite veins hosted within the Mole Granite in New South Wales, Australia. The high Cu concentration in fluid inclusions of quartz associated with the pegmatite veins from the Yamaguchi deposit suggests that the fluid emanating from the Miyako granitic melt at the later stage of crystallization had a high Cu content. (author)

  1. Geochemical and fluid zonation in the skarn environment at the tomboy-minnie gold deposits, Lander County, Nevada

    Science.gov (United States)

    Theodore, T.G.; Howe, S.S.; Blake, D.W.; Wotruba, P.R.

    1986-01-01

    The Tomboy-Minnie gold deposits are related to the middle Tertiary porphyry copper system centered at Copper Canyon. Gold-silver ores in the deposits occur mostly in a pyrrhotite- and pyrite-rich basal 30-m-thick sequence of altered calcareous conglomerate belonging to the Middle Pennsylvanian Battle Formation. The entire mineralized system contained at least 3.3 million troy oz gold before large-scale mining operations began. Alteration in the Tomboy-Minnie deposits includes actinolite- and chlorite-dominant assemblages, in marked contrast to the skarn, potassic, and phyllic assemblages characterizing the copper-gold-silver deposits of the system. Introduction of gold occurred penecontemporaneously with replacement of early diopside-alteration assemblages by actinolite and chlorite. Metals are zoned strongly in the Copper Canyon system: the West and East ore bodies occur in a copper-gold-silver zone that is followed outward by a gold-silver zone which includes the Tomboy deposit and in turn, is succeeded by a lead-zinc-silver zone. Locations of drill holes that have Au/Ag assay ratios of ??? 1 clearly outline the Tomboy-Minnie deposits within an area of rocks with Au/Ag ratios of ??? 0.5. Fluid-inclusion studies suggest wide variations in temperature and chemistry prevailed in the fluids associated with mineralization at the Tomboy. Early fluids associated with diopsidequartz assemblages probably were dominantly CaCl2-rich brines and were boiling at temperatures higher than 500??C. These fluids were progressively enriched in sodium and potassium over time, and during the hydrosilicate stages, temperatures probably ranged from 320 to 500??C at the time actinolite formed, and from 220 to 320??C at the time chlorite was dominant. Sulfur isotopic data suggest that sulfur, mostly from a magmatic or deep-seated crustal source, was transported by hydrothermal fluids as aqueous H2S with a ?? 34S of about 4 ?? 1??? to the West, East, and Tomboy deposits. ?? 1986.

  2. Geochemistry of rare earth elements in the Baba Ali magnetite skarn deposit, western Iran – a key to determine conditions of mineralisation

    Directory of Open Access Journals (Sweden)

    Zamanian Hassan

    2016-03-01

    Full Text Available The Baba Ali skarn deposit, situated 39 km to the northwest of Hamadan (Iran, is the result of a syenitic pluton that intruded and metamorphosed the diorite host rock. Rare earth element (REE values in the quartz syenite and diorite range between 35.4 and 560 ppm. Although the distribution pattern of REEs is more and less flat and smooth, light REEs (LREEs in general show higher concentrations than heavy REEs (HREEs in different lithounits. The skarn zone reveals the highest REE-enriched pattern, while the ore zone shows the maximum depletion pattern. A comparison of the concentration variations of LREEs (La–Nd, middle REEs (MREEs; Sm–Ho and HREEs (Er–Lu of the ore zone samples to the other zones elucidates two important points for the distribution of REEs: 1 the distribution patterns of LREEs and MREEs show a distinct depletion in the ore zone while representing a great enrichment in the skarn facies neighbouring the ore body border and decreasing towards the altered diorite host rock; 2 HREEs show the same pattern, but in the exoskarn do not reveal any distinct increase as observed for LREEs and MREEs. The ratio of La/Y in the Baba Ali skarn ranges from 0.37 to 2.89. The ore zone has the highest La/Y ratio. In this regard the skarn zones exhibit two distinctive portions: 1 one that has La/Y >1 beingadjacent to the ore body and; 2 another one with La/Y < 1 neighbouring altered diorite. Accordingly, the Baba Ali profile, from the quartz syenite to the middle part of the exoskarn, demonstrates chiefly alkaline conditions of formation, with a gradual change to acidic towards the altered diorite host rocks. Utilising three parameters, Ce/Ce*, Eu/Eu* and (Pr/Ybn, in different minerals implies that the hydrothermal fluids responsible for epidote and garnet were mostly of magmatic origin and for magnetite, actinolite and phlogopite these were of magmatic origin with low REE concentration or meteoric water involved.

  3. Geochemistry of rare earth elements in the Baba Ali magnetite skarn deposit, western Iran - a key to determine conditions of mineralisation

    Science.gov (United States)

    Zamanian, Hassan; Radmard, Kaikosrov

    2016-03-01

    The Baba Ali skarn deposit, situated 39 km to the northwest of Hamadan (Iran), is the result of a syenitic pluton that intruded and metamorphosed the diorite host rock. Rare earth element (REE) values in the quartz syenite and diorite range between 35.4 and 560 ppm. Although the distribution pattern of REEs is more and less flat and smooth, light REEs (LREEs) in general show higher concentrations than heavy REEs (HREEs) in different lithounits. The skarn zone reveals the highest REE-enriched pattern, while the ore zone shows the maximum depletion pattern. A comparison of the concentration variations of LREEs (La-Nd), middle REEs (MREEs; Sm-Ho) and HREEs (Er-Lu) of the ore zone samples to the other zones elucidates two important points for the distribution of REEs: 1) the distribution patterns of LREEs and MREEs show a distinct depletion in the ore zone while representing a great enrichment in the skarn facies neighbouring the ore body border and decreasing towards the altered diorite host rock; 2) HREEs show the same pattern, but in the exoskarn do not reveal any distinct increase as observed for LREEs and MREEs. The ratio of La/Y in the Baba Ali skarn ranges from 0.37 to 2.89. The ore zone has the highest La/Y ratio. In this regard the skarn zones exhibit two distinctive portions: 1) one that has La/Y >1 beingadjacent to the ore body and; 2) another one with La/Y < 1 neighbouring altered diorite. Accordingly, the Baba Ali profile, from the quartz syenite to the middle part of the exoskarn, demonstrates chiefly alkaline conditions of formation, with a gradual change to acidic towards the altered diorite host rocks. Utilising three parameters, Ce/Ce*, Eu/Eu* and (Pr/Yb)n, in different minerals implies that the hydrothermal fluids responsible for epidote and garnet were mostly of magmatic origin and for magnetite, actinolite and phlogopite these were of magmatic origin with low REE concentration or meteoric water involved.

  4. Mineral inclusions and SHRIMP U-Pb dating of zircons from the Alamas nephrite and granodiorite: Implications for the genesis of a magnesian skarn deposit

    Science.gov (United States)

    Liu, Yan; Zhang, Rongqing; Zhang, Zhiyu; Shi, Guanghai; Zhang, Qichao; Abuduwayiti, Maituohuti; Liu, Jianhui

    2015-01-01

    Extending approximately 1300 km and located in the Western Kunlun Mountains, the Hetian nephrite belt is the largest nephrite belt in the world and contains approximately 11 major deposits and more than 20 orebodies including the Alamas deposit. Hetian nephrite deposits can be classified as Mg-skarn deposits with Precambrian dolomitic marble host rock and green, green-white and white nephrite zones are distributed gradually in the zone of a granodiorite pluton. The green nephrite is mainly predominately composed of tremolite with generally minor to trace constituents of diopside, grossularitic garnet, actinolite and other minerals. Also green nephrite has higher content of TFe2O3, than green-white and white nephrites have. We subdivided the zircons from the green nephrites into four types, depending on their internal textures, mineral inclusions, and SHRIMP U-Pb ages. Type I zircons are round instead of idiomorphic in shape and lack obvious zoning. Type II and IV zircons have broad, clear oscillatory zoning and are hypidiomorphic or idiomorphic in shape; they contain inclusions of diopside, tremolite, chlorite and calcite. Most Type III zircons are narrow rims (highly luminous brightness and no zoning. Both Type I and Type II zircons have individual ages of 411 to 445 Ma and Type IV zircons have younger ages (388 to 406 Ma). Among the concordant ages, 425.7 ± 5.8 Ma and 420.0 ± 9.9 Ma for the QYZr1 and QYZr2 are consistent within error, with the 418.5 ± 2.8 Ma of the Alamas granodiorite formation age and the maximum age of the Alamas nephrite deposit. The partially recrystallization of zircons during skarn formation possibly lead to some younger individual ages (406.5 to 308 Ma). In the Western Kunlun Mountain, both Buya granite and Alamas grandiorite are high Ba-Sr granites and crystallized in Western Kunlun Orogen. The Buya granite formed at about 430 Ma in a post-orogenic tectonic environment. Considering Alamas granodiorite formed at about 12 Ma younger than

  5. Study of REE behaviors, fluid inclusions, and O, S stable Isotopes in Zafar-abad iron skarn deposit, NW Divandarreh, Kordestan province

    Directory of Open Access Journals (Sweden)

    Mehrdad Barati

    2014-10-01

    Full Text Available Introduction The Zafar-abad iron ore deposit, situated in the NW part of Divandarreh (lat. 36°01'14" and long. 46°58'22". The ore body is located on the northern margin of the Sanandaj-Sirjan igneous metamorphic zone. The Zafar-abad Fe-skarn deposit is one of the important, medium- size mineral deposits in western Iran. REE patterns of skarn magnetite were among others studied in Skarn deposit by (Taylor, 1979 Hydrothermal alteration and fluid-rock interaction significantly affect total contents of REE and their patterns in fluids. Moreover, fractionation of REE by chemical complication, adsorption effects and redox reactions are characteristic processes determining REE behavior during crystallization. Stable isotope data for oxygen and sulfur have been widely used with great success to trace the origin and evolution history of paleo-hydrothermal fluids of meteoric, magmatic, and metamorphic. Materials and methods The present study investigates REE and stable Isotope geochemistry of magnetite and pyrite in Zafar-abad deposit and temperature of trapped fluid inclusions based on geothermometry analysis. In order to study the major, trace and REE compositions of Zafar-abad magnetite, twelve samples were collected from surface of ore exposures. The emphasis during sampling was on ores with primary textures. Discussion The Zafar-abad district is situated in Mesozoic and Cenozoic sedimentary, meta-sedimentary and meta-igneous rocks in Sanandaj-Sirjan igneous metamorphic zone. Sedimentary sequences dominantly composed of calcareous and conglomerate rocks. Various meta-sedimentary rocks are intercalated with the sedimentary rocks, and comprise biotite and muscovite-rich schist, calc-schist, calc-silicate rock. Several distinct ductile tectonic fabrics have been identified around the Zafar-abad deposit. The main ore body at Zafar-abad is in the form of a roughly horizontal, discordant, lens to tabular-shaped body plunging 10° NW, where it appears to

  6. Genetic relationship of high-Mg dioritic pluton to iron mineralization: A case study from the Jinling skarn-type iron deposit in the North China Craton

    Science.gov (United States)

    Jin, Ziliang; Zhang, Zhaochong; Hou, Tong; Santosh, M.; Han, Liu

    2015-12-01

    The Jinling complex is spatially and temporally associated with the Jinling skarn-type iron deposit. The complex is composed of biotite diorite, hornblende diorite, monzonite and quartz diorite. U-Pb dating of zircons from the biotite diorite and monzonite using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) yields ages of 126 ± 1.9 Ma and 128 ± 1.4 Ma, respectively. The unaltered rocks in the complex are characterized by variable contents of SiO2 (54.6-65.3 wt.%), MgO (2.7-9.2 wt.%), total FeO (3.5-8.8 wt.%), Na2O + K2O (5.2-8.9 wt.%), high Mg# values (73-88), Cr (103-452 ppm) and Ni (49-212 ppm) contents. The altered monzonite has lower MgO (2.1-3.7 wt.%), total FeO (1.2-2.6 wt.%) and higher Na2O + K2O (8.5-9.9 wt.%) contents. The initial (87Sr/86Sr)t ranges from 0.70450 to 0.70555 and εNd(t) shows a range of -3.0 to -8.0. The geochemical characteristics suggest that the primary magma witnessed the interaction between the partial melts of relatively oxidized delaminated ancient crust and mantle peridotite. Fractional crystallization and crustal contamination during the magmatic ascent and emplacement are also indicated. The Jinling skarn-type Fe deposit is of hydrothermal origin and the Fe enrichment can be ascribed to multiple factors. The delaminated ancient crustal source contributed to the high oxygen fugacity of the primary magma. Two-stage Fe-enrichment process involving fractional crystallization of the primary magma giving rise to high Cl and Fe contents in the magmatic hydrothermal fluid and later Fe-leaching process, accounts for the high-grade ore bodies.

  7. Zircon SHRIMP U-Pb Dating of the Monzonitic Granite from Kateba’ asu Au-Cu Deposit and Its Geological Implications in XinJing%新疆卡特巴阿苏金铜矿区二长花岗岩锆石SHRIMP U-Pb年龄及地质意义

    Institute of Scientific and Technical Information of China (English)

    邢令; 杨维忠; 藏梅; 林泽华; 陈威

    2015-01-01

    新疆卡特巴阿苏金铜矿床是在那拉提中天山构造带内发现的首个特大型金铜矿床,矿床赋存于二长花岗岩体的脆性断裂破碎带内。通过对二长花岗岩的锆石进行SHRIMP U-Pb测年,获得25粒锆石加权平均值为(359.3±5.3)Ma,表明该岩体侵位时间为晚泥盆世末期,同时限定了卡特巴阿苏金矿金铜矿床的形成年龄上限为(359.3±5.3)Ma。%The Au-Cu deposit of Kateba’asu Located in the nalati tectonic belt of Western Tianshan Mountains was the first discovered superlarge Au deposit in nalati tectonic belt.The ore-controlling strata is brittle fracture zone in monzonit-ic granite,zircon SHRIMP U-Pb dating of monzonitic granite intrusion yield apparent 206Pb/238U age of(359.3 ± 5.3)Ma. Meanwhile,the age limits the deposit formed in the end of late Devonian.

  8. Microstructure-property relationship in highly ductile Au-Cu thin films for flexible electronics

    International Nuclear Information System (INIS)

    Research highlights: → Nanocrystalline AuCu alloy thin films were co-sputter deposited on polyimide. →In situ SEM tensile tests were performed. → The most ductile films did not crack up to 30% applied tensile strain. → Deformation localizes in periodic and oriented shear bands. → Shear bands are the precursors for cracks. - Abstract: The new and fast emerging field of flexible electronic devices requires highly ductile materials. Deposition of thin metal films on flexible substrates is a suitable method to create highly ductile interconnects. In this study, thin films consisting of a graded composition of Au-Cu were co-deposited by direct-current magnetron sputtering on polyimide (Kapton) substrate for in situ SEM tensile testing, while silicon wafer supported thin film spreads were characterized by nanoindentation, XRD and EDX. Substrate quality turned out to be extremely important for strain delocalization to allow for uniform deformation characterized by high ductility. No cracking was observed up to the maximal strain of 30% for films consisting of pure gold and alloys with a low copper content up to 10 at.%, while cracking was more prevalent in films with higher copper contents and with applied heat treatment. In the most ductile thin films shear bands are the precursors of ductile cracks.

  9. Structured Pd-Au/Cu-fiber catalyst for gas-phase hydrogenolysis of dimethyl oxalate to ethylene glycol.

    Science.gov (United States)

    Zhang, Li; Han, Lupeng; Zhao, Guofeng; Chai, Ruijuan; Zhang, Qiaofei; Liu, Ye; Lu, Yong

    2015-07-01

    Galvanic co-deposition of 0.5 wt% Au and 0.1 wt% Pd on a microfibrous-structure using 8 μm Cu-fibers delivers a Pd-Au/Cu-fiber catalyst, which is highly active, selective and stable for the hydrogenolysis of dimethyl oxalate to ethylene glycol. Au and Pd synergistically promote the hydrogenolysis activity of Cu(+) sites, while Au also critically stabilizes Cu(+) sites to prevent deep reductive deactivation. PMID:26040855

  10. Electrical characteristics of vapor deposited amorphous MoS{sub 2} two-terminal structures and back gate thin film transistors with Al, Au, Cu and Ni-Au contacts

    Energy Technology Data Exchange (ETDEWEB)

    Kouvatsos, Dimitrios N.; Papadimitropoulos, Georgios; Spiliotis, Thanassis; Vasilopoulou, Maria; Davazoglou, Dimitrios [NCSR Demokritos, Institute of Nanoscience and Nanotechnology, Attikis (Greece); Barreca, Davide [CNR-IENI, Padova (Italy); Department of Chemistry, Padova University (Italy); INSTM, Padova (Italy); Gasparotto, Alberto [Department of Chemistry, Padova University (Italy); INSTM, Padova (Italy)

    2015-07-15

    Amorphous molybdenum sulphide (a-MoS{sub 2}) thin films were deposited at near room temperature on oxidized silicon substrates and were electrically characterized with the use of two-terminal structures and of back-gated thin film transistors utilizing the substrate silicon as gate. Current-voltage characteristics were extracted for various metals used as pads, showing significant current variations attributable to different metal-sulphide interface properties and contact resistances, while the effect of a forming gas anneal was determined. With the use of heavily doped silicon substrates and aluminum backside deposition, thin film transistor (TFT) structures with the a-MoS{sub 2} film as active layer were fabricated and characterized. Transfer characteristics showing a gate field effect, despite a leakage often present, were extracted for these devices, indicating that high mobility devices can be fabricated. SEM and EDXA measurements were also performed in an attempt to clarify issues related to material properties and fabrication procedures, so as to achieve a reliable and optimized a-MoS{sub 2} TFT fabrication process. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Isotopic Geochemistry of the Tonglushan Cu-Fe Skarn Type Deposit in Hubei Province%湖北铜绿山矽卡岩型铜铁矿床同位素地球化学研究

    Institute of Scientific and Technical Information of China (English)

    王彦博; 顾雪祥; 张宗保; 董树义

    2011-01-01

    Located in the southeastern Hubei metallographic province of the Middle-Lower Yangtze River Fe-Cu metallogenic belt, the Tonglushan Cu-Fe deposit is a typical skarn Cu-Fe deposit in the southeastern Hubei metallographic province. The ore bodies, in the lenticular forms, occur in the contact zone between the marble of 4th -7th Members of the Lower Triassic Daye Group. The ore-forming process can be divided roughly into five stages; the anhydrous skarn stage( I ) , the hydrous skarn stage( II ), the oxide stage( III), the quartz-sul-fide stage(IV) and the carbonate stage( V ). Ore minerals mainly include magnetite, chalcopyrite and hematite; gangue mineral include mainly garnet, quartz and carbonate mineral. This paper mainly studied sulfur, hydrogen , oxygen, carbon, lead isotopic compositions and analyzed the indicative meaning of these isotopes to chemistry of the ore fluids and the sources of the ore-forming materials and intrusions. The composition of H and 0 isotopes shows that ore fluids were most likely composed of magmatic water mixed with limited meteoric water at the early ore-forming stage and mixed with much meteoric water at the late ore-forming stage. Sulfur and carbon isotopic data suggest that the ore forming materials were mainly derived from the deep magma and the carbon was derived subordinately from the dissolution of wall rocks or the mantle. The Pb isotopic composition of ore sulfides are stable and they are ordinary common lead. Ore lead was derived from mantle magma which was subjected to the hybridization of crust materials in the course of intruding upward.%湖北铜绿山铜铁矿床处于长江中下游铁铜成矿带西部鄂东成矿区内,是鄂东南地区典型的矽卡岩型铜铁矿床.矿体呈透镜状产于下三叠统大冶群第3至第7岩性段大理岩与铜绿山岩体的接触带.矿床成矿过程大致划分为干矽卡岩阶段(Ⅰ)、湿矽卡岩阶段(Ⅱ)、氧化物阶段(Ⅲ)、石英硫化物阶段(Ⅳ)和碳酸

  12. Solidification of Au-Cu-Si alloys investigated by a combinatorial approach

    International Nuclear Information System (INIS)

    Composition libraries of Au-Cu-Si films comprising 800 composition patches were fabricated through co-sputtering deposition from elemental targets. The gold composition varies between 47% (compositions are in atomic percentage) and 81%, copper between 8% and 40%, and silicon between 6% and 36% within the library. We designed and used a high-throughput optical characterization method to detect melting and solidification based on changes in the film’s contrast; further microscopy characterization reveals the microstructure. This approach reveals the composition dependence of the nucleation temperature and primary phase, which allows us to draw conclusions about glass forming ability and to identify bulk metallic glass forming compositions. Our solidification results suggest that the best glass forming composition coincides with the composition at which a transition from one primary phase to another occurs. We show that in general this transition is not at the eutectic composition but at the lowest nucleation temperature.

  13. The formation of heterointerface defects in Au/Cu films on Si substrates under direct current in a vacuum ultraviolet environment.

    Science.gov (United States)

    Yan, Kai; Yao, Wenqing; Yang, Liping; Cao, Jiangli; Zhao, Yuanyuan; Zhao, Lixia; Zhu, Yongfa

    2016-02-01

    Au/Cu metallic films were deposited on p-Si(100) substrates with and without an Au upper layer by magnetron sputtering. The defect formation and nanoscale interfacial evolution at the Au/Cu and Cu/Si interfaces were studied by using Auger electron spectroscopy (AES) and high resolution transmission electron microscopy (HRTEM). The results showed that an increase in defects at the heterointerfaces and in the surface layer was induced by the effect of a direct current (DC) in a vacuum ultraviolet (UV) environment, which could provide more channels for the removal of atoms. The directed migration of atomic clusters in the films was caused by the effect of the DC, which also aggravated the defects' expansion and led to the formation of Au-Cu intermetallic compounds (IMCs). In addition, the voids formed at the interface between the Au/Cu films and the Si substrates were found to be mainly related to the generation of the material Au2Cu3. PMID:26778294

  14. Themal Expansion and Magnetostriction of YbAuCu4

    Science.gov (United States)

    Tkeuchi, Tetsuya; Hirose, Yusuke; Tsunoda, Ryoma; Honda, Fuminori; Settai, Rikio

    Precise thermal expansion and magnetostriction measurements were performed on the heavyfermion compound YbAuCu4 in order to examine the crossover valence transition at TV which was proposed by the nuclear magnetic resonance measurements. The temperature dependence of the thermal expansion coefficient α under magnetic fields shows a broad peak, which shifts to higher temperatures with increasing magnetic fields. The corresponding linear thermal expansion Δℓ/.ℓ parallel to the magnetic field of 7.0 T shows a marked decrease below about 10 K, indicating a contraction of sample length at low temperatures. These results are discussed in relation to the observed temperature dependence of the nuclear quadrupole frequency νQ under magnetic fields.

  15. Reflection seismic investigations in the Dannemora area, central Sweden: Insights into the geometry of polyphase deformation zones and magnetite-skarn deposits

    Science.gov (United States)

    Malehmir, Alireza; Dahlin, Peter; Lundberg, Emil; Juhlin, Christopher; SjöStröM, HâKan; HöGdahl, Karin

    2011-11-01

    The Bergslagen region is one of the most ore prospective districts in Sweden. Presented here are results from two nearly 25 km long reflection seismic profiles crossing this region in the Dannemora mining area. The interpretations are constrained by seismic wave velocity measurements on a series of rock samples, cross-dip analysis, prestack time migration, and swath 3-D imaging, as well as by other available geophysical and geological observations. A series of major fault zones is imaged by the seismic data, as is a large mafic intrusion. However, the most prominent feature is a package of east-dipping reflectors found east of the Dannemora area that extend down to at least 3 km depth. This package is associated with a polyphase, ductile-brittle deformation zone with the latest ductile movement showing east-side-up or reverse kinematics. Its total vertical displacement is estimated to be in the order of 2.5 km. Also clearly imaged in the seismic data is a steeply dipping reflector near the Dannemora mine that extends down to a depth of at least 2.2 km. The geological nature of this reflector is not known, but it could represent either a fluid-bearing fault zone or a deep-seated iron deposit, making it an important target for further detailed geophysical and geological investigations.

  16. Au-Cu2O core-shell nanowire photovoltaics

    International Nuclear Information System (INIS)

    Semiconductor nanowires are among the most promising candidates for next generation photovoltaics. This is due to their outstanding optical and electrical properties which provide large optical cross sections while simultaneously decoupling the photon absorption and charge carrier extraction length scales. These effects relax the requirements for both the minority carrier diffusion length and the amount of semiconductor needed. Metal-semiconductor core-shell nanowires have previously been predicted to show even better optical absorption than solid semiconductor nanowires and offer the additional advantage of a local metal core contact. Here, we fabricate and analyze such a geometry using a single Au-Cu2O core-shell nanowire photovoltaic cell as a model system. Spatially resolved photocurrent maps reveal that although the minority carrier diffusion length in the Cu2O shell is less than 1 μm, the radial contact geometry with the incorporated metal electrode still allows for photogenerated carrier collection along an entire nanowire. Current-voltage measurements yield an open-circuit voltage of 600 mV under laser illumination and a dark diode turn-on voltage of 1 V. This study suggests the metal-semiconductor core-shell nanowire concept could be extended to low-cost, large-scale photovoltaic devices, utilizing for example, metal nanowire electrode grids coated with epitaxially grown semiconductor shells

  17. Large extrinsic spin Hall effect in Au-Cu alloys by extensive atomic disorder scattering

    Science.gov (United States)

    Zou, L. K.; Wang, S. H.; Zhang, Y.; Sun, J. R.; Cai, J. W.; Kang, S. S.

    2016-01-01

    Spin Hall angle, which denotes the conversion efficiency between spin and charge current, is a key parameter in the pure spin current phenomenon. The search for materials with large spin Hall angle is indeed important for scientific interest and potential application in spintronics. Here the large enhanced spin Hall effect (SHE) of Au-Cu alloy is reported by investigating the spin Seebeck effect, spin Hall anomalous Hall effect, and spin Hall magnetoresistance of the Y3F e5O12 (YIG)/A uxC u1 -x hybrid structure over the full composition. At the near equiatomic Au-Cu composition with maximum atomic disorder scattering, the spin Hall angle of the Au-Cu alloy increases by two to three times together with a moderate spin diffusion length in comparison with Au. The longitudinal spin Seebeck voltage and the spin Hall magnetoresistance ratio also increase by two to three times. More importantly, no evidence of anomalous Hall effect is observed in all YIG/Au-Cu samples, in contrast to the cases of other giant SHE materials Pt(Pd), Ta, and W. This behavior makes Au-Cu free from any suspicion of the magnetic proximity effect involved in the hybrid structure, and thus the Au-Cu alloy can be an ideal material for pure spin current study.

  18. 青海野马泉矽卡岩铁锌多金属矿区侵入岩、交代岩及矿化蚀变特征%Characteristics of intrusive rock, metasomatites, mineralization and atteration in Yemaquan skarn Fe-Zn polymetallic deposit, Qinghai Province

    Institute of Scientific and Technical Information of China (English)

    刘建楠; 丰成友; 赵一鸣; 李大新; 肖晔; 周建厚; 马永寿

    2013-01-01

    The Yemaquan Fe-Zn polymetallic deposit is located at the junction belt between Chaidamu basin and Qi-mantag area, Qinghai. There are some Hercynian and Indosinian intrusive rocks exposed in the ore dtstrict. The strata in the ore district are mainly Sijiaoyanggou Group. The skarn mainly occurs within the carbonate rocks and igneous conversion boundaries. The skarn minerals are mainly garnet, clinopyroxene, vesuvianite and epi-dote. Metallic minerals mainly include magnetite, chalcopyrite, galena, sphalerite and pyrrhotite. Based on the detailed field geological investigation and the observation of geological sections and drill cores, the authors studied the petrogeochemical characteristics and mineralization of this deposit. The petrochemistry of diorite is characterized by low SiO2 (51.90% ~ 59.03%), high MgO (2.04% ~3.44%) and TFeO (11.39% ~ 11.67%), rich REE (318.57 x 10~6 -327.76 x 10~6), and low LREE/HREE ratios (7.36-7.48). The monzonitic granite is characterized by high SiO2>(77.36% ~77.41%), low MgO (0.04% ~0.10%), low TFeO (0.76% ~1.08%), and high LREE/HREE ratios (9.14-9.37). The diopside-alkali metasomatites show stronger Eu negative anomaly (Eu = 0.07-0.52) and lower LREE/HREE ratios(3.19-7.87)than its original rock. The diopside-sodic metasomatites have low MgO (0.36% ~ 0.92%), high TFeO (3.05% ~ 8.13%) than its original rock. The skarn from Yemaquan deposit can be further divided into two types: calcic skarn and magnesian skarn. The calcic skarn is mainly distributed in the contact zone and consists of garnet and clinopyroxene. The clinopyroxenes distributed near the intrusion have high content of diposide end-member, and the garnet has more andradite end-members at the edge. According to the mineral composition and mineral inter-growth association, the authors have inferred that the diorite possesses remarkable mineralization potentiality, and calcic skarn was formed at an oxidation stage, whereas the magnesian skarn was formed in a reduction state

  19. Competitive diffusion of gold and copper in Cu/Au/Si and Au/Cu/Si annealed systems

    International Nuclear Information System (INIS)

    Full text.Thermal evaporation is used to deposit Au/Cu and Cu/Au bilayers on monocrystallin silicon substrates. The layers composition and surface morphology are performed as function of annealing temperature in the temperature range between 200 and 400 degre celsius using X-Ray diffraction, Rutherford backscattering spectroscopy and scanning electron microscopy. Independantly to the sequence of copper and gold deposition, Cu3Si and Cu4Si copper silicides result to the interdiffusion and reaction at the different interfaces. The 1000 A and 1200 A thicknesses of gold and copper diffusion barriers are insufficient to prevent the diffusion of copper and gold atoms respectively after an annealing of only 200 degre celsius

  20. Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit, Southeastern Hubei Province%Laser Ablation ICP-MS Titanite U-Th-Pb Dating of the Tonglushan Cu-Fe-Au Skarn Deposit,Southeastern Hubei Province

    Institute of Scientific and Technical Information of China (English)

    LI Jian-wei; DENG Xiao-dong; ZHOU Mei-fu; LIU Yong-sheng

    2009-01-01

    @@ Titanite (CaTi_2SiO_5) is an important accessory mineral not only in magnatic and metamorphic rocks,but also commonly in hydrothermal mineral deposits.It incorporates appreciable amounts (usually 10 ×10~(-6) s to 100 × 10~(-6) s) of U and Th into its structure and has a closure temperature of Pb diffusion higher than 660 ~ 700 ℃ (Scott and St-Onge, 1995),making it an ideal U-Th-Pb geochronometer.

  1. Multi-information-based metallogenic prediction of skarn-type copper polymetallic deposit in the middle segment of Nanjing-Zhenjiang Mesozoic magmatic belt%宁镇中段夕卡岩型铜多金属矿床多元信息成矿预测初步研究

    Institute of Scientific and Technical Information of China (English)

    张术根; 余旭辉; 徐莺

    2011-01-01

    宁镇中段铜多金属矿床主要为接触交代型矿床.文章以地质环境和成矿规律研究为基础,采用逻辑信息法综合提取地质、遥感、地球物理和地球化学多层次成矿预测信息,构建逻辑信息法成矿预测要素组合.并以此为指导,按照地质成矿条件有利程度、物化探异常强度与规模、环形构造发育程度、遥感解译蚀变显现强度与规模,进行综合判别确定成矿有利位置,圈定区内夕卡岩型矿床重点找矿靶区.%In the middle segment of Nanjing-Zhenjiang Mesozoic magmatic belt, the copper polymetallic deposits are dominated by contact metasomatic type. Based on the geological environment and metallogenic regularity the logical-information method is used to extract multi-metallogenic prediction (geological,remote-sensing, geophysical and geochemical) information of skarn-type cooper polymetallic ores. With this method and comprehensively analyzing the favorable degree of geological metallogenetic conditions,intensity and scale of geophysical-geochemical anomalies, development degree of circular structure, intensity and scale of RS-interpretation alteration, the favorable positions of mineralization are determined, and the key prospecting target area of skarn-type copper deposits in the study area are also delineated. Finally,the potential of the key prospecting target area is discussed in detail.

  2. 鄂东南地区程潮大型矽卡岩型铁矿区岩体成因探讨%Genesis of the Intrusive Rocks in the Chengchao Large Skarn Iron Deposit,Southeastern Hubei Province

    Institute of Scientific and Technical Information of China (English)

    李伟; 谢桂青; 姚磊; 朱乔乔; 孙洪涛; 王建; 王小雨

    2014-01-01

    The Chengchao iron deposit is the largest skarn iron deposit in the southeastern Hubei ore cluster,but the genesis of the intrusive rocks is poorly constrained.In this contribution,mineralogy, geochemistry and Sr Nd Pb isotope of different type intrusive rocks have been studied.The biotite in the granite,quartzmonzonite porphyry and diorite is high in Mg contents,indicating that they derived from the mixture of mantle and crust material.The oxygen fugacity of the primary biotite in the granite and quartzmonzonite porphyry associated with the iron mineralization is high,indicating that the granite and quartzmonzonite porphyry are more favorable for the iron mineralization.Different types of intrusive rocks dominantly exhibit high K2 O content and metaluminous,and characterized by enrichment in the large iron lithophile elements(e.g.Rb,Ba and K)and light rare earth elements,and depletion in the high field elements(e.g.Nb,Ta and Ti).They have moderately high initial Sr((87 Sr/86 Sr)i =0.705 0 0.709 1)and negtiveεNd (εNd (t)=-14.1 6 -6.95),and ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb are 17.636 18.91 9,15.45 1 15.613,37.833 39.556 respectively.Viewed comprehensively from mineralogical characteristics of minerals in and geochemical and Sr Nd Pb isotopic features of intrusive rocks,it can be concluded that the intrusive rocks in the deposit are originated from the partial melting of an enriched mantle source,and then followed by significant contamination of the lower crust material during the evolution of magma.140 Ma diorite probably contains more mantle components than the granite and quartz monzonite porphyry of 128 Ma.The average zircon saturation temperatures in the granite and quartz monzonite porphyry are 783℃ and 788℃,respectively,similar to that for the diorite (765℃).%湖北程潮铁矿是鄂东南矿集区内最大的矽卡岩型铁矿床。为了系统研究矿区内不同侵入体的成因,对程潮矿区内不同时代的侵入体进

  3. Diffraction profile change in Au-Cu-Zn alloy with aging

    International Nuclear Information System (INIS)

    The interesting property rubber-like behavior is observed in Au-Cu-Zn alloy. The behavior appears after aging the alloy in a martensitic state though the behavior does not appear without aging. The profile measurements from several scans were made in a Au-Cu-Zn alloy and integrated intensities computed. The profile measurements perpendicular to the (anti 128) plane were also done on the anti 130 reflection. A diffuse maximum, which changes significantly with aging time, was observed along [ anti 128]*. These observations suggest that a local atomic rearrangement of the (anti 128) plane occurs with aging. (orig.)

  4. K-Ar and Rb-Sr minerals ages of skarns and associated metabasites and leptites in the Hjulsjoe area of the Bergslagen ore province, central Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Moorman, A.C.; Andriessen, P.A.M.; Boelrijk, N.A.I.M.; Hebeda, E.H.; Priem, H.N.A.; Verdurmen, E.A.T.; Verschure, R.H. (Z.W.O. Laboratorium voor Isotopen-Geologie, De Boelaan (Netherlands)); Oen, I.S. (Universiteit van Amsterdam (Netherlands)); Wiklander, U. (Sveriges Geologiska Undersoekning, Uppsala (Sweden))

    1982-10-25

    K-Ar analyses of 20 hornblendes from skarns and associated metabasites in the Hjulsjoe area of the Bergslagen ore province, central Sweden, define an age of 1.83+-0.05 Ga. This age is interpreted in terms of the geological relationships as signalling a period of skarn-formation and metamorphism along with episodes of shearing and basic dike intrusion. Following the hypothesis that the skarn ores were formed by sea-floor hydrothermal metamorphism, this age should also be attributed to the deposition of the enclosing volcano-sedimentary leptite-haelleflinta sequence and the injection and extrusion of basic magma. Analyses of 13 biotites from the skarns and enclosing metavolcanic leptites produce K-Ar and Rb-Sr ages of 1.69+-0.05 Ga and 1.65+-0.04 Ga, respectively; these are related to an episode of mild crustal heating associated with nearby post-orogenic granite intrusion dated at 1.70 Ga.

  5. Au-CuO core-shell nanoparticles design and development for the selective determination of Vitamin B6

    International Nuclear Information System (INIS)

    Highlights: • Seed mediated growth of Au-CuO core-shell nanoparticle. • Au-CuO core-shell nanoparticle provided good peak current for pyridoxine. • Au-CuO/MWCNTs/GC exhibited excellent vitamin B6 peak separation with other vitamin. - Abstract: This paper reports the synthesis of gold (core)-copper oxide (shell) nanoparticles using a simple seed mediated growth method. Pre-synthesized Au nanoparticles were used as seed materials for copper oxide shell growth, which were shown to be effective for Au-CuO core-shell formation. The novelty of this assembly strategy is that the exploitation of the Cu-ligand, which is thermolyzed on the Au nanoseed surface, results in the formation of CuO. Au-CuO core-shell nanoparticles were characterized by UV-visible spectroscopy, high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). The as prepared Au-CuO was used to fabricate a Au-CuO/MWCNTs/GC-modified electrode, which was applied to Vitamin B6 (pyridoxine) determination by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The MWCNTs enhance the pyridoxine oxidation rate by increasing the peak current with Au-CuO, hence pyridoxine oxidized lower operating potentials. The Au-CuO/MWCNTs/GC-modified electrode showed excellent electrochemical performance towards pyridoxine (PY) in the presence of other typical vitamins, such as riboflavin, ascorbic acid and uric acid. The linear calibration graph was obtained over the PY concentration range of 0.79 μM–18.4 μM and the detection limit (S/N = 3) was 0.15 μM. The Au-CuO/MWCNTs/GC-modified electrode showed good stability, repeatability and recovery of real sample analysis

  6. Size Control and Growth Process Study of Au@Cu2O Particles.

    Science.gov (United States)

    Wang, Yuyuan; Zheng, Min; Liu, Shengnan; Wang, Zuoshan

    2016-12-01

    Au@Cu2O cuboctahedron with gold triangular nanoplate core and Cu2O shell was synthesized by a chemical method. X-ray diffraction (XRD) and transmission electron microscopy (TEM) tests demonstrated that the as-synthesis samples were consisted of gold triangular nanoplate core and Cu2O shell, and both of them were in good crystallization. The effective size control of the particles could be realized by controlling the amount of Au cores added in the synthetic process and Au@Cu2O particles with different shell thickness could be synthesized. The decrease of Cu2O shell thickness had a great difference in the optical performance, including blue shift of the resonant peaks and enhanced absorption intensity. The growth process from rough sheet structure to cuboctahedron was also explored. The results of photocatalytic degradation experiment showed that Au@Cu2O particles showed much better photocatalytic performance than that of pure Cu2O. The improved photocatalytic property of the Au@Cu2O particles was attributed to the comprehensive effect of the enhanced visible-light absorption and high separation rate of electron-hole pairs. PMID:27613067

  7. Band Structure and Optical Properties of Ordered AuCu3

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Lengkeek, H. P.

    1979-01-01

    initio band structure obtained by the relativistic linear muffin-tin orbitals method. The band calculation reveals that ordered AuCu3 has distinct copper and gold d bands positioned in and hybridizing with an s band common to copper and gold. The calculated state density is found to be in good agreement...

  8. AuCu@Pt Nanoalloys for Catalytic Application in Reduction of 4-Nitrophenol

    Directory of Open Access Journals (Sweden)

    Sadia Mehmood

    2016-01-01

    Full Text Available To enhance and optimize nanocatalyst ability for nitrophenol (4-NP reduction reaction we look beyond Au-metal nanoparticles and describe a new class of Au nanoalloys with controlled composition for core of AuCu-metals and Pt-metal shell. The reduction of 4-NP was investigated in aqueous media spectroscopically on 7.8 nm Au nanospheres (AuNSs, 8.3 nm AuCuNSs, and 9.1 nm AuCu@Pt core-shell NSs in diameter. The rate constants of the catalyzed reaction at room temperature, activation energies, and entropies of activation of reactions catalyzed by the AuCu@Pt core-shell NSs are found to have different values to those of the pure metal NSs. The results strongly support the proposal that catalysis by nanoparticles is taking place efficiently on the surface of NSs. These core-shell nanocatalysts exhibited stability throughout the reduction reaction and proved that heterogonous type mechanisms are most likely to be dominant in nanoalloy based catalysis if the surface of the NSs is not defected upon shell incorporation.

  9. Surface plasmon resonance of two segmented Au Cu nanowires in polycarbonate template

    OpenAIRE

    Babaei, F; Azarian, A.

    2013-01-01

    Two segmented gold copper nanowires were grown inside the pores of polycarbonate track (PCT) etched membranes from two separate solutions by electrodeposition method. Optical absorption spectra of two segmented Au Cu nanowires in PCT template were shown a surface plasmon- polariton peak appeared at about 900 nm for incident angle of theta = 65 degrees but for theta= 0 there are not any peaks in spectra.

  10. Study of thermodynamic properties of AuCu superlattice by the statistical moment method

    International Nuclear Information System (INIS)

    We have investigated the thermodynamic quantities of AuCu superlattice using the statistical moment method in the statistical physics. The free energy, thermal lattice expansion coefficients, mean-square atomic displacements, and specific heats at the constant volume and those at the constant pressure, Cv and Cp, are derived in closed analytic forms in terms of the power moments of the atomic displacements. The present analytic formulas including the anharmonic effects of the lattice vibration give the predicted values of these quantities.

  11. Calculating model of mass action concentrations for Ag-Au-Cu melts

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on phase diagrams and measured activities, the calculating model of mass action concentrations for heterogeneous melts Ag-Au-Cu was formulated. Calculated results agree with the improved results of recent research work.showing that the model formulated can reflect the structural characteristics of these melts. In this model, without the help of any empirical parameters, only three equilibrium constants are used, hence it is simple, lear, and favorable to the simplification of calculation.

  12. Delta97/95Mo in molybdenites from the Azegour skarn (Morocco)

    OpenAIRE

    Breillat, Noémie; Guerrot, Catherine; Négrel, Philippe; Marcoux, Eric

    2013-01-01

    Molybdenum (Mo) isotopes are frequently used to investigate ocean and lake (paleo-)redox conditions. In the frame of mineral ressources, only few studies have been performed regarding Mo-Re-Os isotopes. The aim of this study is to understand the source, processes and mobility of metals concentrations using Mo isotopes on molybdenites in different ore deposits. The present study focuses on the Azegour skarn (Morocco). Located in the High-Atlas, the Azegour site is one of the rare Mo-W-Cu explo...

  13. Mineralogy, geochemistry, and evolution of the Mivehrood skarn and the associated pluton, northwest Iran

    Science.gov (United States)

    Alirezaei, Saeed; Einali, Morteza; Jones, Peter; Hassanpour, Shohreh; Arjmandzadeh, Reza

    2016-04-01

    An Upper Miocene (9.12 ± 0.19 Ma; biotite 40Ar/39Ar) shallow pluton and numerous dykes and sills of felsic-intermediate compositions intruded the Upper Cretaceous, flysch-type sediments in the Mivehrood area, northwest Iran. The intrusions caused extensive thermal metamorphism and metasomatism, leading to the formation of hornfels and skarn. A massive skarn, 1-10 m thick, immediate to the intrusive contact, is bordered by a banded skarn, 100-400 m thick, that grades outward into hornfels and original sediments. The Mivehrood pluton is characterized by steep REE pattern, high Al2O3 (14.64-16.4 wt%) and Sr (380-786 ppm), and low MgO (1.3-3.4 wt%), Y (4.8-10.7 ppm), and Yb (0.35-0.95 ppm), characteristics typical of high-silica adakites. Skarn formation started with thermal metamorphism, followed by anhydrous prograde and hydrous retrograde stages. Prograde and retrograde mineral assemblages are developed in both skarns, represented by garnet-clinopyroxene-wollastonite and epidote-actinolite-scapolite-chlorite, respectively. Granditic F-bearing garnet dominates clinopyroxene in both skarns. The banded skarn contains minor scapolite of marialite composition. The calc-silicate mineral assemblages and the mineral chemistry allow the Mivehrood skarn to be classified as a calcic, oxidized skarn. Mass balance assessments suggest that Fe, Si, and S were significantly enriched, and Na, LILEs, and LREEs were strongly depleted, in the massive skarn. In the banded skarn, Na, K, Si, and S were enriched. Significant dehydration and carbon degassing occurred in both skarns. Stockworks, veins, and replacement bodies of pyrite ± chalcopyrite locally occur in the pluton and the dykes and in the skarns. The δ34SCDT values for the sulfides fall in a narrow range around 0.0 ‰, suggesting a magmatic source for sulfur and possibly the hydrothermal water and solutes involved in the skarn formation.

  14. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20150904An Fang(State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,China);Wang Juli Skarn Mineral Assemblage in Representative Ore Districts of Sayak Copper Orefield,Kazakhstan,and Its Genetic Implications(Mineral Deposits,ISSN0258-7106,CN11-1965/P,33(3),2014,p.521-540,

  15. A DFT-based genetic algorithm search for AuCu nanoalloy electrocatalysts for CO2 reduction

    DEFF Research Database (Denmark)

    Lysgaard, Steen; Mýrdal, Jón Steinar Garðarsson; Hansen, Heine Anton;

    2015-01-01

    Using a DFT-based genetic algorithm (GA) approach, we have determined the most stable structure and stoichiometry of a 309-atom icosahedral AuCu nanoalloy, for potential use as an electrocatalyst for CO2 reduction. The identified core–shell nano-particle consists of a copper core interspersed with...

  16. A Facile One-Pot Synthesis of Au/Cu2O Nanocomposites for Nonenzymatic Detection of Hydrogen Peroxide

    Science.gov (United States)

    Chen, Ting; Tian, Liangliang; Chen, Yuan; Liu, Bitao; Zhang, Jin

    2015-06-01

    Au/Cu2O nanocomposites were successfully synthesized by a facile one-pot redox reaction without additional reducing agent under room temperature. The morphologies and structures of the as-prepared products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The electrocatalytic performance of Au/Cu2O nanocomposites towards hydrogen peroxide was evaluated by cyclic voltammetry (CV) and chronoamperometry (CA). The prepared Au/Cu2O nanocomposite electrode showed a wide linear range from 25 to 11.2 mM ( R = 0.9989) with a low detection limit of 1.05 μM ( S/ N = 3) and high sensitivity of 292.89 mA mM-1 cm-2. The enhanced performance for H2O2 detection can be attributed to the introduction of Au and the synergistic effect between Au and Cu2O. It is demonstrated that the Au/Cu2O nanocomposites material could be a promising candidate for H2O2 detection.

  17. Alloy-dependent deformation behavior of highly ductile nanocrystalline AuCu thin films

    Energy Technology Data Exchange (ETDEWEB)

    Lohmiller, Jochen [Karlsruhe Institute of Technology, Institute for Applied Materials, P.O. Box 3640, 76021 Karlsruhe (Germany); Laboratory for Nanometallurgy, Department of Materials, ETH Zurich, Wolfgang-Pauli-Str. 10, 8093 Zurich (Switzerland); Spolenak, Ralph [Laboratory for Nanometallurgy, Department of Materials, ETH Zurich, Wolfgang-Pauli-Str. 10, 8093 Zurich (Switzerland); Gruber, Patric A., E-mail: patric.gruber@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, P.O. Box 3640, 76021 Karlsruhe (Germany)

    2014-02-10

    Nanocrystalline thin films on compliant substrates become increasingly important for the development of flexible electronic devices. In this study, nanocrystalline AuCu thin films on polyimide substrate were tested in tension while using a synchrotron-based in situ testing technique. Analysis of X-ray diffraction profiles allowed identifying the underlying deformation mechanisms. Initially, elastic and microplastic deformation is observed, followed by dislocation-mediated shear band formation, and eventually macroscopic crack formation. Particularly the influence of alloy composition, heat-treatment, and test temperature were investigated. Generally, a highly ductile behavior is observed. However, high Cu concentrations, annealing, and/or large plastic strains lead to localized deformation and hence reduced ductility. On the other hand, enhanced test temperature allows for a delocalized deformation and extended ductility.

  18. K-Ar and Rb-Sr minerals ages of skarns and associated metabasites and leptites in the Hjulsjoe area of the Bergslagen ore province, central Sweden

    International Nuclear Information System (INIS)

    K-Ar analyses of 20 hornblendes from skarns and associated metabasites in the Hjulsjoe area of the Bergslagen ore province, central Sweden, define an age of 1.83+-0.05 Ga. This age is interpreted in terms of the geological relationships as signalling a period of skarn-formation and metamorphism along with episodes of shearing and basic dike intrusion. Following the hypothesis that the skarn ores were formed by sea-floor hydrothermal metamorphism, this age should also be attributed to the deposition of the enclosing volcano-sedimentary leptite-haelleflinta sequence and the injection and extrusion of basic magma. Analyses of 13 biotites from the skarns and enclosing metavolcanic leptites produce K-Ar and Rb-Sr ages of 1.69+-0.05 Ga and 1.65+-0.04 Ga, respectively; these are related to an episode of mild crustal heating associated with nearby post-orogenic granite intrusion dated at 1.70 Ga. (Authors)

  19. A Au/Cu2O-TiO2 system for photo-catalytic hydrogen production. A pn-junction effect or a simple case of in situ reduction?

    KAUST Repository

    Sinatra, Lutfan

    2015-02-01

    Photo-catalytic H2 production from water has been studied over Au-Cu2O nanoparticle deposited on TiO2 (anatase) in order to probe into both the plasmon resonance effect (Au nanoparticles) and the pn-junction at the Cu2O-TiO2 interface. The Au-Cu2O composite is in the form of ∼10 nm Au nanoparticles grown on ∼475 nm Cu2O octahedral nanocrystals with (111) facets by partial galvanic replacement. X-ray Photoelectron Spectroscopy (XPS) Cu2p and Auger L3M4,5M4,5 lines indicate that the surface of Cu2O is mainly composed of Cu+. The rate for H2 production (from 95 water/5 ethylene glycol; vol.%) over 2 wt.% (Au/Cu2O)-TiO2 is found to be ∼10 times faster than that on 2 wt.% Au-TiO2 alone. Raman spectroscopy before and after reaction showed the disappearance of Cu+ lines (2Eu) at 220 cm-1. These observations coupled with the induction time observed for the reaction rate suggest that in situ reduction from Cu+ to Cu0 occurs upon photo-excitation. The reduction requires the presence of TiO2 (electron transfer). The prolonged activity of the reaction (with no signs of deactivation) despite the reduction to Cu0 indicates that the latter takes part in the reaction by providing additional sites for the reaction, most likely as recombination centers for hydrogen atoms to form molecular hydrogen. This phenomenon provides an additional route for enhancing the efficiency and lifetime of Cu2O-TiO2 photocatalytic systems, beyond the usually ascribed pn-junction effect.

  20. Significant enhancement in photocatalytic reduction of water to hydrogen by Au/Cu2 ZnSnS4 nanostructure.

    Science.gov (United States)

    Ha, Enna; Lee, Lawrence Yoon Suk; Wang, Jingchuan; Li, Fenghua; Wong, Kwok-Yin; Tsang, Shik Chi Edman

    2014-06-01

    Enhanced photocatalytic activities by Au core Novel Au/Cu2 ZnSnS4 core/shell nanoparticles (NPs) are synthesized for the first time via wet chemistry approach. The insertion of Au core into CZTS NPs dramatically enhances light absorption due to surface plasmon resonance effect, especially in the Vis-NIR region. Au/CZTS core/shell NPs show much higher photocatalytic activities for hydrogen evolution compared with other CZTS nanostructures. PMID:24644004

  1. Cu2O and Au/Cu2O Particles: Surface Properties and Applications in Glucose Sensing

    OpenAIRE

    Yu-Ho Won; Stanciu, Lia A.

    2012-01-01

    In this work we investigated the surface and facet-dependent catalytic properties of metal oxide particles as well as noble metal/metal oxide heterogeneous structures, with cuprous oxide (Cu2O) and Au/Cu2O being selected as model systems. As an example of application, we explored the potential of these materials in developing electrocatalytic devices. Cu2O particles were synthesized in various shapes, then used for testing their morphology-dependent electrochemical properties applied to the d...

  2. ARXPS and DFT studies of thermally induced Pb surface segregation on Au/Cu alloys

    Energy Technology Data Exchange (ETDEWEB)

    Völker, Edgar [Chemistry Department, University of Liverpool, Liverpool L69 7ZD (United Kingdom); Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires C1428EHA (Argentina); Williams, Federico J., E-mail: fwilliams@qi.fcen.uba.ar [Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires C1428EHA (Argentina); Jacob, Timo [Institute of Electrochemistry, Ulm University, Albert-Einstein-Allee 47, D-89081 Ulm (Germany); Schiffrin, David J. [Chemistry Department, University of Liverpool, Liverpool L69 7ZD (United Kingdom)

    2014-02-15

    Highlights: • Surface segregation of Pb impurities in AuCu alloys was studied by ARXPS and DFT. • ARXPS show a 23% surface coverage by Pb atoms. • DFT calculations predict a ¼ ML coverage of Pb atoms in the first atomic layer. • The results show that bulk systems are affected while leaving nanoparticulate systems unaffected. -- Abstract: Surface segregation of Pb has been studied using angle resolved X-ray Photoelectron Spectroscopy (ARXPS) and Density Functional Theory (DFT) modelling in a polycrystalline Au{sub 0.85}Cu{sub 0.15} alloy. Au surface enrichment was found in the alloy surface, whereas Pb surface enrichment was detected after annealing. ARXPS depth profiles show a 23% surface coverage by Pb atoms. DFT calculations predict an approximate coverage of ¼ monolayer (ML) of Pb atoms in the first atomic layer, consistent with the experimental results. The results presented here are an example of the importance of low concentration of impurities in determining the surface composition of bulk alloys.

  3. ARXPS and DFT studies of thermally induced Pb surface segregation on Au/Cu alloys

    International Nuclear Information System (INIS)

    Highlights: • Surface segregation of Pb impurities in AuCu alloys was studied by ARXPS and DFT. • ARXPS show a 23% surface coverage by Pb atoms. • DFT calculations predict a ¼ ML coverage of Pb atoms in the first atomic layer. • The results show that bulk systems are affected while leaving nanoparticulate systems unaffected. -- Abstract: Surface segregation of Pb has been studied using angle resolved X-ray Photoelectron Spectroscopy (ARXPS) and Density Functional Theory (DFT) modelling in a polycrystalline Au0.85Cu0.15 alloy. Au surface enrichment was found in the alloy surface, whereas Pb surface enrichment was detected after annealing. ARXPS depth profiles show a 23% surface coverage by Pb atoms. DFT calculations predict an approximate coverage of ¼ monolayer (ML) of Pb atoms in the first atomic layer, consistent with the experimental results. The results presented here are an example of the importance of low concentration of impurities in determining the surface composition of bulk alloys

  4. A DFT-based genetic algorithm search for AuCu nanoalloy electrocatalysts for CO₂ reduction.

    Science.gov (United States)

    Lysgaard, Steen; Mýrdal, Jón S G; Hansen, Heine A; Vegge, Tejs

    2015-11-14

    Using a DFT-based genetic algorithm (GA) approach, we have determined the most stable structure and stoichiometry of a 309-atom icosahedral AuCu nanoalloy, for potential use as an electrocatalyst for CO2 reduction. The identified core-shell nano-particle consists of a copper core interspersed with gold atoms having only copper neighbors and a gold surface with a few copper atoms in the terraces. We also present an adsorbate-dependent correction scheme, which enables an accurate determination of adsorption energies using a computationally fast, localized LCAO-basis set. These show that it is possible to use the LCAO mode to obtain a realistic estimate of the molecular chemisorption energy for systems where the computation in normal grid mode is not computationally feasible. These corrections are employed when calculating adsorption energies on the Cu, Au and most stable mixed particles. This shows that the mixed Cu135@Au174 core-shell nanoalloy has a similar adsorption energy, for the most favorable site, as a pure gold nano-particle. Cu, however, has the effect of stabilizing the icosahedral structure because Au particles are easily distorted when adding adsorbates. PMID:25924775

  5. Tellurides, selenides and Bi-mineral assemblages from the Río Narcea Gold Belt, Asturias, Spain: genetic implications in Cu-Au and Au skarns

    Science.gov (United States)

    Cepedal, A.; Fuertes-Fuente, M.; Martín-Izard, A.; González-Nistal, S.; Rodríguez-Pevida, L.

    2006-07-01

    Gold ores in skarns from the Río Narcea Gold Belt are associated with Bi-Te(-Se)-bearing minerals. These mineral assemblages have been used to compare two different skarns from this belt, a Cu-Au skarn (calcic and magnesian) from the El Valle deposit, and a Au-reduced calcic skarn from the Ortosa deposit. In the former, gold mineralization occurs associated with Cu-(Fe)-sulfides (chalcopyrite, bornite, chalcocite-digenite), commonly in the presence of magnetite. Gold occurs mainly as native gold and electrum. Au-tellurides (petzite, sylvanite, calaverite) are locally present; other tellurides are hessite, clausthalite and coloradoite. The Bi-bearing minerals related to gold are Bi-sulfosalts (wittichenite, emplectite, aikinite, bismuthinite), native bismuth, and Bi-tellurides and selenides (tetradymite, kawazulite, tsumoite). The speciation of Bi-tellurides with Bi/Te(Se + S) ≤ 1, the presence of magnetite and the abundance of precious metal tellurides and clausthalite indicate fO2 conditions within the magnetite stability field that locally overlap the magnetite-hematite buffer. In Ortosa deposit, gold essentially occurs as native gold and maldonite and is commonly related to pyrrhotite and to the replacement of löllingite by arsenopyrite, indicating lower fO2 conditions for gold mineralization than those for El Valle deposit. This fact is confirmed by the speciation of Bi-tellurides and selenides (hedleyite, joséite-B, joséite-A, ikunolite-laitakarite) with Bi/Te(+ Se + S) ≥ 1.

  6. 西秦岭谢坑矽卡岩型铜金矿床地质特征与矿区岩浆岩年代学研究%Geological characteristics and associated magmatic ages of the Xiekeng skarn-type Cu-Au deposit in the West Qinling terrane

    Institute of Scientific and Technical Information of China (English)

    郭现轻; 闫臻; 王宗起; 王涛; 吴发富; 付长垒; 候可军; 李继亮

    2011-01-01

    Magnetite and pyrrhotine ore is mainly massive, but chalcopyrite ore is either veinlike or disseminated. Cold mineralization commonly occurs within the carbonate-quartz veins. The distinctive altered zone is marked on the outcrops, which varies from potassic alteration, prophyllitization to skamization toward marble spatially. The skarn alteration, which occurs at the contact zone between gabbroic diorite and limestone, is closely related to mineraliztion. LA-ICP-MS zircon U-Pb dating of gabbro-diorite and amphibole-andesite yields concordant ages of 243. 8 ± l.Oma and 242. 1 ± 1. 2Ma respectively, which indicates that the Xiekeng skam-type deposit should be formed in the mid-Triassic. Our results indicate the Xiekeng deposit should be formed in the process of the Triassic arc-magmatism in the West Qinling terrane.

  7. 西藏嘎拉勒夕卡岩型金(铜)矿床地球化学特征与锆石的LA-ICP-MS定年及意义%Geochemical characteristics and zircon LA-ICP-MS U-Pb dating of Galale skarn gold(copper) deposit,Tibet and its significance

    Institute of Scientific and Technical Information of China (English)

    吕立娜; 崔玉斌; 宋亮; 赵元艺; 曲晓明; 王江朋

    2011-01-01

    嘎拉勒金(铜)矿床位于西藏班公湖—怒江缝合带的西段,为夕卡岩型金(大型)铜(小型)矿床。矿区主要岩石为巨斑状石英闪长岩、中细粒花岗闪长岩与闪长玢岩。该矿床岩石样品的REE分异程度较高,Eu呈弱负异常,w(Al2O3)为14.45%~15.84%,铝过饱和指数A/CNK为1.33~1.46,均大于1,表明为S型花岗岩。经微量元素的相关分析,该矿岩体为板内花岗岩,形成期接近于同碰撞期。锆石的LA-ICP-MS定年结果表明巨斑状石英闪长岩的年龄为(131±17)Ma,中细粒花岗闪长岩为(86.52±0.41)Ma,两个闪长玢岩的年龄分别为(88.59±0.45)和(88.09±0.41)Ma,其中巨斑状石英闪长岩为非成矿岩体,其测年数据代表了成岩时代下限;矿体只产在中细粒花岗闪长岩和闪长玢岩岩体与灰岩和粉砂岩夹硅质岩的接触带,为燕山期成矿。由测年结果可将该矿床的岩浆演化过程大致分为两个阶段,早白垩世非成矿岩体巨斑状石英闪长岩岩体的侵入和晚白垩世成矿岩体的形成,发生在白垩纪班公湖—怒江中特提斯洋构造演化的第4个阶段弧-陆碰撞造山阶段。%The Galale gold(copper) deposit is located in the west section of Bangong lake-Nujiang suture zone in Tibet.It is a gold(of large scale) and copper(of small scale) skarn deposit.There are mainly huge porphyritic quartz diorite,middle-fine grain granodiorite and diorite porphyrite in the mine area.The REE differential degree of rock sample in this ore deposit has a relatively higher value,and Eu negative anomaly is weak.The content of Al2O3 is 14.45%-15.84%.The aluminum supersaturation index(A/CNK) ranges between 1.33 and 1.46,which is greater than 1,indicating its being S-type granite.According to the analysis of trace elements,the magmatic body belongs to MPG.The forming stage is close to the collision stage.The result of zircon LA-ICP-MS dating indicates that the age of

  8. Formation of CuxAu1−x phases by cold homogenization of Au/Cu nanocrystalline thin films

    Directory of Open Access Journals (Sweden)

    Alona Tynkova

    2014-09-01

    Full Text Available It is shown, by using depth profiling with a secondary neutral mass spectrometer and structure investigations by XRD and TEM, that at low temperatures, at which the bulk diffusion is frozen, a complete homogenization can take place in the Cu/Au thin film system, which leads to formation of intermetallic phases. Different compounds can be formed depending on the initial thickness ratio. The process starts with grain boundary interdiffusion, which is followed by a formation of reaction layers at the grain boundaries that leads to the motion of the newly formed interfaces perpendicular to the grain boundary plane. Finally, the homogenization finishes when all the pure components have been consumed. The process is asymmetric: It is faster in the Au layer. In Au(25nm/Cu(50nm samples the final state is the ordered AuCu3 phase. Decrease of the film thicknesses, as expected, results in the acceleration of the process. It is also illustrated that changing the thickness ratio either a mixture of Cu-rich AuCu and AuCu3 phases (in Au(25nm/Cu(25nm sample, or a mixture of disordered Cu- as well as Au-rich solid solutions (in Au(25nm/Cu(12nm sample can be produced. By using a simple model the interface velocity in both the Cu and Au layers were estimated from the linear increase of the average composition and its value is about two orders of magnitude larger in Au (ca. 10−11 m/s than in Cu (ca. 10−13 m/s.

  9. Spin polarization of 23Mg in 24Mg + Au, Cu and Al collisions at 91 A MeV

    International Nuclear Information System (INIS)

    Spin polarization of beta-emitting fragment 23Mg(Iπ = 3/2+, Tl/2 = 11.3 s) produced through the projectile fragmentation process in 24Mg + Au, Cu and Al collisions has been observed at 91 A MeV. General trend in the observed momentum dependence of polarization is reproduced well qualitatively by a simple fragmentation model based on the participant-spectator picture, for heavy and light targets. However the polarization behavior differs from this model in terms of zero crossing momentum, which become prominent in the case of Cu target, where the polarization is not monotone function of the fragment momentum

  10. A DFT-based genetic algorithm search for AuCu nanoalloy electrocatalysts for CO2 reduction

    OpenAIRE

    Lysgaard, Steen; Mýrdal, Jón Steinar Garðarsson; Hansen, Heine Anton; Vegge, Tejs

    2015-01-01

    Using a DFT-based genetic algorithm (GA) approach, we have determined the most stable structure and stoichiometry of a 309-atom icosahedral AuCu nanoalloy, for potential use as an electrocatalyst for CO2 reduction. The identified core–shell nano-particle consists of a copper core interspersed with gold atoms having only copper neighbors and a gold surface with a few copper atoms in the terraces. We also present an adsorbate-dependent correction scheme, which enables an accurate determination ...

  11. 西藏班戈县多巴区矽卡岩型铁多金属矿床含矿花岗岩LA-ICP-MS锆石U-Pb定年、地球化学及意义%LA-ICP-MS zircon U-Pb dating and geochemical characteristics of ore-bearing granite in skarn-type iron polymetallic deposits of Duoba area,Baingoin County, Tibet, and their significance

    Institute of Scientific and Technical Information of China (English)

    定立; 赵元艺; 杨永强; 崔玉斌; 吕立娜

    2012-01-01

    Located in northwestern Baingoin County of Tibet, Duoba area is near the middle of Bangong Co-Nujiang River metallogenic belt with the distribution of a large number of skarn iron-copper polymetallic deposits (mineralization spots) characterized by good prospecting potential. Due to high elevations, traffic inconvenience and less mining, only a small amount of work has been carried out. This research is based on the systematic field geological survey, indoor petrographic and ore microscopic studies, zircon LA-ICP-MS U-Pb dating and analysis of major and trace elements. The authors chose Sousha skarn mineralization spot and Zai' a skarn iron polymetal-lic deposit to conduct researches on the relationship between the petrogenesis and the mineralization. There are mainly fine grained porphyritic granodiorites in Sousha area and fine grained granodiorites in Zai' a. Zircon' s LA-ICP-MS dating indicates that the age of the fine grained porphyritic granodiorite is 77.37 ± 0.55 Ma, whereas that of the fine grained granodiorite is 79.78 ± 0.99 Ma, suggesting products of late Cretaceous magma-tism. Their A/CNK values change between 0.78 and 1.29, and A/NK values change in the range of 0.88~ 1.51. The rocks belong to weakly peraluminous. They are enriched in big ion incompatible elements Rb, Th, U and K, and depleted in Nb, identical overall with the same period granite in Bangong Co-Nujiang River metallo-genicbelt. ∑ REE range from 199.82× 10-6 to 274.64× 10-6, LREE/HREE = 3.552~7.199, δEu=0.20 ~0.82, with medium negative Eu anomalies. These data indicate that the separation of plagioclase crystallization might have occurred in magmatic evolution processes. The ore-forming processes of Sousha and Zai'a rock bodies might have had something to do with the southward subduction of the Bangong Co-Nujiang Ocean Basin and acted as the products of magmatic activity after closing. With favorable iron and bismuth polymetallic ore-forming geological and geochemical

  12. Plasmon resonance enhanced photocatalysis under visible light with Au/Cu-TiO2 nanoparticles: Removal Cr (VI) from water as a case of study

    KAUST Repository

    Gondal, M. A.

    2013-12-01

    Gold modified copper doped titania (Au/Cu:TiO2) nanoparticles were synthesized by a modified sol gel method and characterized using XRD, optical and TEM based techniques. The as-prepared material contained anatase phase particles with quasi-spherical morphology, showing enhanced absorption in the visible region and low photoluminescence emission intensity. Photocatalytic reduction of Cr (VI) in aqueous suspension with the Au/Cu:TiO2catalyst under 532 nm laser radiation and a visible broad band lamp source yielded 96% and 45% removal, respectively, without any additives. The enhanced photocatalytic activity can be attributed to the improved plasmonic effect due to gold modification and the expanded visible absorption due to copper doping. Moreover a comparative study of the material properties and catalytic activity of TiO2, Cu-TiO2and Au/Cu-TiO2 was carried out. © 2013 by American Scientific Publishers.

  13. Compositional Change of the Au-Cu2Te Contact for Thin-Film CdS/CdTe Solar Cells

    Science.gov (United States)

    Uda, Hiroshi; Ikegami, Seiji; Sonomura, Hajimu

    1990-03-01

    The stability of thin-film CdS/CdTe solar cells with evaporated Au-Cu2Te contacts to the CdTe film has been investigated. A decrease in conversion efficiency due to an increase in series resistance was observed in the solar cells stored in air at room temperature for 120 days. The increase in series resistance is caused by an increase in contact resistance resulting from the compositional change in the Au-Cu2Te contact to the CdTe film.

  14. Sulfur isotope study of the Velardeña skarn (Zn-Pb), Durango, Mexico

    Science.gov (United States)

    Jimenez, A.

    2012-04-01

    Sulfur isotope study of the Velardeña skarn (Zn-Pb), Durango, Mexico Abigail Jimenez-Franco1*, Pura Alfonso Abella2, Carles Canet3, Eduardo González-Partida4 1 Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de México, Ciudad Universitaria, Delegación Coyoacán, 04510 México D.F., Mexico 2 Departament d'Enginyeria Minera i Recursos Naturals, Universitat Politècnica de Catalunya, Av de Les Bases de Manresa 61-73, 08242 Manresa. 3Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, Delegación Coyoacán, 04510 México D.F., Mexico 4Centro de Geociencias, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla 3001, 76230 Santiago de Querétaro, Qro., Mexico The Velardeña mining district is located in north-eastern part of the state of Durango, in northern of Mexico. The ore deposit is a lead-zinc, garnet-rich skarn developed at the contact between granite porphyry dikes (Eocene) and well-laminated limestones with interbedded chert (Albian-Cenomanian). A study of sulfur isotopes has been carried out in various sulfide minerals of the ores of Velardeña, in order to: (a) constrain the possible sources of sulfur and, therefore, better understand the sulfide mineralizing processes, and (b) to estimate the temperature of the ore-forming stage of the skarn. Sulfur isotope analyses were performed in 21 pure fractions of sulfide minerals of the ore mineralization (pyrite, chalcopyrite, sphalerite and galena). The mineral separation was performed using a series of sieves, and the purity of the samples was verified under a binocular microscope. Isotopic analyses were done on a Finnigan MAT Delta C flow elemental analyzer coupled to a TC-EA, according with the method of Giesemann et al. (1974). The δ34S values of the analyzed sulfides range mostly between -0.6 and +2.6 ‰ (relative to the CDT standard). These values are indicative of a magmatic source of sulfur. A single analysis falls

  15. Hollow Au-Cu2O Core-Shell Nanoparticles with Geometry-Dependent Optical Properties as Efficient Plasmonic Photocatalysts under Visible Light.

    Science.gov (United States)

    Lu, Biao; Liu, Aiping; Wu, Huaping; Shen, Qiuping; Zhao, Tingyu; Wang, Jianshan

    2016-03-29

    Hollow Au-Cu2O core-shell nanoparticles were synthesized by using hollow gold nanoparticles (HGNs) as the plasmon-tailorable cores to direct epitaxial growth of Cu2O nanoshells. The effective geometry control of hollow Au-Cu2O core-shell nanoparticles was achieved through adjusting the HGN core sizes, Cu2O shell thicknesses, and morphologies related to structure-directing agents. The morphology-dependent plasmonic band red-shifts across the visible and near-infrared spectral regions were observed from experimental extinction spectra and theoretical simulation based on the finite-difference time-domain method. Moreover, the hollow Au-Cu2O core-shell nanoparticles with synergistic optical properties exhibited higher photocatalytic performance in the photodegradation of methyl orange when compared to pristine Cu2O and solid Au-Cu2O core-shell nanoparticles under visible-light irradiation due to the efficient photoinduced charge separation, which could mainly be attributed to the Schottky barrier and plasmon-induced resonant energy transfer. Such optical tunability achieved through the hollow cores and structure-directed shells is of benefit to the performance optimization of metal-semiconductor nanoparticles for photonic, electronic, and photocatalytic applications. PMID:26954100

  16. Intermixing of thin metallic structures Au/Cu and Cu/Mo under the action of powerful ion beams

    International Nuclear Information System (INIS)

    Systems of thin metallic layers Au/Cu and Cu/Mo, subjected to the action of powerful nanosecond ion beam, have been studied. Fair intermixing with the formation of metastable alloys Cu85Au15 ordered structures of the type Cu3Au has been observed. It is found thet intermixing of copper (in the system Cu/Mo) occurs in the liquid phase at intensive evaporation of copper, the formation of the phase Cu2Mo2 taking place. The main role in the formation of the surface metastable alloys uppon intermixing of the layers by means of pulsed ion beams of nanosecond duration is played by a vapour-plasma state of the metal and its interaction with the substrate surface layer

  17. Re-Os molybdenite model age constraints on the petrogenesis of UTh-bearing late tectonic pegmatite and skarn mineralization in the southwestern Grenville Province, Canada

    International Nuclear Information System (INIS)

    In the Central Metasedimentary Belt of the Grenville Province, molybdenite occurs in many late tectonic uraniferous and thoriferous granitic pegmatites, pegmatite-related skarns (e.g., Halo, Hunt, Spain, and Zenith deposits) and skarnoid rocks (e.g., Liedke, Kirkham (Quebec), and Bain deposits), and fluorite-apatite-calcite vein-dykes (e.g., Kirkham, Quebec). This study presents robust Re-Os determinations from the various molybdenite-bearing U-Th-rare-metal pegmatitic dykes, skarns, and vein-dykes from throughout the southwestern Grenville Province, in order to unravel their chronologic history relative to the late geotectonic evolution of the southwestern Grenville Province and re-evaluate the genesis of these interrelated deposits. The Re-Os single crystal molybdenite age dating method is promising. In fact, the robustness of the single crystal Re-Os method has been shown to surpass the effects of prolonged granulite grade metamorphism, if the molybdenite crystals are isolated from other sulfide minerals and do not suffer from late fluid reaction

  18. Composition-selective fabrication of ordered intermetallic Au-Cu nanowires and their application to nano-size electrochemical glucose detection

    Science.gov (United States)

    Kim, Si-In; Eom, Gayoung; Kang, Mijeong; Kang, Taejoon; Lee, Hyoban; Hwang, Ahreum; Yang, Haesik; Kim, Bongsoo

    2015-06-01

    Bimetallic nanostructures can provide distinct and improved physicochemical properties by the coupling effect of the two metal components, making them promising materials for a variety of applications. Herein, we report composition-selective fabrication of ordered intermetallic Au-Cu nanowires (NWs) by two-step chemical vapor transport method and their application to nano-electrocatalytic glucose detection. Ordered intermetallic Au3Cu and AuCu3 NWs are topotaxially fabricated by supplying Cu-containing chemicals to pre-synthesized single-crystalline Au NW arrays. The composition of fabricated Au-Cu NWs can be selected by changing the concentration of Cu-containing species. Interestingly, Au3Cu NW electrodes show unique electrocatalytic activity for glucose oxidation, allowing us to detect glucose without interference from ascorbic acid. Such interference-free detection of glucose is attributed to the synergistic effect, induced by incorporation of Cu in Au. We anticipate that Au3Cu NWs could show possibility as efficient nano-size electrochemical glucose sensors and the present fabrication method can be employed to fabricate valuable ordered intermetallic nanostructures.

  19. Origin of epithermal Ag-Au-Cu-Pb-Zn mineralization in Guanajuato, Mexico

    Science.gov (United States)

    Mango, Helen; Arehart, Greg; Oreskes, Naomi; Zantop, Half

    2014-01-01

    The Guanajuato epithermal district is one of the largest silver producers in Mexico. Mineralization occurs along three main vein systems trending dominantly northwest-southeast: the central Veta Madre, the La Luz system to the northwest, and the Sierra system to the east. Mineralization consists dominantly of silver sulfides and sulfosalts, base metal sulfides (mostly chalcopyrite, galena, sphalerite, and pyrite), and electrum. There is a broad zonation of metal distribution, with up to 10 % Cu+Pb+Zn in the deeper mines along the northern and central portions of the Veta Madre. Ore occurs in banded veins and breccias and as stockworks, with gangue composed dominantly of quartz and calcite. Host rocks are Mesozoic sedimentary and intrusive igneous rocks and Tertiary volcanic rocks. Most fluid inclusion homogenization temperatures are between 200 and 300 °C, with salinities below 4 wt.% NaCl equivalent. Fluid temperature and salinity decreased with time, from 290 to 240 °C and from 2.5 to 1.1 wt.% NaCl equivalent. Relatively constant fluid inclusion liquid-to-vapor ratios and a trend of decreasing salinity with decreasing temperature and with increasing time suggest dilution of the hydrothermal solutions. However, evidence of boiling (such as quartz and calcite textures and the presence of adularia) is noted along the Veta Madre, particularly at higher elevations. Fluid inclusion and mineralogical evidence for boiling of metal-bearing solutions is found in gold-rich portions of the eastern Sierra system; this part of the system is interpreted as the least eroded part of the district. Oxygen, carbon, and sulfur isotope analysis of host rocks, ore, and gangue minerals and fluid inclusion contents indicate a hydrothermal fluid, with an initial magmatic component that mixed over time with infiltrating meteoric water and underwent exchange with host rocks. Mineral deposition was a result of decreasing activities of sulfur and oxygen, decreasing temperature, increasing p

  20. Studies of petrography, metasomatic alteration, and genesis of Kamtal iron-copper skarn, northeast of Kharvana, East-Azarbaijan

    Directory of Open Access Journals (Sweden)

    Rasool Ferdowsi

    2012-04-01

    Full Text Available Kamtal skarn is located 15 km northeast of Kharvana, East-Azarbaijan. A quartz-monzonitic stock of Oligocene age intruded the upper Cretaceous sedimentary sequence (claystone, limestone, marl, and siltstone developing noticeable metamorphic (marble, hornfels and metasomatic (skarn alteration zones along the contact. Kamtal skarn is of calcic type and consists of both endoskarn and exoskarn zones. Exoskarn includes two zones of garnet skarn and epidote skarn. Skarnification processes are divided mainly in two major stages (1 prograde and (2 retrograde. During prograde stage, the emplacement of intrusive body caused isochemical metamorphism of the wall rocks and developed marble and hornfels units in enclosing rocks. Crystallization of intrusive body led to evolvement of hydrothermal fluid phase which infiltrated into enclosing rocks. Reaction of these fluids with the early-formed metamorphosed wall rocks brought about extensive progressive metasomatic alteration characterized by the formation of anhydrous calc-silicate minerals such as garnets and pyroxenes at a temperature range of 420-550°C and ¦O2=10-22-10-25. Retrograde stage was accompanied by some physicochemical changes (decrease in temperature to <420°C and increase in ¦S2 which caused the alteration of pre-existing anhydrous calc-silicates to hydrous calc-silicates (epidote, and tremolite-actinolite, silicates (quartz, chlorites, and other clay minerals, oxides (magnetite and hematite, sulfides (pyrite, chalcopyrite, and tetrahedrite, and carbonate (calcite. Comparison of Kamtal skarn with some other ones of corresponding type from Iran and other countries shows that Kamtal skarn well resembles to Anjerd and Pahnavar skarns in East-Azarbaijan.

  1. A comparative study on geometries, stabilities, and electronic properties between bimetallic AgnX (X=Au, Cu; n=1-8) and pure silver clusters

    Institute of Scientific and Technical Information of China (English)

    Ding Li-Ping; Kuang Xiao-Yu; Shao Peng; Zhao Ya-Ru; Li Yah-Fang

    2012-01-01

    Using the meta-generalized gradient approximation (meta-GGA) exchange correlation TPSS functional,the geometric structures,the relative stabilities,and the electronic properties of bimetallic AgnX (X=Au,Cu; n=l-8) clusters are systematically investigated and compared with those of pure silver clusters.The optimized structures show that the transition point from preferentially planar to three-dimensional structure occurs at n =6 for the AgnAu clusters,and at n =5 for AgnCu clusters.For different-sized AgnX clusters,one X (X=Au or Cu) atom substituted Agn+1 structure is a dominant growth pattern.The calculated fragmentation energies,second-order differences in energies,and the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energy gaps show interesting odd-even oscillation behaviours,indicating that Ag2,4,6,8 and Ag1,3,5,7X (X=Au,Cu) clusters keep high stabilities in comparison with their neighbouring clusters.The natural population analysis reveals that the charges transfer from the Agn host to the impurity atom except for the Ag2Cu cluster.Moreover,vertical ionization potential (VIP),vertical electronic affinity (VEA),and chemical hardness (η) are discussed and compared in depth.The same odd-even oscillations are found for the VIP and ηof the AgnX (X=Au,Cu; n=1-8) clusters.

  2. Mineralogical composition of Oravita calcic skarns as a function of the high-temperature contact

    Science.gov (United States)

    Ghinet, Cristina; Marincea, Stefan; Dumitras, Delia

    2014-05-01

    Insignificant in terms of mineralization, the skarns of Oravita are scientifically interested because of their mineralogical associations. The higher crystallinity and good natural conditions (they are generally barren) are two characteristics of this rocks that can provide the ideally system to understand the behavior of the mineralogical components in certain conditions of temperature and pressure, but also for the hydrated carbonate phases whose forming understanding may be useful in the applied mineralogy. The occurrence of skarns from Oraviţa includes, as representative species, gehlenite, calcic garnet, monticellite, ellestadite-(OH), vesuvianite, that means in the geochemically terms CaO - SiO2 - H2O - Al2O3 system, usually described as C-S-H-A phases by the cement researches, difficult to study because of the small dimensions of the compounds crystals. The inner skarn zone is dominated by the presence of the gehlenite, an aluminum calcium silicate whose formation involves, as conditions, high temperature (~ 750oC) and low pressure (up to 1kbar). Typically, it is associated with monticellite, ellestadite-(OH), wollastonite 2M, diopside and calcic garnets. As it is expected, the intensity of the contact metamorphism decreases from the innermost to the outermost parts of the aureole, reflected in the chemical activity of the cations that participated at the chemical reactions. In this respect, the observed garnets are zoned, being characterized by a peripheral rich in Al, while the centers of the crystals are characterized by a high content of Fe and Ti. The replacement of gehlenite with vesuvianite along the metasomtatic front, a process that was observed at the optical microscope, indicates the existence of late stage metasomatic mineral phases. The presence of the vesuvianite, frequently including partially chloritized clintonite slides, and its main associated minerals as wollastonite 2M and calcium garnet with an andradite composition, points out the

  3. Thermodynamic properties of andradite and application to skarn with coexisting andradite and hedenbergite

    Science.gov (United States)

    Zhang, Zheru; Saxena, S. K.

    1991-04-01

    = - 20,441 - 1,342.8(1 - X_{Ad} )^2 - 1,312(1 - X_{Hd} )^2 . \\ For the assemblage andradite-hedenbergite-wollastonite-calcite: 1 410_2004_Article_BF00310711_TeX2GIFE10.gif begin{gathered} E = - 17.36;{text{ }}D = - 0.403; \\ A = 4log (X_{Ad} /X_{Hd} );{text{ C = 4;}} \\ B = - 11,720 - 1,342.8(1 - X_{Ad} )^2 - 1,312(1 - X_{Hd} )^2 \\ The oxygen fugacity of formation of those skarns where andradite and hedenbergite assemblage is typical can be calculated by using the above equations. The oxygen fugacity of formation of this kind of skarn ranges between carbon dioxide/graphite and hematite/magnetite buffers. It increases from the inside zones to the outside zones, and appears to decrease with the ore-types in the order Cu, Pb-Zn, Fe, Mo, W(Sn) ore deposits.

  4. Production of omega mesons in p+p, d+Au, Cu+Cu, and Au+Au collisions at sqrt(s_NN)=200 GeV

    CERN Document Server

    Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Al-Jamel, A; Alexander, J; Angerami, A; Aoki, K; Apadula, N; Aphecetche, L; Aramaki, Y; Armendariz, R; Aronson, S H; Asai, J; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Baldisseri, A; Barish, K N; Barnes, P D; Bassalleck, B; Basye, A T; Bathe, S; Batsouli, S; Baublis, V; Bauer, F; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bhom, J H; Bickley, A A; Bjorndal, M T; Blau, D S; Boissevain, J G; Bok, J S; Borel, H; Boyle, K; Brooks, M L; Brown, D S; Bucher, D; Buesching, H; Bumazhnov, V; Bunce, G; Burward-Hoy, J M; Butsyk, S; Camacho, C M; Campbell, S; Caringi, A; Chai, J -S; Chang, B S; Charvet, J -L; Chen, C -H; Chernichenko, S; Chi, C Y; Chiba, J; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Churyn, A; Chvala, O; Cianciolo, V; Citron, Z; Cleven, C R; Cobigo, Y; Cole, B A; Comets, M P; del Valle, Z Conesa; Connors, M; Constantin, P; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Dayananda, M K; Deaton, M B; Dehmelt, K; Delagrange, H; Denisov, A; d'Enterria, D; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Dion, A; Donadelli, M; Drachenberg, J L; Drapier, O; Drees, A; Drees, K A; Dubey, A K; Durham, J M; Durum, A; Dutta, D; Dzhordzhadze, V; D'Orazio, L; Edwards, S; Efremenko, Y V; Egdemir, J; Ellinghaus, F; Emam, W S; Engelmore, T; Enokizono, A; En'yo, H; Espagnon, B; Esumi, S; Eyser, K O; Fadem, B; Fields, D E; Finger, M; Finger, M; Fleuret, F; Fokin, S L; Forestier, B; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fung, S -Y; Fusayasu, T; Gadrat, S; Garishvili, I; Gastineau, F; Germain, M; Glenn, A; Gong, H; Gonin, M; Gosset, J; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Grim, G; Perdekamp, M Grosse; Gunji, T; Gustafsson, H -Å; Hachiya, T; Henni, A Hadj; Haegemann, C; Haggerty, J S; Hagiwara, M N; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Harada, H; Hartouni, E P; Haruna, K; Harvey, M; Haslum, E; Hasuko, K; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Heuser, J M; Hiejima, H; Hill, J C; Hobbs, R; Hohlmann, M; Holmes, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Hur, M G; Ichihara, T; Ichimiya, R; Ide, J; Iinuma, H; Ikeda, Y; Imai, K; Inaba, M; Inoue, Y; Isenhower, D; Isenhower, L; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Iwanaga, Y; Jacak, B V; Jia, J; Jiang, X; Jin, J; Jinnouchi, O; Johnson, B M; Jones, T; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kaneta, M; Kang, J H; Kanou, H; Kapustinsky, J; Karatsu, K; Kasai, M; Kawagishi, T; Kawall, D; Kawashima, M; Kazantsev, A V; Kelly, S; Kempel, T; Khanzadeev, A; Kijima, K M; Kikuchi, J; Kim, A; Kim, B I; Kim, D H; Kim, D J; Kim, E; Kim, E J; Kim, S H; Kim, Y -J; Kim, Y -S; Kim, Y J; Kinney, E; Kiriluk, K; Kiss, Á; Kistenev, E; Kiyomichi, A; Klay, J; Klein-Boesing, C; Kochenda, L; Kochetkov, V; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kozlov, A; Král, A; Kravitz, A; Kroon, P J; Kubart, J; Kunde, G J; Kurihara, N; Kurita, K; Kurosawa, M; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Bornec, Y Le; Leckey, S; Lee, D M; Lee, J; Lee, K; Lee, K B; Lee, K S; Lee, M K; Lee, T; Leitch, M J; Leite, M A L; Leitner, E; Lenzi, B; Li, X; Li, X H; Lichtenwalner, P; Liebing, P; Lim, H; Levy, L A Linden; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Mašek, L; Masui, H; Matathias, F; McCain, M C; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Mikeš, P; Miki, K; Miller, T E; Milov, A; Mioduszewski, S; Mishra, G C; Mishra, M; Mitchell, J T; Mitrovski, M; Mohanty, A K; Moon, H J; Morino, Y; Morreale, A; Morrison, D P; Moss, J M; Moukhanova, T V; Mukhopadhyay, D; Murakami, T; Murata, J; Nagamiya, S; Nagata, Y; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nam, S; Newby, J; Nguyen, M; Nihashi, M; Norman, B E; Nouicer, R; Nyanin, A S; Nystrand, J; Oakley, C; O'Brien, E; Oda, S X; Ogilvie, C A; Ohnishi, H; Ojha, I D; Oka, M; Okada, K; Omiwade, O O; Onuki, Y; Oskarsson, A; Otterlund, I; Ouchida, M; Ozawa, K; Pak, R; Pal, D; Palounek, A P T; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J -C; Pereira, H; Peresedov, V; Peressounko, D Yu; Petti, R; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Rembeczki, S; Reuter, M; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Romana, A; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ružička, P; Rykov, V L; Ryu, S S; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakai, S; Sakashita, K; Sakata, H; Samsonov, V; Sano, S; Sato, H D; Sato, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, A Yu; Semenov, V; Seto, R; Sharma, D; Shea, T K; Shein, I; Shevel, A; Shibata, T -A; Shigaki, K; Shimomura, M; Shohjoh, T; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Skutnik, S; Slunečka, M; Smith, W C; Soldatov, A; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Sparks, N A; Staley, F; Stankus, P W; Stenlund, E; Stepanov, M; Ster, A; Stoll, S P; Sugitate, T; Suire, C; Sukhanov, A; Sullivan, J P; Sziklai, J; Tabaru, T; Takagi, S; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, K H; Tanaka, Y; Taneja, S; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarján, P; Themann, H; Thomas, D; Thomas, T L; Togawa, M; Toia, A; Tojo, J; Tomášek, L; Torii, H; Towell, R S; Tram, V-N; Tserruya, I; Tsuchimoto, Y; Tuli, S K; Tydesjö, H; Tyurin, N; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wagner, M; Walker, D; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Willis, N; Winter, D; Wood, J P; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Yasin, Z; Ying, J; Yokkaichi, S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zaudtke, O; Zhang, C; Zhou, S; Zimányi, J; Zolin, L

    2011-01-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) has measured omega meson production via leptonic and hadronic decay channels in p+p, d+Au, Cu+Cu, and Au+Au collisions at sqrt(s_NN) = 200 GeV. The invariant transverse momentum spectra measured in different decay modes give consistent results. Measurements in the hadronic decay channel in Cu+Cu and Au+Au collisions show that omega production has a suppression pattern at high transverse momentum, similar to that of pi^0 and eta in central collisions, but no suppression is observed in peripheral collisions. The nuclear modification factors, R_AA, are consistent in Cu+Cu and Au+Au collisions at similar numbers of participant nucleons.

  5. Au/Cu2Te/CdTe/CdS/TCO/Glass Solar Cells with CdIn2O4 Obtained by Sol-Gel as TCO

    OpenAIRE

    Márquez Marín, J.; Torres Delgado, G.; M. A. Aguilar Frutis; Castanedo Pérez, R.; Zelaya Ángel, O.

    2014-01-01

    An Au/Cu2Te/CdTe/CdS/TCO/glass heterostructure based superstrate solar cells with 2.5 mm2 of area, where the CdTe layer was prepared by means of closed spaced sublimation (CSS) and the CdS by chemical bath, reached an efficiency η value of 12.1%. As transparent conductive oxide (TCO), a thin film of cadmium-indium oxide (CdIn2O4:CIO), obtained by sol-gel technique, was used. A systematic optimization of the thermal activation of the CdTe/CdS/CIO central part of the device with a CdCl2 vapor a...

  6. Au plasmonics in a WS{sub 2}-Au-CuInS{sub 2} photocatalyst for significantly enhanced hydrogen generation

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Zhongzhou [CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190 (China); School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Wang, Zhenxing, E-mail: wangzx@nanoctr.cn, E-mail: hej@nanoctr.cn; Shifa, Tofik Ahmed; Wang, Fengmei; Zhan, Xueying; Xu, Kai; He, Jun, E-mail: wangzx@nanoctr.cn, E-mail: hej@nanoctr.cn [CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190 (China); Liu, Quanlin [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-11-30

    Promoting the activities of photocatalysts is still the critical challenge in H{sub 2} generation area. Here, a Au plasmon enhanced photocatalyst of WS{sub 2}-Au-CuInS{sub 2} is developed by inserting Au nanoparticles between WS{sub 2} nanotubes and CuInS{sub 2} (CIS) nanoparticles. Due to the localized surface plasmonic resonance properties from Au nanoparticles, WS{sub 2}-Au-CIS shows the best performance as compared to Au-CIS, CIS, WS{sub 2}-CIS, CIS-Au, WS{sub 2}-Au, and WS{sub 2}-CIS-Au. The surface plasmonic resonance effects dramatically intensify the absorption of visible light and help to inject hot electrons into the semiconductors. Our findings open up an efficient method to optimize the type-II structures for photocatalytic water splitting.

  7. Au/Cu2Te/CdTe/CdS/TCO/Glass Solar Cells with CdIn2O4 Obtained by Sol-Gel as TCO

    Directory of Open Access Journals (Sweden)

    J. Márquez Marín

    2014-01-01

    Full Text Available An Au/Cu2Te/CdTe/CdS/TCO/glass heterostructure based superstrate solar cells with 2.5 mm2 of area, where the CdTe layer was prepared by means of closed spaced sublimation (CSS and the CdS by chemical bath, reached an efficiency η value of 12.1%. As transparent conductive oxide (TCO, a thin film of cadmium-indium oxide (CdIn2O4:CIO, obtained by sol-gel technique, was used. A systematic optimization of the thermal activation of the CdTe/CdS/CIO central part of the device with a CdCl2 vapor ambient made the conversion efficiency of the Au/Cu2Te/CdTe/CdS/CIO/glass heterostructure reaches 9.94% for the CdTe layer with thickness of 1.8 μm. This efficiency was reached only through an open circuit voltage VOC optimization. A maximum η of 12.1% was reached with the established procedure of optimization and when the CdTe layer thickness was increased to 3.1 ± 0.05 μm. The substitution of CIO by commercial ITO provoked in the cell a decrease of η from 12.1% to 7.2%, both devices prepared under the same conditions. Starting from these results, we can say that CIO was a better TCO than commercial ITO in our solar cell, with the advantage that CIO was obtained by sol-gel, which is a simple and economical technique.

  8. Physicochemical conditions of skarn formation in contact of the Alvand batholith with the meta-calcareous rocks, Hamedan, western Iran

    Directory of Open Access Journals (Sweden)

    Adel Saki

    2012-04-01

    Full Text Available The Cheshin meta-calcareous rocks (Permo Triassic in southeast Hamedan outcrop in association with a variety of pelitic schists and hornfels rocks. The intrusion of the Alvand Batholith (Jurassic age into pelitic and calcareous host rocks has produced metamorphic rocks in the Hamedan area (Cheshin village. On the basis of the dominance of calcite/dolomite, silicate and ore minerals, the calcareous rocks can be divided into two groups: a marbles and calc-silicates; b skarn rocks. The ore bodies occur in a contact zone between sillimanite-hornfels and calc-silicate rocks and formed the skarn rocks. Based on mineralogy, skarn rocks in the studied area consist mainly of diopside, garnet, tremolite, vesuvianite, epidote and ore minerals (magnetite and hematite. The skarnification processes occurred at two stages: (1 prograde metamorphism; and (2 retrograde metamorphism. The first stage involved prograde metasomatism and anhydrous minerals such as garnet and pyroxene formed. Second stage of retrograde skarn development is also recognized. In addition to Fe, Si and Mg, substantial amounts of Fe, along with volatile components were added to the skarn system. Consequently, considerable amounts of hydrous minerals, oxides and carbonates replaced the anhydrous minerals in the host rocks and hydrous minerals such as epidote+chlorite+amphibole formed. Using multiple equilibria by THERMOCALC® program, temperature (~630 ºC, pressure (~4 kbar, and fluid composition (XCO2 as low as 0.17 have been calculated for the formation of the calc-silicate rocks. Skarn mineralogy shows good agreement with these calculations.

  9. Archean high-Mg monzodiorite-syenite, epidote skarn, and biotite-sericite gold lodes in the Granny Smith-Wallaby district, Australia: U-Pb and Re-Os chronometry of two intrusion-related hydrothermal systems

    Science.gov (United States)

    Mueller, Andreas G.; Hall, Gregory C.; Nemchin, Alexander A.; Stein, Holly J.; Creaser, Robert A.; Mason, Douglas R.

    2008-03-01

    The Granny Smith (37 t Au production) and Wallaby deposits (38 t out of a 180 t Au resource) are located northeast of Kalgoorlie, in 2.7 Ga greenstones of the Eastern Goldfields Province, the youngest orogenic belt of the Yilgarn craton, Western Australia. At Granny Smith, a zoned monzodiorite-granodiorite stock, dated by a concordant titanite-zircon U-Pb age of 2,665 ± 3 Ma, cuts across east-dipping thrust faults. The stock is fractured but not displaced and sets a minimum age for large-scale (1 km) thrust faulting (D2), regional folding (D1), and dynamothermal metamorphism in the mining district. The local gold-pyrite mineralization, controlled by fractured fault zones, is younger than 2,665 ± 3 Ma. In augite-hornblende monzodiorite, alteration progressed from a hematite-stained alkali feldspar-quartz-calcite assemblage and quartz-molybdenite-pyrite veins to a late reduced sericite-dolomite-albite assemblage. Gold-related monazite and xenotime define a U-Pb age of 2,660 ± 5 Ma, and molybdenite from veins a Re-Os isochron age of 2,661 ± 6 Ma, indicating that mineralization took place shortly after the emplacement of the main stock, perhaps coincident with the intrusion of late alkali granite dikes. At Wallaby, a NE-trending swarm of porphyry dikes comprising augite monzonite, monzodiorite, and minor kersantite intrudes folded and thrust-faulted molasse. The conglomerate and the dikes are overprinted by barren (1,600-m-long replacement pipe, which is intruded by a younger ring dike of syenite porphyry pervasively altered to muscovite + calcite + pyrite. Skarn and syenite are cut by pink biotite-calcite veins, containing magnetite + pyrite and subeconomic gold-silver mineralization (Au/Ag = 0.2). The veins are associated with red biotite-sericite-calcite-albite alteration in adjacent monzonite dikes. Structural relations and the concordant titanite U-Pb age of the skarn constrain intrusion-related mineralization to 2,662 ± 3 Ma. The main-stage gold-pyrite ore

  10. Mineralogical Description of the Skarn from Mraconia Valley, Almaj Mountains, Romania

    Science.gov (United States)

    Anason, Maria Angela; Stefan, Marincea; Delia Georgeta, Dumitras

    2014-05-01

    The purpose of this paper is to update knowledge of the investegated area. The research are overlaps of the hidrographic basin of the Mraconia Valley, at north is bounded by the alignment Poiana Mraconia and Lugojistea; at east by the Satului Valley; souther limit is constitutes by the Ponicova Valley and the western limit is Cracul Radului-Cracul Urzicea. The skarn was described for the first time in the 1934 by the A. Streckeisan with the name Catramat Series; this series was a kata-mezonal character, which is the debris of an old canvas with Upper Carbonifer age. The crystalline schist of the Poiana Mraconia Series, are studied by Al. Codarcea, I. Bercia, E. Bercia (1934) and suffered a progressive metamorphism in the amphibolites with alamandine facies and the disten-alamandine-muscovite subfacies, together revealed the metapelithe paragenesis including disten, green hornblende, andezine and alamandine.The primar metamorphism were followed to the regressive metamorphism by the Assyntic orogene and Varisc cycles (I. Bercia, E. Bercia, 1975). Petrografically exceed the amphibolites paragnaice and the micacee paragnaice, with biotite and garnet, associated with the quartz-feldspar gneiss and feldspar quartzite, affected by the arthritic migmatization. Fine grain, sharp sistuozity, the muscovite are frequent and the pegmatite absence leading to the Poiana Mraconia crystalline differentiation by the Ielova crystalline, bud both are included in the Almaj complex. Mineralogical and petrographic study of the Mraconia skarns serves in predicting the relations between the magmatite form the upper basin of the valley (with the mineralization of the W and Mo), and the adjacent formations. This paper wants to emphasize the next petrographic types following: 1. the micacee paragnais are characterized by the existing of the quartz, plagioclase, microcline, muscovite, biotite, chlorite and epidote; 2. The micacee paragnais with garnet are definite by the paragenisis: quartz

  11. Modelo genéticode los skarns de Fe de Vegas Peladas, Mendoza

    OpenAIRE

    2009-01-01

    Datos de inclusiones fluidas(IF) indican que el skarn de Fe relacionado al plutón diorítico de VegasPeladas se originó a 3,5 km de profundidad, bajo presiones litostáticas de 950bares y a expensas de fluidos muy salinos (hasta 70% NaCl eq.) de altatemperatura (670-400°C). Es muy factible que estos fluidos ricos en NaCl ± KCl± FeCln ± hematita junto con vapor se hayan formado por la inmiscibilidad defluidos magmáticos de salinidad baja (6-8% NaCl eq.). Los datos isotópicos delagua en equilibri...

  12. Nuclear modification factors of phi mesons in d+Au, Cu+Cu and Au+Au collisions at sqrt(S_NN)=200 GeV

    CERN Document Server

    Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Al-Jamel, A; Angerami, A; Aoki, K; Aphecetche, L; Aramaki, Y; Armendariz, R; Aronson, S H; Asai, J; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Baldisseri, A; Barish, K N; Barnes, P D; Bassalleck, B; Basye, A T; Bathe, S; Batsouli, S; Baublis, V; Bauer, F; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bhom, J H; Bickley, A A; Bjorndal, M T; Blau, D S; Boissevain, J G; Bok, J S; Borel, H; Borggren, N; Boyle, K; Brooks, M L; Brown, D S; Bucher, D; Buesching, H; Bumazhnov, V; Bunce, G; Burward-Hoy, J M; Butsyk, S; Campbell, S; Caringi, A; Cassano, N; Chai, J -S; Chang, B S; Charvet, J -L; Chen, C -H; Chernichenko, S; Chiba, J; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Churyn, A; Chvala, O; Cianciolo, V; Citron, Z; Cleven, C R; Cobigo, Y; Cole, B A; Comets, M P; del Valle, Z Conesa; Connors, M; Constantin, P; Csanad, M; Csorgo, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Dayananda, M K; Deaton, M B; Dehmelt, K; Delagrange, H; Denisov, A; d'Enterria, D; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Dion, A; Donadelli, M; Orazio, L D; Drachenberg, J L; Drapier, O; Drees, A; Drees, K A; Dubey, A K; Durham, J M; Durum, A; Dutta, D; Dzhordzhadze, V; Edwards, S; Efremenko, Y V; Egdemir, J; Ellinghaus, F; Emam, W S; Engelmore, T; Enokizono, A; En'yo, H; Espagnon, B; Esumi, S; Eyser, K O; Fadem, B; Fields, D E; Finger, M; Finger, M; Fleuret, F; Fokin, S L; Forestier, B; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fung, S -Y; Fusayasu, T; Gadrat, S; Garishvili, I; Gastineau, F; Germain, M; Glenn, A; Gong, H; Gonin, M; Gosset, J; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Grim, G; Perdekamp, M Grosse; Gunji, T; Gustafsson, H -A; Hachiya, T; Henni, A Hadj; Haegemann, C; Haggerty, J S; Hagiwara, M N; Hahn, K I; Hamagaki, H; Hamblen, J; Hanks, J; Han, R; Harada, H; Hartouni, E P; Haruna, K; Harvey, M; Haslum, E; Hasuko, K; Hayano, R; Heffner, M; Hemmick, T K; Hester, T; Heuser, J M; He, X; Hiejima, H; Hill, J C; Hobbs, R; Hohlmann, M; Holmes, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Hur, M G; Ichihara, T; Ichimiya, R; Iinuma, H; Ikeda, Y; Imai, K; Inaba, M; Inoue, Y; Isenhower, D; Isenhower, L; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Iwanaga, Y; Jacak, B V; Jia, J; Jiang, X; Jin, J; Jinnouchi, O; Johnson, B M; Jones, T; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kaneta, M; Kang, J H; Kanou, H; Kapustinsky, J; Karatsu, K; Kasai, M; Kawagishi, T; Kawall, D; Kawashima, M; Kazantsev, A V; Kelly, S; Kempel, T; Khanzadeev, A; Kijima, K M; Kikuchi, J; Kim, A; Kim, B I; Kim, D H; Kim, D J; Kim, E J; Kim, E; Kim, Y -J; Kim, Y -S; Kinney, E; Kiss, A; Kistenev, E; Kiyomichi, A; Klay, J; Klein-Boesing, C; Kochenda, L; Kochetkov, V; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kotov, D; Kozlov, A; Kral, A; Kravitz, A; Kroon, P J; Kubart, J; Kunde, G J; Kurihara, N; Kurita, K; Kurosawa, M; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Le Bornec, Y; Leckey, S; Lee, D M; Lee, J; Lee, K B; Lee, K S; Lee, M K; Lee, T; Leitch, M J; Leite, M A L; Lenzi, B; Lichtenwalner, P; Liebing, P; Lim, H; Levy, L A Linden; Liska, T; Litvinenko, A; Liu, H; Liu, M X; Li, X; Li, X H; Love, B; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masek, L; Masui, H; Matathias, F; McCain, M C; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Mikes, P; Miki, K; Miller, T E; Milov, A; Mioduszewski, S; Mishra, G C; Mishra, M; Mitchell, J T; Mitrovski, M; Mohanty, A K; Moon, H J; Morino, Y; Morreale, A; Morrison, D P; Moss, J M; Moukhanova, T V; Mukhopadhyay, D; Murakami, T; Murata, J; Nagamiya, S; Nagata, Y; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nam, S; Newby, J; Nguyen, M; Nihashi, M; Norman, B E; Nouicer, R; Nyanin, A S; Nystrand, J; Oakley, C; O'Brien, E; Oda, S X; Ogilvie, C A; Ohnishi, H; Ojha, I D; Okada, K; Oka, M; Omiwade, O O; Onuki, Y; Oskarsson, A; Otterlund, I; Ouchida, M; Ozawa, K; Pak, R; Pal, D; Palounek, A P T; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J -C; Pereira, H; Peresedov, V; Peressounko, D Yu; Petti, R; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Rembeczki, S; Reuter, M; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Romana, A; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ruzicka, P; Rykov, V L; Ryu, S S; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakai, S; Sakashita, K; Sakata, H; Samsonov, V; Sano, S; Sato, H D; Sato, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, V; Seto, R; Sharma, D; Shea, T K; Shein, I; Shevel, A; Shibata, T -A; Shigaki, K; Shimomura, M; Shohjoh, T; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Skutnik, S; Slunecka, M; Smith, W C; Soldatov, A; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Staley, F; Stankus, P W; Stenlund, E; Stepanov, M; Ster, A; Stoll, S P; Sugitate, T; Suire, C; Sukhanov, A; Sullivan, J P; Sziklai, J; Tabaru, T; Takagi, S; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, K H; Tanaka, Y; Taneja, S; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarjan, P; Themann, H; Thomas, D; Thomas, T L; Togawa, M; Toia, A; Tojo, J; Tomasek, L; Torii, H; Towell, R S; Tram, V-N; Tserruya, I; Tsuchimoto, Y; Tuli, S K; Tydesjo, H; Tyurin, N; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vertesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wagner, M; Walker, D; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wessels, J; White, S N; Willis, N; Winter, D; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Yasin, Z; Ying, J; Yokkaichi, S; Young, G R; Younus, I; You, Z; Yushmanov, I E; Zajc, W A; Zaudtke, O; Zhang, C; Zhou, S; Zimanyi, J; Zolin, L

    2010-01-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) has performed systematic measurements of phi meson production in the K+K- decay channel at midrapidity in p+p, d+Au, Cu+Cu and Au+Au collisions at sqrt(S_NN)=200 GeV. Results are presented on the phi invariant yield and the nuclear modification factor R_AA for Au+Au and Cu+Cu, and R_dA for d+Au collisions, studied as a function of transverse momentum (1

  13. Factor analysis of d(NE)/dE Auger electron spectra of AuCu alloys: surface composition during Ar + ion bombardment and oxidation

    International Nuclear Information System (INIS)

    Factor analysis is applied to d(NE)/dE Auger electron spectra of a series of AuCu alloys (25% Au, 50% Au and 75% Au), including in the analysis the spectra of clean Au and Cu surfaces. Surface quantitation is obtained from the low-energy Au NOO and Cu LMM spectra of the alloys. The overlap of these spectra is resolved with factor analysis. An accuracy of the derived, relative surface concentrations of 1:100 is possible with this method, with a similar sensitivity to changes in surface composition. During Ar+ ion bombardment the surfaces of 25% and 50% Au alloys show no difference from the bulk concentrations, within ±1:100, from 1 to 3 keV Ar+ ion energy. For the 75% Au alloy, a slight Au enrichment is produced, when the energy increases from 1 to 3 keV. However, at 500 eV Ar+ ion energy, the surfaces become strongly enriched in Au, probably due to threshold effects for Au. Thus, no evidence for such strongly varying processes are found in molecular dynamics simulations of the mass effect in the sputtering process from a 50%:50% alloy. Factor analysis is also used to detect the presence of chemically affected spectral features during oxygen exposure at room temperature of the alloys and of pure Cu. Oxidation of the copper component is observed, producing at saturation a cuprous oxide with a total copper enrichment of the surface. (author)

  14. Hydrogen Balmer {alpha} line behavior in Laser-Induced Breakdown Spectroscopy depth scans of Au, Cu, Mn, Pb targets in air

    Energy Technology Data Exchange (ETDEWEB)

    Senesi, G.S., E-mail: giorgio.senesi@ba.imip.cnr.i [Institute of Inorganic Methodologies and Plasmas, Via Amendola 122/D, 70126 Bari (Italy); Benedetti, P.A.; Cristoforetti, G.; Legnaioli, S.; Palleschi, V. [Applied Laser Spectroscopy Laboratory, Institute of Chemical-Physical Processes, Research Area of National Research Council, Via G. Moruzzi 1, 56124 Pisa (Italy)

    2010-07-15

    The behavior of hydrogen spectral emission of the plasmas obtained by Laser-Induced Breakdown Spectroscopy (LIBS) measurement of four metal targets (Au, Cu, Mn, Pb) in air was investigated. The plasma was produced by a pulsed Nd:YAG laser emitting in the fundamental wavelength. A systematic study of the spatial-integrated plasma emission obtained by an in-depth scanning of the target was performed for each metal, both in single pulse and collinear double-pulse configurations. Further, a spatial-resolved analysis of the emission of plasma produced on the Al target by a single laser pulse was performed, in order to describe the spatial distribution of emitters deriving from the target and air elements. The line intensities of the main plasma components (target metal, nitrogen, oxygen and hydrogen) were measured in both experimental conditions. Results show that the hydrogen line intensity varies greatly as a function of the metal considered, and exhibits a marked decrease after the first laser shots. However, differently from emission lines due to surface impurities, the hydrogen line intensity reaches a constant level deep inside the target. The spatial-resolved measurements indicate that hydrogen atoms in the plasma mainly derive from the target surface and, only at a minor extent, from the dissociation of molecular hydrogen present in the surrounding air. These findings show that the calculation of plasma electron number density through the measurement of the Stark broadening of hydrogen Balmer {alpha} line is possible also in depth scanning measurements.

  15. Hydrogen Balmer α line behavior in Laser-Induced Breakdown Spectroscopy depth scans of Au, Cu, Mn, Pb targets in air

    Science.gov (United States)

    Senesi, G. S.; Benedetti, P. A.; Cristoforetti, G.; Legnaioli, S.; Palleschi, V.

    2010-07-01

    The behavior of hydrogen spectral emission of the plasmas obtained by Laser-Induced Breakdown Spectroscopy (LIBS) measurement of four metal targets (Au, Cu, Mn, Pb) in air was investigated. The plasma was produced by a pulsed Nd:YAG laser emitting in the fundamental wavelength. A systematic study of the spatial-integrated plasma emission obtained by an in-depth scanning of the target was performed for each metal, both in single pulse and collinear double-pulse configurations. Further, a spatial-resolved analysis of the emission of plasma produced on the Al target by a single laser pulse was performed, in order to describe the spatial distribution of emitters deriving from the target and air elements. The line intensities of the main plasma components (target metal, nitrogen, oxygen and hydrogen) were measured in both experimental conditions. Results show that the hydrogen line intensity varies greatly as a function of the metal considered, and exhibits a marked decrease after the first laser shots. However, differently from emission lines due to surface impurities, the hydrogen line intensity reaches a constant level deep inside the target. The spatial-resolved measurements indicate that hydrogen atoms in the plasma mainly derive from the target surface and, only at a minor extent, from the dissociation of molecular hydrogen present in the surrounding air. These findings show that the calculation of plasma electron number density through the measurement of the Stark broadening of hydrogen Balmer α line is possible also in depth scanning measurements.

  16. Geochemistry blocks to predict significant mineral deposits in the Antioquia Department Republic of Colombia Au, Cu, Mn, Mo, Ni, Pb, Zn elements

    OpenAIRE

    SÁNCHEZ ARREDONDO, LUIS HERNÁN; Molina Escobar, Jorge Martín

    2007-01-01

    The geochemical sampling allows determining the geochemical provinces, defined as an “earth crust portion or segment that has a significant chemical composition different of the average (Rose et al., 1979)”. These researches involve the analysis of a great number of elements that are not commonly considered in traditional exploration studies making recognition of large areas, discovering potential areas for the mining prospection. From the environmental point of view, it is possible to detect...

  17. Caracterización geológica del skarn "El Abuelo" Alto Río Senguerr, Chubut

    Directory of Open Access Journals (Sweden)

    M.E. Lanfranchini

    2004-12-01

    Full Text Available El skarn "El Abuelo" está situado en el extremo sudoccidental de la Provincia del Chubut, República Argentina. Se desarrolla en un ambiente tectónico de arco magmático, en corteza continental. Está emplazado en sedimentitas silicoclásticas con intercalaciones carbonáticas y se vincula a cuerpos intrusivos riodacíticos, conjunto atribuido al Cretácico inferior. En esta manifestación se reconocieron anomalías en elementos metalíferos (Fe, Cu, Pb, Zn, Ag que le confieren interés como guía para la exploración de recursos minerales en esta región. La presente contribución tiene por finalidad tipificar al skarn a través de una caracterización geológica y mineralógica. La asociación paragenética de minerales reconocidos permitió identificar dos episodios: uno metasomático y otro hidrotermal, ambos desarrollados en las sedimentitas (exoskarn. El primero fue originado por fluidos de derivación magmática, que provocaron la formación de minerales calcosilicáticos. Posteriormente la incorporación de agua en el sistema facilitó el desarrollo de minerales hidratados, retrogradando parcialmente al skarn, proceso que fue seguido por la depositación de hematita, magnetita y sulfuros, acompañados de sílice. La asociación de minerales calcosilicáticos, junto a la variación en la composición química de piroxenos y granates y la mineralización identificada, permiten tipificar al skarn "El Abuelo" como cálcico, con hierro como metal dominante.

  18. On the mechanisms of cation injection in conducting bridge memories: The case of HfO2 in contact with noble metal anodes (Au, Cu, Ag)

    Science.gov (United States)

    Saadi, M.; Gonon, P.; Vallée, C.; Mannequin, C.; Grampeix, H.; Jalaguier, E.; Jomni, F.; Bsiesy, A.

    2016-03-01

    Resistance switching is studied in HfO2 as a function of the anode metal (Au, Cu, and Ag) in view of its application to resistive memories (resistive random access memories, RRAM). Current-voltage (I-V) and current-time (I-t) characteristics are presented. For Au anodes, resistance transition is controlled by oxygen vacancies (oxygen-based resistive random access memory, OxRRAM). For Ag anodes, resistance switching is governed by cation injection (Conducting Bridge random access memory, CBRAM). Cu anodes lead to an intermediate case. I-t experiments are shown to be a valuable tool to distinguish between OxRRAM and CBRAM behaviors. A model is proposed to explain the high-to-low resistance transition in CBRAMs. The model is based on the theory of low-temperature oxidation of metals (Cabrera-Mott theory). Upon electron injection, oxygen vacancies and oxygen ions are generated in the oxide. Oxygen ions are drifted to the anode, and an interfacial oxide is formed at the HfO2/anode interface. If oxygen ion mobility is low in the interfacial oxide, a negative space charge builds-up at the HfO2/oxide interface. This negative space charge is the source of a strong electric field across the interfacial oxide thickness, which pulls out cations from the anode (CBRAM case). Inversely, if oxygen ions migration through the interfacial oxide is important (or if the anode does not oxidize such as Au), bulk oxygen vacancies govern resistance transition (OxRRAM case).

  19. Saltwater ecotoxicology of Ag, Au, CuO, TiO2, ZnO and C60 engineered nanoparticles: An overview.

    Science.gov (United States)

    Minetto, D; Volpi Ghirardini, A; Libralato, G

    2016-01-01

    This review paper examined 529 papers reporting experimental nanoecotoxicological original data. Only 126 papers referred to saltwater environments (water column and sediment) including a huge variety of species (n=51), their relative endpoints and engineered nanoparticles (ENPs) (n=38). We tried to provide a synthetic overview of the ecotoxicological effects of ENPs from existing data, refining papers on the basis of cross-cutting selection criteria and supporting a "mind the gap" approach stressing on missing data for hazard and risk assessment. After a codified selection procedure, attention was paid to Ag, Au, CuO, TiO2, ZnO and C60 ENPs, evidencing and comparing the observed nanoecotoxicity range of effect. Several criticisms were evidenced: i) some model organisms are overexploited like microalgae and molluscs compared to annelids, echinoderms and fish; ii) underexploited model organisms: mainly bacteria and fish; iii) exposure scenario variability: high species-specific and ENP scenarios including organism life stage and way of administration/spiking of toxicants; iv) scarce comparability between results due to exposure scenario variability; v) micro- and mesocosms substantially unexplored; vi) mixture effects: few examples are available only for ENPs and traditional pollutants; mixtures of ENPs have not been investigated yet; vii) effects of ions and ENPs: nAg, nCuO and nZnO toxicity aetiology is still a matter of discussion; viii) size and morphology effects of ENPs: scarcely investigated, justified and understood. Toxicity results evidenced that: nAu>nZnO>nAg>nCuO>nTiO2>C60. PMID:27107224

  20. Modelo genéticode los skarns de Fe de Vegas Peladas, Mendoza

    Directory of Open Access Journals (Sweden)

    María Josefina Pons

    2009-06-01

    Full Text Available Datos de inclusiones fluidas(IF indican que el skarn de Fe relacionado al plutón diorítico de VegasPeladas se originó a 3,5 km de profundidad, bajo presiones litostáticas de 950bares y a expensas de fluidos muy salinos (hasta 70% NaCl eq. de altatemperatura (670-400°C. Es muy factible que estos fluidos ricos en NaCl ± KCl± FeCln ± hematita junto con vapor se hayan formado por la inmiscibilidad defluidos magmáticos de salinidad baja (6-8% NaCl eq.. Los datos isotópicos delagua en equilibrio con el granate (δ18O 7,2-8,5‰ y conla magnetita (4,8-7,9‰ confirman el origen magmático de estos fluidos.Debido a la interacción con la caja y a la formación del exoskarn degranate-clinopiroxeno, los fluidos redujeron isobáricamente sus temperaturas(hasta ~250°C. La continua exsolución de volátiles del magma y el sellado delos conductos de circulación de los fluidos por la precipitación de lossilicatos (magnetita del exoskarn y de la alteración del borde delplutón, generaron sobrepresiones, el fracturamiento de las rocas y laebullición del fluido. Bajo condiciones hidrostáticas, el aumento de lapermeabilidad permitió el ingreso de las aguas externas al sistema que semezclaron con los fluidos magmáticos provocando el reemplazo de los silicatospor minerales hidratados, cuarzo (con valores δ18O del fluidode -0,55 a 4,5‰ y la precipitación masiva de óxidos de hierro. Losregistros en inclusiones fluidas señalan temperaturas de 420° a 320°C,presiones hidrostáticas de 325 a 125 bares y fluidos menos salinos (41,6-23%NaCl eq. para este estadio. La disminución de la temperatura y de la salinidadfueron los factores principales que favorecieron la precipitación de la mena deFe. Las venillas tardías que cortan a las alteraciones anteriores se formaron alas temperaturas (165-315°C y salinidades (8,41 y 13,51% NaCl eq. más bajasdel sistema. Los valores δ18O del agua en equilibrio con elepidoto (-4,66 a 0,19‰ y con la calcita

  1. First-principles theory of short-range order in size-mismatched metal alloys: Cu-Au, Cu-Ag, and Ni-Au

    International Nuclear Information System (INIS)

    We describe a first-principles technique for calculating the short-range order (SRO) in disordered alloys, even in the presence of large anharmonic atomic relaxations. The technique is applied to several alloys possessing large size mismatch: Cu-Au, Cu-Ag, Ni-Au, and Cu-Pd. We find the following: (i) The calculated SRO in Cu-Au alloys peaks at (or near) the left-angle 100 right-angle point for all compositions studied, in agreement with diffuse scattering measurements. (ii) A fourfold splitting of the X-point SRO exists in both Cu0.75Au0.25 and Cu0.70Pd0.30, although qualitative differences in the calculated energetics for these two alloys demonstrate that the splitting in Cu0.70Pd0.30 may be accounted for by T=0 K energetics while T≠0 K configurational entropy is necessary to account for the splitting in Cu0.75Au0.25. Cu0.75Au0.25 shows a significant temperature dependence of the splitting, in agreement with recent in situ measurements, while the splitting in Cu0.70Pd0.30 is predicted to have a much smaller temperature dependence. (iii) Although no measurements exist, the SRO of Cu-Ag alloys is predicted to be of clustering type with peaks at the left-angle 000 right-angle point. Streaking of the SRO peaks in the left-angle 100 right-angle and left-angle 1 (1) /(2) 0 right-angle directions for Ag- and Cu-rich compositions, respectively, is correlated with the elastically soft directions for these compositions. (iv) Even though Ni-Au phase separates at low temperatures, the calculated SRO pattern in Ni0.4Au0.6, like the measured data, shows a peak along the left-angle ζ00 right-angle direction, away from the typical clustering-type left-angle 000 right-angle point. (v) The explicit effect of atomic relaxation on SRO is investigated and it is found that atomic relaxation can produce significant qualitative changes in the SRO pattern, changing the pattern from ordering to clustering type, as in the case of Cu-Ag. copyright 1998 The American Physical Society

  2. Multistage Carbonatization and Mineral Geochemistry of a Skarn—type Copper Deposit at Tongshan ,Guichi

    Institute of Scientific and Technical Information of China (English)

    邱瑞龙

    1991-01-01

    The Tongshan copper deposit at Guichi can be considered as a skarn-type copper deposit.Mul-ti-stage carbonatization was well developed in the skarn zone and copper-bearing orebodies,Mineralogy,mineral chemistry and stable isotope data allow it to be divided into five stages:(1)carbonatization of single calcite crystals in the skarn stage;(2)calcite carbonatization in the oxide stage;(3)carbonatization in the early sulfide stage;(4)carbonatization in the late sulfide stage;and (5)carbonatization in the post-sulfide stage.Carbonatization in the early sulide stage is ,among other things,closely related to copper mineralization and is one of the alteration indicators of copper mineralization of this type.C.O,Rb and Sr isotopic studies indicate that the cakites of skarn and oxide stages were formed from hydrothermal solutions predominated by magmatic water,and those of sulfide stage were formed from hydrothermal solutions mainly involving heated meteoric warer.The former was formed in the environment where ?o2(?o2>10-33and 10-33>?o2>10-36)(pH=7-8)is high as compared with the latter(10-35>?o2>10-38;pH=5.7).

  3. NEAR-ABSOLUTE EQUATIONS OF STATE OF DIAMOND, Ag, Al, Au, Cu, Mo, Nb, Pt, Ta, AND W FOR QUASI-HYDROSTATIC CONDITIONS

    Directory of Open Access Journals (Sweden)

    Peter I. Dorogokupets

    2015-09-01

    Full Text Available Using the modified formalism of [Dorogokupets, Oganov, 2005, 2007], equations of state are developed for diamond, Ag, Al, Au, Cu, Mo, Nb, Pt, Ta, and W by simultaneous optimization of shock-wave data, ultrasonic, X-ray, dilatometric and thermochemical measurements in the temperature range from ~100 K to the melting temperature and pressures up to several Mbar, depending on the substance. The room-temperature isotherm is given in two forms: (1 the equation from [Holzapfel, 2001, 2010] which is the interpolation between the low pressure (x≥1 and the pressure at infinite compression (x=0; it corresponds to the Thomas-Fermi model, and (2 the equation from [Vinet et al., 1987]. The volume dependence of the Grüneisen parameter is calculated according to equations from [Zharkov, Kalinin, 1971; Burakovsky, Preston, 2004] with adjustable parameters, t and δ. The room-temperature isotherm and the pressure on the Hugoniot adiabat are determined by three parameters, K', t and δ, and K0 is calculated from ultrasonic measurements. In our study, reasonably accurate descriptions of all of the basic thermodynamic functions of metals are derived from a simple equation of state with a minimal set of adjustable parameters.The pressure calculated from room-temperature isotherms can be correlated with a shift of the ruby R1 line. Simultaneous measurements of the shift and unit cell parameters of metals are conducted in mediums containing helium [Dewaele et al., 2004b; 2008; Takemura, Dewaele, 2008; Takemura, Singh, 2006], hydrogen [Chijioke et al., 2005] and argon [Tang et al., 2010]. According to [Takemura, 2001], the helium medium in diamond anvil cells provides for quasi-hydrostatic conditions; therefore, the ruby pressure scale, that is calibrated for the ten substances, can be considered close to equilibrium or almost absolute. The ruby pressure scale is given as P(GPa=1870⋅Δλ/λ0⋅(1+6⋅Δλ/λ0. The room-temperature isotherms corrected with regard

  4. The occurring forms of thorium and characteristics of thorium mineral of skarn-type thorium deposit in Tranomaro, southern Madagascar

    International Nuclear Information System (INIS)

    In Tranomaro, thorium mineralization mainly occurs in Tranomaro pyroxenite which formed under skarnization and it mainly consists of diopside, scaponite and carbonate. Thorium exists in the form of independent thorium minerals in pyroxene, scapolite, olivine and carbonate, etc. The magnitude of thorium minerals ranges from 0.2 mm to 0.5 mm, which has no other paragenetic and associated metallic mineral. With the assay of electric probe, the main components of thorium minerals are ThO2, UO2 and PbO. According to characteristics of its components and observation under microscope, it's concluded that thorium mineralization mainly contains thorianite and uranothorianite. There is no obvious pyrometasomatic phenomenon in ore. It's inferred that thorium mineralization is formed in the early stage of skarnization. (authors)

  5. Isotope geology characteristics and genesis of the Qiwan zinc deposits, Zhejiang province

    International Nuclear Information System (INIS)

    Geologic characteristics, ore-controlling factors, mineralization age and sources are studied for the Qiwan zinc deposits in Zhuji County, Zhejiang Province. A skarns type mineralization of magmatic hydrothermal percolation genesis is proposed. The ore-forming hydrothermal solution was derived from the remelted magma at the crystalline basement. Mineralization was determined as Caledonian, and the Variscan-Early Indosinian events caused its further activation and enrichment

  6. Petrogenesis of the Zhangmatun gabbro in the Ji'nan complex, North China Craton: Implications for skarn-type iron mineralization

    Science.gov (United States)

    Xie, Qiuhong; Zhang, Zhaochong; Hou, Tong; Santosh, M.; Jin, Ziliang; Han, Liu; Cheng, Zhiguo

    2015-12-01

    The Zhangmatun gabbro is part of the Ji'nan complex in the North China Craton. It is spatially and temporally associated with the Zhangmatun skarn-type high-grade iron deposit. U-Pb dating of zircons from the Zhangmatun gabbro yielded an age of 130.2 ± 1.8 Ma, indicating the emplacement time as Early Cretaceous. The Zhangmatun gabbro displays porphyritic texture with plagioclase and clinopyroxene as the major phenocryst phases, together with minor biotite, hornblende, and magnetite. The rocks show a restricted range of SiO2 (50.1-52.7 wt.%) and Al2O3 (14.7-16.0 wt.%), low TiO2 (0.69-0.86 wt.%), relatively variable FeOT (2.87-8.62 wt.%), high MgO (6.50-8.01 wt.%) and Na2O (3.36-5.13 wt.%). The gabbro is also characterized by marked enrichment of LREEs and other LILEs (e.g., Rb, Sr and Ba), and strong depletion in HFSEs (e.g., Nb, Ta, Ti, Zr and Hf), similar to arc-related magma. The plagioclase and clinopyroxene from the Ji'nan gabbro, Zhangmatun gabbro, as well as Yaoshan and Huashan gabbroic diorite exhibit higher oxygen isotopes than those of the primitive mantle, indicating involvement of crustal materials. The similarity in geology, geochronology and petrology of these rocks suggests that they are co-magmatic. The parent magma of the Zhangmatun gabbro was produced by partial melting of amphibole-bearing spinel lherzolite in the upper mantle which has been modified by the lower crustal materials beneath the North China Craton. In combination with the Sr-Nd isotopic compositions of the Zhangmatun gabbro, we recognize EMI-type mantle source beneath the Ji'nan area. Moreover, the relatively high values as well as the relatively large variation of εHf(t) (-9.1 to +1.8) imply that asthenospheric material was also involved in the mantle-derived melt. The formation of iron concentration in the hydrothermal fluids is attributed to the exsolution of Fe-rich magmatic fluids and leaching from the solidified Zhangmatun gabbro at the retrograde alteration stage.

  7. Cristallochimie et propriétés physiques des borates magnésiens des skarns de la province banatitique de Roumanie

    OpenAIRE

    Marincea, Stephan

    1998-01-01

    L'étude apporte des nouvelles données sur les borates magnésiens de cinq gites de skarns de Roumanie : Baita Bihor, Pietroasa, Ocna de Fier, Masca-Baisoara et Cacova Ierii. Les aires de skarn sont developpées autour des intrusions calco-alcalines d'âge crétacé supérieur - paléogène, connues sous le nom collectif de banatites. Les borates qui ont été identifiés, à savoir la ludwigite, la kotoite, la szaibelyite, la suanite et la fluoborite sont caractéristiques d'une association géochimique tr...

  8. Centrality, Rapidity And Transverse-Momentum Dependence of Cold Nuclear Matter Effects on J/Psi Production in D Au, Cu Cu And Au Au Collisions at S(NN)**(1/2)

    Energy Technology Data Exchange (ETDEWEB)

    Ferreiro, E.G.; /Santiago de Compostela U.; Fleuret, F.; /Ecole Polytechnique; Lansberg, J.P.; /Ecole Polytechnique /SLAC; Rakotozafindrabe, A.; /SPhN, DAPNIA, Saclay

    2011-11-11

    We have carried out a wide study of Cold Nuclear Matter (CNM) effects on J/{Psi} = production in dAu, CuCu and AuAu collisions at {radical}s{sub NN} = 200 GeV. We have studied the effects of three different gluon-shadowing parameterizations, using the usual simplified kinematics for which the momentum of the gluon recoiling against the J/{Psi} is neglected as well as an exact kinematics for a 2 {yields} 2 process, namely g + g {yields} J/{psi} + g as expected from LO pQCD. We have shown that the rapidity distribution of the nuclear modification factor R{sub dAu}, and particularly its anti-shadowing peak, is systematically shifted toward larger rapidities in the 2 {yields} 2 kinematics, irrespective of which shadowing parameterization is used. In turn, we have noted differences in the effective final-state nuclear absorption needed to fit the PHENIX dAu data. Taking advantage of our implementation of a 2 {yields} 2 kinematics, we have also computed the transverse momentum dependence of the nuclear modification factor, which cannot be predicted with the usual simplified kinematics. All the corresponding observables have been computed for CuCu and AuAu collisions and compared to the PHENIX and STAR data. Finally, we have extracted the effective nuclear absorption from the recent measurements of RCP in dAu collisions by the PHENIX collaboration.

  9. Charged-particle multiplicity and pseudorapidity distributions measured with the PHOBOS detector in Au+Au, Cu+Cu, d+Au, and p+p collisions at ultrarelativistic energies

    Science.gov (United States)

    Alver, B.; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Chetluru, V.; Decowski, M. P.; García, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kotuła, J.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Li, W.; Lin, W. T.; Loizides, C.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Sedykh, I.; Skulski, W.; Smith, C. E.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wadsworth, B.; Walters, P.; Wenger, E.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2011-02-01

    Pseudorapidity distributions of charged particles emitted in Au+Au, Cu+Cu, d+Au, and p+p collisions over a wide energy range have been measured using the PHOBOS detector at the BNL Relativistic Heavy-Ion Collider (RHIC). The centrality dependence of both the charged particle distributions and the multiplicity at midrapidity were measured. Pseudorapidity distributions of charged particles emitted with |η|<5.4, which account for between 95% and 99% of the total charged-particle emission associated with collision participants, are presented for different collision centralities. Both the midrapidity density dNch/dη and the total charged-particle multiplicity Nch are found to factorize into a product of independent functions of collision energy, sNN, and centrality given in terms of the number of nucleons participating in the collision, Npart. The total charged particle multiplicity, observed in these experiments and those at lower energies, assumes a linear dependence of (lnsNN)2 over the full range of collision energy of sNN=2.7-200 GeV.

  10. Near-side azimuthal and pseudorapidity correlations using neutral strange baryons and mesons in \\dAu, \\Cu and \\Au collisions at $\\sqrt{s_{NN}}$~=~200~GeV

    CERN Document Server

    Abelev, B; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Aparin, A; Arkhipkin, D; Aschenauer, E C; Attri, A; Averichev, G S; Bai, X; Bairathi, V; Barnby, L S; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bielcik, J; Bielcikova, J; Bland, L C; Bombara, M; Bordyuzhin, I G; Bouchet, J; Brandenburg, J D; Brandin, A V; Bunzarov, I; Butterworth, J; Caines, H; Sánchez, M Calderón de la Barca; Campbell, J M; Cebra, D; Chakaberia, I; Chaloupka, P; Chang, Z; Chatterjee, A; Chattopadhyay, S; Chen, J H; Chen, X; Cheng, J; Cherney, M; Christie, W; Contin, G; Crawford, H J; Das, S; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; di Ruzza, B; Didenko, L; Dilks, C; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Eppley, G; Esha, R; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Federic, P; Fedorisin, J; Feng, Z; Filip, P; Fisyak, Y; Flores, C E; Fulek, L; Gagliardi, C A; Gaillard, L; Geurts, D Garand F; Gibson, A; Girard, M; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, S; Gupta, A; Guryn, W; Hamad, A I; Hamed, A; Haque, R; Harris, J W; He, L; Heppelmann, S; Hirsch, A; Hoffmann, G W; Horvat, S; Huang, T; Huang, X; Huang, B; Huang, H Z; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Jentsch, A; Jia, J; Jiang, K; Jones, P G; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Khan, Z H; Kikoła, D P; Kisel, I; Kisiel, A; Kochenda, L; Koetke, D D; Kosarzewski, L K; Kraishan, A F; Kravtsov, P; Krueger, K; Kumar, L; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; Li, X; Li, C; Li, Y; Li, W; Lin, T; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, R; Ma, G L; Ma, Y G; Ma, L; Magdy, N; Majka, R; Manion, A; Margetis, S; Markert, C; Matis, H S; McDonald, D; McKinzie, S; Meehan, K; Mei, J C; Minaev, N G; Mioduszewski, S; Mishra, D; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nattrass, C; Nasim, Md; Nayak, T K; Nigmatkulov, G; Niida, T; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Okorokov, V A; Olvitt, D; Page, B S; Pak, R; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlik, B; Pei, H; Perkins, C; Pile, P; Pluta, J; Poniatowska, K; Porter, J; Posik, M; Poskanzer, A M; Pruthi, N K; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, S; Raniwala, R; Ray, R L; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, A; Sharma, B; Sharma, M K; Shen, W Q; Shi, Z; Shi, S S; Shou, Q Y; Sichtermann, E P; Sikora, R; Simko, M; Singha, S; Skoby, M J; Smirnov, N; Smirnov, D; Solyst, W; Song, L; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stepanov, M; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Summa, B; Sun, Z; Sun, X M; Sun, Y; Surrow, B; Svirida, D N; Tang, Z; Tang, A H; Tarnowsky, T; Tawfik, A; Thäder, J; Thomas, J H; Timmins, A R; Tlusty, D; Todoroki, T; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Tripathy, S K; Tsai, O D; Ullrich, T; Underwood, D G; Upsal, I; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Varma, R; Vasiliev, A N; Vertesi, R; Videbæ, F; Vokal, S; Voloshin, S A; Vossen, A; Wang, F; Wang, G; Wang, J S; Wang, H; Wang, Y; Webb, G; Webb, J C; Wen, L; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y; Xiao, Z G; Xie, W; Xie, G; Xin, K; Xu, Y F; Xu, Q H; Xu, N; Xu, H; Xu, Z; Xu, J; Yang, S; Yang, Y; Yang, C; Yang, Q; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I -K; Yu, N; Zbroszczyk, H; Zha, W; Zhang, X P; Zhang, Y; Zhang, J; Zhang, S; Zhang, Z; Zhang, J B; Zhao, J; Zhong, C; Zhou, L; Zhu, X; Zoulkarneeva, Y; Zyzak, M

    2016-01-01

    We present measurements of the near-side of triggered di-hadron correlations using neutral strange baryons ($\\Lambda$, $\\bar{\\Lambda}$) and mesons ($K^0_S$) at intermediate transverse momentum (3~$<$~$p_T$~$<$~6~GeV/$c$) to look for possible flavor and baryon/meson dependence. This study is performed in $d$+Au, Cu+Cu and Au+Au collisions at $\\sqrt{s_{{NN}}}$ = 200 GeV measured by the STAR experiment at RHIC. The near-side di-hadron correlation contains two structures, a peak which is narrow in azimuth and pseudorapidity consistent with correlations due to jet fragmentation, and a correlation in azimuth which is broad in pseudorapidity. The particle composition of the jet-like correlation is determined using identified associated particles. The dependence of the conditional yield of the jet-like correlation on the trigger particle momentum, associated particle momentum, and centrality for correlations with unidentified trigger particles are presented. The neutral strange particle composition in jet-like ...

  11. Geochemistry and petrology of the indium-bearing polymetallic skarn ores at Pitkäranta, Ladoga Karelia, Russia

    Science.gov (United States)

    Valkama, M.; Sundblad, K.; Cook, N. J.; Ivashchenko, V. I.

    2016-08-01

    The historic mining district of Pitkäranta in the Ladoga region, Fennoscandian Shield, was exploited for Fe, Cu, Zn, Pb, Sn and Ag in the nineteenth to twentieth centuries. The Pitkäranta region is dominated by Palaeoproterozoic supracrustal rocks, which, together with gneissic Archaean dome structures, constitute an allochthonous terrane complex that amalgamated to the Archaean continent during the Svecokarelian orogeny at 1.9-1.8 Ga. This crustal complex was intruded by 1.8 Ga Late orogenic granites, 1.54 Ga anorogenic rapakivi granites and 1.45 Ga dolerites. The polymetallic skarn ores of Pitkäranta extend over a 25-km-long zone in Palaeoproterozoic supracrustal rocks and formed from hydrothermal solutions, which emanated from the anorogenic rapakivi granites and reacted with marble layers. Four major ore types are recognised after the dominating metal: Fe, Cu, Sn and Zn, respectively. These types are not restricted to individual mines or mine fields but represent end members in zonation patterns within each ore body. Pitkäranta was the second discovery site in the world for indium but has been without modern documentation for more than 75 years. The indium contents in the ores are up to 600 ppm, in most cases sphalerite-hosted. The only roquesite-bearing sample in this study had an indium grade of 291 ppm and an In/Zn ratio of 51 (close to the criteria for the limiting conditions for creating an In-rich mineral). The Pitkäranta ores have a potential for future small-scale exploitation, but all such plans are hampered by high contents if Bi, Cd and As.

  12. Geochemistry and petrology of the indium-bearing polymetallic skarn ores at Pitkäranta, Ladoga Karelia, Russia

    Science.gov (United States)

    Valkama, M.; Sundblad, K.; Cook, N. J.; Ivashchenko, V. I.

    2016-02-01

    The historic mining district of Pitkäranta in the Ladoga region, Fennoscandian Shield, was exploited for Fe, Cu, Zn, Pb, Sn and Ag in the nineteenth to twentieth centuries. The Pitkäranta region is dominated by Palaeoproterozoic supracrustal rocks, which, together with gneissic Archaean dome structures, constitute an allochthonous terrane complex that amalgamated to the Archaean continent during the Svecokarelian orogeny at 1.9-1.8 Ga. This crustal complex was intruded by 1.8 Ga Late orogenic granites, 1.54 Ga anorogenic rapakivi granites and 1.45 Ga dolerites. The polymetallic skarn ores of Pitkäranta extend over a 25-km-long zone in Palaeoproterozoic supracrustal rocks and formed from hydrothermal solutions, which emanated from the anorogenic rapakivi granites and reacted with marble layers. Four major ore types are recognised after the dominating metal: Fe, Cu, Sn and Zn, respectively. These types are not restricted to individual mines or mine fields but represent end members in zonation patterns within each ore body. Pitkäranta was the second discovery site in the world for indium but has been without modern documentation for more than 75 years. The indium contents in the ores are up to 600 ppm, in most cases sphalerite-hosted. The only roquesite-bearing sample in this study had an indium grade of 291 ppm and an In/Zn ratio of 51 (close to the criteria for the limiting conditions for creating an In-rich mineral). The Pitkäranta ores have a potential for future small-scale exploitation, but all such plans are hampered by high contents if Bi, Cd and As.

  13. Mineralogy, geochemistry and origin of Zafarabad iron deposit based on REE and trace elements of magnetite

    Directory of Open Access Journals (Sweden)

    Mehrdad Barati

    2013-10-01

    Full Text Available Zafarabad iron deposit is located northwest of Divandareh, in the northern margin of Sanandaj-Sirjan plutonic-metamorphic zone. The deposit is in lentoid to tubular shape, within a shear zone and occrrued in host rocks of calc-schist and limestone. Magnetite with massive, cataclastic and replacement textures are the main phases, while pyrite and other sulfide minerals are found. Major and trace elements are measured by ICP-MS and ICP-AES methods. Based on some ratios of trace elements in the ore samples and (Ti+V vs. Cal+Al+Mn and Ti+V vs. Ni/(Cr+Mn diagrams which are used for classification of iron deposit types, Zafarabad iron deposit fall in the range of skarn deposits. Spider diagrams show a steady decline from LREE to HREE elements with Eu (mean value of 0.06 ppm and Ce (mean value of 0.94 ppm negative anomalies. Comparing the distribution patterns of REE for the Zafarabad magnetites with those of various types of iron deposits shows that the REE pattern for Zafarabad is similar to these deposits. Analysis of calculated parameters for REE shows that the hydrothermal fluids responsible for mineralization are mainly of magmatic origin through fractionation and crystallization processes of a deep iron rich fluid phase and its emplacement within the carbonate rocks, forming iron skarn.

  14. Remote Sensing Technology for Identification of Alteration Information of Gold Deposits in the Eastern Tianshan Area, Xinjiang

    Institute of Scientific and Technical Information of China (English)

    FU Shuixing; ZHANG Shoulin; LI Chunxia; FENG Jianzhong; FANG Tonghui; SUN Baosheng

    2004-01-01

    Based on specific well-exposed rocks useful for high-quality remote sensing interpretation in the goldprospecting area in the eastern Tianshan, this paper gives a detailed description of a remote sensing model for metallogenic prediction. The model reveals that multi-spectral remote sensing data are integrated with high-resolution remote sensing data, and enhanced extraction and visual description of weak remote sensing information are used for prospecting. This model has tested in the given gold deposit, and used successfully in Au-Cu prospecting in the Kalatage area.

  15. Geochemical characteristics and significance of major elements,trace elements and REE of NM copper polymetal deposit in Laos

    Institute of Scientific and Technical Information of China (English)

    贾润幸; 方维萱; 胡瑞忠

    2010-01-01

    The NM copper polymetal deposit is located in the middle north part of the Truong Son metallogenic belt in Laos,which is the skarn-typed deposit and located in the contact between Indosinian granite and Lower Carboniferous limestone.All the ore-bodies in NM deposit can be divided into four types according to their occurrences:I copper ore-body as the massive restite developed in inner contact near the granite in north part;Ⅱ-1 zinc-copper ore body and Ⅱ-2 copper-iron ore body developed within contact betwee...

  16. Metallogenic tectonic geochemical harrier and metalloogenic egularity of Dongdusitai Au-Cu deposit%东杜斯泰金铜矿成矿构造地球化学障及成矿规律

    Institute of Scientific and Technical Information of China (English)

    邓洪涛

    2001-01-01

    @@东杜斯泰含金铜矿位于精河县境内,为第七地质大队2000年在进行1:5万化探普查、异常查证时发现,经初步地质评价认为该含矿构造-岩浆活动频繁,构造地球化学控矿特征明显,具金铜找矿意义。

  17. Re-Os isotopic data for molybdenum from Hejiangkou tungsten and tin polymetallic deposit in Chenzhou and its geological significance

    Institute of Scientific and Technical Information of China (English)

    刘德波; 杨柳; 邓湘伟; 戴雪玲; 王雄军; CHONGkhaiyuen; 杜高峰; 魏和平

    2016-01-01

    Hejiangkou W−Sn-polymetallic deposit is a newly found deposit in Xitian ore field, one of the important and large scale W−Sn-polymetallic ore fields in the middle segment of Nanling metallogenic zone. Re−Os isotope dating was used on three molybdenite samples from Hejiangkou deposit to determine the ore forming period. The result is (224.9±2.6)Ma−(225±3.1)Ma and isochron age is (225.5±3.6)Ma. The field geological observations, geochronological data and optical petrography indicated that Hejiangkou deposit underwent multi-period of superimposed mineralization. It can be differentiated into three periods composed of six mineralization stages. The first period is the initial period for hydrothermal metasomatism and metal element enrichment during Indosinian Epoch. Further enrichment, strong brittle fracturing and hydrothermal metasomatism, remobilization and superimposition happened in the second period, during early Yanshanian. It is the major mineralization period of Hejiangkou deposit and can be subdivided into four mineralization stages, namely the skarn stage, oxide stage, high-temperature sulfide stage and low-temperature sulfide stage. And the third period is the mineralization period of a porphyry-skarn system related to the emplacement of the granite porphyry dyke. As minerogenic epoch of Hejiangkou deposit is similar with Hehuaping deposit, they show the possibility of Indosinian mineralization event in Nanling metallogenic zone. It can be an important perspective in any future mineral exploration in the same metallogenic zone.

  18. Modelo genéticode los skarns de Fe de Vegas Peladas, Mendoza Genetic model of the Vegas PeladasFe-sakarns, Mendoza, Argentina

    OpenAIRE

    María Josefina Pons; Marta Franchini; Graciela Mas; FranciscoJavier Ríos

    2009-01-01

    Datos de inclusiones fluidas(IF) indican que el skarn de Fe relacionado al plutón diorítico de VegasPeladas se originó a 3,5 km de profundidad, bajo presiones litostáticas de 950bares y a expensas de fluidos muy salinos (hasta 70% NaCl eq.) de altatemperatura (670-400°C). Es muy factible que estos fluidos ricos en NaCl ± KCl± FeCln ± hematita junto con vapor se hayan formado por la inmiscibilidad defluidos magmáticos de salinidad baja (6-8% NaCl eq.). Los datos isotópicos delagua en equilibri...

  19. Late Paleozoic base and precious metal deposits,East Tianshan, Xinjiang, China: Characteristics and geodynamic setting

    Institute of Scientific and Technical Information of China (English)

    JingwenMao; RichardJ.Goldfarb; YitianWang; CraigJ.Hart; ZhiliangWang; JianminYang

    2005-01-01

    The East Tianshan is a remote Gobi area located in eastern Xinjiang, northwestern China. In the past several years, a number of gold, porphyry copper, and Fe(-Cu) and Cu-Ag-Pb-Zn skarn deposits have been discovered there and are attracting exploration interest.The East Tianshan is located between the Junggar block to the north and early Paleozoic terranes of the Middle Tianshan to the south. It is part of a Hercynian orogen with three distinct E-W-trending tectonic belts: the Devonian-Early Carboniferous Tousuquan-Dananhu island arc on the north and the Carboniferous Aqishan -Yamansu rift basin to the south, which are separated by rocks of the Kanggurtag shear zone. The porphyry deposits, dated at 322 Ma, are related to the late evolutionary stages of a subduction-related oceanic or continental margin arc. In contrast, the skarn, gold, and magmatic Ni-Cu deposits are associated with post-colli-sional tectonics at ca. 290-270 Ma. These Late Carboniferous - Early Permian deposits are associated with large-scale emplacement and eruption of magmas possibly caused by lithosphere delamination and rifting within the East Tianshan.

  20. Modelo genéticode los skarns de Fe de Vegas Peladas, Mendoza Genetic model of the Vegas PeladasFe-sakarns, Mendoza, Argentina

    Directory of Open Access Journals (Sweden)

    María Josefina Pons

    2009-06-01

    Full Text Available Datos de inclusiones fluidas(IF indican que el skarn de Fe relacionado al plutón diorítico de VegasPeladas se originó a 3,5 km de profundidad, bajo presiones litostáticas de 950bares y a expensas de fluidos muy salinos (hasta 70% NaCl eq. de altatemperatura (670-400°C. Es muy factible que estos fluidos ricos en NaCl ± KCl± FeCln ± hematita junto con vapor se hayan formado por la inmiscibilidad defluidos magmáticos de salinidad baja (6-8% NaCl eq.. Los datos isotópicos delagua en equilibrio con el granate (δ18O 7,2-8,5‰ y conla magnetita (4,8-7,9‰ confirman el origen magmático de estos fluidos.Debido a la interacción con la caja y a la formación del exoskarn degranate-clinopiroxeno, los fluidos redujeron isobáricamente sus temperaturas(hasta ~250°C. La continua exsolución de volátiles del magma y el sellado delos conductos de circulación de los fluidos por la precipitación de lossilicatos (magnetita del exoskarn y de la alteración del borde delplutón, generaron sobrepresiones, el fracturamiento de las rocas y laebullición del fluido. Bajo condiciones hidrostáticas, el aumento de lapermeabilidad permitió el ingreso de las aguas externas al sistema que semezclaron con los fluidos magmáticos provocando el reemplazo de los silicatospor minerales hidratados, cuarzo (con valores δ18O del fluidode -0,55 a 4,5‰ y la precipitación masiva de óxidos de hierro. Losregistros en inclusiones fluidas señalan temperaturas de 420° a 320°C,presiones hidrostáticas de 325 a 125 bares y fluidos menos salinos (41,6-23%NaCl eq. para este estadio. La disminución de la temperatura y de la salinidadfueron los factores principales que favorecieron la precipitación de la mena deFe. Las venillas tardías que cortan a las alteraciones anteriores se formaron alas temperaturas (165-315°C y salinidades (8,41 y 13,51% NaCl eq. más bajasdel sistema. Los valores δ18O del agua en equilibrio con elepidoto (-4,66 a 0,19‰ y con la calcita

  1. Types and geological characteristics of iron deposits in China

    Science.gov (United States)

    Li, Hou-Min; Li, Li-Xing; Yang, Xiu-Qing; Cheng, Yan-Bo

    2015-05-01

    China has the largest global demand for iron ore resources, with more than 50% of its demand presently being met from foreign sources. Iron resources are abundant in China (ca. 80 billion tons of proven iron ores), but high-grade ores are scarce. Most iron deposits in China are low in grade, with an average grade of 30.62% TFe. The iron deposits in China are divided into six types: sedimentary-metamorphic, magmatic Fe-Ti-(V), volcanic rock-hosted, contact metasomatic-hydrothermal (mostly skarn), sedimentary, and weathering-leaching type. Sedimentary-metamorphic iron deposits, which are mainly distributed in the North China Craton, are dominated by highly metamorphosed and deformed BIF-related iron deposits. Although these ores average only 30.35% TFe, their coarse-grained magnetite is easily recovered during processing. Sedimentary-metamorphic iron deposits are the most common of the iron deposit types in China and account for approximately 56.3% of the proven ore reserves in the country. Iron skarn deposits in China occur along or near the contact zones between Mesozoic intermediate-felsic, medium- to shallow-level intrusions and carbonate country rocks. They are one of the most important suppliers of high-grade magnetite ores in China. Magmatic Fe-Ti-(V) deposits, which formed in Proterozoic basement rocks during the late Paleozoic Hercynian orogeny, are hosted by mafic-ultramafic complexes with Ti-V-rich magnetite as the major iron ore mineral. Volcanic rock-hosted iron deposits are divided into those hosted by marine and continental volcanic rocks, with magnetite as the main ore mineral in both. Marine volcanic rock-hosted iron deposits are mainly distributed in late Paleozoic rocks of the Altaishan and Tianshan Mountains in the Xinjiang Uygur Autonomous Region. Continental volcanic rock-hosted iron deposits are mainly distributed in the Yanshanian (late Mesozoic) Na-rich intermediate-mafic rocks of the Ningwu and Luzong basins in the Middle-Lower Yangtze River

  2. Dual origins of epigenetic hydrothermal Ba and Pb-Zn deposits in the Chanarcillo group, Atacama Region, Chile: An example in the Quebrada Galena

    International Nuclear Information System (INIS)

    In the Lower Cretaceous Chanarcillo Group, in the Atacama Region, structurally-controlled vein, disseminated and stratiform base metal mineralization is mainly associated with the intrusive and metasomatic activity of the Cretaceous magmatic arc (Chilean Iron Belt). A distinct group of epigenetic base metal stratiform deposits, involving moderate temperature fluids in part associated with hydrocarbons, is best explained by basinal-scale processes (Cisternas et al., 1999; Lieben et al., 1999). In this study, a dual origin, with more or less prominent involvement of Cretaceous magmatism, has been evidenced for carbonate-hosted Pb-Zn±Ag and Ba deposits and occurrences in the Chanarcillo Group. In the Quebrada Galena (28o05'S, 70o30'W) the presence, within a few kilometers, of such different Ba and Pb-Zn ore occurrence types provides an opportunity to study the relative timing and the possible genetic links between the different mineralizing processes. With this purpose, we firstly describe two deposits with the most contrasting characteristics, the Maria Cristina Zn-Pb-(Ba) skarn deposit, and the Mamina stratiform barite deposit. In a second step, Ba and Pb-Zn deposits and occurrences with intermediate characteristics could help to unravel the relations between these oreforming systems. Fluid inclusions microthermometry, and sulfur and strontium isotopes are used to provide further insight into the nature of ore-forming fluids and source of ore-forming elements, and 40Ar/39Ar dating to constrain the age of the Zn-Pb skarn mineralization (au)

  3. Mode of formation of hibonite (CaAl12O19) within the U-Th skarns from the granulites of S-E Madagascar

    Science.gov (United States)

    Rakotondrazafy, Michel A. F.; Moine, B.; Cuney, M.

    1996-03-01

    In Madagascar, hibonite occurs as a rather frequent mineral within thorianite-bearing skarns which are widespread in the Pan African granulitic formations constituting the S-E part of the Island (Tranomaro area). In these skarns, leucocratic segregations made up of CO3-scapolite to meionite (Anequivalent=89 95% which implies T≥850° C), spinel and corundum were formed at stage 1 of metasomatism in a titanite-bearing matrix consisting of scapolite (Aneq=77 88) and aluminous diopside. During stage 2 of metasomatism, scapolite from the lenses were altered to anorthite+calcite while the less calcic scapolite remained stable which indicates T≈800° C. Hibonite crystallized at the expense of corundum and spinel. Expressed as mol% of the CaAl12O19/Ca(Al10TiR2+)O19/REE(Al11R2+)O19 [+Th (Al10R2+ 2)O19] end-members ( R 2+=Mg, Fe2+, Zn2+; Al=Al, Fe3+; Ti=Ti, Si), its composition varies from 26/72/2 to 50/23/27. The ideal activity of the CaAl12O19 component is about 0.25. Fluid inclusions in corundum, hibonite and anorthite are composed of nearly pure CO2. In corundum, the isochores for primary inclusions are in agreement with the P-T estimates for regional metamorphism and stage 1 metasomatism ( T≈850° C, P≈5 kbar). Inclusions with the highest density in hibonite and anorthite constrain P to about 3 3.5 kbar for T=800° C. Thermodynamic calculations indicate that, in addition to a low activity of CaAl12O19, stability of hibonite in equilibrium with anorthite and calcite implies an extremely low activity of silica (below the zircon-baddeleyite buffer). By contrast the activity of CO2 may be high, in agreement with the observed fluid compositions. These results are corroborated by a short comparison with the other granulite occurrences of hibonite in Tanzania and South India.

  4. Nature, diversity of deposit types and metallogenic relations of South China

    Science.gov (United States)

    Zaw, K.; Peters, S.G.; Cromie, P.; Burrett, C.; Hou, Z.

    2007-01-01

    The South China Region is rich in mineral resources and has a wide diversity of deposit types. The region has undergone multiple tectonic and magmatic events and related metallogenic processes throughout the earth history. These tectonic and metallogenic processes were responsible for the formation of the diverse styles of base and precious metal deposits in South China making it one of the resource-rich regions in the world. During the Proterozoic, the South China Craton was characterised by rifting of continental margin before eruption of submarine volcanics and development of platform carbonate rocks, and the formation of VHMS, stratabound copper and MVT deposits. The Phanerozoic metallogeny of South China was related to opening and closing of the Tethyan Ocean involving multiple orogenies by subduction, back-arc rifting, arc-continent collision and post-collisional extension during the Indosinian (Triassic), Yanshanian (Jurassic to Cretaceous) and Himalayan (Tertiary) Orogenies. The Late Palaeozoic was a productive metallogenic period for South China resulting from break-up and rifting of Gondwana. Significant stratabound base and precious metal deposits were formed during the Devonian and Carboniferous (e.g., Fankou and Dabaoshan deposits). These Late Palaeozoic SEDEX-style deposits have been often overprinted by skarn systems associated with Yanshanian magmatism (e.g., Chengmenshan, Dongguashan and Qixiashan). A number of Late Palaeozoic to Early Mesozoic VHMS deposits also developed in the Sanjiang fold belt in the western part of South China (e.g., Laochang and Gacun). South China has significant sedimentary rock-hosted Carlin-like deposits, which occur in the Devonian- to Triassic-aged accretionary wedge or rift basins at the margin of the South China Craton. They are present in a region at the junction of Yunnan, Guizhou, and Guangxi Provinces called the 'Southern Golden Triangle', and are also present in NW Sichuan, Gansu and Shaanxi, in an area known as

  5. Proton induced X-ray emission and proton induced gamma ray emission analysis in geochemical exploration for gold and base metal deposits

    Energy Technology Data Exchange (ETDEWEB)

    Pwa, Aung E-mail: a_pwa@postoffice.utas.edu.au; Siegele, R.; Cohen, D.D.; Stelcer, E.; Moort, J.C. van

    2002-05-01

    Proton induced X-ray emission (PIXE) and proton induced gamma ray emission (PIGME) analysis has been used in geochemical exploration to determine various elements in rocks and regolith in relation to gold and base metal mineralisation. Elements analysed by PIXE include K, Fe, Ca, Ti, Mn, Cl, Ga, Rb, Sr, Zr, Y, Nb, Cu, Zn, Pb, Ni, As, V and Mo, and those by PIGME are Al, Na, Mg, F and Li. One of our research areas is Cobar, northwest of New South Wales, Australia. The study areas include the McKinnons and Peak gold deposits, the Wagga Tank base metal deposit and Lower Tank prospect, northeast of the CSA mine. Au, Cu, Zn, Pb, As and Ni are elevated as ore indicators near and around the ore deposits while K, Al, Ca, Na, Ti, Rb, Sr, Ga and V are depleted due to feldspar and mica destruction during alteration.

  6. Proton induced X-ray emission and proton induced gamma ray emission analysis in geochemical exploration for gold and base metal deposits

    International Nuclear Information System (INIS)

    Proton induced X-ray emission (PIXE) and proton induced gamma ray emission (PIGME) analysis has been used in geochemical exploration to determine various elements in rocks and regolith in relation to gold and base metal mineralisation. Elements analysed by PIXE include K, Fe, Ca, Ti, Mn, Cl, Ga, Rb, Sr, Zr, Y, Nb, Cu, Zn, Pb, Ni, As, V and Mo, and those by PIGME are Al, Na, Mg, F and Li. One of our research areas is Cobar, northwest of New South Wales, Australia. The study areas include the McKinnons and Peak gold deposits, the Wagga Tank base metal deposit and Lower Tank prospect, northeast of the CSA mine. Au, Cu, Zn, Pb, As and Ni are elevated as ore indicators near and around the ore deposits while K, Al, Ca, Na, Ti, Rb, Sr, Ga and V are depleted due to feldspar and mica destruction during alteration

  7. Re sbnd Os dating of molybdenites from ore deposits in Japan: Implication for the closure temperature of the Re sbnd Os system for molybdenite and the cooling history of molybdenum ore deposits

    Science.gov (United States)

    Suzuki, Katsuhiko; Shimizu, Hiroshi; Masuda, Akimasa

    1996-08-01

    Rhenium and Osmium abundances were determined on molybdenites from eighteen ore deposits in Japan; fifteen vein-type, a skarn-type, a greisen-type, and a pegmatite-type deposit. Re sbnd Os ages obtained for molybdenites from northeastern, central, and southwestern Japan are 100-130 Ma, 50-75 Ma, and ca. 10 Ma, respectively, reflecting the ages of regional igneous activities in individual areas. For vein-type ore deposits, Re sbnd Os ages for molybdenites agree with Rb sbnd Sr whole-rock ages of host granitoids, while they are 3-12 Ma older than K sbnd Ar mineral ages of the host rocks. On the other hand, Re sbnd Os ages of molybdenites from skarn-, pegmatite-, and greisen-type ore deposits agree with K sbnd Ar ages of the host rocks. The comparison of Re sbnd Os ages for molybdenites with Rb sbnd Sr and K sbnd Ar ages of host rocks in vein-type deposits suggests that Re sbnd Os closure temperature for vein molybdenite is close to whole-rock Rb sbnd Sr closure temperature for host granitic rocks, i.e., roughly estimated to be around 500°C, and higher than K sbnd Ar closure temperature for host granodiorites, i.e., 230-370°C, if the thermal history of vein molybdenites is essentially equivalent to that of host rocks. One possible explanation for age discrepancies of 3-12 Ma between Re sbnd Os ages for molybdenites and K sbnd Ar ages for the wall rocks, observed in vein-type molybdenum deposits, is that later thermal events after formation of molybdenum ores may reset K sbnd Ar ages. Hydrothermal alteration might have occurred in such a temperature condition as to disturb K sbnd Ar mineral systems in wall rocks and made them younger but not the Re sbnd Os system in molybdenite. The other explanation might be that the age discrepancies correspond to a cooling interval from ca. 500 to 300°C of host granitoid. On the other hand, the agreement of Re sbnd Os ages of molybdenites and K sbnd Ar ages of host rocks in skarn-, pegmatite-, and greisen-type deposits in this

  8. Daughter minerals in fluid inclusions of garnet and diopside from Tongguanshan Copper Deposit by SEM/EDS and LRM

    Institute of Scientific and Technical Information of China (English)

    Yuling Xie; Jiuhua Xu; Zengqian Hou; Zhusen Yang; Wenyi Xu; Yifeng Meng; Baohua Wang

    2004-01-01

    Tongguanshan copper deposit of Tongling large ore belt is one of the typical skarn copper deposits. Based on careful observation under microscope many daughter minerals including transparent ones and opaque ones have been distinguished in the fluid inclusions of garnet and diopside. The results of SEM/EDS (scanning electron microscope/energy dispersive spectrometer) and LRM (laser Raman microprobe) analysis show that these daughter minerals in garnet are sylvite, halite, sphalerite, chalcopyrite and carbonate. Sylvite daughter mineral is very popular in garnet and diopside. The existence of so much sylvite daughter mineral and other daughter minerals in the fluid inclusions indicates that the ore-forming fluid is of supper-high salinity and high potassium concentration. High potassium concentration in the fluid inclusions agrees with K-rich mesotype-acid rock and K-silicate alteration that occurred widely in this area. The daughter mineral assemblage in garnet and diopside is similar to the mineral assemblage of oreforming stage that followed skarn stage.

  9. K-Ar ages of sericites from the Kamioka mine and its significance in geochronology of the Kamioka deposits

    International Nuclear Information System (INIS)

    The Kamioka Pb-Zn deposits are pyrometasomatic and hydrothermal replacements in Hida metamorphic rocks. The ore is divided into two types: The early ''Mokuji'' ore that is skarn-type ore with hedenbergite and epidote and the later ''Shiroji'' ore with quartz and calcite. Sericite occurs in the Shiroji ore or as an alteration product in the wall rock of the Shiroji. K-Ar ages of five sericite samples were determined to be 65.3, 65.1, 66.1, 67.5 and 63.8 Ma. The results show that the Shiroji mineralization took place near the end of Cretaceous. The Mokuji mineralization may be not much older than the Shiroji. Recent finding of metamorphic skarn accompanied by pyrrhotite and sphalerite and crystalline limestone containing primary sphalerite and pyrrhotite suggests that the initial concentration of metals in this area can be traced back to a period prior to the Hida metamorphism. The K-Ar ages of sericites represent the time when the deposits took the present form. (author)

  10. Mineral Deposit Data for Epigenetic Base- and Precious-metal and Uranium-thorium Deposits in South-central and Southwestern Montana and Southern and Central Idaho

    Science.gov (United States)

    Klein, T.L.

    2004-01-01

    Metal deposits spatially associated with the Cretaceous Boulder and Idaho batholiths of southwestern Montana and southern and central Idaho have been exploited since the early 1860s. Au was first discovered in placer deposits; exploitation of vein deposits in bedrock soon followed. In 1865, high-grade Ag vein deposits were discovered and remained economically important until the 1890s. Early high-grade deposits of Au, Ag and Pb were found in the weathered portions of the veins systems. As mining progressed to deeper levels, Ag and Pb grades diminished. Exploration for and development of these vein deposits in this area have continued until the present. A majority of these base- and precious-metal vein deposits are classified as polymetallic veins (PMV) and polymetallic carbonate-replacement (PMR) deposits in this compilation. Porphyry Cu and Mo, epithermal (Au, Ag, Hg and Sb), base- and precious-metal and W skarn, W vein, and U and Th vein deposits are also common in this area. The world-class Butte Cu porphyry and the Butte high-sulfidation Cu vein deposits are in this study area. PMV and PMR deposits are the most numerous in the region and constitute about 85% of the deposit records compiled. Several types of syngenetic/diagenetic sulfide mineral deposits in rocks of the Belt Supergroup or their equivalents are common in the region and they have been the source of a substantial metal production over the last century. These syngenetic deposits and their metamorphosed/structurally remobilized equivalents were not included in this database; therefore, deposits in the Idaho portion of the Coeur d'Alene district and the Idaho Cobalt belt, for example, have not been included because many of them are believed to be of this type.

  11. Process Mineralogy of a Skarn Tungsten-Molybdenum Ore%夕卡岩型钨钼伴生矿工艺矿物学研究

    Institute of Scientific and Technical Information of China (English)

    洪秋阳; 梁冬云; 张莉莉

    2013-01-01

    The researches on a skarn tungsten-molybdenum ore by the internationally advanced MLA testing technology and traditional process mineralogy show that the grade of W and Mo is low with high comprehensive recycling value. The tungsten mainly occurs in the form of scheelite while the molybdenum principally exists as molybdenite, and the molybdenum as isomorphous addition existing in the lattice of scheelite accounts for 16.89%of the total molybdenum. The liberation degree of scheelite is close to 90%while that of molybdenite is less than 80%at the grinding fineness 62%-0.074 mm. The tungsten and molybdenum contained in the magnetic gangue minerals accounts for 2.8 % and 5.8 % respectively. Considering that the magnetic gangue minerals including andradite tremolite, diopside, etc account for about two-thirds of the total and are not closely intergrown with scheelite or molybdenite, pre-discarding these magnetic gangue minerals by high intensity magnetic separation is available so as to simplify the cleaning process of tungsten as well as molybdenum.%采用国际先进的MLA检测技术,结合传统工艺矿物学研究表明,某夕卡岩型钨钼伴生矿虽品位低,但综合回收价值较高。矿石中钨主要以含钼白钨矿矿物形式存在,以类质同象进入白钨矿晶格的钼占原矿总钼的16.89%。钼主要以辉钼矿矿物形式存在。当磨矿细度-0.074 mm占62%左右时,白钨矿单体解离近90%,而辉钼矿解离不到80%。钨、钼与本矿石中约占矿物总量三分之二的钙铁榴石、透辉石、透闪石等电磁性脉石连生关系不密切,分布于其中的钨、钼金属量分别仅2.8%、5.8%。因而可采用强磁选预先丢废而达到简化钨、钼精选。

  12. Mineralogy, chemistry of magnetite and genesis of Korkora-1 iron deposit, east of Takab, NW Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Maanijou

    2014-10-01

    Full Text Available Introduction There is an iron mining complex called Shahrak 60 km east of Takab town, NW Iran. The exploration in the Shahrak deposit (general name for all iron deposits of the area started in 1992 by Foolad Saba Noor Co. and continued in several periods until 2008. The Shahrak deposit comprising 10 ore deposits including Korkora-1, Korkora-2, Shahrak-1, Shahrak-2, Shahrak-3, Cheshmeh, Golezar, Sarab-1, Sarab-2, and Sarab-3 deposits Sheikhi, 1995 with total 60 million tons of proved ore reserves. The Fe grade ranges from 45 to 65% (average 50%. The ore reserves of these deposits vary and the largest one is Korkora-1 with 15 million tons of 55% Fe and 0.64% S. The Korkora-1 ore deposit is located in western Azarbaijan and Urumieh-Dokhtar volcanic zone, at the latitude of 36°21.8´, and longitude of 47°32´. Materials and methods Six thin-polished sections were made on magnetite, garnet, and amphibole for EPMA (Electron Probe Micro Analysis. EPMA was performed using a JEOL JXA-733 electron microprobe at the University of New Brunswick, Canada, with wavelength-dispersive spectrometers. Results and discussion Outcropped units of the area are calc-alkaline volcanics of rhyolite, andesite and dacite and carbonate rocks of Qom Formation in which intrusion of diorite to granodiorite and quartzdoirite caused contact metamorphism, alteration plus skarnization and formation of actinolite, talc, chlorite, phlogopite, quartz, calcite, epidote and marblization in the vicinity of the ore deposit. Iron mineralization formed at the contacts of andesite and dacite with carbonates in Oligo-Miocene. The study area consists of skarn, metamorphic rocks, and iron ore zones. The shape of the deposit is lentoid to horizontal with some alteration halos. The ore occurred as replacement, massive, disseminated, open-space filling and breccia. The ore minerals of the deposit include low Ti-magnetite (0.04 to 0.2 wt % Ti, minor apatite, and sulfide minerals such as pyrite

  13. Porphyry Cu-Au and associated polymetallic Fe-Cu-Au deposits in the Beiya Area, western Yunnan Province, south China

    Science.gov (United States)

    Xu, X.-W.; Cai, X.-P.; Xiao, Q.-B.; Peters, S.G.

    2007-01-01

    The Alkaline porphyries in the Beiya area are located east of the Jinshajiang suture, as part of a Cenozoic alkali-rich porphyry belt in western Yunnan. The main rock types include quartz-albite porphyry, quartz-K-feldspar porphyry and biotite-K-feldspar porphyry. These porphyries are characterised by high alkalinity [(K2O + Na2O)% > 10%], high silica (SiO2% > 65%), high Sr (> 400??ppm) and 87Sr/86Sr (> 0.706)] ratio and were intruded at 65.5??Ma, between 25.5 to 32.5??Ma, and about 3.8??Ma, respectively. There are five main types of mineral deposits in the Beiya area: (1) porphyry Cu-Au deposits, (2) magmatic Fe-Au deposits, (3) sedimentary polymetallic deposits, (4) polymetallic skarn deposits, and (5) palaeoplacers associated with karsts. The porphyry Cu-Au and polymetallic skarn deposits are associated with quartz-albite porphyry bodies. The Fe-Au and polymetallic sedimentary deposits are part of an ore-forming system that produced considerable Au in the Beiya area, and are characterised by low concentrations of La, Ti, and Co, and high concentrations of Y, Yb, and Sc. The Cenozoic porphyries in western Yunnan display increased alkalinity away from the Triassic Jinshajiang suture. Distribution of both the porphyries and sedimentary deposits in the Beiya area are interpreted to be related to partial melting in a disjointed region between upper mantle lithosphere of the Yangtze Plate and Gondwana continent, and lie within a shear zone between buried Palaeo-Tethyan oceanic lithosphere and upper mantle lithosphere, caused by the subduction and collision of India and Asia. ?? 2006 Elsevier B.V. All rights reserved.

  14. Structure Characteristics of Dickites in Copper-Gold Deposit

    Institute of Scientific and Technical Information of China (English)

    ZHONG Xianghua; LIU Yu; LIU Wenyuan

    2015-01-01

    Dickite as a type of clay mineral that is utilized in industries such as papers, ceramics, paints, cosmetics and fillers is widely distributed in Zijinshan (ZJS) Au-Cu deposit in southeastern China. In this paper, three types of dickites (i.e., transparent, translucent and opaque), which were selected by optical microscopy, were investigated by X-ray diffraction (XRD)-Rietveld method based on the EVA and TOPAS softwares. The results show that transparent dickite is lowly ordered and poorly crystallized. Compared to other two dickites, the transparent one has a lower value of DC in-dex and thinner average flake thickness alongc-axis. Furthermore, the crystal structure of transparent dickite has a greater number of distortions of [SiO4] tetrahedron and [AlO6] octahedron, compared to that of translucent and opaq-uedickites. The results by the XRD-Rietveld method were confirmed by field emission scanning electron microscopy (FESEM) and electron probe micro-analysis (EPMA). Therefore, transparent dickite with low degree of order and ir-regular particle shape is not suitable for use in ceramic industry.

  15. Oxygen isotope systematics of gem corundum deposits in Madagascar: relevance for their geological origin

    Science.gov (United States)

    Giuliani, Gaston; Fallick, Anthony; Rakotondrazafy, Michel; Ohnenstetter, Daniel; Andriamamonjy, Alfred; Ralantoarison, Théogène; Rakotosamizanany, Saholy; Razanatseheno, Marie; Offant, Yohann; Garnier, Virginie; Dunaigre, Christian; Schwarz, Dietmar; Mercier, Alain; Ratrimo, Voahangy; Ralison, Bruno

    2007-02-01

    The oxygen isotopic composition of gem corundum was measured from 22 deposits and occurrences in Madagascar to provide a gemstone geological identification and characterization. Primary corundum deposits in Madagascar are hosted in magmatic (syenite and alkali basalt) and metamorphic rocks (gneiss, cordieritite, mafic and ultramafic rocks, marble, and calc-silicate rocks). In both domains the circulation of fluids, especially along shear zones for metamorphic deposits, provoked in situ transformation of the corundum host rocks with the formation of metasomatites such as phlogopite, sakenite, and corundumite. Secondary deposits (placers) are the most important economically and are contained in detrital basins and karsts. The oxygen isotopic ratios (18O/16O) of ruby and sapphire from primary deposits are a good indicator of their geological origin and reveal a wide range of δ18O (Vienna Standard Mean Ocean Water) between 1.3 and 15.6‰. Metamorphic rubies are defined by two groups of δ18O values in the range of 1.7 to 2.9‰ (cordieritite) and 3.8 to 6.1‰ (amphibolite). “Magmatic” rubies from pyroxenitic xenoliths contained in the alkali basalt of Soamiakatra have δ18O values ranging between 1.3 and 4.7‰. Sapphires are classified into two main groups with δ18O in the range of 4.7 to 9.0‰ (pyroxenite and feldspathic gneiss) and 10.7 to 15.6‰ (skarn in marble from Andranondambo). The δ18O values for gem corundum from secondary deposits have a wide spread between -0.3 and 16.5‰. The ruby and sapphire found in placers linked to alkali basalt environments in the northern and central regions of Madagascar have consistent δ18O values between 3.5 and 6.9‰. Ruby from the placers of Vatomandry and Andilamena has δ18O values of 5.9‰, and between 0.5 and 4.0‰, respectively. The placers of the Ilakaka area are characterized by a huge variety of colored sapphires and rubies, with δ18O values between -0.3 and 16.5‰, and their origin is debated. A

  16. Re—Os Isotope Ages of Molybdenum Deposits in East Qinling and Their Significance

    Institute of Scientific and Technical Information of China (English)

    黄典豪; 杜安道; 等

    1995-01-01

    Dating of metallic ore deposits has been one of the problems concerned with by ore geologists for many years.The establishment of the Re-Os Isotope Laboratory at the Institute of Rock and Mineral Analysis,Chinese Academy of Geological Sciences, has provided us with a new technique to carry out geochronological studies of molybdenum ores.As one of the most important Re-bearing minerals, molybdenite contains almost no common osmium, but 187Os was derived completely from decay of 187Re, with 187Os content as the function of Re content in the mineral .An ID-ICP-MS technique has been used in this study,and Re-Os isotopic ages of several large molybdenum deposits of differ-ent types from the East Qinling molybdenum belt have been determined.It is indicated that the Huanglongpu carbonatite vein-type molybdenum-(lead) deposit has a Re-Os age corresponding to Indosinian,while the rest porphyry-type molybdenum deposits and porphyry-skarn-type molybdenum-(tungsten) deposits have Re-Os ages corresponding to Yenshanian.

  17. Tetrahedrite-Group Minerals in the Jinjitai Gold Deposit, Western Sichuan

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There are quite a few tetrahedrite-group minerals in the Jinjitai gold deposit, western Sichuan, which occur in an interstratified fractured zone of Middle Devonian carbonate rock series. The gold ore consists of pyrite, chalcopyrite, tetrahedrite-group minerals, galena, sphalerite and gold-silver series minerals, with an element association of Au-Cu-Ag-Pb-As-Sb-Bi. Electron microprobe analyses of the tetrahedrite-group minerals gave the following results: copper 40.04 to 42.27% (average 40.04%), iron 1.24 to 7.78% (average 4.13%), zinc 0.39 to 7.06% (average 3.58%), arsenic 5.41 to 17.40% (average 8.84%), antimony 2.70 to 20.46% (average 15.87%), and silver 0.02 to 0.73% (average 0.28%). The mineral varieties include zinc-antimony-tetrahedrite, iron-antimony-tetrahedrite, iron-tennatite and zincotennatite. These data show that there is a complete isomorphous series between Sb and As. From above downwards tetrahedrite varies from zinc- and antimony-rich to iron- and arsenic-rich compositions. Their occurrence and zonal features are very important for exploration of the same type of gold deposits in western Sichuan.

  18. Geophysical and geochemical exploration research on basic metallogenic conditions of unconformity-related uranium deposits in the south part of Kangdian earth's axis

    International Nuclear Information System (INIS)

    In order to find out the unconformity-related large and super large uranium-rich deposits and to explore the prospecting model for the unconformity-related uranium deposits, the geophysical and geochemical exploration on the basic metallogenic conditions of the unconformity-related uranium deposits in the south part of the Kangdian earth's axis has been carried out after the investigation and research into large amounts of information in combination with the analysis and contrasts of the aeromagnetic, aero-radiometric and gravity data. On the basis of synthesizing the airborne survey information, land-based geophysical and geochemical exploration, the physical nature of many types of rocks and the multi-element analytical and determining results of the U, Th, Au, Cu in the soil samples, the geophysical prospecting models on the unconformity-related uranium deposits in this area has been put forward, and two uranium metallogenic prospect areas and one uranium metallogenic prospect belt have been divided. These results have laid a good foundation for finding out the unconformity-related uranium deposits in this area

  19. Variation of Mo isotopes from molybdenite in high-temperature hydrothermal ore deposits

    Science.gov (United States)

    Mathur, Ryan; Brantley, S.; Anbar, A.; Munizaga, F.; Maksaev, V.; Newberry, R.; Vervoort, J.; Hart, G.

    2010-01-01

    Measurable molybdenum isotope fractionation in molybdenites from different ore deposits through time provides insights into ore genesis and a new technique to identify open-system behavior of Re-Os in molybdenites. Molybdenite samples from six porphyry copper deposits, one epithermal polymetallic vein deposit, four skarns, and three Fe-oxide Cu-Au deposits were analyzed. The δ97Mo‰ (where [InlineEquation not available: see fulltext.]) for all samples varied from 1.34 ± 0.09‰ to -0.26 ± 0.04‰. This is the largest molybdenum isotopic variation in molybdenite from high-temperature ore deposits recorded to date. δ97Mo‰ of molybdenite varies as a function of the deposit type and the rhenium and osmium concentrations of the samples. Isotope values for Mo also vary within the individual deposits. In general, molybdenites from porphyry copper deposits have the lightest values averaging 0.07 ± 0.23‰ (1 σ). Molybdenites from the other deposit types average 0.49 ± 0.26‰ (1 σ). The variations could be related to the fractionation of Mo into different mineral phases during the ore-forming processes. A comparison of the Mo isotope ratios and the Re-Os ages obtained from the same aliquot may possess a geochronological evaluation tool. Samples that yielded robust ages have different Mo isotopic compositions in comparison to samples that yielded geologically unreasonable ages. Another observed relationship between the Re-Os and Mo isotope data reveals a weak correspondence between Re concentration and Mo isotope composition. Molybdenites with higher concentrations of Re correspond to lighter Mo isotope values.

  20. Tourmaline from deposits of the Birgil'da-Tomino ore cluster, South Urals

    Science.gov (United States)

    Baksheev, I. A.; Plotinskaya, O. Yu.; Yapaskurt, V. O.; Vigasina, M. F.; Bryzgalov, I. A.; Groznova, E. O.; Marushchenko, L. I.

    2012-11-01

    Tourmalines from the Kalinovka porphyry copper deposit with epithermal bismuth-gold-basemetal mineralization and the Michurino gold-silver-base-metal prospect have been studied in the South Urals. Tourmaline from the Kalinovka deposit occurs as pockets and veinlets in quartz-sericite metasomatic rock and propylite. The early schorl-"oxy-schorl" [Fetot/(Fetot + Mg) = 0.66-0.81] enriched in Fe3+ is characterized by the homovalent isomorphic substitution of Fe3+ for Al typical of propylites at porphyry copper deposits. The overgrowing tourmalines of the second and third generations from propylite and quartz-sericite metasomatic rock are intermediate members of the dravite-magnesio-foitite solid solution series [Fetot/(Fetot + Mg) = 0.05-0.46] with homovalent substitution of Mg for Fe2+ and coupled substitution of X ▭ + YAl for XNa + YMg. These substitutions differ from the coupled substitution of YAl + WO2- for YFe2+ + WOH- in tourmaline from quartz-sericite rocks at porphyry copper deposits. At the Michurino prospect, the tourmaline hosted in the chlorite-pyrite-quartz veins and veinlets with Ag-Au-Cu-Pb-Zn mineralization is an intermediate member of the dravite-magnesio-foitite solid solution series [Fetot/(Fetot + Mg) = 0.20-0.31] with homovalent substitution of Mg for Fe2+ and coupled substitutions of X ▭ + YAl for XNa + YMg identical to that of late tourmaline at the Kalinovka deposit. Thus, tourmalines of the porphyry and epithermal stages are different in isomorphic substitutions, which allow us to consider tourmaline as an indicator of super- or juxtaposed mineralization.

  1. The Comprehensive Utilization of Wollastonite in Skarn Type Ore of Jiama Copper Polymetallic Deposit in Tibet%甲玛铜多金属矿矽卡岩型矿石中硅灰石的综合利用

    Institute of Scientific and Technical Information of China (English)

    雷传扬; 汪雄武; 苟正彬; 张强

    2012-01-01

    Many polymetallic components such as Cu、Mo、Pb、Zn、Au、Ag exist in the Jiama copper polymetallic ore in Tibet. At the same time the resources reserves of wollastonite are abundant,but it cannot be used synthetically, causing the economical loss and environmental pollution. According to the ore properties of the Jiama copper poly metallic ore and characteristics of mineral compositions of the tailings, the flowsheet of hand-sorting separation screening separating-flotation separation-ultrafine grinding was adopted for comprehensive recovery of wollastonite from the raw ore and tailings. According to the study it is believed that great economic and social benefit would be achieved by beneficiation tests, and degrading and practical application research to make full use of the advantage of mineral resources and develop products with high technological content and added value. The geologic character of wollasonite, the benefit, demand of market, the optional argument, the process and other aspects are roughly dis cussed in this paper. Also, some suggestions were offered for the comprehensive utilization of wollasonite.%西藏甲玛铜多金属矿赋存着Cu、Mo、Pb、Zn、Au、Ag等多种金属组分,同时伴生硅灰石,资源储量十分丰富,但尚未综合利用,造成经济损失且污染环境.根据甲玛铜多金属矿矿石性质和选矿尾砂矿物组成的特点,可采用手选-筛选分离-浮选分离-超细粉碎工序从原矿和尾砂中综合回收硅灰石.研究结果认为,加强硅灰石的选矿试验、精选分级、实际应用研究,充分利用资源优势,开发生产技术含量和附加值高的新产品,将为企业创造良好的经济效益和社会效益.本文就该矿床硅灰石的地质特征,硅灰石综合利用产生的效益、市场需求,可选性论证及大致流程等方面进行初步探讨,并提出了硅灰石综合利用建议.

  2. Compositional Variability of Rutile in Hydrothermal Ore Deposits

    Science.gov (United States)

    Clark, J. R.; Williams-Jones, A. E.

    2009-05-01

    Rutile is a relatively common accessory phase in many geological environments, and although it is almost always composed dominantly of TiO2, it is also associated with a wide range of minor and trace element substitutions. The most prominent minor elements that occur in rutile are Fe, Cr, V, Nb and Ta. Like Ti, the latter two elements are essentially immobile in most non-magmatic metallic ore deposits, and their concentrations in rutile are largely influenced by precursor mineral compositions. Iron, Cr and V concentrations vary considerably in rutile hosted by ore deposits, and reflect combinations of precursor mineral composition and the bulk chemistry of the local mineralized or altered rock environment. However, in hydrothermal alteration zones, rutile compositions are clearly anomalous compared to those in unaltered host rocks, and have distinctive elemental associations and substitutions in different types of ore deposits. We have evaluated the mineral chemistry of rutile in >40 ore deposits worldwide. In general, rutile in volcanogenic massive sulfide deposits contains Sn (and locally W, Sb and/or Cu). Rutile from mesothermal and related gold deposits invariably contains W, and in some of the larger and more important deposits, also contains Sb and/or V. Tungsten-bearing detrital rutile grains from the Witwatersrand suggest that paleoplacer mineralization may have had a mesothermal/orogenic gold source. In some magmatic-hydrothermal Pd-Ni-Cu deposits, rutile contains Ni and Cu. Rutile associated with granite-related Sn deposits has strongly elevated concentrations of Sn and W, and granite-pegmatite W-Sn deposits contain rutile with these elements plus Nb and Ta. The Olympic Dam deposit hosts rutile that is enriched in W, Sn and Cu. Rutile associated with porphyry and skarn Cu and Cu-Au deposits tends to contain elevated W, Cu (and sometimes V). Although many ore deposits have well-defined and diagnostic rutile compositions, there are some compositional

  3. Deposited radionuclides

    International Nuclear Information System (INIS)

    The results presented are from the nationwide programme to survey the fall-out levels of radionuclides in Finland. This programme includes results from the vicinities of the nuclear power plants at Loviisa and Olkiluoto. Analysis of deposition samples for their 3H, 89Sr and 90Sr, as well as 137Cs and other gamma radionuclide contents was continued. The results are given as a follow-up to the previous results. The cumulative deposition of long-lived radionuclides retained in soil was measured near the Finnish nuclear power stations. The 90Sr and 137Cs levels in deposition in 1979 were lower than in the previous two years, and no 89Sr was detected. The trend to slightly increasing 3H concentrations of previous years was reversed in 1979. The mean annual deposition of tritium at different sampling stations varied from 85 nCi/m2 (3.1 kBq/m2) to 180 nCi/m2 (6.7 kBq/m2). The total annual deposits of various fission product radionuclides have decreased continuously since the maximum in 1977. No short-lived radionuclides originating from either nuclear explosions or nuclear power plants were observed in 1979. (author)

  4. Deposited radionuclides

    International Nuclear Information System (INIS)

    The measurements presented here were carried out for determination of the fallout levels of radionuclides throughout the country, including the areas surrounding the nuclear power plants at Loviisa and Olkiluoto. The 90Sr, 137Cs and 3H contents of deposition were determined and the results are given as a follow-up to the previous results. 89Sr and other gammaradionuclides in addition to 137Cs were measured from wet and dry deposition. Also 89-90Sr, 239-240Pu, 137Cs and other gammaradionuclides deposited in soil were measured. The radiochemical separation technique was used to determine 89Sr, 90Sr, 137Cs and 239-240Pu. Tritium contents were determined by liquid scintillation counting after electrolytic enrichment. Gammaradionuclides were measured by Ge(Li) spectrometry. In 1977 the contents of the long-lived radionuclides 90Sr and 137Cs in deposition increased to almost the same level as in the early '70s. This is due to the high-yield atmospheric nuclear weapon tests carried out by China. A slight increase in 3H deposition can also be noticed in 1977. The results of soil sample measurements indicate that practically all the activity is found in the top 20 cm layer. (author)

  5. Deposited radionuclides

    International Nuclear Information System (INIS)

    Measurements were carried out to determine the fall-out levels of radionuclides in Finland including those from the surroundings of the nuclear power plants at Loviisa and Olkiluoto. Deposition samples were analysed for their 3H, 89Sr and 90Sr as well as 137Cs and other gamma radionuclide contents. 90Sr, 239,240Pu, as well as 137Cs and other gamma radionuclides deposited in soil were also measured. The 90Sr and 137Cs levels in deposition in 1978 remained at almost the same level as in 1977. The slightly increasing trend in 3H concentrations continued in 1978. The mean annual deposition of tritium at different sampling stations varied from 120 nCi/m2 (4.4 kBq/m2) to 200 nCi/m2 (7.4 kBq/m2). The total annual deposits of various fission product radionuclides during 1978 were smaller than during 1977. No increase in radioactivity originating from nuclear power plants could be observed. (author)

  6. METALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111705 An Junbo(Team 603,Bureau of Nonferrous Metals Geological Exploration of Jilin Province,Hunchun 133300,China);Xu Renjie Geological Features and Ore Genesis of Baishilazi Scheelite Deposit in Yanbian Area(Jilin Geology,ISSN1001-2427,CN22-1099/P,29(3),2010,p.39-43,2 illus.,2 tables,7 refs.)Key words:tungsten ores,Jilin ProvinceThe Baishilazi scheelite deposit is located in contacting zone between the marble of the Late Palaeozoic Qinglongcun Group and the Hercynian biotite granite.The vein and lenticular major ore body is obviously controlled by NE-extending faults and con

  7. Oxygen, carbon and sulphur isotope studies in the Keban Pb-Zn deposits, eastern Turkey: An approach on the origin of hydrothermal fluids

    Science.gov (United States)

    Kalender, Leyla

    2011-03-01

    Pb-Zn deposits are widespread and common in various parts of the Taurus Belt. Most of the deposits are of pyrometasomatic and hydrothermal origin. The Keban Pb-Zn deposits are located along the intrusive contact between the Paleozoic - Lower Triassic Keban Metamorphic Formation and the syenite porphyry of the Upper Cretaceous Keban igneous rocks. Various studies have already been carried out; using fluid inclusion studies on fluorite, calcite and quartz on the pyrite-chalcopyrite bearing Keban ore deposits. This study focuses on the interpretation of stable isotope compositions in connexion with fluid inclusion data. Sulphur isotope values (δ 34S) of pyrite are within the range of -0.59 to +0.17‰ V-CDT ( n = 10). Thus, the source of sulphur is considered to be magmatic, as evidenced by associated igneous rocks and δ 34S values around zero"0". Oxygen isotope values δ 18O of quartz vary between +10.5 and +19.9‰ (SMOW). However, δ 18O and δ 13C values of calcite related to re-crystallized limestone (Keban Metamorphic Formation) reach up to +27.3‰ (SMOW) and +1.6‰ (PDB), respectively. The δ 34S, δ 13C and δ 18O values demonstrate that skarn-type Pb-Zn deposits formed within syeno-monzonitic rocks and calc-schist contacts could have developed at low temperatures, by mixing metamorphic and meteoric waters in the final stages of magmatism.

  8. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131601 Gao Junbo(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550003,China);Yang Ruidong Hydrothermal Venting-Flowing Sedimentation Characteristics of Devonian Barite Deposits from Leji,Zhenning County,Guizhou Province(Acta Sedimentologica Sinica,ISSN1000-0550,CN62-1038/P,30(3),

  9. Mineral potential tracts for polymetallic Pb-Zn-Cu vein deposits (phase V, deliverable 71): Chapter I in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Beaudoin, Georges

    2015-01-01

    In Mauritania, mineral occurrences of the polymetallic Pb-Zn-Cu vein deposit type are found near the Florence-El Khdar shear zone in northeast Mauritania. The deposits visited were deemed representative of other similar occurrences and consist of quartz veins with trace sulfides. The low sulfide and Pb-Zn-Cu content in the quartz veins is unlike producing polymetallic Pb-Zn-Cu vein deposits, such that the veins are not considered to belong to this deposit type. Mineral potential tracts for polymetallic Pb-ZnCu veins are highly speculative considering the lack of known mineralization belonging to this deposit type. Mineral potential tracts for polymetallic Pb-Zn-Cu veins are associated with and surround major shear zones in the Rgueïbat Shield and zones of complex faulting in the southern Mauritanides, at the exclusion of the imbricated thrust faults that are not considered favorable for this deposit type. No skarn and replacement deposits have been documented in Mauritania and the low mineral potential is indicated by lack of causative Mesozoic and Cenozoic mafic to felsic stocks.

  10. Rare Earth Element Geochemistry on Magmatic Rocks and Gold Deposits in Shizishan Ore-Field of Tongling, China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    REE geochemical characteristics of the magmatic rocks and gold deposits in Shizishan ore-field of Tongling were studied. Three types of the magmatic rocks have almost the same chondrite-normalized REE patterns, Eu and Ce anomalous values, and ΣREE, ΣLREE/ΣHREE regular changes, which indicates that their magmas come from the same source and their digenetic mechanism is fractional crystallization. In three gold deposits, the mineral ores and related altered rocks have similar chondrite-normalized REE patterns and sharp Eu positive anomalous values. The REE contents reduced from the magmatic rocks to skarnization or alteration magmatic rocks, skarn type ores, sulphide type ores, wall-rocks limestone or marble. The REE geochemical characteristics of the ores and related rocks show that primary fluids originated from magmatic differentiation in lower pressure of shallow crust, ore-forming hydrothermal solutions gained REE and mineralization elements further from leaching the magmatic rocks, then superimposed and reformed the limestones or marbles and deposited ore-forming material.

  11. Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 69): Chapter H in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Goldfarb, Richard J.; Marsh, Erin; Anderson, Eric D.; Horton, John D.; Finn, Carol A.; Beaudoin, Georges

    2015-01-01

    The gold resources of Mauritania presently include two important deposits and a series of poorly studied prospects. The Tasiast belt of deposits, which came into production in 2007, is located in the southwestern corner of the Rgueïbat Shield and defines a world-class Paleoproterozoic(?) orogenic gold ore system. The producing Guelb Moghrein deposit occurs along a shear zone in Middle Archean rocks at the bend in the Northern Mauritanides and is most commonly stated to be an iron oxide-copper-gold (IOCG) type of deposit, although it also has some important characteristics of orogenic gold and skarn deposits. Both major deposits are surrounded by numerous prospects that show similar mineralization styles. The Guelb Moghrein deposit, and IOCG deposit types in general are discussed in greater detail in a companion report by Fernette (2015). In addition, many small gold prospects, which are probably orogenic gold occurrences and are suggested to be early Paleozoic in age, occur along the length of Southern Mauritanides. Existing data indicate the gold deposits and prospects in Mauritania have a sulfide assemblage most commonly dominated by pyrrhotite and chalcopyrite, and have ore-related fluids with apparently high salinities.

  12. Deposit insurance and international bank deposits

    OpenAIRE

    Harry Huizinga; Gaëtan Nicodème

    2003-01-01

    This paper examines how international depositors respond to national deposit insurance policies. Countries with explicit deposit insurance are found to be relatively attractive to international non-bank depositors. Deposit schemes characterized by co-insurance, a private administration, and a low deposit insurance premium appear to be particularly favored by these depositors. The sensitivity of non-bank deposits to deposit insurance policies opens up the possibility of international regulator...

  13. Geochronology and geochemistry constraints of the Early Cretaceous Taibudai porphyry Cu deposit, northeast China, and its tectonic significance

    Science.gov (United States)

    Zhou, Zhen-Hua; Mao, Jing-Wen; Wu, Xin-Li; Ouyang, Hen-Gen

    2015-05-01

    The southern Great Xing'an Range (SGXR), located in the southeastern part of Inner Mongolia, China, shows intense Mesozoic tectono-magmatic activity and hosts economically important polymetallic (Cu-Pb-Zn-Sn-Fe-Ag-Au-Mo) mineralization. Here, we present new zircon U-Pb ages, whole-rock geochemical data, Nd-Sr-Hf isotopic data and Re-Os ages for the Taibudai deposit in the SGXR. The Taibudai granitoids show high SiO2 (70.62-72.13 wt.%) and alkali (Na2O + K2O = 7.04-8.60 wt.%) concentrations, low MgO (0.89-1.37 wt.%) and Al2O3 (∼14 wt.%), ASI ratios geology, tectonic evolution, and age data from the literature, suggests that the Early Cretaceous (∼140 Ma) was the peak metallogenic epoch for the Great Xing'an Range, and the mineralization in this period generally takes the form of porphyry, skarn, or hydrothermal polymetallic ore deposits in an active extensional continental margin environment. The Taibudai porphyry and associated mineralization provides a typical example of magmatism and metallogeny associated with a Paleo-Pacific plate subduction, continental margin, back-arc extensional setting.

  14. Multi-episode fluid boiling in the Shizishan copper-gold deposit at Tongling, Anhui Province: its bearing on oreformation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Shizishan copper-gold deposit at Tongling, Anhui Province consists of two magmato-hydrothermal mineralization types: the crypto-explosive breccia type and the skarn type. At least four episodes of boiling occurred to the ore-forming fluids in this deposit. The first episode took place in accompany with the formation of the crypto-explosive breccias. The melt-fluid inclusions giving temperatures above 600℃ and salinities higher than 42% NaCl equiv represent a residual magma related to this episode. The second episode occurred during skarnization, giving fluid temperatures of 422℃-472℃, averaging 458℃, and salinities of 10.2%-45.1% NaCl equiv. The third episode corresponds to the main mineralization stage, i.e., the quartz-sulphide stage. Fluid temperatures of this episode vary in a range of 337℃-439℃ with an average of 390℃, and salinities in a range of 3%-30% NaCl equiv. The forth episode happened at the waning stage of mineralization, giving fluid temperatures below 350℃ with an average of 265℃ and salinities of 2.1%-40.4% NaCl equiv.

  15. NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111761 Chen Hua(115 Geological Party,Guizhou Bureau of Geology and Mineral Exploration & Development,Guiyang 551400,China);Deng Chao Analysis on the Metallogenic Environment of Maochang Bauxite in Guizhou Province(Guizhou Geology,ISSN1000-5943,CN52-1059/P,27(3),2010,p.198-201,2 illus.,1 table,8 refs.)Key words:bauxite deposit,Guizhou Province By long time physical and chemical process,the carbonate rock after Central Guizhou uplidft,becomes red clay,after further weathering,the red clay decomposed into the oxide,hydroxide of Al and Fe,in the dissolution hole and depression,it concentrates primary fragmentary tight and earthy karst bauxite ore.Because the variation of landform,it decomposes and cracks again,affords the material source

  16. Abundances of platinum group elements in native sulfur condensates from the Niuatahi-Motutahi submarine volcano, Tonga rear arc: Implications for PGE mineralization in porphyry deposits

    Science.gov (United States)

    Park, Jung-Woo; Campbell, Ian H.; Kim, Jonguk

    2016-02-01

    Some porphyry Cu-Au deposits, which are enriched in Pd, are potentially an economic source of Pd. Magmatic volatile phases are thought to transport the platinum group elements (PGEs) from the porphyry source magma to the point of deposition. However, the compatibilities of the PGEs in magmatic volatile phases are poorly constrained. We report PGE and Re contents in native sulfur condensates and associated altered dacites from the Niuatahi-Motutahi submarine volcano, Tonga rear arc, in order to determine the compatibility of PGEs and Re in magmatic volatile phases, and their mobility during secondary hydrothermal alteration. The native sulfur we analyzed is the condensate of a magmatic volatile phase exsolved from the Niuatahi-Motutahi magma. The PGEs are moderately enriched in the sulfur condensates in comparison to the associated fresh dacite, with enrichment factors of 11-285, whereas Au, Cu and Re are strongly enriched with enrichment factors of ∼20,000, ∼5000 and ∼800 respectively. Although the PGEs are moderately compatible into magmatic volatile phases, their compatibility is significantly lower than that of Au, Cu and Re. Furthermore, the compatibility of PGEs decrease in the order: Ru > Pt > Ir > Pd. This trend is also observed in condensates and sublimates from other localities. PGE mineralization in porphyry Cu-Au deposits is characterized by substantially higher Pd/Pt (∼7-60) and Pd/Ir (∼100-10,500) than typical orthomagmatic sulfide deposits (e.g. Pd/Pt ∼0.6 and Pd/Ir ∼20 for the Bushveld). It has previously been suggested that the high mobility of Pd, relative to the other PGEs, may account for the preferential enrichment of Pd in porphyry Cu-Au deposits. However, the low compatibility of Pd in the volatile phase relative to the other PGEs, shown in this study, invalidates this explanation. We suggest that the PGE geochemistry of Pd-rich Cu-Au deposits is principally derived from the PGE characteristics of the magma from which the ore

  17. Transverse Momentum Spectra of KS0 and K*0 at Midrapidity in d + Au, Cu + Cu, and p+p Collisions at sNN=200  GeV

    OpenAIRE

    Bao-Chun Li; Guo-Xing Zhang; Yuan-Yuan Guo

    2015-01-01

    We analyze transverse momentum spectra of KS0 and K*0 at midrapidity in d + Au, Cu + Cu, and p+p collisions at sNN=200  GeV in the formworks of Tsallis statistics and Boltzmann statistics, respectively. Both of them can describe the transverse momentum spectra and extract the thermodynamics parameters of matter evolution in the collisions. The parameters are helpful for us to understand the thermodynamics factors of the particle production.

  18. 安徽池州铜山铜矿床元素地球化学分带特征及意义%Element geochemistry zoning of Tongshan copper deposit in Chizhou, Anhui Province, and its implications

    Institute of Scientific and Technical Information of China (English)

    张智宇; 杜杨松; 庞振山; 张静; 滕传耀

    2012-01-01

    The Tongshan copper deposit is a medium-sized skam deposit, which is located in the Anqing-Guichi ore concentration area along the Middle and Lower Yangtze River metallogenic belt. Ore bodies occur in the contact zone between the Tongshan intrusion and carbonate of the Qixia Formation of the Lower Permian series. Element analyses of the samples systematically collected along a typical section show zoning with gradual variation in elements from magmatic rocks through skams to carbonates. Skarns near the intrusion are rich in Si, Fe, Mg, siderophile element Co, chalcophile elements Cu and Ag, while those far from the intrusion are rich in Ca, Mn, Al, Ti, REE, chalcophile elements Pb and Zn. Strongly silicated rock far from the marble zone is enriched in Si, Fe, Li and Co, but strongly depleted in Ca, Sr and REE. This zoning may be explained based on the element remobilization theory. During the formation of skarns, Si, Fe, Mg, Al, Li, REE, LJLEs (e.g., Rb and Cs) , siderophile elements (Co and V), chalcophile element Zn, and HFSEs (e.g., Ta, Zr, Nb, Hf, Ga and Be) carried by magmatic-hydrothermal fluids might be transferred into the marble and enriched in skarns, while Ca in the marble activated and enriched in skarns, with moving out of Sr, K and Pb. Weakly altered and mineralized skam is enriched in REE( XREE = 122. 0 × 10 -6 ) , especially LREE [ ( La/Sm) N = 3. 99 ] , but depleted in HREE [ (Gd/Yb) N = 2. 85 ] , with a negative Eu anormaly ( δEu = 0. 69). Chondrite-normalized HREE pattern of skarn is similar to that of fresh quartz-monzonite-porphyry, but it is relative low in LREE ( e. g., La, Ce). The variation of elements along the section and REE pattern of skarns indicate a contact metasomatic origin of the Tongshan skam copper deposit. The data mentioned above combined with H-0 isotopic analyses indicate the derivation of ore-forming fluids is mainly from magmatic hydrothermal solution, with addition of meteoric water into the fluids at the stage of

  19. Metamorphic Rock-Hosted Orogenic Gold Deposit Type as a Source of Langkowala Placer Gold, Bombana, Southeast Sulawesi

    Directory of Open Access Journals (Sweden)

    Arifudin Idrus

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v6i1.114In 2008, placer gold was discovered in Langkowala area (Bombana Regency, Southeast Sulawesi, Indonesia, and more than 60,000 traditional gold miners in the early 2009 have been operating by digging vertical pits and panning active stream sediments. The grade of placer gold ranges from 50 to 140 g/t. Local geological framework indicates that the placer gold is not related to volcanic rock-related hydrothermal gold deposit, e.g. epithermal, skarn or porphyry. This paper describes a preliminary study on possible primary deposit type as a source of the Langkowala (Bombana secondary placer gold. A field study indicates that the Langkowala (Bombana placer/paleoplacer gold is possibly related to gold-bearing quartz veins/veinlets hosted by metamorphic rocks particularly mica schist and metasediments in the area. These quartz veins/veinlets are currently recognized in metamorphic rocks at Wumbubangka Mountains, a northern flank of Rumbia Mountain Range. Sheared, segmented quartz veins/veinlets are of 2 cm to 2 m in width and contain gold in a grade varying between 2 and 61 g/t. At least, there are two generations of the quartz veins. The first generation of quartz vein is parallel to foliation of mica schist and metasediments with general orientation of N 300oE/60o; the second quartz vein generation crosscut the first quartz vein and the foliation of the wallrock. The first quartz veins are mostly sheared/deformed, brecciated, and occasionally sigmoidal, whereas the second quartz veins are relatively massive. The similar quartz veins/veinlets types are also probably present in Mendoke Mountain Range, in the northern side of Langkowala area. This primary gold deposit is called as ‘orogenic gold type’. The orogenic gold deposit could be a new target of gold exploration in Indonesia in the future.

  20. Environment of ore deposition in the Creede mining district, San Juan Mountains, Colorado: Part VI. Maximum duration for mineralization of the OH vein

    Science.gov (United States)

    Campbell, W.R.; Barton, P.B.

    2005-01-01

    The rate at which ore deposits form is one of the least well established parameters in all of economic geology. However, increased detail in sampling, improved technology of dating, and sophistication in modeling are reducing the uncertainties and establishing that ore formation, at least for the porphyry copper-skarn-epithermal base and precious metals deposit package, may take place in surprisingly brief intervals. This contribution applies another approach to examine the duration of mineralization. The degree to which compositional gradients within single crystals has flattened through solid-state diffusion offers a measure of the thermal dose (that is temperature combined with time) that the crystals have been subjected to since deposition. Here we examine the steepness of gradients in iron content within individual single sphalerite crystals from the epithermal silver-lead-zinc deposit in the OH vein at Creede, Colorado. Two initial textures are considered: growth-banded crystals and compositionally contrasting overgrowths that succeed crosscutting dissolution or fractured surfaces. The model used estimates the maximum possible time by assuming a perfectly sharp original compositional step, and it asks how long it would take at a known temperature for the gradient measured today to have formed. Applying the experimentally determined diffusion rates of Mizuta (1988a) to compositional gradients (ranging from 0.4-2.2 mol % FeS/??m) measured by the electron microprobe in 2-??m steps on banded sphalerite formed early in the paragenetic history yields a maximum duration of less than ???10,000 yr. Sphalerite from a solution unconformity in a position midway through the paragenetic sequence is indistinguishable from instantaneous deposition, supporting the conclusion of rapid ore formation. While this formation interval seems very brief, it is consistent with less well constrained estimates using entirely different criteria. ?? 2005 Society of Economic Geologists, Inc.

  1. Re-Os isotope evidence for mixed source components in carbonate-replacement Pb-Zn-Ag deposits in the Lavrion district, Attica, Greece

    Science.gov (United States)

    Spry, Paul G.; Mathur, Ryan D.; Bonsall, Todd A.; Voudouris, Panagiotis Ch.; Melfos, Vasilios

    2014-08-01

    The Lavrion ore district contains carbonate-replacement and vein-type Pb-Zn-Ag deposits as well as low-grade porphyry Mo, Cu-Fe skarn, and minor breccia-hosted Pb-Zn-Cu sulfide mineralization. These ore types are spatially related to a Late Miocene granodiorite intrusion (7 to 10 Ma), and various sills and dikes of mafic to felsic composition. Samples of sphalerite and pyrite from the Ilarion carbonate replacement deposit, and galena from Vein 80 (vein-type mineralization) in the Adami deposit show heterogeneous Re-Os values. These values were partially disturbed by hydrothermal activity associated with the formation of hydrothermal veins (e.g., Vein 80). A plot of initial 187Os/188Os versus 1/Oscommon ratios for pyrite and sphalerite from the Ilarion deposit form a mixing line (r2 = 0.78) between high concentration crustal-like and low concentration mantle-like end-members, or two crustal end-members one of which was more radiogenic than the other. Based on the Re-Os systematics and previously published geological and geochemical evidence, the most plausible explanation for the Re-Os isotope data is that ore-forming components were derived from mixed sources, one of which was a radiogenic crustal source from schists and carbonates probably near intrusion centers and the other, intrusive rocks in the district that are less radiogenic. Although the Re and Os concentrations of galena from Vein 80 are above background values they cannot be used as a chronometer. However, the results of the current study suggest that although pyrite, sphalerite, and galena are poor geochronometers in this ore deposit, due to partial open-system behavior, they still yield valuable information on the origin of the source rocks in the formation of bedded replacement and vein mineralization in the Lavrion district.

  2. Derivation of S and Pb in phanerozoic intrusion-related metal deposits from neoproterozoic sedimentary pyrite, Great Basin, United States

    Science.gov (United States)

    Vikre, P.G.; Poulson, S.R.; Koenig, A.E.

    2011-01-01

    The thick (???8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high d34S values (-11.6 to 40.8%, Pb isotopes ( 207Pb/204Pb Pb-Zn-Cu-Ag-Au deposits associated with Jurassic, Cretaceous, and Tertiary granitic intrusions (intrusion-related metal deposits) contain galena and other sulfide minerals with S and Pb isotope compositions similar to those of TDS sedimentary pyrite, consistent with derivation of deposit S and Pb from TDS pyrite. Minor element abundances in TDS pyrite (e.g., Pb, Zn, Cu, Ag, and Au) compared to sedimentary and hydrothermal pyrite elsewhere are not noticeably elevated, implying that enrichment in source minerals is not a precondition for intrusion-related metal deposits. Three mechanisms for transferring components of TDS sedimentary pyrite to intrusion-related metal deposits are qualitatively evaluated. One mechanism involves (1) decomposition of TDS pyrite in thermal aureoles of intruding magmas, and (2) aqueous transport and precipitation in thermal or fluid mixing gradients of isotopically heavy S, radiogenic Pb, and possibly other sedimentary pyrite and detrital mineral components, as sulfide minerals in intrusion-related metal deposits. A second mechanism invokes mixing and S isotope exchange in thermal aureoles of Pb and S exsolved from magma and derived from decomposition of sedimentary pyrite. A third mechanism entails melting of TDS strata or assimilation of TDS strata by crustal or mantle magmas. TDS-derived or assimilated magmas ascend, decompress, and exsolve a mixture of TDS volatiles, including isotopically heavy S and radiogenic Pb from sedimentary pyrite, and volatiles acquired from deeper crustal or mantle sources. In the central and eastern Great Basin, the wide distribution and high density of small to mid-sized vein, replacement, and skarn intrusion-related metal deposits

  3. 3D modelling and sheath folding at the Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit and implications for exploration in a 1.9 Ga ore district, Fennoscandian Shield, Sweden

    Science.gov (United States)

    Kampmann, Tobias C.; Stephens, Michael B.; Weihed, Pär

    2016-06-01

    Altered and mineralized rocks at the Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit, situated in the Palaeoproterozoic Bergslagen ore district in the south-western part of the Fennoscandian Shield, have been metamorphosed at low-pressure, amphibolite-facies conditions and affected by ductile deformation. Using combined surface mapping of lithology and structure, drill core logging and microstructural work, the polyphase (D1 and D2) ductile deformation is demonstrated and a 3D model for the deposit created. Mineral associations include quartz, biotite, cordierite, anthophyllite, and minor almandine, andalusite and chlorite in silicate-rich altered rock, calcite or dolomite in marble and tremolite-actinolite or diopside-hedenbergite in skarn. The silicate minerals show varying growth patterns during the different phases of the tectonothermal evolution, with considerable static grain growth occurring between D1 and D2, and even after D2. F2 sheath folding along axes that plunge steeply to the SSE, parallel to a mineral stretching lineation and the dip direction of the S2 foliation, is suggested as a key deformation mechanism forming steeply plunging, cone- to rod-shaped mineralized bodies. This contrasts with a previous structural model invoking fold interference. A major shear zone with talc-chlorite-(quartz-biotite) mineral association separates the northern and southern structural domains at the deposit and bounds the polymetallic massive sulphides to the north.

  4. 3D modelling and sheath folding at the Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit and implications for exploration in a 1.9 Ga ore district, Fennoscandian Shield, Sweden

    Science.gov (United States)

    Kampmann, Tobias C.; Stephens, Michael B.; Weihed, Pär

    2016-01-01

    Altered and mineralized rocks at the Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit, situated in the Palaeoproterozoic Bergslagen ore district in the south-western part of the Fennoscandian Shield, have been metamorphosed at low-pressure, amphibolite-facies conditions and affected by ductile deformation. Using combined surface mapping of lithology and structure, drill core logging and microstructural work, the polyphase (D1 and D2) ductile deformation is demonstrated and a 3D model for the deposit created. Mineral associations include quartz, biotite, cordierite, anthophyllite, and minor almandine, andalusite and chlorite in silicate-rich altered rock, calcite or dolomite in marble and tremolite-actinolite or diopside-hedenbergite in skarn. The silicate minerals show varying growth patterns during the different phases of the tectonothermal evolution, with considerable static grain growth occurring between D1 and D2, and even after D2. F2 sheath folding along axes that plunge steeply to the SSE, parallel to a mineral stretching lineation and the dip direction of the S2 foliation, is suggested as a key deformation mechanism forming steeply plunging, cone- to rod-shaped mineralized bodies. This contrasts with a previous structural model invoking fold interference. A major shear zone with talc-chlorite-(quartz-biotite) mineral association separates the northern and southern structural domains at the deposit and bounds the polymetallic massive sulphides to the north.

  5. Re-Os age of molybdenite from the Baoshan copper polymetallic deposit in the Jiurui ore concentration area along the middle-lower Yangtze River region and its geological significance%长江中下游九瑞矿集区宝山铜多金属矿床辉钼矿Re-Os年龄及其地质意义

    Institute of Scientific and Technical Information of China (English)

    胡正华; 聂龙敏; 雷天浩; 胡文洁; 张芳荣; 吴施金; 沙珉; 龚良信; 谢瑞丰; 文亮先; 王先广; 李永明; 刘善宝; 张家菁; 陈毓川; 曾庆权; 王艺云; 蒋金明

    2015-01-01

    九瑞地区斑岩-矽卡岩型矿床是长江中下游地区Cu-Au-Mo(Fe)多金属成矿带的重要组成部分,宝山铜多金属矿床是江西省实施找矿突破战略以来,在九瑞矿集区界首—大桥背斜核部新发现的首个中型以上斑岩-矽卡岩型铜多金属矿床。本文利用辉钼矿Re-Os同位素定年方法对宝山矿床进行了成矿时代的研究,获得了6件辉钼矿Re-Os同位素模式年龄为(147.2±3.6) Ma~(150.5±2.7) Ma,加权平均年龄为(148±1) Ma, MSWD=1.03。6件样品其等时线年龄为(148.6±2.6) Ma, MSWD=1.9,代表了宝山矿床的成矿时代,与九瑞矿集区其他斑岩-矽卡岩型铜多金属矿床(武山、城门山、湖北丰山洞、鸡笼山、宋家冲、邓家山、通江岭)以及长江中下游地区鄂东南、铜陵矿集区斑岩-矽卡岩铜多金属矿床的形成时代高度一致,它们均为中国东部EW特堤斯构造域向NE古太平洋构造域大转折背景下,软流圈上涌和玄武质岩浆底侵而导致壳幔同熔所引起的燕山期花岗质岩浆岩活动的产物。%Porphyry-skarn deposits in Jiurui area constitute an important part of the middle-lower Yangtze River Cu-Au-Mo (Fe) polymetallic ore belt. Since the implementation of the prospecting breakthrough strategy, the Baoshan deposit has been the first medium-size porphyry-skarn copper polymetallic deposit discovered at the core of Jieshou-Daqiao anticline in Jiurui area. In this paper, molybdenite Re-Os dating was used to study the mineralization time of the Baoshan deposit and, as a result, six molybdenite Re-Os model ages of 147.2±3.6 Ma to 150.5±2.7 Ma and weighted average age of 148±1 Ma (MSWD=1.03) were obtained. These six molybdenite Re-Os model ages yielded an isochron age of 148.6±2.6 Ma (MSWD=1.9), which represents the ore-forming age of the Banshan deposit. The ore-forming age of the Baoshan deposit is similar to ages of other porphyry-skarn type copper polymetallic deposits in Jiurui area (e

  6. Electro-Deposition Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The electro-deposition laboratory can electro-deposit various coatings onto small test samples and bench level prototypes. This facility provides the foundation for...

  7. Calcium Pyrophosphate Deposition (CPPD)

    Science.gov (United States)

    ... Patient / Caregiver Diseases & Conditions Calcium Pyrophosphate Deposition (CPPD) Calcium Pyrophosphate Deposition (CPPD) Fast Facts The risk of ... young people, too. Proper diagnosis depends on detecting calcium pyrophosphate crystals in the fluid of an affected ...

  8. Selection of bentonite deposits

    International Nuclear Information System (INIS)

    The selection of bentonite deposits is to offer a supply base of backfill/buffer materials for high-level radioactive waste repository in China. In this paper the comprehensive evaluation criteria were discussed first, then a comprehensive comment on bentonite deposits in China was given. The properties of geographic distribution, origin, reserves and ore quality of bentonite deposits were also discussed. The comprehensive comparison studies on 12 large-sized bentonite deposits was presented. Based on the results obtained Gaomiaozi bentonite deposit, Inner Mongolia, was recommended as the first choice of backfill/buffer materials for repository in China. (author)

  9. 广东省阳山县石寨铅锌多金属矿地质特征%Geological characteristics of Shizhai Pb-Zn polymetallic deposit in Yangshan of Guangdong

    Institute of Scientific and Technical Information of China (English)

    冼源宏; 郭华; 占达积; 王灿松

    2016-01-01

    阳山县石寨矿区隶属南岭钨锡多金属成矿带,属矽卡岩型铅锌多金属矿,是武警黄金九支队首次针对此类型矿床进行勘查。矿区内花岗岩体广泛与石炭系地层接触,接触带长度延伸较长,具有较好的成矿条件。已发现的矽卡岩带,受接触带构造影响,在走向与倾向上整体呈“S”型舒缓波状,铅锌矿体主要赋存于矽卡岩带中。通过物化探基础性工作,并利用钻探及槽探工程进行查证,物化探异常与已发现矿脉吻合度较高,且深部呈现铅锌多金属元素富集增高的趋势,显示了较好的找矿前景。通过对区内多金属矿床地质特征、成矿规律分析与找矿前景分析总结,为在该区深部进一步开展找矿勘探,扩大其远景规模提供了明确方向和详实的地质资料。%Shizhai mining area of Yangshan is a skarn-type Pb-Zn polymetallic deposit which is located in Nan-ling W-Sn polymetallic metallogenic belt.It’s the first time that No.9 Gold Geological Team of CAPF has conducted exploration works on this type of deposits.The metallogenic conditions are favorable because the contact between granite body and Carboniferous stratum is extensive and long in length in this mining area. Under the influence of the structure of contact zone,the discovered skarn belt shows S-shaped gentle wave-forms in strike and trend.The Pb-Zn orebodies mainly occur in the skarn belt.Through geophysical and geo-chemical exploration as well as drilling and trenching works ,it is verified that the geophysical and geoche-mical anomalies match very well with the discovered ore veins,and elements like Pb and Zn are enriched and increased in the deeper part.It is indicated that the mining area has great prospecting potential.This paper analyzed and summarized the geological characteristics,metallogenic regularity and prospecting potential of the poly-metallic deposits in the area,and provided a clear direction

  10. Acid Deposition Phenomena

    International Nuclear Information System (INIS)

    Acid deposition, commonly known as acid rain, occurs when emissions from the combustion of fossil fuels and other industrial processes undergo complex chemical reactions in the atmosphere and fall to the earth as wet deposition (rain, snow, cloud, fog) or dry deposition (dry particles, gas). Rain and snow are already naturally acidic, but are only considered problematic when less than a ph of 5.0 The main chemical precursors leading to acidic conditions are atmospheric concentrations of sulfur dioxide (SO2) and nitrogen oxides (NOx). When these two compounds react with water, oxygen, and sunlight in the atmosphere, the result is sulfuric (H2SO4) and nitric acids (HNO3), the primary agents of acid deposition which mainly produced from the combustion of fossil fuel and from petroleum refinery. Airborne chemicals can travel long distances from their sources and can therefore affect ecosystems over broad regional scales and in locations far from the sources of emissions. According to the concern of petroleum ministry with the environment and occupational health, in this paper we will discussed the acid deposition phenomena through the following: Types of acidic deposition and its components in the atmosphere Natural and man-made sources of compounds causing the acidic deposition. Chemical reactions causing the acidic deposition phenomenon in the atmosphere. Factors affecting level of acidic deposition in the atmosphere. Impact of acid deposition. Procedures for acidic deposition control in petroleum industry

  11. HT deposition to snow

    International Nuclear Information System (INIS)

    A series of exposure chamber measurements of the deposition of HT to snow were conducted at a field site. These experiments indicate that deposition velocities for conversion of HT to HTO are likely 10-6 m s-1 or less, which is approximately two to three orders of magnitude slower than deposition to soils under growing season conditions. Previous measurements of deposition to soil under freezing or near-freezing conditions also indicated very low deposition velocities. Deposition under winder conditions is thus likely to be much slower than deposition to soil under growing season conditions. It is concluded that exposure to HTO formed by the conversion of HT to HTO during a winter release of HT over snow or frozen ground is likely to be small compared to the dose from the HT plume itself. (4 tabs., 5 figs., 14 refs.)

  12. Airfoil deposition model

    Science.gov (United States)

    Kohl, F. J.

    1982-01-01

    The methodology to predict deposit evolution (deposition rate and subsequent flow of liquid deposits) as a function of fuel and air impurity content and relevant aerodynamic parameters for turbine airfoils is developed in this research. The spectrum of deposition conditions encountered in gas turbine operations includes the mechanisms of vapor deposition, small particle deposition with thermophoresis, and larger particle deposition with inertial effects. The focus is on using a simplified version of the comprehensive multicomponent vapor diffusion formalism to make deposition predictions for: (1) simple geometry collectors; and (2) gas turbine blade shapes, including both developing laminar and turbulent boundary layers. For the gas turbine blade the insights developed in previous programs are being combined with heat and mass transfer coefficient calculations using the STAN 5 boundary layer code to predict vapor deposition rates and corresponding liquid layer thicknesses on turbine blades. A computer program is being written which utilizes the local values of the calculated deposition rate and skin friction to calculate the increment in liquid condensate layer growth along a collector surface.

  13. Synthesis and characterization in AuCu–Si nanostructures

    International Nuclear Information System (INIS)

    Au/Cu bilayers with different Au:Cu concentrations (25:75, 50:50 and 75:25 at.%) were deposited on Si(100) substrates by thermal evaporation. The thicknesses of all Au/Cu bilayers were 150 nm. The alloys were prepared by thermal diffusion into a vacuum oven with argon atmosphere at 690 K during 1 h. X-ray diffraction analysis revealed different phases of AuCu and CuSi alloys in the samples after annealing process. CuSi alloys were mainly obtained for 25:75 at.% samples, meanwhile the AuCuII phase dominates for samples prepared with 50:50 at.%. Additionally, the Au:Cu alloys with 75:25 at.%, produce Au2Cu3 and Au3Cu phases. The formed alloys were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) to study the morphology and the elemental concentration of the formed alloys. - Highlights: • AuCu/Si alloy thin films were prepared by thermal diffusion. • Alloys prepared with 50 at.% of Au produce the AuCuII phase. • Alloys prepared with 75 at.% of Au produce Au3Cu and Au2Cu3 phases. • All alloys present diffusion of Si and Cu through the CuSi alloy formation

  14. Synthesis and characterization in AuCu–Si nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Novelo, T.E., E-mail: tenovelo@hotmail.com [Centro de Investigación en Materiales Avanzados, S.C., Laboratorio Nacional de Nanotecnología, Av. Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31109 Chihuahua, Chihuahua Mexico (Mexico); Amézaga-Madrid, P. [Centro de Investigación en Materiales Avanzados, S.C., Laboratorio Nacional de Nanotecnología, Av. Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31109 Chihuahua, Chihuahua Mexico (Mexico); Maldonado, R.D. [Universidad Anáhuac-Mayab, Carretera Mérida-Progreso Km. 15.5 A.P. 96-Cordemex, CP. 97310 Mérida, Yucatán Mexico (Mexico); Oliva, A.I. [Centro de Investigación y de Estudios Avanzados el IPN Unidad Mérida, Departamento de Física Aplicada, Km 6 Antigua Carretera a Progreso, A.P. 73-Cordemex, 97310 Mérida, Yucatán Mexico (Mexico); Alonzo-Medina, G.M. [Universidad Anáhuac-Mayab, Carretera Mérida-Progreso Km. 15.5 A.P. 96-Cordemex, CP. 97310 Mérida, Yucatán Mexico (Mexico)

    2015-03-15

    Au/Cu bilayers with different Au:Cu concentrations (25:75, 50:50 and 75:25 at.%) were deposited on Si(100) substrates by thermal evaporation. The thicknesses of all Au/Cu bilayers were 150 nm. The alloys were prepared by thermal diffusion into a vacuum oven with argon atmosphere at 690 K during 1 h. X-ray diffraction analysis revealed different phases of AuCu and CuSi alloys in the samples after annealing process. CuSi alloys were mainly obtained for 25:75 at.% samples, meanwhile the AuCuII phase dominates for samples prepared with 50:50 at.%. Additionally, the Au:Cu alloys with 75:25 at.%, produce Au{sub 2}Cu{sub 3} and Au{sub 3}Cu phases. The formed alloys were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) to study the morphology and the elemental concentration of the formed alloys. - Highlights: • AuCu/Si alloy thin films were prepared by thermal diffusion. • Alloys prepared with 50 at.% of Au produce the AuCuII phase. • Alloys prepared with 75 at.% of Au produce Au{sub 3}Cu and Au{sub 2}Cu{sub 3} phases. • All alloys present diffusion of Si and Cu through the CuSi alloy formation.

  15. Palaeoproterozoic metavolcanic and metasedimentary succession hosting the Dannemora iron ore deposits, Bergslagen region, Sweden

    Science.gov (United States)

    Dahlin, P.

    2012-04-01

    The Dannemora inlier constitutes some of the best preserved primary structures and textures in the metavolcanic and metasedimentary rocks in the Bergslagen region. The aim for this study was to define and interpret the primary textures and deposition environment to obtain a better understanding of the palaeoenvironment in which the Dannemora iron ore deposit formed. In addition, the region has been subjected to at least two fold episodes therefore the establishment of stratigraphy and younging directions were crucial for structural interpretations. The Bergslagen region, located in the south-central Sweden, represents a back-arc setting active c. 1.9 Ga and consisted of numerous large calderas, that accommodated pyroclastic deposits of great thicknesses. The Dannemora inlier is composed of the supracrustal the Dannemora Formation, which is dominated by of metavolcanic rocks and subordinated by marble. The succession is 700-800 m and is divided into a lower and an upper member. The latter hosts the second largest iron ore deposit in the Bergslagen region. The ore is hosted by manganiferous skarn and dolomitic carbonate (marble) and is situated within uppermost part of the upper member positioned in an isoclinal syncline. From reflection seismic imaging and 3-D processing, the ore has been interpreted to reach depths of c. 2000 m. The presence of an anticline west of the ore bearing syncline is suggested by the geochemical similarities of rock units. Undisturbed layers of ash-siltstone with normal grading and fluid-escape structures, units of pyroclastic density currents and ash-fall in the eastern part of the Dannemora inlier indicate subaqueous deposition below wave base of the upper member. Reworking of the volcaniclastic deposits is evident in e.g. channels and cross-bedding, on the other hand, implies deposition above wave base of the upper member in the central part of Dannemora inlier. The thickness of the marble in the eastern part is c. 80 m and in the

  16. Local structure of disordered Au-Cu and Au-Ag alloys

    International Nuclear Information System (INIS)

    X-ray-absorption fine structure (XAFS) and x-ray-diffraction (XRD) measurements of disordered alloys AuxCu1-x and Au0.5Ag0.5 prepared by melt spinning were performed. In the Au0.5Ag0.5 alloy, no significant local deviations of the atoms from the average fcc lattice were detected while in AuxCu1-x alloys, significant deviations of atoms from the average fcc lattice were found. Mean-square vibrations of the Cu-Cu distances revealed by the XAFS in AuxCu1-x alloys indicate the weakening of contact between Cu atoms in the dilute limit. Our computer simulation for AuxCu1-x clusters of 105 atoms reproduces the main features of both the XAFS and XRD data

  17. Shedding of ash deposits

    DEFF Research Database (Denmark)

    Zbogar, Ana; Frandsen, Flemming; Jensen, Peter Arendt;

    2009-01-01

    Ash deposits formed during fuel thermal conversion and located on furnace walls and on convective pass tubes, may seriously inhibit the transfer of heat to the working fluid and hence reduce the overall process efficiency. Combustion of biomass causes formation of large quantities of troublesome...... ash deposits which contain significant concentrations of alkali, and earth-alkali metals. The specific composition of biomass deposits give different characteristics as compared to coal ash deposits, i.e. different physical significance of the deposition mechanisms, lower melting temperatures, etc....... Low melting temperatures make straw ashes especially troublesome, since their stickiness is higher at lower temperatures, compared to coal ashes. Increased stickiness will eventually lead to a higher collection efficiency of incoming ash particles, meaning that the deposit may grow even faster...

  18. The Imouraren deposit, Niger

    International Nuclear Information System (INIS)

    Imouraren deposit has been discovered in the late sixties. It is located South of Arlit where two mines are mined, one open pit and one underground. The grades of reduced Imouraren Uranium ore are lesser than these of Arlit and Akouta. Imouraren deposit is owned by COGEMA (France): 70% and ONAREM (Niger): 30%. The concession area is about 45 square kilometers. The thickness of the deposit is between 50 and 60 meters and its depth reaches 110 to 170 meters. (author)

  19. Deposits and relationship lending

    OpenAIRE

    Mitchell Berlin; Mester, Loretta J.

    1998-01-01

    The authors empirically examine the hypothesis that access to deposits with inelastic rates (core deposits) permits a bank to make contractual agreements with borrowers that are infeasible if the bank must pay market rates for its funds. Access to core deposits insulates a bank's costs of funds from exogenous shocks, allowing the bank to insulate its borrowers against exogenous credit shocks. Using a large sample of loans from the Survey of the Terms of Bank Lending, the authors find that whe...

  20. Uraniferous surficial deposits

    International Nuclear Information System (INIS)

    As a result of the discovery of uranium in surficial deposits of Tertiary to Recent age, in Australia and Southern Africa, increasing attention is being paid to the location and understanding of the genesis of these deposits. The paper discusses the definitions and terminology currently in use and a classification of these deposits is presented. It is concluded that in order to obtain a measure of clarity, the terms calcrete, gypcrete and dolocrete should not be used to describe the uraniferous valley-fill deposits of Southern Africa and Australia

  1. Deposition patterns with Turbuhaler.

    Science.gov (United States)

    Borgström, L

    1994-01-01

    The degree of lung deposition is an important factor in the evaluation of different inhalation flow driven dry powder inhalers. A number of studies using radioactive and non-radioactive methods have been performed with Turbuhaler to assess lung deposition under different conditions. Mean total lung deposition of terbutaline sulfate or budesonide via Turbuhaler in healthy volunteers ranged from 21-32% of the dose when a normal inhalation flow (60L/min) was used. At a low flow (30L/min) a mean 15% of the dose was deposited in the lungs, a similar value as for a well-performed inhalation via a pressurized metered dose inhaler. Regional deposition of inhaled drug can be expressed as the ratio between the amount of drug deposited in the more peripheral parts of the lung relative to the more central parts. In a comparative study, budesonide and terbutaline sulfate were given by inhalation via Turbuhaler to healthy volunteers. The ratio of peripheral to central deposition was 2.03 for terbutaline and 1.72 for budesonide. Thus, both the water-soluble terbutaline sulfate and the non-water soluble budesonide seemed to behave in the same way when inhaled via Turbuhaler. In conclusion, Turbuhaler delivers over 20% of a metered dose to the lungs when inhaled at a normal inhalation flow rate. The regional deposition pattern in the lungs was the same for terbutaline sulfate and budesonide, in spite of differences in water solubility. PMID:10147081

  2. MAPLE deposition of nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Caricato, A.P., E-mail: annapaola.caricato@le.infn.it [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Arima, V.; Catalano, M. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Cesaria, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Cozzoli, P.D. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Martino, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Taurino, A.; Rella, R. [Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, I-73100 Lecce (Italy); Scarfiello, R. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Tunno, T. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Zacheo, A. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy)

    2014-05-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  3. Extreme variation of sulfur isotopic compositions in pyrite from the Qiuling sediment-hosted gold deposit, West Qinling orogen, central China: an in situ SIMS study with implications for the source of sulfur

    Science.gov (United States)

    Chen, Lei; Li, Xian-hua; Li, Jian-wei; Hofstra, Albert H.; Liu, Yu; Koenig, Alan E.

    2015-08-01

    High spatial resolution textural (scanning electron microscope (SEM)), chemical (electron microprobe (EMP)) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS)), and sulfur isotopic (secondary ion mass spectrometry (SIMS)) analyses of pyrite from the Qiuling sediment-hosted gold deposit (232 ± 4 Ma) in the West Qinling orogen, central China were conducted to distinguish pyrite types and gain insights into the source and evolution of sulfur in hydrothermal fluids. The results reveal an enormous variation (-27.1 to +69.6 ‰) in sulfur isotopic composition of pyrite deposited during three paragenetic stages. Pre-ore framboidal pyrite, which is characterized by low concentrations of As, Au, Cu, Co, and Ni, has negative δ34S values of -27.1 to -7.6 ‰ that are interpreted in terms of bacterial reduction of marine sulfate during sedimentation and diagenesis of the Paleozoic carbonate and clastic sequences, the predominant lithologies in the deposit area, and the most important hosts of many sediment-hosted gold deposits throughout the West Qinling orogen. The ore-stage hydrothermal pyrite contains high concentrations of Au, As, Cu, Sb, Tl, and Bi and has a relatively narrow range of positive δ34S values ranging from +8.1 to +15.2 ‰. The sulfur isotope data are comparable to those of ore pyrite from many Triassic orogenic gold deposits and Paleozoic sedimentary exhalative (SEDEX) Pb-Zn deposits in the West Qinling orogen, both being hosted mainly in the Devonian sequence. This similarity indicates that sulfur, responsible for the auriferous pyrite at Qiuling, was largely derived from the metamorphic devolatization of Paleozoic marine sedimentary rocks. Post-ore-stage pyrite, which is significantly enriched in Co and Ni but depleted in Au and As, has unusually high δ34S values ranging from +37.4 to +69.6 ‰, that are interpreted to result from thermochemical reduction of evaporite sulfates in underlying Cambrian sedimentary rocks with very

  4. Biomimetic thin film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Rieke, P.R.; Graff, G.E.; Campbell, A.A.; Bunker, B.C.; Baskaran, S.; Song, L.; Tarasevich, B.J.; Fryxell, G.E.

    1995-09-01

    Biological mineral deposition for the formation of bone, mollusk shell and other hard tissues provides materials scientists with illustrative materials processing strategies. This presentation will review the key features of biomineralization and how these features can be of technical importance. We have adapted existing knowledge of biomineralization to develop a unique method of depositing inorganic thin films and coating. Our approach to thin film deposition is to modify substrate surfaces to imitate the proteins found in nature that are responsible for controlling mineral deposition. These biomimetic surfaces control the nucleation and growth of the mineral from a supersaturated aqueous solution. This has many processing advantages including simple processing equipment, environmentally benign reagents, uniform coating of highly complex shapes, and enhanced adherence of coating. Many different types of metal oxide, hydroxide, sulfide and phosphate materials with useful mechanical, optical, electronic and biomedical properties can be deposited.

  5. 滇西北红山铜矿床成矿流体地球化学特征及矿床成因%Geochemical characteristics of ore-forming fluids and genesis of Hongshan copper deposit in northwestern Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    李文昌; 王可勇; 尹光侯; 秦丹鹤; 余海军; 薛顺荣; 万多

    2013-01-01

    The Hongshan copper deposit is a large porphyry-skarn type polymetallic deposit in northwestern Yunnan Province. It occurred in quartz diorite porphyry of Indo-Chinese Period and quartz monzonite porphyry of Yanshanian Period as well as their neighbouring wall rocks. The formation of it experienced superimposition of mutiphases/stages hydrothermal mineralization. Comprehensive study on petrography, microthermometry and carbon-hydrogen-oxygen isotope of fluid inclusions showed that the ore-forming fluids of early metallogenic stages are of medium to high temperature, high salinity NaCl-H2 O type solutions and mainly came from arc magmatism of Indo-Chinese Period, they were responsible for the formation of skarn type mineralization. The ore-forming fluids of later metallogenic stages are of medium to high temperature, high salinity NaCl-CO2 -H2 O type solutions and mainly came from the buried granitic magmatism of post orogenic extension environment, and they played important role in the formation of porphyry type Cu, Mo and relevant Pb, Zn mineralization. So the Hongshan copper deposit is of superimposed poyphyry-skarn type deposit that originated from the metallogenic superimposition of two phases of magmatic hydrothermal fluids.%红山铜矿床为滇西北地区一大型斑岩-矽卡岩型铜多金属矿床,它产于印支期石英闪长玢岩及燕山期石英二长斑岩体内及其周边地层中,其形成经历了多期次热液叠加成矿作用过程.流体包裹体岩相学、显微测温及碳、氢、氧稳定同位素综合研究表明,矿区早期成矿流体为中高温、高盐度NaCl-H2O体系热液,主要来源于印支晚期岛弧型岩浆活动,对区内矽卡岩型矿化形成起了重要作用;晚期成矿流体为中高温、高盐度NaCl-CO2-H2O体系热液,主要来源于隐伏的燕山期后造山伸展型花岗质岩浆侵入体,形成了区内斑岩型Cu、Mo及相关的Pb、Zn多金属矿化.因此,红山铜矿床是

  6. Re-Os isotopic ages of pyrite and chemical composition of magnetite from the Cihai magmatic-hydrothermal Fe deposit, NW China

    Science.gov (United States)

    Huang, Xiao-Wen; Zhou, Mei-Fu; Qi, Liang; Gao, Jian-Feng; Wang, Yu-Wang

    2013-12-01

    The Eastern Tianshan Orogenic Belt of the Central Asian Orogenic Belt and the Beishan terrane of the Tarim Block, NW China, host numerous Fe deposits. The Cihai Fe deposit (>90 Mt at 45.6 % Fe) in the Beishan terrane is diabase-hosted and consists of the Cihai, Cinan, and Cixi ore clusters. Ore minerals are dominantly magnetite, pyrite, and pyrrhotite, with minor chalcopyrite, galena, and sphalerite. Gangue minerals include pyroxene, garnet, hornblende and minor plagioclase, biotite, chlorite, epidotite, quartz, and calcite. Pyrite from the Cihai and Cixi ore clusters has similar Re-Os isotope compositions, with ˜14 to 62 ppb Re and ≤10 ppt common Os. Pyrrhotite has ˜5 to 39 ppb Re and ˜0.6 ppb common Os. Pyrite has a mean Re-Os model age of 262.3 ± 5.6 Ma ( n = 13), in agreement with the isochron regression of 187Os vs. 187Re. The Re-Os age (˜262 Ma) for the Cihai Fe deposit is within uncertainty in agreement with a previously reported Rb-Sr age (268 ± 25 Ma) of the hosting diabase, indicating a genetic relationship between magmatism and mineralization. Magnetite from the Cihai deposit has Mg, Al, Ti, V, Cr, Co, Ni, Mn, Zn, Ga, and Sn more elevated than that of typical skarn deposits, but both V and Ti contents lower than that of magmatic Fe-Ti-V deposits. Magnetite from these two ore clusters at Cihai has slightly different trace element concentrations. Magnetite from the Cihai ore cluster has relatively constant trace element compositions. Some magnetite grains from the Cixi ore cluster have higher V, Ti, and Cr than those from the Cihai ore cluster. The compositional variations of magnetite between the ore clusters are possibly due to different formation temperatures. Combined with regional tectonic evolution of the Beishan terrane, the Re-Os age of pyrite and the composition of magnetite indicate that the Cihai Fe deposit may have derived from magmatic-hydrothermal fluids related to mafic magmatism, probably in an extensional rift environment.

  7. The Nolans Bore rare-earth element-phosphorus-uranium mineral system: geology, origin and post-depositional modifications

    Science.gov (United States)

    Huston, David L.; Maas, Roland; Cross, Andrew; Hussey, Kelvin J.; Mernagh, Terrence P.; Fraser, Geoff; Champion, David C.

    2016-08-01

    Nolans Bore is a rare-earth element (REE)-U-P fluorapatite vein deposit hosted mostly by the ~1805 Ma Boothby Orthogneiss in the Aileron Province, Northern Territory, Australia. The fluorapatite veins are complex, with two stages: (1) massive to granular fluorapatite with inclusions of REE silicates, phosphates and (fluoro)carbonates, and (2) calcite-allanite with accessory REE-bearing phosphate and (fluoro)carbonate minerals that vein and brecciate the earlier stage. The veins are locally accompanied by narrow skarn-like (garnet-diopside-amphibole) wall rock alteration zones. SHRIMP Th-Pb analyses of allanite yielded an age of 1525 ± 18 Ma, interpreted as the minimum age of mineralisation. The maximum age is provided by a ~1550 Ma SHRIMP U-Pb age for a pegmatite that predates the fluorapatite veins. Other isotopic systems yielded ages from ~1443 to ~345 Ma, implying significant post-depositional isotopic disturbance. Calculation of initial ɛNd and 87Sr/86Sr at 1525 Ma and stable isotope data are consistent with an enriched mantle or lower crust source, although post-depositional disturbance is likely. Processes leading to formation of Nolans Bore began with north-dipping subduction along the south margin of the Aileron Province at 1820-1750 Ma, producing a metasomatised, volatile-rich, lithospheric mantle wedge. About 200 million years later, near the end of the Chewings Orogeny, this reservoir and/or the lower crust sourced alkaline low-degree partial melts which passed into the mid- and upper-crust. Fluids derived from these melts, which may have included phosphatic melts, eventually deposited the Nolans Bore fluorapatite veins due to fluid-rock interaction, cooling, depressurisation and/or fluid mixing. Owing to its size and high concentration of Th (2500 ppm), in situ radiogenic heating caused significant recrystallisation and isotopic resetting. The system finally cooled below 300 °C at ~370 Ma, possibly in response to unroofing during the Alice Springs

  8. The Nolans Bore rare-earth element-phosphorus-uranium mineral system: geology, origin and post-depositional modifications

    Science.gov (United States)

    Huston, David L.; Maas, Roland; Cross, Andrew; Hussey, Kelvin J.; Mernagh, Terrence P.; Fraser, Geoff; Champion, David C.

    2016-01-01

    Nolans Bore is a rare-earth element (REE)-U-P fluorapatite vein deposit hosted mostly by the ~1805 Ma Boothby Orthogneiss in the Aileron Province, Northern Territory, Australia. The fluorapatite veins are complex, with two stages: (1) massive to granular fluorapatite with inclusions of REE silicates, phosphates and (fluoro)carbonates, and (2) calcite-allanite with accessory REE-bearing phosphate and (fluoro)carbonate minerals that vein and brecciate the earlier stage. The veins are locally accompanied by narrow skarn-like (garnet-diopside-amphibole) wall rock alteration zones. SHRIMP Th-Pb analyses of allanite yielded an age of 1525 ± 18 Ma, interpreted as the minimum age of mineralisation. The maximum age is provided by a ~1550 Ma SHRIMP U-Pb age for a pegmatite that predates the fluorapatite veins. Other isotopic systems yielded ages from ~1443 to ~345 Ma, implying significant post-depositional isotopic disturbance. Calculation of initial ɛNd and 87Sr/86Sr at 1525 Ma and stable isotope data are consistent with an enriched mantle or lower crust source, although post-depositional disturbance is likely. Processes leading to formation of Nolans Bore began with north-dipping subduction along the south margin of the Aileron Province at 1820-1750 Ma, producing a metasomatised, volatile-rich, lithospheric mantle wedge. About 200 million years later, near the end of the Chewings Orogeny, this reservoir and/or the lower crust sourced alkaline low-degree partial melts which passed into the mid- and upper-crust. Fluids derived from these melts, which may have included phosphatic melts, eventually deposited the Nolans Bore fluorapatite veins due to fluid-rock interaction, cooling, depressurisation and/or fluid mixing. Owing to its size and high concentration of Th (2500 ppm), in situ radiogenic heating caused significant recrystallisation and isotopic resetting. The system finally cooled below 300 °C at ~370 Ma, possibly in response to unroofing during the Alice Springs

  9. Uranium hydrothermal deposits

    Czech Academy of Sciences Publication Activity Database

    René, Miloš

    New York : Nova Science Publishers, 2012 - (Vasiliev, A.; Sidorov, M.), s. 211-244 ISBN 978-1-62081-207-5 Institutional research plan: CEZ:AV0Z30460519 Keywords : uranium * hydrothermal deposits * uraninite Subject RIV: DB - Geology ; Mineralogy

  10. Speleothem (Cave Deposit) Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, and other aspects of climate derived from mineral deposits found in caves. Parameter keywords describe what was measured...

  11. Modeled Wet Nitrate Deposition

    Data.gov (United States)

    U.S. Environmental Protection Agency — Modeled data on nitrate wet deposition was obtained from Dr. Jeff Grimm at Penn State Univ. Nitrate wet depostion causes acidification and eutrophication of surface...

  12. Uranium deposit research, 1983

    International Nuclear Information System (INIS)

    Research on uranium deposits in Canada, conducted as a prerequisite for assessment of the Estimated Additional Resources of uranium, revealed that (a) the uranium-gold association in rudites of the Huronian Supergroup preferably occurs in the carbon layers; (b) chloritized ore at the Panel mine, Elliot Lake, Ontario, occurs locally in tectonically disturbed areas in the vicinity of diabase dykes; (c) mineralization in the Black Sturgeon Lake area, Ontario, formed from solutions in structural and lithological traps; (d) the Cigar Lake deposit, Saskatchewan, has two phases of mineralization: monomineralic and polymetallic; (e) mineralization of the JEB (Canoxy Ltd.) deposit is similar to that at McClean Lake; (f) the uranium-carbon assemblage was identified in the Claude deposit, Carswell Structure; and (g) the Otish Mountains area, Quebec, should be considered as a significant uranium-polymetallic metallogenic province

  13. Podiform chromite deposits

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Location and characteristics of 1,124 individual mineral deposits of this type, with grade and tonnage models for chromium as well as several related elements.

  14. Alluvial Deposits in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This coverage maps alluvial deposits throughout Iowa. This generally would include areas of alluvial soils associated with modern streams that are identified on...

  15. Automatic Payroll Deposit System.

    Science.gov (United States)

    Davidson, D. B.

    1979-01-01

    The Automatic Payroll Deposit System in Yakima, Washington's Public School District No. 7, directly transmits each employee's salary amount for each pay period to a bank or other financial institution. (Author/MLF)

  16. Metallic mineral deposits

    OpenAIRE

    Crow, M J; van Leeuwen, T.M.

    2005-01-01

    This account concentrates on the the primary metallic mineral deposits and occurrences in Sumatra, in particular the recent discoveries of gold, tin and base metals. The residual and placer deposits are given less emphasis, as no significant discoveries have been made in recent years. The history of mineral exploration and discovery in Indonesia has been reviewed recently by van Leeuwen (1993, 1994), documenting the change in emphasis of mineral-based activities from western to eastern I...

  17. Uranium deposits in Africa

    International Nuclear Information System (INIS)

    Africa is not only known for its spectacular diamond, gold, copper, chromium, platinum and phosphorus deposits but also for its uranium deposits. At least two uranium provinces can be distinguished - the southern, with the equatorial sub-province; and the south Saharan province. Uranium deposits are distributed either in cratons or in mobile belts, the first of sandstone and quartz-pebble conglomerate type, while those located in mobile belts are predominantly of vein and similar (disseminated) type. Uranium deposits occur within Precambrian rocks or in younger platform sediments, but close to the exposed Precambrian basement. The Proterozoic host rocks consist of sediments, metamorphics or granitoids. In contrast to Phanerozoic continental uranium-bearing sediments, those in the Precambrian are in marginal marine facies but they do contain organic material. The geology of Africa is briefly reviewed with the emphasis on those features which might control the distribution of uranium. The evolution of the African Platform is considered as a progressive reduction of its craton area which has been affected by three major Precambrian tectonic events. A short survey on the geology of known uranium deposits is made. However, some deposits and occurrences for which little published material is available are treated in more detail. (author)

  18. The mineral chemistry of hydrothermally altered and metamorphosed wall-rocks at the Stollberg Fe-Pb-Zn-Mn(-Ag) deposit, Bergslagen, Sweden

    Science.gov (United States)

    Ripa, M.

    1994-06-01

    The c. 1.9 Ga old Stollberg sulphide and Mnrich skarn iron ores and sulphide ores in Bergslagen, south-central Sweden are hosted by hydrothermally altered and metamorphosed felsic volcanic and volcaniclastic rocks. The ores are underlain by comformable alteration zones characterized by albite-gedrite-quartz and biotite-muscovite-plagioclase-K-feldspar-quartz +/- garnet assemblages. The present mineralogies are interpreted as medium-grade metamorphic equivalents to the original alteration mineral assemblages. PT-conditions during prograde regional metamorphism are semiquantatively determined to be 510 to 560 °C at approximately 3 kbar. With increasing modal content of gedrite and biotite in the alteration zones, the Mg/Fe ratios and XMg's in octahedral positions of these minerals also increase. In the gedrite-bearing strata, whole-rock Mg/Fe ratios remain constant, whereas in the biotite-rich unit the wholerock Mg/Fe trend is parallel to that of the biotites. The trends in the metamorphic mineral composition are interpreted to be a product of original changes in fluid composition during the evolution of a sub-seafloor hydrothermal system. During the initial stage of alteration, Fe-Mn-rich fluids altered the rocks, and during a later stage, the fluids became more Mg-rich, possibly due to entrainment of fresh seawater, and the alteration zones became relatively more Mg-rich. Sulphide precipitation was contemperaneous with Mg metasomatism, suggesting base metal precipitation was a function of the mixing of cool seawater with hydrothermal fluid. It is proposed that early hydrothermal alteration was associated with the deposition of areally extensive Fe-oxide formation, and that Mg metasomatism defines a second stage of hydrothermal activity during which sulphide mineralization overprinted the earlier formed Fe-oxide deposit.

  19. Molybdenite occurrences in Greece: mineralogy, geochemistry and depositional environment

    OpenAIRE

    Voudouris, P.; Melfos, V.; Moritz, Robert; Spry, P. G.; Ortelli, Mélissa; Kartal, T.

    2010-01-01

    Molybdenite occurs mainly in three mineralization types in Greece: (a) porphyry Mo-Cu-(±Te-Ag-Au), (b) reduced intrusion-related Mo-W systems (skarn, intrusion-hosted) and (c) shear zone-related Cu-Au-Bi-Mo. In porphyry-Mo-Cu prospects the molybdenite is the main ore constituent together with pyrite in quartz stockworks crosscutting sericite±carbonate altered porphyry stocks (dacite at Pagoni Rachi/Kirki, Myli/Esymi, Konos/Sapes, Melitena/Rhodopi and Stypsi/Lesvos; microgranite at Ktismata/Ma...

  20. Gaseous transport and deposition of gold in magmatic fluid: evidence from the active Kudryavy volcano, Kurile Islands

    Science.gov (United States)

    Yudovskaya, Marina A.; Distler, Vadim V.; Chaplygin, Ilya V.; Mokhov, Andrew V.; Trubkin, Nikolai V.; Gorbacheva, Sonya A.

    2006-03-01

    The distribution of gold in high-temperature fumarole gases of the Kudryavy volcano (Kurile Islands) was measured for gas, gas condensate, natural fumarolic sublimates, and precipitates in silica tubes from vents with outlet temperatures ranging from 380 to 870°C. Gold abundance in condensates ranges from 0.3 to 2.4 ppb, which is significantly lower than the abundances of transition metals. Gold contents in zoned precipitates from silica tubes increase gradually with a decrease in temperature to a maximum of 8 ppm in the oxychloride zone at a temperature of approximately 300°C. Total Au content in moderate-temperature sulfide and oxychloride zones is mainly a result of Au inclusions in the abundant Fe-Cu and Zn sulfide minerals as determined by instrumental neutron activation analysis. Most Au occurs as a Cu-Au-Ag triple alloy. Single grains of native gold and binary Au-Ag alloys were also identified among sublimates, but aggregates and crystals of Cu-Au-Ag alloy were found in all fumarolic fields, both in silica tube precipitates and in natural fumarolic crusts. Although the Au triple alloy is homogeneous on the scale of microns and has a composition close to (Cu,Ni,Zn)3(Au,Ag)2, transmission electron microscopy (TEM) shows that these alloy solid solutions consist of monocrystal domains of Au-Ag, Au-Cu, and possibly Cu2O. Gold occurs in oxide assemblages due to the decomposition of its halogenide complexes under high-temperature conditions (650-870°C). In lower temperature zones (behavior is related to sulfur compounds whose evolution is strongly controlled by redox state. Other minerals that formed from gas transport and precipitation at Kudryavy volcano include garnet, aegirine, diopside, magnetite, anhydrite, molybdenite, multivalent molybdenum oxides (molybdite, tugarinovite, and ilsemannite), powellite, scheelite, wolframite, Na-K chlorides, pyrrhotite, wurtzite, greenockite, pyrite, galena, cubanite, rare native metals (including Fe, Cr, Mo, Sn, Ag, and

  1. Vein type uranium deposits

    International Nuclear Information System (INIS)

    Veins are tabular- or sheet-like masses of minerals occupying or following a fracture or a set of fractures in the enclosing rock. They have been formed later than the country rock and fractures, either by filling of the open spaces or by partial or complete replacement of the adjoining rock or most commonly by both of these processes combined. This volume begins with the occurrences and deposits known from old shield areas and the sedimentary belts surrounding them. They are followed by papers describing the European deposits mostly of Variscan age, and by similar deposits known from China being of Jurassic age. The volume is completed by two papers which do not fit exactly in the given scheme. A separate abstract was prepared for each of the 25 papers in this report

  2. 广东梅子冲银多金属矿床地质特征及找矿方向%Geological characteristics and prospecting direction of Meizichong silver-polymetallic deposit in Guangdong

    Institute of Scientific and Technical Information of China (English)

    吴剑

    2015-01-01

    韶关梅子冲银多金属矿床位于南岭成矿带中部一六矿田内,矿体赋存于下石炭统孟公坳组不纯灰岩中,属于典型的矽卡岩型矿床,矿床成矿元素地表分带和钻孔中的垂向分带现象明显。主成矿元素银主要以独立矿物和类质同象混入物形式赋存于方铅矿等硫化物中。文章通过矿床地质特征的分析,对矿床成因进行了初步的探讨,并提出了下一步本区的找矿方向。%Meizichong silver-polymetallic deposit belongs to typical skarn type which located inner Yiliu ore field of central Naling metallogenic belt and its ore bodies occur in impure limestone of Menggongao group of Lower Carboniferous Series.The horizontal zoning in surface and vertical zoning in drill hole of metallogenic elements in this deposit are clear.Main metallogenic element of silver is occurrence in sulfide such as galena with independent minerals and isomorphous addition.Base on analysis to geological characteristics,the de-posit genesis has carried on the preliminary discussion,and prospecting direction for further exploration has been pointed out.

  3. Geological features and geochemical characteristics of Laoyaling copper deposit in Tongling,Anhui province%安徽省铜陵老鸦岭铜矿床地质特征及地球化学特征

    Institute of Scientific and Technical Information of China (English)

    徐方颖; 赖健清; 王雄军

    2015-01-01

    老鸦岭铜矿床是冬瓜山矿区内一个层控矽卡岩型矿床。区内主要出露三叠系地层,青山背斜是主要褶皱构造,侵入岩以燕山期中酸性岩体为主。矿体呈多层产在下二叠统至下三叠统的远离主接触带的大理岩地层中。矿区内的地层和岩体可能受同一流体的影响;地层和燕山期流体均为成矿提供稀土元素;矿床不同的元素异常组合对成矿有不同的指示作用。%The Laoyaling copper deposit,located in the Dongguashan mining area,is a stratabound skarn type deposit.The main outcropped strata are limestone and dolomite of Triassic.Qingshan anticline is the main fold structure and Yanshanian intermediate-acidic magmatic rocks are the major intrusive rocks in the mining area.Orebodies mainly occur in Lower Permain-Lower Triassic marbles,far from the main contact zone. The formation and diorite in the mining area may be affected by the same fluid.Both formation and forming fluid of Yanshanian magmatic rocks provide REE for orebody.The different element anomaly combination of the deposit play different role of metallogenic environment.

  4. Ages and sources of components of Zn-Pb, Cu, precious metal, and platinum group element deposits in the goodsprings district, clark county, Nevada

    Science.gov (United States)

    Vikre, P.; Browne, Q.J.; Fleck, R.; Hofstra, A.; Wooden, J.

    2011-01-01

    The Goodsprings district, Clark County, Nevada, includes zinc-dominant carbonate replacement deposits of probable late Paleozoic age, and lead-dominant carbonate replacement deposits, copper ?? precious metal-platinum group element (PGE) deposits, and gold ?? silver deposits that are spatially associated with Late Triassic porphyritic intrusions. The district encompasses ??500 km2 although the distribution of all deposits has been laterally condensed by late Mesozoic crustal contraction. Zinc, Pb, and Cu production from about 90 deposits was ??160,000 metric tons (t) (Zn > Pb >> Cu), 2.1 million ounces (Moz) Ag, 0.09 Moz Au, and small amounts of PGEs-Co, V, Hg, Sb, Ni, Mo, Mn, Ir, and U-were also recovered. Zinc-dominant carbonate replacement deposits (Zn > Pb; Ag ?? Cu) resemble Mississippi Valley Type (MVT) Zn-Pb deposits in that they occur in karst and fault breccias in Mississippian limestone where the southern margin of the regional late Paleozoic foreland basin adjoins Proterozoic crystalline rocks of the craton. They consist of calcite, dolomite, sphalerite, and galena with variably positive S isotope compositions (??34S values range from 2.5-13%), and highly radiogenic Pb isotope compositions (206Pb/204Pb >19), typical of MVT deposits above crystalline Precambrian basement. These deposits may have formed when southward flow of saline fluids, derived from basinal and older sedimentary rocks, encountered thinner strata and pinch-outs against the craton, forcing fluid mixing and mineral precipitation in karst and fault breccias. Lead-dominant carbonate replacement deposits (Pb > Zn, Ag ?? Cu ?? Au) occur among other deposit types, often near porphyritic intrusions. They generally contain higher concentrations of precious metals than zinc-dominant deposits and relatively abundant iron oxides after pyrite. They share characteristics with copper ?? precious metal- PGE and gold ?? silver deposits including fine-grained quartz replacement of carbonate minerals in

  5. "Total Deposition (TDEP) Maps"

    Science.gov (United States)

    The presentation provides an update on the use of a hybrid methodology that relies on measured values from national monitoring networks and modeled values from CMAQ to produce of maps of total deposition for use in critical loads and other ecological assessments. Additionally, c...

  6. Thorium ore deposits

    International Nuclear Information System (INIS)

    The main occurences of the thorium minerals of the Argentine Republic which have not been exploited, due to their reduced volume, are described. The thoriferous deposits have three genetic types: pegmatitic, hydrothermal and detritic, being the most common minerals: monazite, thorite and thorogummite. The most important thorium accumulations are located in Salta, being of less importance those of Cordoba, Jujuy and San Juan. (M.E.L.)

  7. Uranium deposits of Brazil

    International Nuclear Information System (INIS)

    Brazil is a country of vast natural resources, including numerous uranium deposits. In support of the country's nuclear power program, Brazil has developed the most active uranium industry in South America. Brazil has one operating reactor (Angra 1, a 626-MWe PWR), and two under construction. The country's economic challenges have slowed the progress of its nuclear program. At present, the Pocos de Caldas district is the only active uranium production. In 1990, the Cercado open-pit mine produced approximately 45 metric tons (MT) U3O8 (100 thousand pounds). Brazil's state-owned uranium production and processing company, Uranio do Brasil, announced it has decided to begin shifting its production from the high-cost and nearly depleted deposits at Pocos de Caldas, to lower-cost reserves at Lagoa Real. Production at Lagoa Real is schedules to begin by 1993. In addition to these two districts, Brazil has many other known uranium deposits, and as a whole, it is estimated that Brazil has over 275,000 MT U3O8 (600 million pounds U3O8) in reserves

  8. Intricately Rippled Sand Deposits

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Click on the image for Intricately Rippled Sand Deposits (QTVR) NASA's Mars Exploration Rover Spirit welcomed the beginning of 2006 on Earth by taking this striking panorama of intricately rippled sand deposits in Gusev Crater on Mars. This is an approximate true-color rendering of the 'El Dorado' ripple field provided by Spirit over the New Year's holiday weekend. The view spans about 160 degrees in azimuth from left to right and consists of images acquired by Spirit's panoramic camera on Spirit's 708th and 710th Martian days, or sols, (Dec. 30, 2005 and Jan. 1, 2006). Spirit used the Pancam's 750-nanometer, 530-nanometer and 430-nanometer filters to capture the colors on Mars. Scientists have eliminated seams between individual frames in the sky portion of the mosaic to better simulate the vista a person standing on Mars would see. Spirit spent several days acquiring images, spectral data, and compositional and mineralogical information about these large sand deposits before continuing downhill toward 'Home Plate.'

  9. Fluid inclusion and phase equilibrium studies at the Cannivan Gulch molybdenum deposit, Montana, USA: Effect of CO 2 on molybdenite-powellite stability

    Science.gov (United States)

    Darling, Robert S.

    1994-01-01

    The molybdenum deposit at Cannivan Gulch is characterized by both stockwork- and skarn type mineralization. The vein mineral assemblages, however, differ considerably between the various host rocks. In the Cannivan stock, molybdenite occurs in typical quartz + K-feldspar or quartz + muscovite veins. In the country rocks, molybdenite occurs in chlorite + pyrite + magnetite veins containing variable amounts of quartz, calcite, and epidote. Primary fluid inclusions in quartz and fluorite contain aqueous liquid, CO 2 liquid, and CO 2 vapor (average XCO2 = 0.05). Microthermometric and Laser Raman microspectrographic analyses indicate CO 2 is the principal volatile phase. First melting temperatures in the aqueous portion indicate the dissolved salt is principally NaCl. Final CO 2-clathrate melting temperatures indicate NaCl contents ranging from 2 to 7 wt% relative to H 2O. Homogenization temperatures range from 196 to 272°C. Four chlorite temperatures from two samples range from 296 to 319°C. In P- T space, the four chlorite univariants intersect four fluid inclusion isochores (from the same samples) at temperatures of 300 ± 20° C and 1500 ± 300 bars, which are the inferred P and T of molybdenite formation. Mineral equilibria in vein assemblages from country rocks at Cannivan Gulch indicate fO2 and fS2 conditions of molybdenite formation between the pyrite-pyrrhotite-magnetite and pyrite-magnetite-hematite buffers. Formation of a calcite-molybdenite assemblage over powellite suggests that even small amounts of CO 2 ( XCO2 = 0.05) in an ore fluid greatly extend the stability field of molybdenite to higher oxygen fugacities.

  10. Origin of REE mineralization in the Bastnäs-type Fe-REE-(Cu-Mo-Bi-Au) deposits, Bergslagen, Sweden

    Science.gov (United States)

    Holtstam, Dan; Andersson, Ulf B.; Broman, Curt; Mansfeld, Joakim

    2014-12-01

    The Bastnäs-type deposits, with mineral assemblages of Fe oxides, Ca-Mg silicates, rare earth element (REE) silicates, REE fluorocarbonates, and Cu-Fe-Mo-Bi sulfides, are associated with marble horizons in a strongly Na, K, and/or Mg altered, metavolcanic succession, over a distance of at least 80 km in a SW-NE trending zone in western Bergslagen. Two subtypes occur: (1) enriched (relative to the other type) in light REE (LREE) and Fe, exemplified by the Bastnäs and Rödbergsgruvan deposits, and (2) enriched in heavy REE (HREE), Y, Mg, Ca, and F, represented by deposits in the Norberg district. Bastnäsite hosts primary fluid H2O-CO2 inclusions with salinities of 6-29 eq. wt% CaCl2 and with total homogenization temperatures ( Th tot) of ca. 300-400 °C. Subtype 2 has late-stage fluorite with fluid inclusions that show 1-16 eq. wt% NaCl and Th tot of ca. 90-150 °C. Molybdenite Re-Os ages obtained from three deposits are 1,904 ± 6, 1,863 ± 4, and 1,842 ± 4 Ma. Nd isotopic data from five different REE minerals yielded no defined isochron, but a range in ɛNd (1.88 Ga) of +0.2 to +1.6. The oxygen isotope values (δ18OSMOW) of dolomite and calcite from the associated REE-mineralized skarn and recrystallized carbonate assemblages lie in the range 6.1-8.6 ‰, overlapping with those of the host marbles. Carbon isotope values (δ13CPDB) show typical magmatic signatures of -6.7 to -4.4 ‰, while the host marbles group around ca. -2.4 ‰. The sulfur isotope (δ34SCDT) values of associated sulfides range between -10.8 and +0.2 ‰. The combined evidence suggests REE mineralization, beginning at 1.9 Ga, from mainly Svecofennian, juvenile magmatic (>400 °C) fluids carrying Si, F, Cl, S, CO2, and the REE in addition to other metals; mineralization occurred through reactions with dolomitic layers in the supracrustal units coevally with regional metasomatic alteration associated with fluid circulation through an extensive active volcano-plutonic complex.

  11. The classification of minerals deposits

    International Nuclear Information System (INIS)

    In this part of book author present the classification of minerals deposits. Deposit formation take place as a result of complicated and long geology processes in the wide temperature intervals (from 1500 digC to usual) and pressures (from usual and to tens kilobars). Deposits of minerals as other investigation objects require in definite systematization on the base of definite characteristics

  12. HEDL sodium vapor deposit experience

    International Nuclear Information System (INIS)

    Sodium vapor deposits can affect reactor component operation and maintenance. Recorded cases include plugged cover gas lines and cementation of rotating components or sliding surfaces. Deposits found on plant scale components after testing in sodium were measured. Laboratory tests show the effect of Na pool temperature and condenser geometry on deposit accumulation rates and viewport fogging

  13. Limited Deposit Insurance Coverage and Bank Competition

    OpenAIRE

    Shy, Oz; Stenbacka, Rune; Yankov, Vladimir

    2014-01-01

    Deposit insurance designs in many countries place a limit on the coverage of deposits in each bank. However, no limits are placed on the number of accounts held with different banks. Therefore, under limited deposit insurance, some consumers open accounts with different banks to achieve higher or full deposit insurance coverage. We compare three regimes of deposit insurance: No deposit insurance, unlimited deposit insurance, and limited deposit insurance. We show that limited deposit insuranc...

  14. 40Ar-39Ar Dating of Sericite in the Nongruri Gold Deposit of Tibet and its Geological Significance%西藏弄如日金矿床蚀变绢云母40Ar-39Ar年龄及其地质意义

    Institute of Scientific and Technical Information of China (English)

    黄瀚霄; 李光明; 董随亮; 石洪召; 刘波; 张智林

    2012-01-01

    The Nongruri gold deposit is located in Gangdise-Himalaya metallogenio belt, southern Qinghai-Tibet plateau- The mineralization was strictly controlled by the SN fault. The Nongruri gold deposit is the first epithermal Au deposit discovered in the Gangdese metallogenic belt. The ore-forming age of the Nongruri gold deposit is still in dispute. In order to obtain the ore-forming age, the authors measured the sericites separated from the altered granite-porphyry which hosts the gold deposit. The Ar- Ar analyses yield weighted average age and isochron age of (19.87 ±0.96) Ma and (19.70 ±0. 30) Ma, respectively. It is held that the Au mineralization in the Nongruri deposit took place in Miocene, which is consistent with the ore-forming epoch of the porphyry copper ore deposits in the adjacent regions. This suggests that the Nongruri epithermal Au deposit, the skarn polymetallic copper deposits, and the porphyry copper ore deposits were formed in the same magma-fluid mineralization system controlled by an extensional dynamic setting in the Gangdise belt.%西藏弄如日金矿是冈底斯成矿带发现的第一个浅成低温热液型金矿床.为确定金矿床的成矿时代,对该矿床与金矿化有关的蚀变花岗斑岩中绢云母进行了40Ar-39Ar年龄测试,获得绢云母的加权平均年龄和等时线年龄分别为19.87±0.96 Ma和19.70±0.30 Ma.结果表明,弄如日金矿床金矿化的主要成矿时代为中新世.该成果的获得对于进一步认识弄如日金矿成因机制、地球动力学背景以及区域找金突破具有重要意义.

  15. MOF作模板制备多孔Au/CuxO催化剂及其CO氧化性能%MOF-templated preparation of porous Au/CuxO catalysts with octahedral structures for CO oxidation

    Institute of Scientific and Technical Information of China (English)

    刘朋飞; 张所瀛; 杨祝红; 陆小华

    2016-01-01

    采用MOF材料作模板,通过在Cu-BTC材料表面预先负载贵金属Au再热解的方法,成功制备了具有正八面体结构的新型多孔Au/CuxO负载型催化剂。通过降低热解环境中的O2浓度,调节氧化时间,实现了Au/Cu-BTC氧化产物组分的调节,分别制得了Au/Cu2O、Au/Cu2O-CuO、Au/CuO复合催化材料。将其用于CO催化氧化,发现所有Au/CuxO催化剂都表现出比Cu-BTC和Au/Cu-BTC更优异的催化性能,其中由于拥有较高的比表面积、Cu2O含量以及更好的Au的分散性,Au/Cu2O的CO氧化活性最佳,180℃即能实现CO的完全转化。%More recently, metal-organic frameworks (MOFs), as a excellent sacrificial template, have been widely used to fabricate a variety of porous metal oxides with special structures and performances. To take full advantage of MOFs in composition regulation, herein a novel method to prepare porous Au/CuxO composites with octahedral structures inherited from MOFs was introduced. Au/Cu-BTC was firstly prepared by the traditional deposition-precipitation method. Subsequently, pyrolysis of Au/Cu-BTC was conducted in 2% (volume fraction) O2 balanced with helium. By varying the time of heating, Au/CuxO composites including Au/Cu2O, Au/Cu2O-CuO and Au/CuO were successfully achieved. When tested in CO oxidation, these supported catalysts exhibited much better catalytic performances than Cu-BTC and Au/Cu-BTC due to the more active support of metal oxides. Thus, Au/Cu2O showed the best catalytic activity since the high surface area, Cu2O content and better dispersion of Au.

  16. Deposition of carbon dioxide

    International Nuclear Information System (INIS)

    In Norway, there is currently a debate about whether or not to build gas power stations. To meet the possibility of reduced emission quotas for carbon dioxide in the future, current interest focuses on the incorporation of large-scale separation and deposition of carbon dioxide when such plants are planned. A group of experts concludes that this technology will become self-financing by means of environmental taxes. From the environmental point of view, taxes upon production are to be preferred over taxes on consumption

  17. Uranium ore deposits

    International Nuclear Information System (INIS)

    The main uranium deposits and occurrences in the Argentine Republic are described, considering, in principle, their geologic setting, the kind of 'model' of the mineralization and its possible origin, and describing the ore species present in each case. The main uraniferous accumulations of the country include the models of 'sandstong type', veintype and impregnation type. There are also other kinds of accumulations, as in calcrete, etc. The main uranium production has been registered in the provinces of Mendoza, Salta, La Rioja, Chubut, Cordoba and San Luis. In each case, the minerals present are mentioned, having been recognized 37 different species all over the country (M.E.L.)

  18. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    Three overall factors are necessary for formation of uranium deposits in sandstone: a source of uranium, host rocks capable of transmitting uranium-bearing solutions, and a precipitant. Possible sources of uranium in sandstone-type deposits include groundwaters emanating from granitic highlands, arkosic sediments, tuffaceous material within or overlying the host rocks, connate fluids, and overlying black shales. The first three sources are considered the most likely. Host rocks are generally immature sandstones deposited in alluvial-fan, intermontane-basin or marginal-marine environments, but uranium deposits do occur in well-winnowed barrier-bar or eolian sands. Host rocks for uranium deposits generally show coefficients of permeability on the order of 1 to 100 gal/day/ft2. Precipitants are normally agents capable of reducing uranium from the uranyl to the uranous state. The association of uranium with organic matter is unequivocal; H2S, a powerful reductant, may have been present at the time of formation of some deposits but may go unnoticed today. Vanadium can serve to preserve the tabular characteristics of some deposits in the near-surface environment, but is considered an unlikely primary precipitant for uranium. Uranium deposits in sandstone are divided into two overall types: peneconcordant deposits, which occur in locally reducing environments in otherwise oxidized sandstones; and roll-type deposits, which occur at the margin of an area where an oxidized groundwater has permeated an otherwise reduced sandstone. Uranium deposits are further broken down into four subclasses; these are described

  19. MOSES AND DENNISON PEAK ROADLESS AREAS, CALIFORNIA.

    Science.gov (United States)

    Goldfarb, Richard J.; Lipton, David A.

    1984-01-01

    A mineral-resource survey was conducted in the Moses and Dennison Peak Roadless Areas, southeastern Sierra Nevada, California. One area within the Moses Roadless Area is classified as having substantiated mineral-resource potential for small base-metal skarn deposits. Additionally, geochemical data indicate probable potential for small base-metal skarn deposits from one locality within Dennison Peak Roadless Area and for small tungsten skarn deposits from a region within Moses Roadless Area. The geologic setting precludes the presence of energy resources.

  20. FDIC Summary of Deposits (SOD) Download File

    Data.gov (United States)

    Federal Deposit Insurance Corporation — The FDIC's Summary of Deposits (SOD) download file contains deposit data for branches and offices of all FDIC-insured institutions. The Federal Deposit Insurance...

  1. 澳大利亚 Hillside 铁氧化物型铜-金矿床地质特征%Geological Characteristics of Hillside Iron Oxide Copper Gold Deposit in Australia

    Institute of Scientific and Technical Information of China (English)

    丁绍磊; 鲁文华; 阳正熙; 梁学玉

    2016-01-01

    Hillside 铁氧化物型铜-金(Iron oxide copper gold,IOCG)矿床是近年来在南澳大利亚奥林匹克铜-金成矿省中发现的又一大型 IOCG 矿床。区内出露 Hiltaba 辉长岩体及花岗岩体,SN走向的矿体赋存于岩体与 Moonta-Wallaroo 地层的接触带内。SN 向的 Pinepoint 构造断裂带为区内主要的控矿构造,为成矿物质提供了运移通道和富集场所。区内主要矿石矿物有黄铜矿、黄铁矿、磁铁矿、赤铁矿等,矿化阶段可分为早期矽卡岩阶段、晚期矽卡岩阶段、成矿阶段,热液蚀变可分为早期高温蚀变阶段、进变质蚀变阶段、退变质蚀变阶段。基于区内已有的大量勘探资料,在详细分析矿区地质特征、矿床地质特征的基础上,对区内控矿因素进行了探讨,并分别从地层岩性、构造、岩浆岩、围岩蚀变、重磁异常等方面归纳了找矿标志,为区内找矿工作提供参考。%The hillside iron oxide copper gold (IOCG)deposit is another large-size IOCG deposit, which is discovered recently in Olympic copper and gold metallogenetic province in southern Australia. The outcrop of Hiltaba gabbros and granites can be observed in the mining area.SN striking ore-body is hosted by the contacted zone of intrusive and rocks of Mount Wallaroo group.SN striking Pinepoint fault zone is the main ore-controlling structure in the mining area,which supply the metallogenic materials transporting aisle and metallogenic convergence.The main ore minerals are chalcopyrite,pyrite,magne-tite,hematite etc,the mineralization stages can be divided into three stages:early skarn stage,late skarn stage and metallogenic stage,the hydrothermal alteration can be divided into three stages:early high tem-perature alteration,prograde alteration and retrograde alteration.Combing with the large amount of the geological exploration data of the mining area,based on analyzing the geological characteristics of the mining area

  2. Lunar western limb pyroclastic deposits

    Science.gov (United States)

    Coombs, Cassandra R.; Hawke, B. Ray

    1991-01-01

    It has become increasingly evident that the lunar pyroclastic volcanism played an important role in the formation and resurfacing of many areas of the Moon. On-going analysis of lunar Orbiter and Apollo photographs continues to locate and identify pyroclastic deposits and suggests that they just may be more ubiquitous than once thought. Located near mare/highland boundaries, many of these deposits formed contemporaneously with effusive mare volcanism. The mantling deposits formed as products of fire-fountaining. Probable source vents for these deposits include irregular depressions at the head of associated sinuous rilles and/or along irregular fractures in the floors of ancient craters. Here, researchers provide a brief synopsis of the nature of the dark mantling deposits and briefly discuss several newly identified deposits on the western limb.

  3. A remote coal deposit revisited

    DEFF Research Database (Denmark)

    Bojesen-Kofoed, Jørgen A.; Kalkreuth, Wolfgang; Petersen, Henrik I.;

    2012-01-01

    In 1908, members of the “Danmark Expedition” discovered a coal deposit in a very remote area in western Germania Land, close to the margin of the inland ice in northeast Greenland. The deposit was, however, neither sampled nor described, and was revisited in 2009 for the first time since its...... discovery. The outcrops found in 2009 amount to approximately 8 m of sediment including a coal seam of 2 m thickness. More outcrops and additional coal deposits most certainly are to be found, pending further fieldwork. The deposits are Middle Jurassic, Callovian, in age and were deposited in a floodplain...... environment related to meandering river channels. Spores and pollen in the lower fluvial deposits reflect abundant vegetation of ferns along the river banks. In contrast, a sparse spore and pollen flora in the coals show a mixed vegetation of ferns and gymnosperms. Based on proximate and petrographic analyses...

  4. Momentum Deposition in Curvilinear Coordinates

    Energy Technology Data Exchange (ETDEWEB)

    Cleveland, Mathew Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lowrie, Robert Byron [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rockefeller, Gabriel M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thompson, Kelly Glen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wollaber, Allan Benton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-03

    The momentum imparted into a material by thermal radiation deposition is an important physical process in astrophysics and inertial confinement fusion (ICF) simulations. In recent work we presented a new method of evaluating momentum deposition that relies on the combination of a time-averaged approximation and a numerical integration scheme. This approach robustly and efficiently evaluates the momentum deposition in spherical geometry. Future work will look to extend this approach to 2D cylindrical geometries.

  5. MINERALIZATION CHARACTERISTICS AND METALLOGENETIC MODEL OF DUSHAN SN DEPOSIT IN THE EASTERN PART OF THE SOUTH TIANSHAN MOUNTAIN%南天山独山锡矿床的成矿特征及成矿模式

    Institute of Scientific and Technical Information of China (English)

    张子敏; 马汉峰; 蔡根庆

    2001-01-01

    Based on micro and macro-scopic researches, the pre-existinghypothesis that the genesis of Shenshashui Sn deposit belongs to skarn-type is denied. It is proposed that the Sn mineralizations are linked to the intrusion of the early Permian alkali granite and filling of thermal solutions, and are also controlled by faults and fracture zones. Directed by this new viewpoint, we discovered the Dushan Sn deposit which is related to early Permian K-feldspar granite porphyry in the eastern part of the south Tianshan Mountain for the first time. Though detailed researches have been done on alterations, activities of metallogenic period and existing forms of Sn in ores,three metallogenic stages of the deposit have been determined, namely cassiterite-and carbonate metasomatism-filling stage, cassiterite-quartz-iron minerals filling stage, and cassiterite-quartz - sulfides filling stage. According to the features of stable isotopes and rare earth elements, the genesis of the deposit is discussed and the metallogenic model for the deposit is established.%通过对渗沙水锡矿点宏、微观研究,否定了原矽卡岩型锡矿的成因观点,提出锡矿化与早二叠世末碱长花岗岩侵入和热液充填交代有关,矿化受断裂破碎构造控制。以此新观点为指导,我们在南天山东段首次发现了与早二叠世末钾长花岗斑岩有关的成型锡矿床--独山锡矿床。从蚀变、矿期活动及矿石中锡的存在形式等方面对该矿床进行了详细研究,确定了该矿床的形成包括锡石-泥晶碳酸盐充填交代、锡石-石英-铁矿物充填及锡石-石英-硫化物充填3个成矿阶段。根据稳定同位素、稀土特征对矿床成因进行了探讨,并建立了矿床成矿模式。

  6. Enhanced nitrogen deposition over China

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xuejun; Zhang, Ying; Han, Wenxuan; Tang, Aohan; Shen, Jianlin; Cui, Zhenling; Christie, Peter; Zhang, Fusuo [College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Vitousek, Peter [Department of Biology, Stanford University, Stanford, California 94305 (United States); Erisman, Jan Willem [VU University Amsterdam, 1081 HV Amsterdam (Netherlands); Goulding, Keith [The Sustainable Soils and Grassland Systems Department, Rothamsted Research, Harpenden AL5 2JQ (United Kingdom); Fangmeier, Andreas [Institute of Landscape and Plant Ecology, University of Hohenheim, 70593 Stuttgart (Germany)

    2013-02-28

    China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P < 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures. Nitrogen from ammonium (NH4+) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3-), in agreement with decreased ratios of NH3 to NOx emissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment.

  7. Self-generated etchant for synthetic sculpturing of Cu 2O-Au, Cu 2O@Au, Au/Cu 2O, and 3D-Au nanostructures

    KAUST Repository

    Pang, Maolin

    2012-10-09

    Structures of Gold: A simple transformative method for nanoscale sculpturing has been developed. Five different types of complex nanocomposites of cuprite and gold have been formed by using this self-etching approach (see figure). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Cherts from the Yangla copper deposit, western Yunnan Province: geochemical characteristics and relationship with massive sulfide mineralization

    Institute of Scientific and Technical Information of China (English)

    PAN; Jiayong; (

    2001-01-01

    [1]Wei Junqi, Zhan Mingguo, Lu Yuanfa et al., Geochemistry of granitoid from the Yangla ore district, Geology and Mineral Resources of South China (in Chinese), 1997 (4): 50.[2]He Longqing, Zhan Mingguo, Lu Yuanfa, Division of sequence stratigraphy and study on ore-bearing beds in the Yangla copper orefield, western Yunnan, Geology and Mineral Resources of South China (in Chinese), 1998 (3): 37.[3]Zhan Mingguo, Lu Yuanfa, Chen Shifang et al., Formation condition and type of the Yangla large scale copper deposit, Western Yunnan, Mineral Deposits (in Chinese), 1998, 17 (supplement): 183.[4]Lu Yuanfa, Chen Kaixu, Zhan Mingguo et al., Geochemical evidence of exhalative-sedimentary ore-bearing skarns in Yangla copper mineralization concentrated Area, Earth Science (in Chinese), 1999, 24(3): 298.[5]Yomamoto, K., Geochemical characteristics and depositional environments of cherts and associated rocks in the Franciscan and Shimanto terranes, Sedimentary Geology, 1987, 52: 65.[6]Zhou, Y. Z., Geochemical characteristics of siliceous rocks originated from a fossil hydrothermal system in the upper Devonian strata, Guangxi, southern China, Acta Sedimentologia, 1990, 8 (3): 75.[7]Zhou Yongzhang, Geology and Geochemistry of Hetai Gold Field, Southern China, Guangzhou: South China University of Technology Press, 1993, 53-107.[8]Bostroem, K., Harold, R., Oiva, J., Provenance and accumulation rates of opaline silica, Al, Fe, Tl, Mn, Cu, Ni and Co in Pacific pelagic sediment, Chem. Geol., 1973, 11: 123.[9]Herzig, P. M., Becker, K. P., Stoffers, P. et al., Hydrothermal silica chimney field in the Galapagos rift center at 81°W, Earth Pla. Sci. Lett., 1987, 52: 65.[10] Douthitt, C. B., The geochemistry of the stable isotopes of the silicon, Geochim. Cosmochim. Acta, 1982, 16: 129.[11] Ying Hanlong, Cai Xinping, Liu Bingguang, Geochemical features and formation of auriferous cherts in Mojiang Gold Mine, Yunnan, Geochemistry (in Chinese), 1999

  9. Liquefier Dynamics in Fused Deposition

    DEFF Research Database (Denmark)

    Bellini, Anna; Guceri, Selcuk; Bertoldi, Maurizio

    2004-01-01

    Layered manufacturing (LM) is an evolution of rapid prototyping (RP) technology whereby a part is built in layers. Fused deposition modeling (FDM) is a particular LM technique in which each section is fabricated through vector style deposition of building blocks, called roads, which are then...

  10. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    World-class sandstone-type uranium deposits are defined as epigenetic concentrations of uranium minerals occurring as uneven impregnations and minor massive replacements primarily in fluvial, lacustrine, and deltaic sandstone formations. The main purpose of this introductory paper is to define, classify, and introduce to the general geologic setting for sandstone-type uranium deposits

  11. Deposition and Resuspension of Particles

    DEFF Research Database (Denmark)

    Lengweiler, P.; Nielsen, Peter V.; Moser, A.;

    A new experimental set-up to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airBorne dust concentration considerably. As a basis for developing methods to eliminate dust related problems in rooms, there is a...

  12. NURE uranium deposit model studies

    International Nuclear Information System (INIS)

    The National Uranium Resource Evaluation (NURE) Program has sponsored uranium deposit model studies by Bendix Field Engineering Corporation (Bendix), the US Geological Survey (USGS), and numerous subcontractors. This paper deals only with models from the following six reports prepared by Samuel S. Adams and Associates: GJBX-1(81) - Geology and Recognition Criteria for Roll-Type Uranium Deposits in Continental Sandstones; GJBX-2(81) - Geology and Recognition Criteria for Uraniferous Humate Deposits, Grants Uranium Region, New Mexico; GJBX-3(81) - Geology and Recognition Criteria for Uranium Deposits of the Quartz-Pebble Conglomerate Type; GJBX-4(81) - Geology and Recognition Criteria for Sandstone Uranium Deposits in Mixed Fluvial-Shallow Marine Sedimentary Sequences, South Texas; GJBX-5(81) - Geology and Recognition Criteria for Veinlike Uranium Deposits of the Lower to Middle Proterozoic Unconformity and Strata-Related Types; GJBX-6(81) - Geology and Recognition Criteria for Sandstone Uranium Deposits of the Salt Wash Type, Colorado Plateau Province. A unique feature of these models is the development of recognition criteria in a systematic fashion, with a method for quantifying the various items. The recognition-criteria networks are used in this paper to illustrate the various types of deposits

  13. Laser deposition of HTSC films

    International Nuclear Information System (INIS)

    Studies of the high-temperature superconducting (HTSC) films fabrication by the laser deposition are reviewed. Physical and chemical processes taking place during laser deposition are considered, such as the target evaporation, the material transport from the target to the substrate, the film growth on the substrate, thermochemical reactions and mass transfer within the HTSC films and their stability. The experimental results on the laser deposition of different HTSC ceramics and their properties investigations are given. The major technological issues are discussed including the deposition schemes, the oxygen supply, the target compositions and structure, the substrates and interface layers selection, the deposition regimes and their impact on the HTSC films properties. 169 refs.; 6 figs.; 2 tabs

  14. Characteristics and potential forecast of ultramafic magmatite type Poyi Cu-Ni deposit in Ruoqiang of Xinjiang%新疆若羌县坡一超镁铁岩浆岩型铜镍矿床特征及远景展望

    Institute of Scientific and Technical Information of China (English)

    卢鸿飞; 王恒; 王鹏; 邓刚

    2016-01-01

    A large number of outcropped mafic-ultramafic rocks exist in Beishan rift valley zone of Xinjiang, and Poyi Cu-Ni deposit is located at the western part of Beishan rift valley Au-Cu-Ni metallogenic belt and the southwestern part of Pobei mafic-ultramafic rock belt.According to the ongoing exploration in this area from 1 989 to 2014,the scale of Poyi Cu-Ni deposit in Pobei rock belt is up to above 1 million tons.Based on previous works of predecessors,and combined with the diagenetic model in the environment of rift valley, this paper analyzed the mineralization environment of Poyi Cu-Ni deposit and evolution characteristics of mine-ralization,and it also set up a unique multi-phase magmatic mineralization model and summarized some clues for prospecting.The author established a metallogenic model for mafic-ultramafic magma sulfide type Cu-Ni deposit in the metallogenic belt,and put forward the prospecting prospect.%新疆北山裂谷带中出露有数量众多的镁铁-超镁铁岩,坡一铜镍矿位于北山裂谷金铜镍成矿带西部、坡北镁铁-超镁铁岩带西南部。经1989~2014年的持续勘查,坡北岩带中的坡一铜镍矿规模达到100万吨以上。笔者在前人工作的基础上,结合裂谷环境下成岩机制,分析了坡一铜镍矿成矿环境及成矿作用演化特征,树立了独特的多期岩浆成矿模式,建立了找矿标志,为成矿带镁铁-超镁铁岩浆硫化物型铜镍矿床建立了成矿模型,且对成矿远景做了探讨。

  15. Atomic-scale simulation of screw dislocation/coherent twin boundary interaction in Al, Au, Cu and Ni

    Energy Technology Data Exchange (ETDEWEB)

    Chassagne, M. [CEMES, CNRS, 29 rue Jeanne Marvig, 31055 Toulouse (France); SIMAP-GPM2, Grenoble INP, CNRS/UJF, 101 rue de la Physique, BP 46, 38402 Saint Martin d' Heres (France); Legros, M. [CEMES, CNRS, 29 rue Jeanne Marvig, 31055 Toulouse (France); Rodney, D., E-mail: david.rodney@grenoble-inp.fr [SIMAP-GPM2, Grenoble INP, CNRS/UJF, 101 rue de la Physique, BP 46, 38402 Saint Martin d' Heres (France)

    2011-02-15

    The influence of material and choice of interatomic potential on the interaction between an a/2<1 1 0>{l_brace}1 1 1{r_brace} screw dislocation and a {Sigma}3{l_brace}1 1 1{r_brace}<1 1 0> coherent twin boundary (CTB) is determined by simulating this process in a range of face-centered cubic metals modeled with a total of 10 embedded-atom method (EAM) potentials. Generalized stacking fault energies are computed, showing a linear relation between the stacking faut ({gamma}{sub S}) and twin energies, as well as between the unstable stacking fault ({gamma}{sub US}) and unstable twinning ({gamma}{sub UT}) energies. We show that the reaction mechanism (absorption of the dislocation into the CTB or transmission into the twinned region) and reaction stress depend strongly on the potential used, even for a given material and are controlled by the material parameter {gamma}{sub S}/{mu}b{sub P} (where {mu} is the shear modulus and b{sub P} the Shockley partial Burgers vector), rather than the sign of the ratio ({gamma}{sub US} - {gamma}{sub S})/({gamma}{sub UT} - {gamma}{sub S}), as proposed recently by Jin et al. . Moreover, there exists a critical reaction stress, close to 400 MPa, independent of the potential, below which the dislocation is absorbed in the CTB and above which the dislocation is transmitted into the twinned region. The simulations are discussed with respect to in situ transmission electron microscopy straining experiments in Cu that highlight the importance of thermally activated cross-slip in the interaction process and show that transmission across a twin boundary is possible but is most likely an indirect process.

  16. Effect Of Changing Laser Irradiance On The Laser Induced Plasma Parameters For Au/Cu Layered Target

    International Nuclear Information System (INIS)

    Pulsed laser induced plasma (LIP) has a very short temporal existence. Due to the transient nature of the produced LIP, with a fast evolution of its characteristic parameters, these parameters are heavily dependent on the irradiation conditions such as incident laser intensity, irradiation spot size, ambient gas composition and pressure. It is also true that these parameters vary drastically with axial or radial distance from the target surface under the same irradiation. In the present work depth profiling measurements of gold film onto copper substrate have been performed and the effect of changing laser irradiance by changing the working distance on both electron density and electron temperature has been also studied.

  17. Initial state geometry and fluctuations in Au+Au, Cu+Au and U+U collisions at RHIC

    CERN Document Server

    Schenke, Bjoern; Venugopalan, Raju

    2014-01-01

    We study within the IP-Glasma and two-component MC-Glauber models the effects of initial state geometry and fluctuations on multiplicities and eccentricities for several collision species at the Relativistic Heavy Ion Collider (RHIC). These include copper-gold (Cu+Au), gold-gold (Au+Au), and uranium-uranium (U+U) collisions. The multiplicity densities per participant pair are very similar in all systems studied. Ellipticities vary strongly between collision systems, most significantly for central collisions, while fluctuation driven odd moments vary little between systems. Event-by-event distributions of eccentricities in mid-central collisions are wider in Cu+Au relative to Au+Au and U+U systems. An anti-correlation between multiplicity and eccentricity is observed in ultra central U+U collisions which is weaker in the IP-Glasma model than the two-component MC-Glauber model. In ultra central Au+Au collisions the two models predict opposite signs for the slope of this correlation. Measurements of elliptic flo...

  18. Initial state geometry and fluctuations in Au+Au, Cu+Au and U+U collisions at RHIC

    OpenAIRE

    Schenke, Bjoern; Tribedy, Prithwish; Venugopalan, Raju

    2014-01-01

    We study within the IP-Glasma and two-component MC-Glauber models the effects of initial state geometry and fluctuations on multiplicities and eccentricities for several collision species at the Relativistic Heavy Ion Collider (RHIC). These include copper-gold (Cu+Au), gold-gold (Au+Au), and uranium-uranium (U+U) collisions. The multiplicity densities per participant pair are very similar in all systems studied. Ellipticities vary strongly between collision systems, most significantly for cen...

  19. TULSA UNIVERSITY PARAFFIN DEPOSITION PROJECTS

    Energy Technology Data Exchange (ETDEWEB)

    Michael Volk; Cem Sarica

    2003-10-01

    As oil and gas production moves to deeper and colder water, subsea multiphase production systems become critical for economic feasibility. It will also become increasingly imperative to adequately identify the conditions for paraffin precipitation and predict paraffin deposition rates to optimize the design and operation of these multiphase production systems. Although several oil companies have paraffin deposition predictive capabilities for single-phase oil flow, these predictive capabilities are not suitable for the multiphase flow conditions encountered in most flowlines and wellbores. For deepwater applications in the Gulf of Mexico, it is likely that multiphase production streams consisting of crude oil, produced water and gas will be transported in a single multiphase pipeline to minimize capital cost and complexity at the mudline. Existing single-phase (crude oil) paraffin deposition predictive tools are clearly inadequate to accurately design these pipelines because they do not account for the second and third phases, namely, produced water and gas. The objective of this program is to utilize the current test facilities at The University of Tulsa, as well as member company expertise, to accomplish the following: enhance our understanding of paraffin deposition in single and two-phase (gas-oil) flows; conduct focused experiments to better understand various aspects of deposition physics; and, utilize knowledge gained from experimental modeling studies to enhance the computer programs developed in the previous JIP for predicting paraffin deposition in single and two-phase flow environments. These refined computer models will then be tested against field data from member company pipelines. The following deliverables are scheduled during the first three projects of the program: (1) Single-Phase Studies, with three different black oils, which will yield an enhanced computer code for predicting paraffin deposition in deepwater and surface pipelines. (2) Two

  20. Atmospheric deposition 2000. NOVA 2003; Atmosfaerisk deposition 2000. NOVA 2003

    Energy Technology Data Exchange (ETDEWEB)

    Ellermann, T.; Hertel, O.; Hovmand, M.F.; Kemp, K.; Skjoeth, C.A.

    2001-11-01

    This report presents measurements and calculations from the atmospheric part of NOVA 2003 and covers results for 2000. It summarises the main results concerning concentrations and depositions of nitrogen, phosphorus and sulphur compounds related to eutrophication and acidification. Depositions of atmospheric compounds to Danish marine waters as well as land surface are presented. Measurements: In 2000 the monitoring program consisted of eight stations where wet deposition of ammonium, nitrate, phosphate (semi quantitatively) and sulphate were measured using bulk precipitation samplers. Six of the stations had in addition measurements of atmospheric content of A, nitrogen, phosphorus, and sulphur compounds in gas and particulate phase carried out by use of filter pack samplers. Filters were analysed at the National Environmental Research Institute. Furthermore nitrogen dioxide were measured using nitrogen dioxide filter samplers and monitors. Model calculations: The measurements in the monitoring program were supplemented with model calculations of concentrations and depositions of nitrogen and sulphur compounds to Danish land surface, marine waters, fjords and bays using the ACDEP model (Atmospheric Chemistry and Deposition). The model is a so-called trajectory model and simulates the physical and chemical processes in the atmosphere using meteorological and emission data as input. The advantage of combining measurements with model calculations is that the strengths of both methods is obtained. Conclusions concerning: 1) actual concentration levels at the monitoring stations, 2) deposition at the monitoring stations, 3) seasonal variations and 4) long term trends in concentrations and depositions are mainly based on the direct measurements. These are furthermore used to validate the results of the model calculations. Calculations and conclusions concerning: 1) depositions to land surface and to the individual marine water, 2) contributions from different emission

  1. Reforming deposit insurance and FDICIA

    OpenAIRE

    Robert A. Eisenbeis; Larry D. Wall

    2002-01-01

    Current discussions about deposit insurance reform center on issues such as the size of insurance premiums, the size of the fund, and the size of the coverage limits-all issues that reflect a concern with how to allocate the losses arising from bank failures. The authors of this article argue that such issues, while important, do not affect the performance of the deposit insurance system nor should they be the focus of deposit insurance reform. They suggest that reform efforts should be direc...

  2. Particle deposition in ventilation ducts

    Energy Technology Data Exchange (ETDEWEB)

    Sippola, Mark R.

    2002-09-01

    Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 {micro}m were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on

  3. Plasma Deposition of Amorphous Silicon

    Science.gov (United States)

    Calcote, H. F.

    1982-01-01

    Strongly adhering films of silicon are deposited directly on such materials as Pyrex and Vycor (or equivalent materials) and aluminum by a non-equilibrium plasma jet. Amorphous silicon films are formed by decomposition of silicon tetrachloride or trichlorosilane in the plasma. Plasma-jet technique can also be used to deposit an adherent silicon film on aluminum from silane and to dope such films with phosphorus. Ability to deposit silicon films on such readily available, inexpensive substrates could eventually lead to lower cost photovoltaic cells.

  4. Acid Deposition Maps in Spain

    International Nuclear Information System (INIS)

    Animal and monthly deposition velocity and total sulfur deposition maps have been performed for the peninsular Spain for 1992 by using the inferential method. To do this, updated databases with high space and time resolution, for land uses (CORINE) and meteorological information from analysis modelling for the same year, have been utilized. The final result are deposition maps in a 5x5 Km2 grid which allow to assess the methodology used in Europe to obtain the maps of excedances over the critical loads of pollutants. (Author) 32 refs

  5. Geochemical characteristics of Au-Sb poly-metallic ore deposits in Tuoleshan area at middle of the North Qilianshan Mountains and the ore potential%青海省北祁连中段托勒山地区金锑等多金属矿地球化学特征及其找矿前景

    Institute of Scientific and Technical Information of China (English)

    邝建中; 杨钻云; 林秦安

    2013-01-01

    青海省北祁连中段托勒山地区金锑多金属矿属北祁连中段托勒山成矿带.岩石地球化学分析表明,岩石中金含量最高的为石英脉,其次是石英碳酸盐岩、二云石英片岩、玄武岩、橄榄岩、硅质白云岩和糜棱岩等,且与破碎蚀变带关系密切,地层岩性和次级断裂构造对于Au及各元素的富集(或成矿)起着重要作用;土壤地球化学测量共圈出土壤异常6个,各异常中Au,Cu,As,Sb元素异常套合性较好,各元素曲线在具有矿化蚀变的硅质白云岩中峰值相对其他岩性较大,且Au,As,Sb元素具有较强的相关性.从地质角度来看,区域上金多金属矿化主要与地层、断裂构造和侵入岩有关,而起决定作用的是火山活动及火山岩.测区充分具备这些条件的地区目前地表揭露能有良好的成矿显示,这些成矿有利区域,尤其是深部岩体接触边界附近是成矿的重点和金、铜、锑多金属矿前景突破的关键.%At middle of the North Qilianshan Mountains there is the Tuoleshan ore belt in which Au-Sb poly-metallic ore deposits occur. Petrochemistry shows that gold is highest in quartz vein, then quartz-carbonate rock, biotite-muscovite quartz schist, basalt, peridotite, siliceous dolomite and myllonite etc. Concentration of gold is closely related to altered cataclastic rock zone. Lithology and sub-fractures play important role in enrichment of Au and ore elements. Soil geochemical survey shows 6 anomlies and Au, Cu,As,Sb element anomlies are well coincided. Peak value of each elements of altered, mineralized siliceous dolomite is higher than other lithologies and Au, As,Sb highly correlated. Geologically, the regional poly-metallic mineralization is related to strata and fractures and volcanism and volcanic rocks play important role in mineralization. In the survey area some localities possess such conditions with well revealed ore indication. In the favorable mineralization localities

  6. Ferroelectric thin films deposited by pulsed laser deposition

    Science.gov (United States)

    Dinu, Raluca; Vrejoiu, I.; Verardi, P.; Craciun, F.; Dinescu, Maria

    2001-06-01

    Influence of substrate and electrode on the properties of PbZr0.53Ti0.47O3 (PZT) thin films grown by pulsed laser deposition technique (1060 nm wavelength Nd:YAG laser light, 10 ns pulse duration, 10 Hz repetition rate, 0.35 J/pulse, 25 J/cm2 laser fluence, deposition rate about 1 angstrom/pulse) was studied. The substrate temperatures were in the range 380 degree(s)C-400 degree(s)C. Oriented crystalline PZT layers with 1-3 micrometers thickness were deposited on glass substrates plated with Au/Pt/NiCr electrodes, from a PZT commercial target in oxygen reactive atmosphere. The deposited PZT films with perovskite structure were preferentially oriented along the (111) direction as revealed from XRD spectra. Piezoelectric d33 coefficients up to 30 pC/N were obtained on as deposited films. Ferroelectric hysteresis loops at 100 Hz revealed a remanent polarization of 15 (mu) C/cm2 and a coercive field of 100 kV/cm. A comparison with properties of PZT films deposited using a KrF laser and with SrBi2Ta2O9 (SBT) films is reported.

  7. Cathodoluminescence in Quaternary carbonate deposits

    Science.gov (United States)

    Braithwaite, Colin J. R.

    2016-05-01

    The cathodoluminescent oscillatory and sectoral growth zones common in crystals formed in ancient limestone successions in a variety of putative environments appear to be rare or absent from Recent and Pleistocene marine carbonate sequences. The factors controlling cathodoluminescence and reasons for this disparity are examined. The cathodoluminescent zones in the cements of ancient rocks have been interpreted as responses to variations in the redox potential of formative pore waters during crystal growth; although similar cathodoluminescent behaviour is recorded from some deposits, including travertines and Quaternary speleothems, formed in what are thought to have been strongly oxidizing environments. The apparent absence of cathodoluminescence in the most Recent and Pleistocene marine deposits, that presumably reflect deposition and diagenesis in environments that are also characteristically oxidized, therefore seems anomalous. The controlling influences on cathodoluminescence are reviewed, together with evidence relating to observations of Pleistocene marine deposits and likely conditions of formation but, where it is present, the mechanism(s) for its development remain elusive.

  8. Hereditary iron and copper deposition

    DEFF Research Database (Denmark)

    Aaseth, Jan; Flaten, Trond Peder; Andersen, Ole

    2007-01-01

    Hereditary deposition of iron (primary haemochromatosis) or copper (Wilson's disease) are autosomal recessive metabolic disease characterized by progressive liver pathology and subsequent involvement of various other organs. The prevalence of primary haemochromatosis is approximately 0.5%, about...

  9. Gasoline from Kumkol deposit petroleum

    International Nuclear Information System (INIS)

    Samples of gasoline from petroleum of Kumkol deposit are investigated by chromatographic analysis. It is found, that gasoline is characterizing by increased content of iso-paraffin hydrocarbons. (author)

  10. Composition for preventing salt depositing

    Energy Technology Data Exchange (ETDEWEB)

    Mikhaylov, S.A.; Balakin, V.M.; Lezhenin, V.V.; Litvinets, Yu.I.; Marinin, N.S.; Talankin, V.S.; Yaryshev, G.M.

    1982-01-01

    A composition is proposed for preventing salt depositing which includes polyethylene-polyamine-N-methyl phosphonic acid or its salt and water. It is distinguished by the fact that in order to improve the degree of prevention of the salt depositing under low temperature conditions, it additionally contains ethylene glycol with the following ratio of components (% by mass): polyethylene polyamine-N-methylphosphonic acid or its salt 5-12; ethylene glycol 30-50; water--the rest.

  11. Uranium deposits in volcanic rocks

    International Nuclear Information System (INIS)

    Twenty-eight papers were presented at the meeting and two additional papers were provided. Three panels were organized to consider the specific aspects of the genesis of uranium deposits in volcanic rocks, recognition criteria for the characterization of such deposits, and approaches to exploration. The papers presented and the findings of the panels are included in the Proceedings. Separate abstracts were prepared for each of these papers

  12. Vapor deposition of hardened niobium

    Science.gov (United States)

    Blocher, Jr., John M.; Veigel, Neil D.; Landrigan, Richard B.

    1983-04-19

    A method of coating ceramic nuclear fuel particles containing a major amount of an actinide ceramic in which the particles are placed in a fluidized bed maintained at ca. 800.degree. to ca. 900.degree. C., and niobium pentachloride vapor and carbon tetrachloride vapor are led into the bed, whereby niobium metal is deposited on the particles and carbon is deposited interstitially within the niobium. Coating apparatus used in the method is also disclosed.

  13. Felsic magmatism and uranium deposits

    International Nuclear Information System (INIS)

    The strongly incompatible behaviour of uranium in silicate magmas results in its concentration in the most felsic melts and a prevalence of granites and rhyolites as primary U sources for the formation of U deposits. Despite its incompatible behavior, U deposits resulting directly from magmatic processes are quite rare. In most deposits, U is mobilized by hydrothermal fluids or ground water well after the emplacement of the igneous rocks. Of the broad range of granite types, only a few have U contents and physico-chemical properties that permit the crystallization of accessory minerals from which uranium can be leached for the formation of U deposits. The first granites on Earth, which crystallized uraninite, dated at 3.1 Ga, are the potassic granites from the Kaapval craton (South Africa) which were also the source of the detrital uraninite for the Dominion Reef and Witwatersrand quartz pebble conglomerate deposits. Four types of granites or rhyolites can be sufficiently enriched in U to represent a significant source for the genesis of U deposits: per-alkaline, high-K met-aluminous calc-alkaline, L-type peraluminous and anatectic pegmatoids. L-type peraluminous plutonic rocks in which U is dominantly hosted in uraninite or in the glass of their volcanic equivalents represent the best U source. Per-alkaline granites or syenites are associated with the only magmatic U-deposits formed by extreme fractional crystallization. The refractory character of the U-bearing minerals does not permit their extraction under the present economic conditions and make them unfavorable U sources for other deposit types. By contrast, felsic per-alkaline volcanic rocks, in which U is dominantly hosted in the glassy matrix, represent an excellent source for many deposit types. High-K calc-alkaline plutonic rocks only represent a significant U source when the U-bearing accessory minerals (U-thorite, allanite, Nb oxides) become metamict. The volcanic rocks of the same geochemistry may be

  14. [Calcium pyrophosphate dihydrate deposition disease].

    Science.gov (United States)

    Koitschev, C; Kaiserling, E; Koitschev, A

    2003-08-01

    Calcium pyrophosphate dihydrate deposition disease (CPPD) of the temporomandibular joint is rare. The disorder is characterized by the presence of crystal deposits within the affected joint. The deposition of crystals in adjacent soft tissue may lead to the formation of pseudotumors. This form of the disease is called tophaceous pseudogout and typically affects the temporomandibular joint. It is difficult to differentiate the disease, particularly from malignant tumors, on the clinical and radiographic findings alone. The diagnosis is based on histological identification of the calcium pyrophosphate crystals. We present an unusually advanced case of tophaceous pseudogout of the temporomandibular joint. The etiology, clinical and diagnostic criteria as well as treatment options are discussed on the basis of our own experience and a review of the literature. PMID:12942180

  15. Kalan uranium deposit profitability expectation

    International Nuclear Information System (INIS)

    The aims of this paper were to reevaluate the chance for uranium deposit at Kalan to be profitable to mine. For that reasons, it is necessary to calculate not only the expenses, but also to give and estimation of the value of the uranium to be produced. Mining and milling considerations had been made for Eko-Hi tam and Rirang-Tanah Merah deposits. It is sugested that feasibility study is needed for determination of the most suitable mining method to be applied for those deposits. It was also suggested that an upgrade of milling feed is needed for ore processing. The use of Knelson concentrator was introduced for ore sorting. (author); 4 refs; 3 figs

  16. A Radon Progeny Deposition Model

    CERN Document Server

    Guiseppe, V E; Hime, A; Rielage, K; Westerdale, S

    2011-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly Rn-222) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of Pb-210 on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to depos...

  17. Sub-aerial tailings deposition

    International Nuclear Information System (INIS)

    The sub-aerial technique involves the systematic deposition of tailings in thin layers and allowing each layer to settle, drain and partially air dry prior to covering with a further layer. Underdrainage produces densities in excess of those achieved by sub-aqueous deposition and any air-drying serves to preconsolidate each layer with a resulting further increase in density. The low permeability of the tailings surface resulting from this deposition technique results in high runoff coefficients and, by decanting the runoff component of direct precipitation, a net evaporation condition can be achieved even in high rainfall areas. An underdrainage system prevents the build-up of excess pore-pressures within the tailings mass and at decommissioning the tailings are fully consolidated and drained thereby eliminating the possibility of any long term seepage. This paper presents a general description of these design concepts, and details of two projects where the concepts have been applied

  18. TULSA UNIVERSITY PARAFFIN DEPOSITION PROJECTS

    Energy Technology Data Exchange (ETDEWEB)

    Cem Sarica; Michael Volk

    2004-06-01

    As oil and gas production moves to deeper and colder water, subsea multiphase production systems become critical for economic feasibility. It will also become increasingly imperative to adequately identify the conditions for paraffin precipitation and predict paraffin deposition rates to optimize the design and operation of these multi-phase production systems. Although several oil companies have paraffin deposition predictive capabilities for single-phase oil flow, these predictive capabilities are not suitable for the multiphase flow conditions encountered in most flowlines and wellbores. For deepwater applications in the Gulf of Mexico, it is likely that multiphase production streams consisting of crude oil, produced water and gas will be transported in a single multiphase pipeline to minimize capital cost and complexity at the mudline. Existing single-phase (crude oil) paraffin deposition predictive tools are clearly inadequate to accurately design these pipelines, because they do not account for the second and third phases, namely, produced water and gas. The objective of this program is to utilize the current test facilities at The University of Tulsa, as well as member company expertise, to accomplish the following: enhance our understanding of paraffin deposition in single and two-phase (gas-oil) flows; conduct focused experiments to better understand various aspects of deposition physics; and, utilize knowledge gained from experimental modeling studies to enhance the computer programs developed in the previous JIP for predicting paraffin deposition in single and two-phase flow environments. These refined computer models will then be tested against field data from member company pipelines.

  19. 78 FR 56583 - Deposit Insurance Regulations; Definition of Insured Deposit

    Science.gov (United States)

    2013-09-13

    ... exposure, but argued that it would adversely affect public relations. The commenter suggested that foreign... changes. \\15\\ 78 FR 11604 (February 19, 2013). II. Statutory Framework A. Definition of ``Insured Deposit....C. 1820(g); see, e.g., Unlimited Coverage for Noninterest- Bearing Transaction Accounts, 75 FR...

  20. Nanofriction properties of molecular deposition films

    Institute of Scientific and Technical Information of China (English)

    王强斌; 高芒来; 张嗣伟

    2000-01-01

    The nanofriction properties of Au substrate and monolayer molecular deposition film and multilayer molecular deposition films on Au substrate and the molecular deposition films modified with alkyl-terminal molecule have been investigated by using an atomic force microscope. It is concluded that ( i ) the deposition of molecular deposition films on Au substrate and the modification of alkyl-terminal molecule to the molecular deposition films can reduce the frictional force; (ii) the molecular deposition films with the same terminal exhibit similar nanofriction properties, which has nothing to do with the molecular chain-length and the layer number; (iii) the unstable nanofriction properties of molecular deposition films are contributed to the active terminal of the molecular deposition film, which can be eliminated by decorating the active molecular deposition film with alkyl-terminal molecule, moreover, the decoration of alkyl-terminal molecule can lower the frictional force conspicuously; (iv) the relat

  1. Tumoral calcium pyrophosphate deposition disease

    International Nuclear Information System (INIS)

    A report of two patients in which a soft tissue mass, initially regarded as a malignant tumor, was shown to be the result of calcium pyrophosphate deposition disease. The first case, a woman aged 71 years, presented with a mass involving the right fifth finger. In the second case, also a women aged 71 years, the lesion involved the tissues adjacent to the right hip. Each lesion consisted of a mass of highly cellular tissue containing deposits of calcium pyrophosphate dihydrate crystals. The clinical, radiological, and pathological features of the two cases are compared with those of seven similar cases reported in the literature. (orig.)

  2. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    Sandstone deposits represent a large part of the world's uranium deposits, and are particularly common in the United States of America. Orebodies of this type tend to exhibit many of the following features: (1) tabular or roll shape; (2) cross-bedded grey or green sandstone host rock, generally of Silurian or younger age; (3) a certain minimum thickness of sandstone; (4) mudstone interbedded with the sandstone; and (5) abundant organic matter and pyrite. The orebodies contain mainly uraninite and coffinite, with carnotite and other secondary minerals, and are commonly clustered along mineral trends. (author)

  3. Deposition of diamondlike carbon films

    Science.gov (United States)

    Mirtich, M. J.; Sovey, J. S.; Banks, B. A. (Inventor)

    1984-01-01

    A diamondlike carbon film is deposited in the surface of a substrate by exposing the surface to an argon ion beam containing a hydrocarbon. The current density in the ion beam is low during initial deposition of the film. Subsequent to this initial low current condition, the ion beam is increased to full power. At the same time, a second argon ion beam is directed toward the surface of the substrate. The second ion beam has an energy level much greater than that of the ion beam containing the hydrocarbon. This addition of energy to the system increases mobility of the condensing atoms and serves to remove lesser bound atoms.

  4. Advanced deposition model for thermal activated chemical vapor deposition

    Science.gov (United States)

    Cai, Dang

    Thermal Activated Chemical Vapor Deposition (TACVD) is defined as the formation of a stable solid product on a heated substrate surface from chemical reactions and/or dissociation of gaseous reactants in an activated environment. It has become an essential process for producing solid film, bulk material, coating, fibers, powders and monolithic components. Global market of CVD products has reached multi billions dollars for each year. In the recent years CVD process has been extensively used to manufacture semiconductors and other electronic components such as polysilicon, AlN and GaN. Extensive research effort has been directed to improve deposition quality and throughput. To obtain fast and high quality deposition, operational conditions such as temperature, pressure, fluid velocity and species concentration and geometry conditions such as source-substrate distance need to be well controlled in a CVD system. This thesis will focus on design of CVD processes through understanding the transport and reaction phenomena in the growth reactor. Since the in situ monitor is almost impossible for CVD reactor, many industrial resources have been expended to determine the optimum design by semi-empirical methods and trial-and-error procedures. This approach has allowed the achievement of improvements in the deposition sequence, but begins to show its limitations, as this method cannot always fulfill the more and more stringent specifications of the industry. To resolve this problem, numerical simulation is widely used in studying the growth techniques. The difficulty of numerical simulation of TACVD crystal growth process lies in the simulation of gas phase and surface reactions, especially the latter one, due to the fact that very limited kinetic information is available in the open literature. In this thesis, an advanced deposition model was developed to study the multi-component fluid flow, homogeneous gas phase reactions inside the reactor chamber, heterogeneous surface

  5. Electro-spark deposition technology

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.N. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-12-01

    Electro-Spark Deposition (ESD) is a micro-welding process that uses short duration, high-current electrical pulses to deposit or alloy a consumable electrode material onto a metallic substrate. The ESD process was developed to produce coatings for use in severe environments where most other coatings fail. Because of the exceptional damage resistance of these coatings, and the versatility of the process to apply a wide variety of alloys, intermetallics, and cermets to metal surfaces, the ESD process has been designated critical to the life and economy of the advanced fossil energy systems as the higher temperatures and corrosive environments exceed the limits of known structural materials to accommodate the service conditions. Developments include producing iron aluminide-based coatings with triple the corrosion resistance of the best previous Fe{sub 3}Al coatings, coatings with refractory metal diffusion barriers and multi layer coatings for achieving functionally gradient properties between the substrate and the surface. A new development is the demonstration of advanced aluminide-based ESD coatings for erosion and wear applications. One of the most significant breakthroughs to occur in the last dozen years is the discovery of a process regime that yields an order of magnitude increase in deposition rates and achievable coating thicknesses. Achieving this regime has required the development of advanced ESD electronic capabilities. Development is now focused on further improvements in deposition rates, system reliability when operating at process extremes, and economic competitiveness.

  6. Large cooling tower drift deposition

    International Nuclear Information System (INIS)

    A model for the determination of drift deposition around natural-draft cooling towers is presented. An application of the model in actual operating conditions indicates the effect of drift rate at the cooling tower outlet and weather conditions on the size and shape of wetted area. (author)

  7. Simple Chemical Vapor Deposition Experiment

    Science.gov (United States)

    Pedersen, Henrik

    2014-01-01

    Chemical vapor deposition (CVD) is a process commonly used for the synthesis of thin films for several important technological applications, for example, microelectronics, hard coatings, and smart windows. Unfortunately, the complexity and prohibitive cost of CVD equipment makes it seldom available for undergraduate chemistry students. Here, a…

  8. ECONOMIC GEOLOGY (2)NONMETALS DEPOSITS

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>20082329 Chen Wang(China University of Geosciences,Beijing 100083,China) Control Factors on Distribution of Carboniferous Bauxite Deposits in Western Henan Province (Geotectonica et Metallogenia,ISSN1001—1552,CN44—1595/P,31(4),2007,p.452—456,1 illus.,10 refs.) Key words:bauxite,mineralization con- trols,Henan Province

  9. The uranium deposits of Ontario

    International Nuclear Information System (INIS)

    The principal types of uranium deposits in Ontario are carbonatites and fenites, alkalic volcanic rocks, pegiatites, calc-silicate rocks, pyritic quartz-pebble conglomerates, polymictic conglomerates and some pelitic rocks, and various 'pitchblende' deposits including late Precambrian unconformities, possibly late Precambrian diabase dikes, and other unconformities: carbonates, sandstones, lignites, and semi-pelitic rocks of middle and upper Precambrian age. Only red unzoned pegmatite and the pyritic quartz-pebble conglomerate have supported production. Ontario reasonably assured and estimated resources in the economic and subeconomic categories in 1977 amounted to 553 000 tonnes U, and 1977 production was 4000 tonnes U. Measured, indicated, and inferred resources in the Elliot Lake - Agnew Lake area are at least 400 000 tonnes U. The latter deposits are also a significant thorium resource. Geological features reflecting major changes in physics and chemistry are prime controls on distribution of uranium deposits. Geological province and subprovince boundaries, major faults, higher metamorphic grades, domain boundaries related to quartz monzonite batholiths, alkalic complexes, and the distribution of carbonate rocks are examples of such geological features

  10. Deposition and Resuspension of Particles

    DEFF Research Database (Denmark)

    Lengweiler, P.; Nielsen, Peter V.; Moser, A.;

    To investigate the physical process of deposition and resuspension of particles in the indoor environment, scale experiments are used and a sampling method is established. The influences of surface orientation and turbulence and velocity of the air on the dust load on a surface are analysed....

  11. Investigation on the age of mineralization in the Sungun porphyry Cu-Mo deposit, NW Iran with a regional metallogenic perspective

    Science.gov (United States)

    Simmonds, Vartan; Moazzen, Mohssen; Mathur, Ryan

    2016-04-01

    The Sungun porphyry copper deposit (PCD) is located in NW Iran, neighbouring several other PCDs and prospects in the region and the Lesser Caucasus (south Armenia). It lies on the Urumieh-Dokhtar magmatic arc (UDMA), which formed through the northeast-ward subduction of the Neo-Tethyan oceanic crust beneath the Central Iranian plate during late-Mesozoic and early-Cenozoic [1], and hosts the porphyry copper metallogenic belt of Iran. The Sungun PCD is the second largest deposit in Iran with ore reserves of about 850 Mt at 0.62 wt% Cu and 0.01 wt% Mo and probable reserves over 1Gt. The monzonitic to quartz monzonitic porphyry stock intruded the upper Cretaceous carbonates and Eocene volcano-sedimentary rocks. It produced a skarn-type mineralization at its contact zone with the carbonate rocks, as well as vast hydrothermal alteration zones and porphyry-type Cu and Mo mineralization. The zircon U-Pb age of the host porphyry stock is about 22.5±0.4 to 20.1±0.4 Ma [2]. Re-Os dating of four molybdenite separates from this PCD shows ages ranging between 22.9±0.2 to 21.7±0.2 Ma, with an average of 22.57±0.2 Ma, corresponding to the early Miocene (Aquitanian). These ages indicate that both the porphyry stock and the Cu-Mo mineralization are post-collisional events, similar to many other deposits and prospects in NW and central Iran and south Armenia, and the mineralization occurred shortly after the emplacement of the host stock, corresponding better to the ages obtained from the marginal parts of the stock. Magmatism and mineralization in Sungun coincides with the third metallogenic epoch in the Lesser Caucasus (Eocene to Miocene; [3]), though it is considerably younger than all of the dated PCDs and prospects in the south Armenia. It also postdates Cu-Mo mineralizations in the Saheb Divan (35 Ma), Qaradagh batholith (31.22±0.28 to 25.19±0.19 Ma), as well as Haft Cheshmeh PCD (28.18±0.42 to 27.05±0.37 Ma) in NW Iran, while it seems to be coeval with the Kighal

  12. 西藏洞中松多铅锌多金属矿床地质特征及成因%A preliminary study of the geologic characteristics and genesis of the Dongzhongsongduo lead-zinc polymetallic deposit, Tibet

    Institute of Scientific and Technical Information of China (English)

    辛存林; 都卫东; 张育平; 魏明; 陈世伟

    2013-01-01

    The Dongzhongsongduo lead-zinc polymetallic deposit is located in the east part of the eastern Gangdese polymetallic mineralization belt. The ore body has mainly occurred as strumiform and stratoid structures in the carbonatite within the skarns of the pre-Ordovician Songduo group complex and the mid-permian Luobadui formation. Wall rock is made up of carbonatite and has strongly altered. Two alterations and nine main ore zones have been delineated. Lead and zinc are the main useful elements in the ore, and silver, iron, copper, sulfur as beneficial groups in the ore. The length of the layered ore-bodies is between 2 620 and 4 100 m, 50∼150 m and the thickness is between the Songduo group complex and the Luobadui formation. The ore is 120∼2 881 m long and 2.1∼13.1 m thick. The footwall of the ore are limestone and tuff and the hanging wall is crystal tuff. The ore minerals include pyrrhotine, pyrite, chalcopyrite, galena and sphalerite, etc. The gangue minerals include quartz, diopside, garnet, chlorite, epidote, calcite and feldspar, etc. The mineralization of lead and zinc was closely related to magmatic activity and meteoric, especially related to the magmatic hydrothermalism which had intruded into carbonatite in the period of late Yanshan-early Himalayas. Presumably, the formation of lead and zinc deposit has been related closely to the plate collision of the Indian-Eurasian Plate and the uplift zone in the Tibetan Plateau. This is the first study of the causes of the deposit. Through an analysis and discussion of the geological characteristics and metallogenic source materials, we believe that the Dongzhongsongduo lead-zinc polymetallic deposit has been related to the tectonic and magmatic activities. The structure has provided motive channels and accumulated space for the deposit. And the deep magma of late Yanshan period-early Himalayas has provided the main ore-forming materials and energy for the deposit. Therefore, it is considered that the

  13. Vapor deposition of tantalum and tantalum compounds

    International Nuclear Information System (INIS)

    Tantalum, and many of its compounds, can be deposited as coatings with techniques ranging from pure, thermal chemical vapor deposition to pure physical vapor deposition. This review concentrates on chemical vapor deposition techniques. The paper takes a historical approach. The authors review classical, metal halide-based techniques and current techniques for tantalum chemical vapor deposition. The advantages and limitations of the techniques will be compared. The need for new lower temperature processes and hence new precursor chemicals will be examined and explained. In the last section, they add some speculation as to possible new, low-temperature precursors for tantalum chemical vapor deposition

  14. Computational study of wax deposition in pipeline

    Science.gov (United States)

    Duan, Jimiao; Gong, Jing; Liu, Huishu

    2013-07-01

    Wax deposition in subsea pipelines is one of the flow assurance problems for oil and gas production. In contrast to many studies about single phase wax deposition, gas-oil wax deposition studies are very limited. The wax deposition mechanism and model prediction are restricted by many factors such as hydrodynamic and thermal when multiphase flow is involved. Wax deposition modeling becomes complicated under multiphase flowing conditions. wax deposition is depended by the flow pattern. The stratified flow is one of the most common flow patterns in the actual subsea gas-oil flowing conditions. In this work, numerical methods are used to study wax deposition in oil-gas stratified flow through a pipe. Based on the flow analysis about stratified flow, the non-isothermal heat and mass transfer is calculated. The temperature profile of the oil and the concentration profile of wax in oil are obtained. The change of the oil-gas interface i.e. the liquid holdup throughout the pipe must be taken into the heat and mass balance. The valid wax deposition surface must be taken into the wax deposition modeling by establishing function of the liquid holdup and the wetted area by oil. The molecular diffusion is as the deposition mechanism. The increase of the wax fraction in the deposit as a function of time depends on the mass flux from the oil deposit interface into the gel and the growth of the deposit thickness depends on the difference between the mass flux from the bulk oil to the oil deposit interface and the mass flux from the interface into the deposit. In addition, the growth of the wax deposit as a function of time along with the effect oil flow rate, gas flow rate and the inlet temperature are discussed. The presence of gas significantly reduces the severity of wax deposition by altering the heat and mass transfer characteristics.

  15. An exploration model for Jiama copper polymetallic deposit in Maizhokunggar County, Tibet%西藏墨竹工卡县甲玛铜多金属矿床勘查模型

    Institute of Scientific and Technical Information of China (English)

    唐菊兴; 唐晓倩; 钟裕峰; 彭慧娟; 邓世林; 郑文宝; 应立娟; 汪雄武; 钟康惠; 秦志鹏; 丁枫; 黎枫佶

    2011-01-01

    The Jiama copper polymetallic deposit in Tibet is a significant ore deposit serving as a nonferrous metal base in central Tibet.This paper deals emphatically with the ore bodies in such aspects as its metallogenic geological conditions, prospecting indicators, geochemical exploration model, geophysical exploration model and spatialframework.Studies show that the ore-controlling strata are sandy slate and hornfels of Linbuzong Formation (K1l) and marble and limestone of Duodigou Formation (J3d), and that hornfels controls the distribution of hornfels-type ore bodies, and inter-layer structure between hornfels and marble controls skarn-type ore bodies due to the good trap formed by the hornfels which caused good magrnatic hydrothermal mineralization.There are nine types of exposed magrnatic rocks, such as granite porphyry, biotite monzonite granite porphyry, granite diorite porphyrite, quartz diorite porphyry and diorite porphyryp.Granite of high-K calc-alkaline series is related to the passive filling of mineralization into the collapse space caused by the structure.The ore-forming structure is the Niumatang complex anticline in the center of the Jiama-Kajunguo nappe structure controlling the generation of skarn and porphyry type ore bodies.The geochemical exploration model at the scale of 1:10 000 indicates that Cu-Mo-Au-Ag-Bi-Sn, and Mo are concentrated in the anomaly center, Bi and Sn as the high temperature elements exist in the internal circle and As, Sb, Hg, Pb, Zn, Co and Ni as the lower temperature elements are present in the external circle.Co and Ni anomalies suggest that the original rocks were carbonaceous and argillaceous sandy slate, As, Sb and Hg anomalies imply the wide distribution of pyrite in hornfels and represent the external alteration of porphyry metallogenic system.Cu, Mo, Au, Ag, Sn and Bi assume “M"-shaped distribution along the cross section.The geophysical exploration model at the scale of 1:10 000 indicates that the high precision

  16. Atmosfærisk deposition

    DEFF Research Database (Denmark)

    Ellermann, T.; Hertel, O.; Kemp, K.;

    Kvælstofdepositionen til danske havområder, fjorde, vige og bugte er for 2001 blevet beregnet til 118 ktons N, hvilket er ca. 20 % lavere end i 2000. Tilsvarende er depositionen til landområderne beregnet til 87 ktons N, hvilket svarer til deposition i 2000. Den primære årsag til den højere...... deposition for 1999-2001, i forhold til tidligere år, er ændringer i beregningsmetoden. Den samlede kvælstofdeposition til farvandene er faldet svagt i perioden 1989-2001. Depositionen til landoverflader skønnes ikke ændret betydeligt. Depositionen af svovlforbindelser til danske landområder er for 2001...

  17. Electro-spark deposition technology

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.N. [Pacific Northwest Lab., WA (United States)

    1996-08-01

    Electro-Spark Deposition (ESD) is a micro-welding process that uses short duration, high-current electrical pulses to deposit or alloy a consumable electrode material onto a metallic substrate. The ESD process was developed to produce coatings for use in severe environments where most other coatings fail. Because of the exceptional damage resistance of these coatings, and the versatility of the process to apply a wide variety of alloys, intermetallics, and cermets to metal surfaces, the ESD process has been designated as one of the enabling technologies for advanced energy systems. Developments include producing iron aluminide-based coatings with triple the corrosion resistance of the best previous Fe{sub 3}Al coatings, coatings with refractory metal diffusion barriers and multi layer coatings for achieving functionally gradient properties between the substrate and the surface. One of the most significant breakthroughs to occur in the last dozen years is the discovery of a process regime that promises an order of magnitude increase in deposition rates and achievable coating thicknesses. Since this regime borders on and exceeds the normal operating limits of existing ESD electronic equipment, development is in progress to produce equipment that can consistently and reliably achieve these conditions for a broad range of materials. Progress so far has resulted in a consistent 500% increase in deposition rates, and greater rates still are anticipated. Technology transfer activities are a significant portion of the ESD program effort. Notable successes now include the start-up of a new business to commercialize the ESD technology, the incorporation of the process into the operations of a major gas turbine manufacturer, major new applications in gas turbine blade and steam turbine blade protection and repair, and in military, medical, metal-working, and recreational equipment applications.

  18. Complexing and hydrothermal ore deposition

    CERN Document Server

    Helgeson, Harold C

    1964-01-01

    Complexing and Hydrothermal Ore Deposition provides a synthesis of fact, theory, and interpretative speculation on hydrothermal ore-forming solutions. This book summarizes information and theory of the internal chemistry of aqueous electrolyte solutions accumulated in previous years. The scope of the discussion is limited to those aspects of particular interest to the geologist working on the problem of hydrothermal ore genesis. Wherever feasible, fundamental principles are reviewed. Portions of this text are devoted to calculations of specific hydrothermal equilibriums in multicompone

  19. Electrochemical Depositions in Ionic Liquids

    OpenAIRE

    De Vreese, Peter

    2013-01-01

    In this PhD thesis, several aspects of the electrodeposition of metals and alloys in ionic liquids were investigated. First, the deposition of brass from choline acetate was studied. Secondly, the electrodeposition of pure molybdenum from ionic liquids based on phosphonium chloride and zinc chloride was treated. In each case, the influence of water, either as a main constituent of the electrolyte or an impurity, was investigated. When comparing electrochemical processes such as electrodeposit...

  20. CTD_DATABASE - Cascadia tsunami deposit database

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Cascadia Tsunami Deposit Database contains data on the location and sedimentological properties of tsunami deposits found along the Cascadia margin. Data have...

  1. Are international deposits tax-driven?

    OpenAIRE

    Huizinga, H.P.; Nicodeme, G.

    2004-01-01

    This paper investigates the impact of tax policy on international depositing. Non-bank international deposits are shown to be positively related to interest income and wealth taxes and to the presence of domestic bank interest reporting. This suggests that international deposits are in part intended to facilitate tax evasion. The tax sensitivity of international deposits is estimated to be higher in 1999 than before. At present, only part of international interest flow are covered by either n...

  2. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao;

    2015-01-01

    This study investigates the shear adhesion strength of biomass ash deposits on superheater tubes. Artificial biomass ash deposits were prepared on superheater tubes and sintered in an oven at temperatures up to 1000°C. Subsequently, the deposits were sheared off with the help of an electrically...

  3. 75 FR 6348 - Deposit of Biological Materials

    Science.gov (United States)

    2010-02-09

    ... Patent and Trademark Office Deposit of Biological Materials ACTION: Proposed collection; comment request....Fawcett@uspto.gov . Include ``0651-0022 Deposit of Biological Materials comment'' in the subject line of....Hanlon@uspto.gov . SUPPLEMENTARY INFORMATION: I. Abstract The deposit of biological materials as part...

  4. Silicidation of Niobium Deposited on Silicon by Physical Vapor Deposition

    Energy Technology Data Exchange (ETDEWEB)

    Coumba Ndoye, Kandabara Tapily, Marius Orlowski, Helmut Baumgart, Diefeng Gu

    2011-07-01

    Niobium was deposited by physical vapor deposition (PVD) using e-beam evaporation on bare (100) silicon substrates and SiO2 surfaces. The formation of niobium silicide was investigated by annealing PVD Nb films in the temperatures range 400–1000°C. At all elevated annealing temperatures the resistivity of Nb silicide is substantially higher than that of Nb. The Nb silicidation as a function of temperature has been investigated and different NbXSiy compounds have been characterized. It has been observed that the annealing of the Nb film on Si is accompanied by a strong volume expansion of about 2.5 of the resulting reacted film. The films' structural properties were studied using X-Ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and atomic force microscopy (AFM), which was not previously presented in the context of the extant NbSi literature. The X-Ray diffraction characterization of the Nb on Si sample annealed at 1000°C, showed the presence of hexagonal Nb5Si3 phases, with a dominant peak at the (200) plane, and NbSi2 phases. Fractal dimension calculations indicate a distinct transition from Stranski-Krastanov to Volmer-Weber film growth for NbSi formation at the annealing temperature of 600°C and above.

  5. Deposition station for selenium isotopes

    International Nuclear Information System (INIS)

    Complete text of publication follows. Isotopic tracing of nanoparticles mostly involved in environmental and metabolic processes, industrial, and agricultural technologies, attracts an increasing attention nowadays. As an experimental goal, for proposed tracing studies selenium was chosen, which is an essential trace element for the nutrition of almost all living organisms, since it plays a crucial role in the antioxidant activity of seleno-enzymes. Selenium in forms of nanoparticles being synthesized by wet chemical or microbial dissimilatory processes, turned out to possess new functionality as examplified in affecting semiconductor properties, toxicity, and growth factors, which are important for both nutritional supplements and potential cancer therapy agents. Stable isotope tracing of selenium nanoparticles under in vivo conditions would then yield relevant information on biodistributions, efficiency and safety issues of applications. A prototype version of a deposition station for enrichment of stable selenium isotopes was constructed and installed downstream to the sector magnet of the DiSP isotope separator. The deposition of the isotopic beam particles was carried out with the use of selfsputtering technique. The beam with a kinetic energy of 25-30 keV was first guided through electrostatic elements, where it was focused and decelerated to 300-500 eV (Fig. 1). The geometry of the electrostatic lenses was designed with the simulation code SIMION 8. The outcoming beam impinged upon the surface of a tungsten disc, on which recombination and selfsputtering of selenium ions occurred. Sputtering yields and efficiencies were measured as a function of beam intensities. It was concluded that emission of the selenium atoms can be predominantly attributed to heat spike mechanism due to large differences in evaporation characteristics of selenium and tungsten. The selenium atoms were then deposited as a thin film on a polypropylene (PP) surface with a conical geometry

  6. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao;

    2016-01-01

    Ash deposition on boiler surfaces is a major problem encountered during biomass combustion. Ash deposition adversely influences the boiler efficiency, may corrode heat transfer surfaces, and may even completely block flue gas channels in severe cases, causing expensive unscheduled boiler shutdowns....... Therefore, timely removal of ash deposits is essential for optimal boiler operation. In order to improve the qualitative and quantitative understanding of deposit shedding in boilers, this study investigates the shear adhesion strength of biomass ash deposits on superheater tubes. Artificial biomass ash...

  7. Impulse Plasma Deposition (IPD) of Compound powder

    International Nuclear Information System (INIS)

    Different powder materials have been deposited by Impulse plasma Deposition(IPD) using coaxial plasma accelerator. Commercial compound powder is placed at the breach of the plasma accelerator. For discharge energy of 208 Joule, the deposited layer thickness was 3 nm/pulse. Analyses showed that the deposited layer consists of the different materials in the powder compound. Plasma current sheath carried the powder ions has been studied experimentally and theoretically. The grain size distribution for the deposited materials showed that most of the grain size is 2 um with Maxwellian distribution

  8. Towards a genetic classification of uranium deposits

    International Nuclear Information System (INIS)

    As the IAEA's uranium deposit classification is based on the deposit nature and morphology, some deposits which have been formed by very different genetic processes and located in very different geological environments, are grouped according to this classification. In order to build up a reliable genetic classification based on the mechanism at the origin of the formation of the deposit, the author presents the five main categories according to which uranium deposits can be classified: magmatic, hydrothermal, evapotranspiration, syn-sedimentary, and infiltration of meteoric water

  9. Particle deposition in granular media: Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Tien, Chi

    1987-01-01

    This paper discusses topics on particle deposition in granular media. The six topics discussed are: experimental determination of initial collection efficiency in granular beds - an assessment of the effect of instrument sensitivity and the extent of particle bounce-off; deposition of polydispersed aerosols in granular media; in situ observation of aerosol deposition in a two-dimensional model filter; solid velocity in cross-flow granular moving bed; aerosol deposition in granular moving bed; and aerosol deposition in a magnetically stabilized fluidized bed. (LSP)

  10. Minerals deposited as thin films

    International Nuclear Information System (INIS)

    Free matrix effects are due to thin film deposits. Thus, it was decided to investigate this technique as a possibility to use pure oxide of the desired element, extrapolating its concentration from analytical curves made with avoiding, at the same time, mathematical corrections. The proposed method was employed to determine iron and titanium concentrations in geological samples. The range studied was 0.1-5%m/m for titanium and 5-20%m/m for iron. For both elements the reproducibility was about 7% and differences between this method and other chemical determinations were 15% for titanium and 7% for iron. (Author)

  11. Metal deposition using seed layers

    Science.gov (United States)

    Feng, Hsein-Ping; Chen, Gang; Bo, Yu; Ren, Zhifeng; Chen, Shuo; Poudel, Bed

    2013-11-12

    Methods of forming a conductive metal layers on substrates are disclosed which employ a seed layer to enhance bonding, especially to smooth, low-roughness or hydrophobic substrates. In one aspect of the invention, the seed layer can be formed by applying nanoparticles onto a surface of the substrate; and the metallization is achieved by electroplating an electrically conducting metal onto the seed layer, whereby the nanoparticles serve as nucleation sites for metal deposition. In another approach, the seed layer can be formed by a self-assembling linker material, such as a sulfur-containing silane material.

  12. Valorization of small uranium deposits

    International Nuclear Information System (INIS)

    For the valorization of small uranium deposits, the Total Mining Co. has developed an original leaching process in immersed live stalls, allied to the treatment of uraniferous liquors on ion exchanger resins. This technology was put in operation at Saint-Pierre (Cantal) in 1976, at La Ribiere (Creuse) in 1982 and in Bertholene (Aveyron) in 1985. In the last mentioned installation, 75 t of uranium can be produced per year on the basis of 60 000 t of ore containing 1.5 kg of uranium per ton. The investments per kg of uranium have thus been reduced to a quarter of their value in a conventional plant

  13. Carbonate Deposition on Antarctic Shelves

    Science.gov (United States)

    Frank, T. D.; James, N. P.; Malcolm, I.

    2011-12-01

    Limestones associated with glaciomarine deposits occur throughout the geologic record but remain poorly understood. The best-described examples formed during major ice ages of the Neoproterozoic and Late Paleozoic. Quaternary analogs on Antarctic shelves have received comparatively little study. Here, we report on the composition, spatial distribution, and stratigraphic context of carbonate sediments contained in piston cores from the Ross Sea. The goals of this work are to (1) document the nature and distribution of carbonate sediments on the Ross Sea continental shelf and (2) examine temporal relationships to Quaternary glaciation. Results will be used to develop criteria that will improve understanding of analogous deposits in the ancient record. All carbonate-rich intervals in piston cores from the Ross Rea, now housed at the Antarctic Marine Geology Research Facility at Florida State University, were examined and described in detail. Sediment samples were disaggregated and sieved into size fractions before description with paleontological analysis carried out on the coarsest size fraction (>250 microns). Carbonate-rich sediments are concentrated in the northwestern Ross Sea, along the distal margins of Mawson and Pennell Banks. Calcareous facies include a spectrum of lithologies that range from fossiliferous mud, sand, and gravel to skeletal floatstone-rudstone and bafflestone. Floatstone-rudstone and bafflestone is most abundant along western-facing slopes in areas protected from the Antarctic Coastal Current. Sand-prone facies dominate the tops of banks and mud-prone, often spicultic, facies occur in deeper areas. The carbonate factory is characterized by a low-diversity, heterozoan assemblage that is dominated by stylasterine hydrocorals, barnacles, and bryozoans. Molluscs and echinoids are present but not abundant. Planktic and benthic foraminifera are ubiquitous components of the sediment matrix, which is locally very rich in sponge spicules. Biota rarely

  14. Cluster Implantation and Deposition Apparatus

    DEFF Research Database (Denmark)

    Hanif, Muhammad; Popok, Vladimir

    In the current report, a design and capabilities of a cluster implantation and deposition apparatus (CIDA) involving two different cluster sources are described. The clusters produced from gas precursors (Ar, N etc.) by PuCluS-2 can be used to study cluster ion implantation in order to develop...... contributions to the theory of cluster stopping in matter as well as for practical applications requiring ultra-shallow implantation and modification of surfaces on the nanoscale. Metal clusters from the magnetron cluster source are of interest for the production of optical sensors to detect specific biological...

  15. Directional material probe for deposition layer studies

    International Nuclear Information System (INIS)

    A simple new tool for deposition layer studies, a directional material probe, is proposed. The probe, which examines the directionality of deposition layer formation, consists of a flat disk and pin. If deposits have directionality, a shadow of the pin is formed on the deposition layer on the disk. If no shadow appears on the deposition layer, this suggests that the deposition layer was formed isotropically. The probe can be applied to plasma-wall interaction studies in fusion devices and laboratory plasma devices such as linear divertor simulators to reveal the material migration mechanisms in such devices. The directional material probe method has been applied to plasma-wall interaction studies in the Large Helical Device (LHD), and a position-dependent variation in the directionality of deposition layer formation was found. (author)

  16. Remediation of spent block in Uvanas deposit

    International Nuclear Information System (INIS)

    In 2007 by 'Kazatomprom' and 'Mining company' board decision, the branch of 'Mining company', 'Steppe ore management body' is reorganized in structure subdivision, the basic activity of which is organization and carrying out remediation works on spent blocks of PSV uranium deposit. In 2002 works are completed on OVOS for operating deposits Uvanas, Kanjugan, Northern Karamurun and Eastern Minkuduk. The results of present work were reported in IAEA conference. The working project 'Remediation of spent blocks of PSV uranium deposit PV-17 polygon of Steppe ore management body' approved in 2005 was developed for carrying out the remediation works. Works funding were carried out from liquidation fund of the current deposit established in accordance with the Republic of Kazakhstan law 'About interior and interior use'. Deposits remediation is the part of deposit operation life cycle which obliges to operate deposits with minimum expenditures for remediation.

  17. Energetic deposition of thin metal films

    CERN Document Server

    Al-Busaidy, M S K

    2001-01-01

    deposited films. The primary aim of this thesis was to study the physical effect of energetic deposition metal thin films. The secondary aim is to enhance the quality of the films produced to a desired quality. Grazing incidence X-ray reflectivity (GIXR) measurements from a high-energy synchrotron radiation source were carried out to study and characterise the samples. Optical Profilers Interferometery, Atomic Force Microscope (AFM), Auger electron spectroscopy (AES), Medium energy ion spectroscopy (MEIS), and the Electron microscope studies were the other main structural characterisation tools used. AI/Fe trilayers, as well as multilayers were deposited using a Nordico planar D.C. magnetron deposition system at different voltage biases and pressures. The films were calibrated and investigated. The relation between energetic deposition variation and structural properties was intensely researched. Energetic deposition refers to the method in which the deposited species possess higher kinetic energy and impact ...

  18. Depositing Materials on the Micro- and Nanoscale

    DEFF Research Database (Denmark)

    Mar, Mikkel Dysseholm; Herstrøm, Berit; Shkondin, Evgeniy;

    2014-01-01

    that can be used separately or in combination to give the micro/nano system the properties needed. These techniques and film properties are presented. ALD (Atomic Layer Deposition) is good for very thin films (down to monolayers) with extremely good stepcoverage and extremely good control of the layer...... good for high quality thin film metal deposition e.g. for electrical leads or surfaceplasmonic devices. MVD (Molecular Vapor Deposition) is used for making anti stiction coating. Below is shown an example of Atomic Layer Deposition which is a self-terminating chemical vapor deposition technique based......, layers with specific optical properties in optical sensors, piezoelectric thin films or insulating layers in many other applications. These different materials and properties impose a demand for different kind of deposition techniques. At DTU Danchip we have a large variety of these deposition techniques...

  19. Legal Deposit of Digital Materials

    Directory of Open Access Journals (Sweden)

    Erik Oltmans

    2003-09-01

    Full Text Available Digital publishing is causing a real paradigm shift for research institutions and publishers, as well as for libraries. As a consequence these institutions have to develop new policies, new business models and new infrastructures and techniques. A major problem is that, at the same rate at which our world is becoming digital, the digital information is threatened. New types of hardware, computer applications and file formats supersede each other, making our recorded digital information inaccessible in the long-term. In the past years libraries and archives have undertaken several actions and studies on digital preservation issues. For instance the Koninklijke Bibliotheek (KB has jointly with IBM developed a standard-based deposit system: Digital Information Archiving System ( DIAS. Using DIAS the KB realised in 2002 an electronic deposit (the e-Depot and signed archiving agreements with major science publishers for permanent keeping of their digital materials. In this paper I will discuss the fully operational e-Depot at the KB. I will focus on the data flow of processing the digital publications, and I will address the issue of digital preservation in detail.

  20. Digital electrospray for controlled deposition.

    Science.gov (United States)

    Deng, Weiwei; Waits, C Mike; Gomez, Alessandro

    2010-03-01

    Many novel functional structures are now fabricated by controlled deposition as a maskless, bottom-up fabrication technique. These applications require rapid and precise deposition of minute amounts of solutions/suspensions or their ultimate particle products in predefined patterns. The electrospray is a promising alternative to the commonly used inkjet printing because it can easily handle highly viscous liquid, avoid high shear rates, and has low risk of clogging. We demonstrate a proof-of-concept digital electrospray. This system consists of a 61-nozzle array microfabricated in silicon and a 61-element digital extractor fabricated using flexible polyimide substrates. "Digital" refers to the state of each electrospray source that can be tuned either on or off independently and responsively. We showed a resolution of 675 mum and a response frequency up to 100 Hz. With similar design and industry standard fabrication procedures, it is feasible to scale up the system to O(1000) sources with spatial resolution better than 250 mum and a O(kHz) response frequency. The latter is controlled by the viscous damping time. PMID:20370220

  1. Nanofriction properties of molecular deposition films

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The nanofriction properties of Au substrate and monolayer molecular deposition film and multilayer molecular deposition films on Au substrate and the molecular deposition films modified with alkyl-terminal molecule have been investigated by using an atomic force microscope. It is concluded that (ⅰ) the deposition of molecular deposition films on Au substrate and the modification of alkyl-terminal molecule to the molecular deposition films can reduce the frictional force; (ⅱ) the molecular deposition films with the same terminal exhibit similar nanofriction properties, which has nothing to do with the molecular chain-length and the layer number; (ⅲ) the unstable nanofriction properties of molecular deposition films are contributed to the active terminal of the molecular deposition film, which can be eliminated by decorating the active molecular deposition film with alkyl-terminal molecule, moreover, the decoration of alkyl-terminal molecule can lower the frictional force conspicuously; (ⅳ) the relative humidity affects the frictional force; the higher the RH, the lower the frictional force.

  2. Revealing the effect of electrode materials on the performance of low-voltage pentacene thin film transistor by in-situ surface potential measurement

    Science.gov (United States)

    Chen, Q. L.; Ouyang, M.; Liu, Q. C.; Jin, H. Y.; Xie, W. G.

    2015-12-01

    We investigate the effect of contact potential between Au, CuOx and Au-CuOx, and pentacene thin films by Kevin Probe microscopy Compared to the Au contact, although the injection barrier is lower for CuOx contact, the extraction barrier is higher, and the total contact resistance is only slightly smaller. The better performance of CuOx contact device results from the doping effect from the p-type CuOx. The introduction of additional Au top layer deposited on the thin CuOx layer lowersthe extraction barrier and facilitates better carrier transfer, which further reduces the contact resistance. Therefore, both the apparent mobility and channel mobility are the best in the device with Au-CuOx double layer contact.

  3. Oil shales, evaporites and ore deposits

    Science.gov (United States)

    Eugster, Hans P.

    1985-03-01

    The relationships between oil shales, evaporites and sedimentary ore deposits can be classified in terms of stratigraphic and geochemical coherence. Oil shale and black shale deposition commonly follows continental red beds and is in turn followed by evaporite deposition. This transgressive-regressive sequence represents an orderly succession of depositional environments in space and time and results in stratigraphic coherence. The amount of organic carbon of a sediment depends on productivity and preservation, both of which are enhanced by saline environments. Work on Great Salt Lake. Utah, allows us to estimate that only 5% of TOC originally deposited is preserved. Inorganic carbonate production is similar to TOC production, but preservation is much higher. Oil shales and black shales commonly are enriched in heavy metals through scavenging by biogenic particles and complexation by organic matter. Ore deposits are formed from such rocks through secondary enrichment processes, establishing a geochemical coherence between oil shales and ore deposits. The Permian Kupferschiefer of N. Europe is used as an example to define a Kupferschiefer type (KST) deposit. Here oxygenated brines in contact with red beds become acidified through mineral precipitation and acquire metals by dissolving oxide coatings. Oxidation of the black shale leads to further acid production and metal acquisition and eventually to sulfide deposition along a reducing front. In order to form ore bodies, the stratigraphic coherence of the red bed-black shale-evaporite succession must be joined by the geochemical coherence of the ore body-evaporite-black shale association. The Cretaceous Cu-Zn deposits of Angola, the Zambian Copperbelt as well as the Creta, Oklahoma, deposits are other KST examples. In the Zambian Copperbelt, evaporites are indicated by the carbonate lenticles thought to be pseudomorphs after gypsum-anhydrite nodules. MVT deposits are also deposited by acid brines, but at more

  4. Ore-Forming Fluid Geochemical Characteristics and Genesis of Pb-Zn Deposit in Hongling,Inner Mongolia%内蒙古红岭铅锌矿床成矿流体地球化学特征及矿床成因

    Institute of Scientific and Technical Information of China (English)

    李剑锋; 王可勇; 陆继胜; 张雪冰; 权鸿雁; 王承洋; 魏良民

    2015-01-01

    Hongling lead-zinc deposit is one of the representative large deposits in southeastern Inner Mongolia.Presently,there’s very little research on geochemical characteristics and evolution of ore-form fluids,and ore genesis.The fluid inclusions are systemly re-searched in this paper,The results show that there are three types of primary fluid inclusions in garnet of garnet-skarn stage (Ⅰ)inclu-ding halite-bearing three-phase,aqueous two-phase as well as vapor-rich two-phase;there are two types of primary fluid inclusions in quartz of stage (Ⅱ)including aqueous two-phase as well as vapor-rich two-phase.It is found in our microthermometric study that the ore-forming fluid is of high temperature,high salinity and immiscible NaCl-H2 O type solutions and the boiling process plays important role in the precipitation of Pb,Zn,and Cu.Quartz of mineralization stage Ⅲ to Ⅳ of quartz-sulfide epochs contains only aqueous two-phase of fluid inclusions.The homogenization temperature of this type of fluid inclusions is obviously lower than that of skarn epoch, while the salinity does not obviously change.The homogenization temperatures of fluid inclusions show a rising trend with salinities dis-playing a dropping trend of stage Ⅳ,and it may be caused by adding of high temperature,low salinity type fluid.The dropping of homogenization temperatures and salinities of ore-forming fluids from mineralization stages Ⅴ to Ⅵ suggests that meteoric water contin-uously joining into the ore-forming fluid.Overall,the ore-forming fluids of quartz-sulfide epoch is of medium-low temperature and low salinity NaCl-H2 O type solutions.C,H,O isotope study of fluid inclusions shows that the ore-forming fluids of skarn epoch mainly came from magmatic water and that of quartz-sulfide epoch came from mixed magmatic water and meteoric water,whereas at the latest stage of mineralization,the ore-forming fluids mainly came from meteoric water.The study of S,Pb isotopes implies that the ore

  5. Particle deposition in turbulent flow

    Energy Technology Data Exchange (ETDEWEB)

    Ranegger, G.; Schaflinger, U. [Technical Univ. Graz (Austria). CD-Lab. of Continuous Casting Processes

    2001-07-01

    During continuous casting processes impurities like deoxidation products in the melt deposit at the walls of the tundish nozzle and the stopper. This phenomenon, termed clogging, causes obstruction of the flow and decreases the quality of the casted metal. A knowledge of the flow pattern within the tundish nozzle-stopper region is very important for the design of the nozzle and the stopper. The transport of the particles will be calculated by using a Lagrangian approach. To simulate the turbulent fluctuations in the Lagrangian formulation, a stochastic procedure (Random Walk Model) will be employed. A new design for the nozzle and stopper region reduces turbulence, prevents recirculation and permits only a very limited lateral particle transport. (orig.)

  6. Analysing the Cenozoic depositional record

    DEFF Research Database (Denmark)

    Goledowski, Bartosz; Clausen, O.R.; Nielsen, S.B.

    between the global climate record (oxygen isotopes) and lithology variations on the Eocene-Oligocene transition in the eastern North Sea. Due to the strongly limited time resolution of low temperature thermochronology, the Cenozoic sedimentary record potentially provides the most detailed history of...... lower limit to erosion rate in source areas of the respective sedimentary bodies. The lower limit arises because some erosional products are transported out of the mapped area, and some erosion is caused by chemical dissolution. The development of the source areas will be modelled using surface process...... models. The matrix mass deposition history will be compared with the paleoclimate record (e.g. oxygen isotope curves) to see if the previously observed correlation in the eastern North Sea can be extended to other ages and locations.  ...

  7. UFOMOD - atmospheric dispersion and deposition

    International Nuclear Information System (INIS)

    The report gives an introduction into the modelling of atmospheric dispersion and deposition which has been implemented in the new program system UFOMOD for assessing the consequences after nuclear accidents. According to the new structure of UFOMOD, different trajectory models with ranges of validity near to the site and at far distances are applied. Emphasis is laid on the description of the segmented plume model MUSEMET and its affilated submodels, being the removal of activity from the cloud by dry and wet deposition, and special effects like plume rise and the behaviour of plumes released into building wakes. In addition, the evaluation of γ-dose correction factors to take account of the finite extent of the radioactive plume in the near range (up to about 20 km) are described. Only brief introductions are given into the principles of the other models available: the puff model RIMPUFF, the long-range puff model MESOS, and the special straight-line Gaussian model ISOLA which are used if low-level long-duration releases are considered. To define starting times of weather sequences and the probabilities of occurrence of these sequences, it is convenient to perform stratified sampling. Therefore, the preprocessing program package METSAM has been developed to perform for generic ACAs a random sampling of weather sequences out off a population of classified weather conditions. The sampling procedure and a detailed input/output (I/O) description is presented and an additional appendix, respectively. A general overview on the I/O structure of MUSEMET as well as a brief user guide to run the KfK version of the MESOS code are also given in the appendix. (orig.)

  8. Update on calcium pyrophosphate deposition.

    Science.gov (United States)

    Abhishek, Abhishek; Doherty, Michael

    2016-01-01

    Calcium pyrophosphate crystal deposition (CPPD) associates with ageing, osteoarthritis (OA), uncommon metabolic diseases, mutations and polymorphisms in the ankylosis human gene (ANKH). CPPD is frequently polyarticular, occurs due to a generalised articular predisposition, and the association between CPPD and OA is joint specific, for example CPPD associates with knee OA, but not with hip OA. Other recently identified associations include knee malalignment (knee CC), low cortical BMD and soft-tissue calcification. CPPD is generally asymptomatic. A recent study reported that knees with OA plus CC at the index joint, or at distant joints (in absence of index joint CC), were more likely to have attrition. CPPD can cause acute CPP crystal arthritis, chronic CPP crystal inflammatory arthritis, and is frequently present in joints with OA. Joint aspiration remains the gold standard for diagnosing CPPD, although other promising techniques are emerging. Patients with polyarticular or young onset CPPD should be screened for underlying metabolic abnormalities, however, such testing can be unrewarding. The treatment of CPPD is symptomatic. Acute CPP crystal arthritis is treated with rest, local application of ice-packs, joint aspiration, colchicine and/or intra-articular corticosteroid injection (once infection is excluded). Colchicine, low-dose corticosteroids, hydroxychloroquine and radiosynovectomy are recommended for the treatment of chronic or recurrent acute CPP crystal arthritis. Recent RCTs did not confirm any benefit from methotrexate, and although there is increasing interest in the use of anti-IL1 agents for acute or chronic CPP crystal arthritis, their efficacy has not been formally examined. Unlike gout, currently there are no treatments to eliminate CPP crystal deposits. PMID:27586801

  9. Modeling particle deposition on HVAC heat exchangers

    International Nuclear Information System (INIS)

    Fouling of fin-and-tube heat exchangers by particle deposition leads to diminished effectiveness in supplying ventilation and air conditioning. This paper explores mechanisms that cause particle deposition on heat exchanger surfaces. We present a model that accounts for impaction, diffusion, gravitational settling, and turbulence. Simulation results suggest that some submicron particles deposit in the heat exchanger core, but do not cause significant performance impacts. Particles between 1 and 10(micro)m deposit with probabilities ranging from 1-20% with fin edge impaction representing the dominant mechanism. Particles larger than 10(micro)m deposit by impaction on refrigerant tubes, gravitational settling on fin corrugations, and mechanisms associated with turbulent airflow. The model results agree reasonably well with experimental data, but the deposition of larger particles at high velocities is underpredicted. Geometric factors, such as discontinuities in the fins, are hypothesized to be responsible for the discrepancy

  10. Iron-sulfide crystals in probe deposits

    DEFF Research Database (Denmark)

    Laursen, Karin; Frandsen, Flemming

    1998-01-01

    Iron-sulfides were observed in deposits collected on a probe inserted at the top of the furnace of a coal-fired power station in Denmark. The chemical composition of the iron-sulfides is equivalent to pyrrhotite (FeS). The pyrrhotites are present as crystals and, based on the shape of the crystals......, it was deduced that they were not deposited but instead grew within the deposit. The presence of unburned char particles within the deposits supports the concept that a reducing environment existed in the deposits. Two processes are proposed for explaining the existence of pyrrhotite crystals within...... a deposit: (1) impact of low viscous droplets of iron sulfide; and (2) sulfur diffusion. Previous research on the influence of pyrite on slagging focused on the decomposition of pyrite into pyrrhotite and especially on the oxidation stage of this product during impact on the heat transfer surfaces...

  11. Laboratory Deposition Apparatus to Study the Effects of Wax Deposition on Pipe Magnetic Field Leakage Signals

    Directory of Open Access Journals (Sweden)

    Karim Mohd Fauzi Abd

    2014-07-01

    Full Text Available Accurate technique for wax deposition detection and severity measurement on cold pipe wall is important for pipeline cleaning program. Usually these techniques are validated by conventional techniques on laboratory scale wax deposition flow loop. However conventional techniques inherent limitations and it is difficult to reproduce a predetermine wax deposit profile and hardness at designated location in flow loop. An alternative wax deposition system which integrates modified pour casting method and cold finger method is presented. This system is suitable to reproduce high volume of medium hard wax deposit in pipe with better control of wax deposit profile and hardness.

  12. Review of cooling tower drift deposition models

    Energy Technology Data Exchange (ETDEWEB)

    Chen, N.C.J.

    1977-05-04

    The behavior, basic assumptions, and limitations of ten different models for calculating the drift deposition rate from wet cooling towers are reviewed and then their predicted results for such deposition with a common set of input parameters are compared. The predicted maximum deposition differs among the models by two orders of magnitude with a wide range in peak location. Comments and suggestions to improve the models are included.

  13. FTIR analysis of aviation fuel deposits

    Science.gov (United States)

    Helmick, L. S.; Seng, G. T.

    1984-01-01

    Five modes of operation of the Nicolet 7199 Fourier Transform Infrared Spectrophotometer have been evaluated for application in analysis of the chemical structure of accelerated storage/thermal deposits produced by jet fuels. Using primarily the absorption and emission modes, the effects of fuel type, stress temperature, stress time, type of spiking agent, spiking agent concentration, fuel flow, and post-depositional treatment on the chemical nature of fuel deposits have been determined.

  14. Vapor wall deposition in Teflon chambers

    OpenAIRE

    Zhang, X; R. H. Schwantes; R. C. McVay; H Lignell; M. M. Coggon; Flagan, R C; Seinfeld, J.H.

    2014-01-01

    Teflon chambers are ubiquitous in studies of atmospheric chemistry. Secondary organic aerosol (SOA) formation can be substantially underestimated owing to deposition of SOA-forming compounds to chamber walls. We present here an experimental protocol to constrain the nature of wall deposition of organic vapors in Teflon chambers. We measured the wall deposition rates of 25 oxidized organic compounds generated from the photooxidation of isoprene, toluene, α-pinene, and dodecan...

  15. Low-fluorine Stockwork Molybdenite Deposits

    Science.gov (United States)

    Ludington, Steve; Hammarstrom, Jane; Piatak, Nadine M.

    2009-01-01

    Low-fluorine stockwork molybdenite deposits are closely related to porphyry copper deposits, being similar in their tectonic setting (continental volcanic arc) and the petrology (calc-alkaline) of associated igneous rock types. They are mainly restricted to the Cordillera of western Canada and the northwest United States, and their distribution elsewhere in the world may be limited. The deposits consist of stockwork bodies of molybdenite-bearing quartz veinlets that are present in and around the upper parts of intermediate to felsic intrusions. The deposits are relatively low grade (0.05 to 0.2 percent Mo), but relatively large, commonly >50 million tons. The source plutons for these deposits range from granodiorite to granite in composition; the deposits primarily form in continental margin subduction-related magmatic arcs, often concurrent with formation of nearby porphyry copper deposits. Oxidation of pyrite in unmined deposits or in tailings and waste rock during weathering can lead to development of acid-rock drainage and limonite-rich gossans. Waters associated with low-fluorine stockwork molybdenite deposits tend to be nearly neutral in pH; variable in concentrations of molybdenum (10,000 ug/L); below regulatory guidelines for copper, iron, lead, zinc, and mercury; and locally may exceed guidelines for arsenic, cadmium, and selenium.

  16. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  17. Boron deposition from fused salts. Final report

    International Nuclear Information System (INIS)

    A partial evaluation of the feasibility of a process to electrodeposit pure coherent coatings of elemental boron from molten fluorides has been performed. The deposit produced was powdery and acicular, unless the fluoride melt was purified to have very low oxygen concentration. When the oxygen activity was reduced in the melt by addition of crystalline elemental boron, dense, amorphous boron deposit was produced. The boron deposits produced had cracks but were otherwise pure and dense and ranged up to 0.35 mm thick. Information derived during this project suggests that similar deposits might be obtained crack-free up to 1.00 mm thick by process modifications and improvements

  18. Structural characterization of MAPLE deposited lipase biofilm

    International Nuclear Information System (INIS)

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase

  19. Kaolinite influence on calcareous deposit formation

    International Nuclear Information System (INIS)

    This study investigate the influence of kaolinite, introduced in electrolytes solutions, on the calcareous deposit formation, which is monitored by chronoamperometric measurements coupled with chemical impedance spectroscopy analyses. The deposits formed are observed by scanning electron microscopy and analysed by Raman spectroscopy and X-ray diffraction analyses. In presence of Mg2+ ions, kaolinite delay the deposit formation, preventing the reduction of energy required for an efficient cathodic protection. Whereas no influence of this clay was noticed on the CaCO3 deposit when the electrolyte was totally exempt of Mg2+.

  20. Atomic layer deposition of nanoporous biomaterials

    Directory of Open Access Journals (Sweden)

    Roger J Narayan

    2010-03-01

    Full Text Available Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials.

  1. Regional aerosol deposition in human upper airways

    International Nuclear Information System (INIS)

    During the report period significant progress on the quantitative understanding of regional upper airway deposition of airborne particle has been realized. Replicate models of the human upper airways obtained from post-mortem casting of the nasal, oral, pharyngeal, laryngeal and upper tracheal regions and in vivo magnetic resonance imaging (MRI) of the same regions of adults and children have been employed to determine the overall and local deposition characteristics of aerosols in the ultrafine (1--100 μm diameter) and fine (0.8--12 μm diameter) region. Studies have been carried out for both nasal and oral breathing during inspiratory and expiratory flow at constant flow rates representative of rest and states of exercise. The results of these investigations indicate that particles in the size range of ''unattached'' radon progeny (1--3 nm) are deposited in both the nasal and oral passages with high efficiency (60--80%) for both inspiration and expiration, with the nasal deposition being somewhat greater (5--10%) than oral deposition. The effect of flow rate on upper airway deposition for both pathways is not great; data analysis indicates that the deposition for all flow rates from 4--50 liters/minute can be grouped by plotting deposition vs Q-1/8, where Q is flow rate, a far weaker dependency than observed for inertial deposition. Diffusional transport is the primary mechanism of deposition, and size dependence can be accounted for by plotting, deposition percent vs Dn where D is particle diffusion coefficient and n ranges from 0.5--0.66. 2 refs

  2. Predicting particle deposition on HVAC heat exchangers

    Science.gov (United States)

    Siegel, Jeffrey A.; Nazaroff, William W.

    Particles in indoor environments may deposit on the surfaces of heat exchangers that are used in heating, ventilation and air conditioning (HVAC) systems. Such deposits can lead to performance degradation and indoor air quality problems. We present a model of fin-and-tube heat-exchanger fouling that deterministically simulates particle impaction, gravitational settling, and Brownian diffusion and uses a Monte Carlo simulation to account for impaction due to air turbulence. The model predicts that heat exchangers with air flows and fin spacings that are typical of HVAC systems. For supermicron particles, deposition increases with particle size. The dominant deposition mechanism for 1-10 μm particles is impaction on fin edges. Gravitational settling, impaction, and air turbulence contribute to deposition for particles larger than 10 μm. Gravitational settling is the dominant deposition mechanism for lower air velocities, and impaction on refrigerant tubes is dominant for higher velocities. We measured deposition fractions for 1-16 μm particles at three characteristic air velocities. On average, the measured results show more deposition than the model predicts for an air speed of 1.5 m s -1. The amount that the model underpredicts the measured data increases at higher velocities and especially for larger particles, although the model shows good qualitative agreement with the measured deposition fractions. Discontinuities in the heat-exchanger fins are hypothesized to be responsible for the increase in measured deposition. The model and experiments reported here are for isothermal conditions and do not address the potentially important effects of heat transfer and water phase change on deposition.

  3. Hideout in steam generator tube deposits

    International Nuclear Information System (INIS)

    Hideout in deposits on steam generator tubes was studied using tubes coated with magnetite. Hideout from sodium chloride solutions at 279 degrees C was followed using an on-line high-temperature conductivity probe, as well as by chemical analysis of solution samples from the autoclave in which the studies were done. Significant hideout was observed only at a heat flux greater than 200 kW/m2, corresponding to a temperature drop greater than 2 degrees C across the deposits. The concentration factor resulting from the hideout increased highly non-linearly with the heat flux (varying as high as the fourth power of the heat flux). The decrease in the apparent concentration factor with increasing deposit thickness suggested that the pores in the deposit were occupied by a mixture of steam and water, which is consistent with the conclusion from the thermal conductivity measurements on deposits in a separate study. Analyses of the deposits after the hideout tests showed no evidence of any hidden-out solute species, probably due to the concentrations being very near the detection limits and to their escape from the deposit as the tests were being ended. This study showed that hideout in deposits may concentrate solutes in the steam generator bulk water by a factor as high as 2 x 103. Corrosion was evident under the deposit in some tests, with some chromium enrichment on the surface of the tube. Chromium enrichment usually indicates an acidic environment, but the mobility required of chromium to become incorporated into the thick magnetite deposit may indicate corrosion under an alkaline environment. An alkaline environment could result from preferential accumulation of sodium in the solution in the deposit during the hideout process. (author)

  4. Yangshan Gold Deposit: The Largest Carlin and Carlin-like Type Gold Deposit in China

    Institute of Scientific and Technical Information of China (English)

    YAN Fengzeng; LI Qiangzhi

    2008-01-01

    Gold Headquarter of the CAPF has discovered the Yangshan super large-scale gold depositin Gansu Province, which is a great breakthrough of gold exploration and prospecting in WesternQiniing Mountains of China. The gold resources of this deposit achieved 308 tons with increasingpotentials. Preliminary geological investigations indicate that the Yangshan gold deposit is located inthe intra-continental collision orogenic belt; and the deposit was formed during the continent-continentcollision orogenic processes. The geological characteristics of the deposit are similar to that of thetypical Carlin-type gold deposits, while differences still exist. The ore-forming background is notablydifferent from the Carlin gold deposit province in the United States; and the ore-forming fluids aresimilar with that of the orogenic-type gold deposit. Accordingly, the Yangshan gold deposit is atransitional type between the Carlin-type and the orogenic type gold deposits. At present, the Yangshangold deposit is the largest Carlin and Carlin-like type gold deposit that is ever discovered in China.Researches on metaliogeny, metaliogenic model and ore-enrichment regularities of the Yangshan golddeposit are crucial to meet the pressing needs of the current geological investigation and oreexploration of the deposit.

  5. 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 Dece

  6. Resource assessment of copper deposits in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qin-li; GU De-sheng; T. Shoji; H. Kaneda

    2005-01-01

    Copper-bearing deposits of China are statistically analyzed in terms of ore grade, metal amount and ore tonnage. Each of grade and metal amount shows more or less a lognormal distribution. Analysis gives 10 copper metallogenic districts, each having specific densities of deposit numbers and copper reserves larger than 3. Based on the ratio of copper in ore value (Rcu), Chinese copper deposits are classified into two groups: mainly copper-producing deposits (MC: Rcu≥0.5) and accessorily copper-producing deposits (AC: Rcu<0. 5). The grade-tonnage relation of MC deposits can be combined by two exponential functions approximating high grade (> 3.0 %) and low grade (<2.0%) parts. The critical copper grade, which is obtained from the low grade part of the relation, is 0. 34 %. Chinese copper resources are concluded to become pessimistic, because some mines are working with grades close to this critical value. Taking account of the fact that many copper deposits are actually polymetallic, Cu-equivalent grades, which are converted from ratios of metal prices to the copper price, are also introduced. The critical Cu-equivalent grade of MC deposits (0. 43 % ) also suggests that Chinese copper resources are pessimistic.

  7. 10 CFR 2.1019 - Depositions.

    Science.gov (United States)

    2010-01-01

    ... Applicable to Proceedings for the Issuance of Licenses for the Receipt of High-Level Radioactive Waste at a... take the testimony of any person by deposition on oral examination shall, without leave of the... place of taking the deposition; the name and address of each person to be examined, if known, or if...

  8. 49 CFR 1114.24 - Depositions; procedures.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Depositions; procedures. 1114.24 Section 1114.24... OF TRANSPORTATION RULES OF PRACTICE EVIDENCE; DISCOVERY Discovery § 1114.24 Depositions; procedures... provided in § 1114.21(c). If the order made terminates the examination, it should be resumed...

  9. 49 CFR 1114.22 - Deposition.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Deposition. 1114.22 Section 1114.22 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE EVIDENCE; DISCOVERY Discovery § 1114.22 Deposition. (a) Purpose. The...

  10. Assessment of Global Mercury Deposition through Litterfall.

    Science.gov (United States)

    Wang, Xun; Bao, Zhengduo; Lin, Che-Jen; Yuan, Wei; Feng, Xinbin

    2016-08-16

    There is a large uncertainty in the estimate of global dry deposition of atmospheric mercury (Hg). Hg deposition through litterfall represents an important input to terrestrial forest ecosystems via cumulative uptake of atmospheric Hg (most Hg(0)) to foliage. In this study, we estimate the quantity of global Hg deposition through litterfall using statistical modeling (Monte Carlo simulation) of published data sets of litterfall biomass production, tree density, and Hg concentration in litter samples. On the basis of the model results, the global annual Hg deposition through litterfall is estimated to be 1180 ± 710 Mg yr(-1), more than two times greater than the estimate by GEOS-Chem. Spatial distribution of Hg deposition through litterfall suggests that deposition flux decreases spatially from tropical to temperate and boreal regions. Approximately 70% of global Hg(0) dry deposition occurs in the tropical and subtropical regions. A major source of uncertainty in this study is the heterogeneous geospatial distribution of available data. More observational data in regions (Southeast Asia, Africa, and South America) where few data sets exist will greatly improve the accuracy of the current estimate. Given that the quantity of global Hg deposition via litterfall is typically 2-6 times higher than Hg(0) evasion from forest floor, global forest ecosystems represent a strong Hg(0) sink. PMID:27418119

  11. Large Nonferrous Metals Deposits Found in Yunnan

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>According to the Department of Land and Resources of Yunnan, Yunnan has made great achievements since implementation of the geological prospecting action plan. 5 ultra-large deposits and several large deposits have been found, and a group of key areas with favorable ore-forming prospect have been pinpointed.

  12. Uranium deposits of Australia to 1975

    International Nuclear Information System (INIS)

    This bibliography provides a retrospective account of Australian uranium deposits, particularly the unpublished materials in the Australian Capital Territory. Some abstracts are included. Occurrences, mineralogy, ore genesis, structural controls and the eonomic geology of uranium deposits are covered but the mining of uranium, exploration reports, surveys, environmental aspects and controversial materials are not

  13. Time Resolved Deposition Measurements in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    C.H. Skinner; H. Kugel; A.L. Roquemore; J. Hogan; W.R. Wampler; the NSTX team

    2004-08-03

    Time-resolved measurements of deposition in current tokamaks are crucial to gain a predictive understanding of deposition with a view to mitigating tritium retention and deposition on diagnostic mirrors expected in next-step devices. Two quartz crystal microbalances have been installed on NSTX at a location 0.77m outside the last closed flux surface. This configuration mimics a typical diagnostic window or mirror. The deposits were analyzed ex-situ and found to be dominantly carbon, oxygen, and deuterium. A rear facing quartz crystal recorded deposition of lower sticking probability molecules at 10% of the rate of the front facing one. Time resolved measurements over a 4-week period with 497 discharges, recorded 29.2 {micro}g/cm{sup 2} of deposition, however surprisingly, 15.9 {micro}g/cm{sup 2} of material loss occurred at 7 discharges. The net deposited mass of 13.3 {micro}g/cm{sup 2} matched the mass of 13.5 {micro}g/cm{sup 2} measured independently by ion beam analysis. Monte Carlo modeling suggests that transient processes are likely to dominate the deposition.

  14. Time Resolved Deposition Measurements in NSTX

    International Nuclear Information System (INIS)

    Time-resolved measurements of deposition in current tokamaks are crucial to gain a predictive understanding of deposition with a view to mitigating tritium retention and deposition on diagnostic mirrors expected in next-step devices. Two quartz crystal microbalances have been installed on NSTX at a location 0.77m outside the last closed flux surface. This configuration mimics a typical diagnostic window or mirror. The deposits were analyzed ex-situ and found to be dominantly carbon, oxygen, and deuterium. A rear facing quartz crystal recorded deposition of lower sticking probability molecules at 10% of the rate of the front facing one. Time resolved measurements over a 4-week period with 497 discharges, recorded 29.2 (micro)g/cm2 of deposition, however surprisingly, 15.9 (micro)g/cm2 of material loss occurred at 7 discharges. The net deposited mass of 13.3 (micro)g/cm2 matched the mass of 13.5 (micro)g/cm2 measured independently by ion beam analysis. Monte Carlo modeling suggests that transient processes are likely to dominate the deposition

  15. Atmospheric deposition maps for the Rocky Mountains

    Science.gov (United States)

    Nanus, L.; Campbell, D.H.; Ingersoll, G.P.; Clow, D.W.; Mast, M.A.

    2003-01-01

    Variability in atmospheric deposition across the Rocky Mountains is influenced by elevation, slope, aspect, and precipitation amount and by regional and local sources of air pollution. To improve estimates of deposition in mountainous regions, maps of average annual atmospheric deposition loadings of nitrate, sulfate, and acidity were developed for the Rocky Mountains by using spatial statistics. A parameter-elevation regressions on independent slopes model (PRISM) was incorporated to account for variations in precipitation amount over mountainous regions. Chemical data were obtained from the National Atmospheric Deposition Program/National Trends Network and from annual snowpack surveys conducted by the US Geological Survey and National Park Service, in cooperation with other Federal, State and local agencies. Surface concentration maps were created by ordinary kriging in a geographic information system, using a local trend and mathematical model to estimate the spatial variance. Atmospheric-deposition maps were constructed at 1-km resolution by multiplying surface concentrations from the kriged grid and estimates of precipitation amount from the PRISM model. Maps indicate an increasing spatial trend in concentration and deposition of the modeled constituents, particularly nitrate and sulfate, from north to south throughout the Rocky Mountains and identify hot-spots of atmospheric deposition that result from combined local and regional sources of air pollution. Highest nitrate (2.5-3.0kg/ha N) and sulfate (10.0-12.0kg/ha SO4) deposition is found in northern Colorado.

  16. Plasma Deposition of Doped Amorphous Silicon

    Science.gov (United States)

    Calcote, H. F.

    1985-01-01

    Pair of reports present further experimental details of investigation of plasma deposition of films of phosphorous-doped amosphous silicon. Probe measurements of electrical resistance of deposited films indicated films not uniform. In general, it appeared that resistance decreased with film thickness.

  17. Uranium deposits of the Czech Republic

    International Nuclear Information System (INIS)

    The existing uranium production in the Czech Republic has a long tradition for about 100 years. The unimportant production of uranium ores used in the glass and ceramic industries and medicine was replaced after World War II by an intense evolution of uranium ore exploration, mining and processing activities. This whole period is characterized by a steadily increasing level, of exploration work and of linked research activities in a few stages. A substantial reduction in the volume of geological exploratory works aimed at the detection and development of new deposits occurred as a result of the contraction programme of the uranium industry, pronounced in 1989. There are only two regions with prospective uranium deposits at present time. The first one is in northern Bohemia with the Hamr and the Straz deposits in production. These deposits are connected with basal Cretaceous sediments (sandstones). The other one is in western Moravia (Moldanubian) with the Rozna and the Brzkov deposits. These deposits are connected with metamorphosed rocks of the Moldanubian. All the exploration, extraction and processing activities were operated by the state for approximately 50 years. Nowadays the only uranium producer in the Czech Republic is the DIAMO state enterprise, based in Straz pod Ralskem. The continuation of extraction is planned at the Rozna and the Hamr deposits in the near future. The ISL-production of uranium is planned at the Straz deposit during the restoration activities. (author). 4 figs, 3 tabs

  18. Deposition of contaminant aerosol on human skin

    DEFF Research Database (Denmark)

    Andersson, Kasper Grann; Roed, Jørn; Byrne, M.A.;

    2006-01-01

    Over recent years, it has been established that deposition of various types of pollutant aerosols (e.g., radioactive) on human skin can have serious deleterious effects on health. However. only few investigations in the past have been devoted to measurement of deposition velocities on skin...

  19. Energy deposition in NSRR test fuels

    International Nuclear Information System (INIS)

    Interpretation of fuel performance data collected during inpile testing in the NSRR requires a knowledge of the energy deposition or enthalpy increase in each sample tested. The report describes the results of absolute measurement of fission products and contents of uranium in irradiated test fuels which were performed to determine the energy deposition. (auth.)

  20. Ion plating technique improves thin film deposition

    Science.gov (United States)

    Mattox, D. M.

    1968-01-01

    Ion plating technique keeps the substrate surface clean until the film is deposited, allows extensive diffusion and chemical reaction, and joins insoluble or incompatible materials. The technique involves the deposition of ions on the substrate surface while it is being bombarded with inert gas ions.

  1. Microwave-enhanced thin-film deposition

    Science.gov (United States)

    Chitre, S.

    1984-01-01

    The deposition of semiconducting and insulating thin films at low temperatures using microwave technology was explored. The method of plasma formations, selection of a power source, the design of the microwave plasma cavity, the microwave circuitry, impedance matching, plasma diagnostics, the deposition chamber and the vacuum system were studied.

  2. 24 CFR 891.775 - Security deposits.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Security deposits. 891.775 Section 891.775 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... Individuals-Section 162 Assistance § 891.775 Security deposits. The general requirements for security...

  3. 37 CFR 1.25 - Deposit accounts.

    Science.gov (United States)

    2010-07-01

    ... over the Office's Internet Web site (www.uspto.gov). (3) A payment to replenish a deposit account may... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES General Provisions Fees and Payment of Money § 1.25... the Patent and Trademark Office upon payment of the fee for establishing a deposit account (§...

  4. Genetic types of uranium deposits of Ukraine

    International Nuclear Information System (INIS)

    There are three genetic classes of uranium deposits in Ukraine. Eight types of uranium deposits are described with reference to their genesis, age and geological position. The attributes of uranium concentration in Precambrian and Proterozoic periods of activization are shown. (author). 1 fig., 1 tab

  5. [Glomerulopathies with organized monoclonal immunoglobulin deposits].

    Science.gov (United States)

    Touchard, Guy; Bridoux, Frank; Goujon, Jean-Michel

    2016-02-01

    The spectrum of glomerular disorders with organized immunoglobulin (Ig) deposits is heterogeneous. It encompasses 2 mains categories: glomerulopathies with fibrillary deposits are mostly represented by immunoglobulinic amyloidosis (most commonly AL amyloidosis, characterized by monoclonal light chain deposits often of the lambda isotype), and pseudo-amyloid fibrillary glomerulonephritis in which deposits predominantly contain polyclonal IgG4. Glomerulopathies with microtubular deposits include cryoglobulinemic glomerulonephritis (type I and type II, with or without detectable serum cryoglobulin) and glomerulonephritis with organized microtubular monoclonal Ig deposits (GOMMID) also referred to as immunotactoid glomerulopathy. Pathological diagnosis requires meticulous studies by light microscopy (with systematic Congo red staining), immunofluorescence with specific conjugates, and electron microscopy. Ultrastructural studies are required to differentiate amyloid fibrils (8 to 10 nm in external diameter), pseudo-amyloid fibrils (15-20 nm) and microtubules (10 to 50 nm in external diameter, with a central hollow core). Glomerular deposits in type I cryoglobulinemic glomerulonephritis are arranged into parallel straight microtubules similar to those observed in GOMMID, but with different topography that allows distinction between the two entities. Glomerular substructures composed of circulating Igs should be distinguished from collagen fibrils that are commonly observed in glomerular disorders with or without deposition of monoclonal or polyclonal Igs. PMID:26810049

  6. Geological classification of uranium deposits

    International Nuclear Information System (INIS)

    The worst of times for the uranium producer may be over and a new episode in the tale of uranium is starting to unfold. In this next episode, trade restrictions, civilian inventories, and even HEU are drifting slowly backstage. With the changing scene-uranium prices having finally crossed the $13 per pound U3O8 threshold, and with expectations of continued strengthening-the uranium producer is once again assuming the role protagonist. The price gap that was opened with restrictions on CIS-origin uranium is now closing as this lower-priced supply appears to be scarce. Even matched sales may lose their appeal to both producer and utility. HEU and other inventories, once thought to be able to flood the market, are now turning out to be mostly pomp, with little circumstance. Meanwhile, industry participants, especially utilities, sit on the edge of their seats, already wondering if a soliloquy by the uranium producer can keep their undivided attention. The question in 1996 and through the turn of the century will be whether uranium producers are capable of mining enough uranium to satisfy utility requirements. If so, at what prices? And for how long? Where will 150 million pounds per year of uranium come from? Producers are already gearing up exploration crews in almost every continent in an effort to increase minable reserves. Some are even exploring in new areas, hopeful that lower-cost reserves will be found in addition to their discovered deposits

  7. Polymetallic uranium-copper deposits

    International Nuclear Information System (INIS)

    The present report is an addendum to the final report, dated June 30, 1988, on the research program 'Polymetallic uranium-copper deposits' and is concerned with investigations carried out in the Palaeozoic/Mesozoic basins of the Hessian Depression, FRG, in the first half of 1988. The investigations comprised the further compilation of literature data and limited field work; they were related to three objectives and yielded the following results: 1. Additional data were obtained on the geochemistry (in particular U) of the stratiform, polymetallic Cu mineralization of the Kupferschiefer type. The new data confirm the conclusions reached previously within the present research program. 2. The radiometric scanning of samples and of surface exposures and dumps from the historic mining of the 'Ruecken' veins (barite ± Co-Ni-As) in the Richelsdorfer Gebirge area yielded negative results. Follow-up investigations are not justified. 3. The occurrence of collapse structure ('Erdfaelle'), in one case combined with tensional tectonics and possible diapiric phenomena (Sontra graben structure) led to the speculation that some of these structures may host epigenetic polymetallic mineralization. Results have been negative, respectively inconclusive; a direct proof requires deeper drilling. However, based on the lack of any positive indication, follow-up investigations are not justified. (orig./RB)

  8. The geomicrobiology of bauxite deposits

    Institute of Scientific and Technical Information of China (English)

    Xiluo Hao; Kwunlun Leung; Rucheng Wang; Weidong Sun; Yiliang Li

    2010-01-01

    Bauxite deposits are studied because of their economic value and because they play an important role in the study of paleoclimate and paleogeography of continents. They provide a rare record of the weathering and evolution of continental surfaces. Geomicrobiological analysis makes it possible to verify that microorganisms have played a critical role during the formation of bauxite with the possibility already intimated in previous studies. Ambient temperature, abundance of water, organic carbon and bioavailable iron and other metal substrates provide a suitable environment for microbes to inhabit. Thiobacillus, Leptospirilum, Thermophilic bacteria and Heterotrophs have been shown to be able to oxidize ferrous iron and to reduce sulfate-generating sulfuric acid, which can accelerate the weathering of aluminosilicates and precipitation of iron oxyhydroxides. Microorganisms referred to the genus Bacillus can mediate the release of alkaline metals. Although the dissimilatory iron-reducing and sulfate-reducing bacteria in bauxites have not yet been identified, some recorded authigenic carbonates and "bacteriopyrites" that appear to be unique in morphology and grain size might record microbial activity. Typical bauxite minerals such as gibbsite, kaolinite, covellite, galena, pyrite, zircon, calcium ptagioclase, orthoclase, and albite have been investigated as part of an analysis of microbial mediation. The paleoecologyof such bauxitic microorganisms inhabiting continental (sub) surfaces, revealed through geomicrobiological analysis, will add a further dimension to paleoclimatic and paleoenvironmental studies.

  9. Thin Film Deposition Using Energetic Ions

    Directory of Open Access Journals (Sweden)

    Stephan Mändl

    2010-07-01

    Full Text Available One important recent trend in deposition technology is the continuous expansion of available processes towards higher ion assistance with the subsequent beneficial effects to film properties. Nowadays, a multitude of processes, including laser ablation and deposition, vacuum arc deposition, ion assisted deposition, high power impulse magnetron sputtering and plasma immersion ion implantation, are available. However, there are obstacles to overcome in all technologies, including line-of-sight processes, particle contaminations and low growth rates, which lead to ongoing process refinements and development of new methods. Concerning the deposited thin films, control of energetic ion bombardment leads to improved adhesion, reduced substrate temperatures, control of intrinsic stress within the films as well as adjustment of surface texture, phase formation and nanotopography. This review illustrates recent trends for both areas; plasma process and solid state surface processes.

  10. Tax evasion and Swiss bank deposits

    DEFF Research Database (Denmark)

    Johannesen, Niels

    2014-01-01

    Bank deposits in offshore financial centers may be used to evade taxes on interest income. A recent EU reform limits the scope for this type of tax evasion by introducing a withholding tax on interest income earned by EU households in Switzerland and several other offshore centers. This paper...... estimates the impact of the withholding tax on Swiss bank deposits held by EU residents while using non-EU residents who were not subject to the tax as a comparison group. We present evidence that Swiss bank deposits owned by EU residents declined by 30–40% relative to other Swiss bank deposits in two...... quarters immediately before and after the tax was introduced. We also present evidence suggesting that the drop in Swiss bank deposits was driven by behavioral responses aiming to escape the tax - such as the transfer of funds to bank accounts in other offshore centers and the transfer of formal ownership...

  11. A Complexity View of Acid Deposition

    Institute of Scientific and Technical Information of China (English)

    朱建林; 方见树

    2003-01-01

    We show that acid deposition is analogous to complex systems composed of a series of interconnected components.Frequency-size distributions of weekly hydrogen deposition (WHD) of precipitation are consistent with double power-law in two different regimes separated by a crossover WHD. The distribution of variations in acid deposition over a week interval is remarkably symmetrical, with long tail extending over eight orders of magnitude. The acid deposition fluctuations exhibit fractal Brown motion with two different temporal scaling regimes and long-range correlation exists in the series. The power-laws in the acid deposition dynamics are considered to be indicators of seff-organization of atmosphere under environmental pollution stress.

  12. Biosensor Applications of MAPLE Deposited Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2014-10-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique derived from Pulsed Laser Deposition (PLD for deposition of delicate (polymers, complex biological molecules, etc. materials in undamaged form. The main difference of MAPLE technique with respect to PLD is the target: it is a frozen solution or suspension of the (guest molecules to be deposited in a volatile substance (matrix. Since laser beam energy is mainly absorbed by the matrix, damages to the delicate guest molecules are avoided, or at least reduced. Lipase, an enzyme catalyzing reactions borne by triglycerides, has been used in biosensors for detection of β-hydroxyacid esters and triglycerides in blood serum. Enzymes immobilization on a substrate is therefore required. In this paper we show that it is possible, using MAPLE technique, to deposit lipase on a substrate, as shown by AFM observation, preserving its conformational structure, as shown by FTIR analysis.

  13. Diamond deposition on thin cylindrical substrates

    Directory of Open Access Journals (Sweden)

    GORDANA S. RISTIĆ

    2011-03-01

    Full Text Available Diamond coatings were deposited onto different cylindrical substrates (Cu, SiC, W and Mo by the hot filament chemical vapor deposition (CVD method. Continuous, adhered and well-faceted crystalline coatings of diamond were obtained on Cu-wire using a special pretreatment with a mixture of diamond and metal powders as well as carefully controlled deposition at lower power. Diamond deposition on SiC-fiber gave continuous and uniform coatings when only the filament power was properly selected. Uniform, homogeneous, euchedral diamond coatings on W- and Mo-wires, attained at a higher filament power, confirmed once more the convenience of refractory metals as substrates for diamond deposition by the CVD technique. Characterization of the obtained coatings was realized using scanning electron microscopy (SEM. The obtained results are compared with the literature data. Differences are discussed with regard to the chemical nature of the substrates as well as their thermophysical characteristics.

  14. 青海省东昆仑成矿带铁矿成矿规律与找矿方向研究%Metallogenic Law and Prospect Direction of Iron Deposits in the East Kunlun Metallogenic Belt in Qinghai

    Institute of Scientific and Technical Information of China (English)

    许长坤; 王红英; 张文君; 乔强; 刘世宝; 赵子基; 张梅芬; 张开成; 刘建华; 詹发余; 黄朝晖; 张钟月

    2012-01-01

    Early Xingkai period. East Kunlun metallogenic belt is one of the most important metallogenic belts in Qinghai with advantageous geological conditions and great prospecting potential where structures of intrusive rock, fold and fracture are well developed as well as frequent and strong magmatic activities. Moreover, this belt is also the concentrated region of major industrial ore deposits in Qinghai with large reserves and high grade and concurrently paragenic and associated poly-metallic deposit normally possess certain scale. In particularly most skarn-type and sedimentary-metamorphic iron ores are concentrated in this area. Genetic types of iron ore deposits in the East Kunlun metallogenic belt are complex, including exhalative-sedimentary and pyrometasomatic metamorphism reformation type related to volcanic exhalative sedimentation, and sedimentary metamorphic and skarn types. Therefore, the belt is provided with metallogenic conditions for large or super large ore deposits. The ore deposits distribute mostly along the deep fractures of the north, middle and south of Kunlun Mountain and are closely connected with secondary structures and magmatic rock mass. The west of East Kunlun metallogenic belt is the important prospecting area for large ore deposits, the middle has prospecting potential of sedimentary metamorphic iron ores, and the east is regarded as the accumulation area of skarn-type iron ore deposits. The resources of iron ores in this belt occupy 75. 51% of the whole province and large quantity of useful components associated with iron deposits can be also utilized. The contact-metasomatic iron deposits are the target for current exploration. The ores of this kind is excellent and the grade of TFe is between 35% and 55%, with low contents of sulphur and phosphorus (normally lower than industrial requirements). Especially in the Dulan and Yemaquan areas, the associated elements in iron depsotis, such as such as lead, zinc, copper, gold, silver, tin, cobalt

  15. Sediment-hosted stratabound copper deposit model: Chapter M in Mineral deposit model for resource assessment

    Science.gov (United States)

    Hayes, Timothy S.; Cox, Dennis P.; Bliss, James D.; Piatak, Nadine M.; Seal, Robert R., II

    2015-01-01

    This report contains a descriptive model of sediment-hosted stratabound copper (SSC) deposits that supersedes the model of Cox and others (2003). This model is for use in assessments of mineral resource potential. SSC deposits are the second most important sources of copper in the world behind porphyry copper deposits. Around 20 percent of the copper in the world is produced from this class of deposits. They are also the most important sources of cobalt in the world, and they are fourth among classes of ore deposits in production of silver. SSC deposits are the basis of the economies of three countries: Democratic Republic of Congo, Poland, and Zambia. This report provides a description of the key features of SSC deposits; it identifies their tectonic-sedimentary environments; it illustrates geochemical, geophysical, and geoenvironmental characteristics of SSC deposits; it reviews and evaluates hypotheses on how these deposits formed; it presents exploration and assessment guides; and it lists some gaps in our knowledge about the SSC deposits. A summary follows that provides overviews of many subjects concerning SSC deposits.

  16. Effects of deposition time in chemically deposited ZnS films in acidic solution

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, H.; Chelouche, A., E-mail: azeddinechelouche@gmail.com; Talantikite, D.; Merzouk, H.; Boudjouan, F.; Djouadi, D.

    2015-08-31

    We report an experimental study on the synthesis and characterization of zinc sulfide (ZnS) single layer thin films deposited on glass substrates by chemical bath deposition technique in acidic solution. The effect of deposition time on the microstructure, surface morphology, optical absorption, transmittance, and photoluminescence (PL) was investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM), UV-Vis–NIR spectrophotometry and photoluminescence (PL) spectroscopy. The results showed that the samples exhibit wurtzite structure and their crystal quality is improved by increasing deposition time. The latter, was found to affect the morphology of the thin films as showed by SEM micrographs. The optical measurements revealed a high transparency in the visible range and a dependence of absorption edge and band gap on deposition time. The room temperature PL spectra indicated that all ZnS grown thin films emit a UV and blue light, while the band intensities are found to be dependent on deposition times. - Highlights: • Single layer ZnS thin films were deposited by CBD in acidic solution at 95 °C. • The effect of deposition time was investigated. • Coexistence of ZnS and ZnO hexagonal structures for time deposition below 2 h • Thicker ZnS films were achieved after monolayer deposition for 5 h. • The highest UV-blue emission observed in thin film deposited at 5 h.

  17. Effects of deposition time in chemically deposited ZnS films in acidic solution

    International Nuclear Information System (INIS)

    We report an experimental study on the synthesis and characterization of zinc sulfide (ZnS) single layer thin films deposited on glass substrates by chemical bath deposition technique in acidic solution. The effect of deposition time on the microstructure, surface morphology, optical absorption, transmittance, and photoluminescence (PL) was investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM), UV-Vis–NIR spectrophotometry and photoluminescence (PL) spectroscopy. The results showed that the samples exhibit wurtzite structure and their crystal quality is improved by increasing deposition time. The latter, was found to affect the morphology of the thin films as showed by SEM micrographs. The optical measurements revealed a high transparency in the visible range and a dependence of absorption edge and band gap on deposition time. The room temperature PL spectra indicated that all ZnS grown thin films emit a UV and blue light, while the band intensities are found to be dependent on deposition times. - Highlights: • Single layer ZnS thin films were deposited by CBD in acidic solution at 95 °C. • The effect of deposition time was investigated. • Coexistence of ZnS and ZnO hexagonal structures for time deposition below 2 h • Thicker ZnS films were achieved after monolayer deposition for 5 h. • The highest UV-blue emission observed in thin film deposited at 5 h

  18. Research on depositing Ni45 alloy on titanium alloy surface by electrospark deposition

    Institute of Scientific and Technical Information of China (English)

    You Tao; Zhang Chunhui; Su Guiqiao; Yan Ping

    2008-01-01

    Taking Ni45 bar as electrode, a strengthened layer of thickness up to 50 pm was built up on BT20 titanium alloy matrix by means of electrospark deposition. Results of phase analysis by using of X-ray diffraction confirmed that the deposition layer was composed mostly of three phases, NiTi, NiTi2layer was up to 910 HV0.05, about 2.7 times as high as that of the matrix. The hardness at the cross-section of the entire deposition layer showed a gradient distribution. The effects of capacitance and deposition time on thickness of deposition layer were also studied, and results showed that with relatively low capacity and short deposition time the deposition layer without cracks can be obtained.

  19. The effect of fog on radionuclide deposition velocities

    International Nuclear Information System (INIS)

    Current nuclear power station release models do not evaluate deposition under foggy atmospheric conditions. Deposition velocities and scavenging coefficients of radioactive particles entrained in fog are presented for the Point Lepreau area of the Bay of Fundy coast. It is recommended to calculate deposition based on fog deposition velocities. The deposition velocities can be calculated from common meteorological data. The range of deposition velocities is approximately 1 - 100 cm/s. Fog deposition is surface roughness dependent with forests having larger deposition and deposition velocities than soil or grasses. (author)

  20. Industrial types of uranium deposits in Kazakhstan

    International Nuclear Information System (INIS)

    The main industrial uranium deposits of Kazakhstan that can be commercially mined, are located in two ore regions and are represented by two types of the uranium deposits. The first region is named Chu-Syrdarya (75.6% of total resources of Kazakhstan) and is located in the South of Kazakhstan and this one is the largest in the world among the regions of the deposits connected with the bed oxidation zone, localized in the permeable sediments and amenable for in-situ leach mining. The second region is named Kokshetau (16% of total resources) and is located in the North of Kazakhstan at the north edge of Kazak Shield and is characterized by the vein-stockwork type of deposit. Other industrial deposits (8.4% of total resources) are grouped in two regions that have been determined and are retained as reserves for economical and ecological reasons. These are: Pricaspian region with the organic phosphate type of uranium deposits; and Ili-Balkhash region with mainly the coal-uranium type. There are 44 industrial uranium deposits with resources ranging from 1000 t to 100000 t U and more in each of them, in all, in Kazakhstan. Seven of them are completely mined now. Total uranium resources in Kazakhstan are determined at 1670000 t U. (author)

  1. Regional and Localized Deposits on the Moon

    Science.gov (United States)

    Coombs, Cassandra R.

    1996-01-01

    Earth-based telescopic remote sensing studies have provided important information concerning lunar pyroclastic deposits. Combined with the returned lunar sample studies and analyses of lunar photography, we have learned a great deal about the nature and origin of these explosive volcanic materials. Lunar pyroclastic deposits are more numerous, extensive, and widely distributed than previously thought. Two generic classes of lunar pyroclastics have been identified, regional and localized. From the former, two separate spectral compositional groups have been identified; one is dominated by Fe(2+)-bearing glasses, the other is composed of ilmenite-rich black spheres. Comparatively, three separate spectral groups have been identified among the localized deposits: highlands-rich, olivine-rich, and mare-rich. Returned sample studies and the recently collected Galileo and Clementine data also corroborate these findings. Albedo data and multispectral imagery suggest that the thicker core deposits of the regional dark mantle deposits (RDMD) are surrounded by pyroclastic debris and subjacent highlands material. The presence of a major component of pyroclastic debris in the regolith surrounding the core regional deposits has important implications for the resource potential of these materials. Both telescopic and orbital spectra indicate that the regional pyroclastic deposits are rich in iron, titanium and oxygen-bearing minerals. Particle shapes vary from simple glass spheres to compound droplets with quench crystallized textures. Their small grain size and friability make them ideal indigenous feedstock. Compared to other resource feedstock sources on the Moon, these pyroclastic materials may be the best oxygen resource on the Moon.

  2. Reducing tube bundle deposition using alternative amines

    International Nuclear Information System (INIS)

    Particle deposition rates were measured in a high-temperature loop for magnetite and hematite depositing onto Inconel-600 under flow-boiling conditions with pH controlled, using one of the following amines: morpholine, ammonia, ethanolamine, or dimethylamine. Hematite particles deposited at rates 10 times greater than those measured for magnetite although the hematite deposition rate dropped when the loop was operated under reducing conditions. The magnetite deposition rate was influenced by the amine used to control the pH, with the relative rate decreasing in the following series: morpholine (1) : ethanolamine (0.72) : ammonia (0.51) dimethylamine (0.25). These trends in deposition rate are discussed in terms of the surface chemistry of the corrosion products. Deposition rates for both magnetite and hematite increased significantly once the mixture quality exceeded about 0.3, which may be related to a change in the heat-transfer mechanism from nucleate boiling to 2-phase forced-convection through a thin film. (author)

  3. Deposition of large particles in human lung

    International Nuclear Information System (INIS)

    Twenty-four nonsmoking males, all without history of pulmonary disease, were randomly divided into four groups of six subjects each. The subjects in each group inhaled monodisperse Teflon particles labelled with 111In (half-life 2.83 days); 8.2, 11.5, 13.7 and 16.4 micron aerodynamic diameter, respectively. Radioactivity in head and throat, lung and stomach was determined after 0, 3 and 24 hrs using a profile scanner. For some subjects radioactivity was also determined using a whole-body scanner at 3.5 and 24 hrs. After the 24-hr determination the subjects inhaled labelled Teflon particles again, this time with a filter in front of the mouth. Average values for total deposition in the body, obtained using a profile scanner, whole-body scanner and filter measurements, agreed fairly well. Lung retention values obtained by whole-body and profile scanning also agreed well. The average deposition in the lung, expressed as a percentage of total deposition, was 49, 31, 21 and 13% for the four particle sizes (8.2-16.4 micron). Alveolar deposition, determined as retention at 24 hrs and expressed in percent of total deposition, was 15, 4, 4 and 1%. For the smallest particle sizes the deposition values agreed with earlier investigations. However, for the larger particles the two deposition values were higher than expected when compared to earlier studies

  4. Deposition of large particles in human lung.

    Science.gov (United States)

    Svartengren, M; Falk, R; Linnman, L; Philipson, K; Camner, P

    1987-01-01

    Twenty-four nonsmoking males, all without history of pulmonary disease, were randomly divided into four groups of six subjects each. The subjects in each group inhaled monodisperse Teflon particles labelled with 111In (half-life 2.83 days); 8.2, 11.5, 13.7 and 16.4 micron aerodynamic diameter, respectively. Radioactivity in head and throat, lung and stomach was determined after 0, 3 and 24 hrs using a profile scanner. For some subjects radioactivity was also determined using a whole-body scanner at 3.5 and 24 hrs. After the 24-hr determination the subjects inhaled labelled Teflon particles again, this time with a filter in front of the mouth. Average values for total deposition in the body, obtained using a profile scanner, whole-body scanner and filter measurements, agreed fairly well. Lung retention values obtained by whole-body and profile scanning also agreed well. The average deposition in the lung, expressed as a percentage of total deposition, was 49, 31, 21 and 13% for the four particle sizes (8.2-16.4 micron). Alveolar deposition, determined as retention at 24 hrs and expressed in percent of total deposition, was 15, 4, 4 and 1%. For the smallest particle sizes the deposition values agreed with earlier investigations. However, for the larger particles the two deposition values were higher than expected when compared to earlier studies. PMID:3102217

  5. Deposition of large particles in human lung

    Energy Technology Data Exchange (ETDEWEB)

    Svartengren, M.; Falk, R.; Linnman, L.; Philipson, K.; Camner, P.

    1987-01-01

    Twenty-four nonsmoking males, all without history of pulmonary disease, were randomly divided into four groups of six subjects each. The subjects in each group inhaled monodisperse Teflon particles labelled with /sup 111/In (half-life 2.83 days); 8.2, 11.5, 13.7 and 16.4 micron aerodynamic diameter, respectively. Radioactivity in head and throat, lung and stomach was determined after 0, 3 and 24 hrs using a profile scanner. For some subjects radioactivity was also determined using a whole-body scanner at 3.5 and 24 hrs. After the 24-hr determination the subjects inhaled labelled Teflon particles again, this time with a filter in front of the mouth. Average values for total deposition in the body, obtained using a profile scanner, whole-body scanner and filter measurements, agreed fairly well. Lung retention values obtained by whole-body and profile scanning also agreed well. The average deposition in the lung, expressed as a percentage of total deposition, was 49, 31, 21 and 13% for the four particle sizes (8.2-16.4 micron). Alveolar deposition, determined as retention at 24 hrs and expressed in percent of total deposition, was 15, 4, 4 and 1%. For the smallest particle sizes the deposition values agreed with earlier investigations. However, for the larger particles the two deposition values were higher than expected when compared to earlier studies.

  6. Reducing tube bundle deposition with alternative amines

    International Nuclear Information System (INIS)

    Particle deposition rates have been measured in a high-temperature loop for magnetite and hematite depositing onto Inconel-600 under flow-boiling conditions with pH controlled using one of the following amines: morpholine, ammonia, ethanolamine, or dimethylamine. Hematite particles deposited at rates an order of magnitude greater than those measured for magnetite, although the hematite deposition rate dropped when the loop was operated under reducing conditions. The magnetite deposition rate was influenced by the amine used to control the pH, with the relative rate decreasing in the following series: morpholine (1) : ethanolamine (0.72) ammonia (0.51) : dimethylamine (0.25). These trends in deposition rate are discussed in terms of the surface chemistry of the corrosion products. Deposition rates for both magnetite and hematite increased significantly once the mixture quality exceeded about 0.3, which may be related to a change in the heat transfer mechanism from nucleate boiling to two-phase forced convection through a thin film. (author)

  7. ITO deposited by pyrosol for photovoltaic applications

    International Nuclear Information System (INIS)

    The goal of this work is to investigate morphology, electrical and optical properties of indium-tin-oxide (ITO) deposited by pyrosol on glass and Si substrates at different temperatures and to implement such layers for the processing of Si-based solar cells. The influence of the methanol/H2O ratio on general properties of ITO was investigated. Atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission spectra, ellipsometry and resistivity measurements were used for the analysis. It is shown that properties of ITO layers depend dramatically on the substrate used. It is shown that the resistivity of ITO layers deposited on a glass substrate is higher up to 2.5 times, compared to that of ITO layers deposited on a Si substrate at the same conditions, but in both cases decreases if the deposition temperature increases. Moreover, ITO layers deposited on a glass substrate are more flat and their refractive indexes are always lower for all deposition temperatures. An increase of the H2O concentration in a film-forming solution leads to a decrease of the ITO film resistivity and to a slight increase of the roughness. An application of pyrosol deposited ITO films as the top transparent electrodes for the (p+nn+)Si and heterojunction ITO/n-Si solar cells is demonstrated

  8. Dust deposits on Mars: The 'parna' analog

    Science.gov (United States)

    Greeley, Ronald; Williams, Steven H.

    1994-01-01

    Parna is an Autralian aboriginal word meaning 'sandy dust'. It has been applied to deposits of clay, silt, and sand which were initially transported by the wind as aggregates, or pellets, of sand size. Parna is distinguished by its silt and clay content, which in some cases exceeds 85% of the total volume of the deposit. Much of the fine-grained playa silt and clay is incorporated into the parna as sand-sized aggregates, which greatly facilitate their transportation and reworking by the wind. Rain following aggregate emplacement can cause their disintegration, rendering the parna immobile by the wind, yet some pellets can survive several wetting/drying episodes. Parna deposits on Earth occur both as dune forms and as sheet deposits which mantle older terrains. In both cases the deposits are typically derived from lacustrine (lake) beds, such as playas. There is substantial evidence to suggest that bodies of water existed on Mars in the past. Thus, the potential is high for lacustrine deposits and the formation of parna on Mars. Although no parna dunes have been identified, it is suggested that the deposits derived from White Rock (-8 deg, 335 deg W), near Mamers Valles (34 deg, 343 deg W), and elsewhere on Mars may represent sheet parna. Data obtained from Mars-94/96 missions and potential landed spacecraft may provide additional evidence for the existence of parna on Mars.

  9. Dust deposits on Mars: The 'parna' analog

    Science.gov (United States)

    Greeley, Ronald; Williams, Steven H.

    1994-07-01

    Parna is an Australian aboriginal word meaning 'sandy dust'. It has been applied to deposits of clay, silt, and sand which were initially transported by the wind as aggregates, or pellets, of sand size. Parna is distinguished by its silt and clay content, which in some cases exceeds 85% of the total volume of the deposit. Much of the fine-grained playa silt and clay is incorporated into the parna as sand-sized aggregates, which greatly facilitate their transportation and reworking by the wind. Rain following aggregate emplacement can cause their disintegration, rendering the parna immobile by the wind, yet some pellets can survive several wetting/drying episodes. Parna deposits on Earth occur both as dune forms and as sheet deposits which mantle older terrains. In both cases the deposits are typically derived from lacustrine (lake) beds, such as playas. There is substantial evidence to suggest that bodies of water existed on Mars in the past. Thus, the potential is high for lacustrine deposits and the formation of parna on Mars. Although no parna dunes have been identified, it is suggested that the deposits derived from White Rock (-8 deg, 335 deg W), near Mamers Valles (34 deg, 343 deg W), and elsewhere on Mars may represent sheet parna. Data obtained from Mars-94/96 missions and potential landed spacecraft may provide additional evidence for the existence of parna on Mars.

  10. Structural characterization of MAPLE deposited lipase biofilm

    Science.gov (United States)

    Aronne, Antonio; Ausanio, Giovanni; Bloisi, Francesco; Calabria, Raffaela; Califano, Valeria; Fanelli, Esther; Massoli, Patrizio; Vicari, Luciano R. M.

    2014-11-01

    Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography-mass spectrometry gave results consistent with undamaged deposition of lipase.

  11. TEOS-based oxides: deposition dependent properties

    International Nuclear Information System (INIS)

    This paper reports the effects of three important parameters, deposition temperature, TEOS concentration and RF power in the plasma enhanced CVD of TEOS-based oxides on the resulting film characteristics such as impurity incorporation, film density, moisture absorption, intrinsic and thermal stresses. Ion-bombardment induced desorption of reactive precursor species is suggested to occur under certain conditions. Further, it is shown that the film properties continue to evolve until the film thickness exceeds 3000A. For 1 μm films deposited using typical settings of deposition parameters, the average TCE is estimated to be 0.9 ppm/ C using the stress-temperature characteristics. (orig.)

  12. Magnetoresistive multilayers deposited on the AAO membranes

    Energy Technology Data Exchange (ETDEWEB)

    Malkinski, Leszek M. [Advanced Materials Research Institute, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148 (United States)]. E-mail: lmalkins@uno.edu; Chalastaras, Athanasios [Advanced Materials Research Institute, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148 (United States); Vovk, Andriy [Advanced Materials Research Institute, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148 (United States); Jung, Jin-Seung [Department of Chemistry, Kangnung National University, Kangnung 210702 (Korea, Republic of) ; Kim, Eun-Mee [Department of Chemistry, Kangnung National University, Kangnung 210702 (Korea, Republic of) ; Jun, Jong-Ho [Department of Applied Chemistry, Kunkuk University, Chungju 151747 (Korea, Republic of) ; Ventrice, Carl A. [Advanced Materials Research Institute, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148 (United States)

    2005-02-01

    Silicon and GaAs wafers are the most commonly used substrates for deposition of giant magnetoresistive (GMR) multilayers. We explored a new type of a substrate, prepared electrochemically by anodization of aluminum sheets, for deposition of GMR multilayers. The surface of this AAO substrate consists of nanosized hemispheres organized in a regular hexagonal array. The current applied along the substrate surface intersects many magnetic layers in the multilayered structure, which results in enhancement of giant magnetoresistance effect. The GMR effect in uncoupled Co/Cu multilayers was significantly larger than the magnetoresistance of similar structures deposited on Si.

  13. Geochemistry and deposit exploration of uranium

    International Nuclear Information System (INIS)

    On the basis of genetically simplified earth crust profiles and a mining synoptic table the broad outlines of the enrichment processes are shown, from geochemical dilution to workable deposits for the major uranium ore deposits. Characteristics are offered of the physical-chemical data of different genetic environments, the tectonic preconditions for ready mobilisation of uranium in the form of uranyl complexes with U6+ and the preferred fixing of U4+ minerals in reducing facies; these cover both intracrustal deposit formations, surface circulation and metamorphesis. (orig.)

  14. Thermodynamic analysis and deposition of refractory materials

    International Nuclear Information System (INIS)

    This article does not pretend to be an exhaustive review of all publications in which a thermodynamic analysis has been used to analyse the chemical vapour deposition of refractory materials. It simply covers a certain number of experiments in which the present authors made use of various aspects of this method: overall or partial optimization of a process, determination of the deposition material most suited to fulfilling a given role and approach to mechanisms governing the chemical deposition reaction. A thermodynamic analysis is presented here from a more unusual angle, by examples of localized and varied intervention, in order to demonstrate the multiple uses of the method. (orig.)

  15. Residual stresses in tungsten vapor deposits

    International Nuclear Information System (INIS)

    Using circular specimens values and distribution of peripheral residual stresses in deposits of gaseous tungsten of different thickness on a graphite substrate were determined by the Davidenkov method during electrolytic re oval of metal layers. It is established that the thinner is the deposit the lower is the level of arisnng stresses. After annealing at 750 deg C the stresses decrease by approximately 30 %, and annealing at 1500 deg C results in minimum values. It is assumed that the decrease of the stresses after nnealing at 1500 deg C results from the variations in deposit substructure typical for polygonization processes

  16. Deposition of thin films of multicomponent materials

    Science.gov (United States)

    Thakoor, Sarita (Inventor)

    1993-01-01

    Composite films of multicomponent materials, such as oxides and nitrides, e.g., lead zirconate titanate, are deposited by dc magnetron sputtering, employing a rotating substrate holder, which rotates relative to a plurality of targets, one target for each metal element of the multicomponent material. The sputtering is carried out in a reactive atmosphere. The substrates on which the layers are deposited are at ambient temperature. Following deposition of the composite film, the film is heated to a temperature sufficient to initiate a solid state reaction and form the final product, which is substantially single phase and substantially homogeneous.

  17. Deposition and microstructure of pyrolytic carbon

    International Nuclear Information System (INIS)

    Two kinds of experiment concerning pyrolytic carbon deposition have been carried out. In one experiment, an attempt was made to coat alumina particles as well as buffer-coated UO2 particle with pyrolytic carbon of laminar structure by means of a fluidized bed technique. Benzene was used as the carbon source and the temperature was 10000C. In the other experiment, carbon deposition was made on graphite surface. Possibility was tested to obtain uniform coating along the direction of gas stream. Carbon source, in this case, was mainly n-hexane and the temperature ranged 750 -- 8500C. Microstructure of the deposit was studied in both experiments. (author)

  18. Hybrid fall deposits in the Bishop Tuff, California: A novel pyroclastic depositional mechanism

    Science.gov (United States)

    Wilson, Colin J. N.; Hildreth, Wes

    1998-01-01

    Hybrid fall deposits in the Bishop Tuff show features common to both archetypal fall and surge deposits. Like normal-fall deposits, they have an overall plane-parallel bedding and flat-lying pumice clasts but also, like surge deposits, they show variable development of cross-bedding, some crystal and pumice sorting, and some rounding of pumice clasts. All variations exist from normal-fall deposits, through streaky material with incipient development of cross-bedding, to the hybrid fall deposits with well-developed cross-bedding. The streaky and hybrid deposits are interpreted as fall material contemporaneously redeposited by strong (up to 40 m/s) swirling winds, comparable to firestorm whirlwinds, generated by air currents associated with coeval emplacement of pyroclastic flows. Recognition of hybrid fall deposits is important in interpreting the dynamics of explosive eruptions and correctly assessing volcanic hazards. However, although such deposits may be commonly produced by explosive eruptions, especially where pyroclastic flows accompany fall activity, they are likely to be overlooked, or wrongly interpreted as surge deposits or secondary, reworked material.

  19. Platinum-ruthenium bimetallic clusters on graphite: a comparison of vapor deposition and electroless deposition methods.

    Science.gov (United States)

    Galhenage, Randima P; Xie, Kangmin; Diao, Weijian; Tengco, John Meynard M; Seuser, Grant S; Monnier, John R; Chen, Donna A

    2015-11-14

    Bimetallic Pt-Ru clusters have been grown on highly ordered pyrolytic graphite (HOPG) surfaces by vapor deposition and by electroless deposition. These studies help to bridge the material gap between well-characterized vapor deposited clusters and electrolessly deposited clusters, which are better suited for industrial catalyst preparation. In the vapor deposition experiments, bimetallic clusters were formed by the sequential deposition of Pt on Ru or Ru on Pt. Seed clusters of the first metal were grown on HOPG surfaces that were sputtered with Ar(+) to introduce defects, which act as nucleation sites for Pt or Ru. On the unmodified HOPG surface, both Pt and Ru clusters preferentially nucleated at the step edges, whereas on the sputtered surface, clusters with relatively uniform sizes and spatial distributions were formed. Low energy ion scattering experiments showed that the surface compositions of the bimetallic clusters are Pt-rich, regardless of the order of deposition, indicating that the interdiffusion of metals within the clusters is facile at room temperature. Bimetallic clusters on sputtered HOPG were prepared by the electroless deposition of Pt on Ru seed clusters from a Pt(+2) solution using dimethylamine borane as the reducing agent at pH 11 and 40 °C. After exposure to the electroless deposition bath, Pt was selectively deposited on Ru, as demonstrated by the detection of Pt on the surface by XPS, and the increase in the average cluster height without an increase in the number of clusters, indicating that Pt atoms are incorporated into the Ru seed clusters. Electroless deposition of Ru on Pt seed clusters was also achieved, but it should be noted that this deposition method is extremely sensitive to the presence of other metal ions in solution that have a higher reduction potential than the metal ion targeted for deposition. PMID:26018140

  20. Properties of carbon deposits on tungsten nano-structure

    International Nuclear Information System (INIS)

    C deposition characteristics on W nano-structure by two different deposition methods are investigated to study C deposition mechanisms on W nano-structure and its characteristics. The two methods were as follows: irradiation by mixed D and C ion beam, and deposition by magnetron sputtering. Differences on deposition condition such as deposition temperature, incident species and energy affected properties of C deposits. Structure of C deposits was investigated by SEM and Raman spectroscopy. D retention properties were investigated by thermal desorption spectroscopy. It was found that C deposits on nano-structured surface have low internal stress and porous structure compared with C deposits on flat surfaces. Increase of CD4 release from C deposition layers on nano-structured surface was investigated by TDS. These results showed the effects of nano-structure on structure and thermal desorption properties of C deposits

  1. The neutron characteristics of coal deposits

    International Nuclear Information System (INIS)

    The neutron parameters of coal vs. its hydrogen content are calculated. The strong dependences observed point the possibilities of neutron analytical methods for determining hydrogen content in coal deposits. (author)

  2. Contacting cadmium deposition from spent industrial solutions

    International Nuclear Information System (INIS)

    Cadmium metal deposition from spent industrial solutions by cadmium (2) reduction with dispersed aluminium is studied. The influence of temperature, reagent concentration and the presence of complexing agents on the yield and purity of isolated cadmium metal is examined

  3. Porphyry copper deposits of the world

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Information on porphyry copper deposits from around the world with grade and tonnage models, a general classification based on geologic setting, mineralogy, with...

  4. ROE Wet Nitrate Deposition 1989-1991

    Data.gov (United States)

    U.S. Environmental Protection Agency — The raster data represent the amount of wet nitrate deposition in kilograms per hectare from 1989 to 1991. Summary data in this indicator were provided by EPA’s...

  5. ROE Wet Sulfate Deposition 2009-2011

    Data.gov (United States)

    U.S. Environmental Protection Agency — The raster data represent the amount of wet sulfate deposition in kilograms per hectare from 2009 to 2011. Summary data in this indicator were provided by EPA’s...

  6. Oscillations in Electrochemical Deposition of Zinc

    Science.gov (United States)

    Wang, Sheng; Zhang, Ke-Qin; Xu, Qing-Yu; Wang, Mu; Peng, Ru-Wen; Zhang, Ze; Ming, Nai-ben

    2003-06-01

    In this article we report the systematic studies on the oscillation of contrast in front of a growing zinc dendrite in electrochemical deposition observed with interference contrast microscopy. The dependence of the oscillation frequency on the experimental conditions, such as the electric current, the resistance of ion transfer, pH of the electrolyte and the tilting of the electrodeposition cell, etc., has been investigated. The microstructures of the electrodeposits are analyzed with transmission electron microscopy. We conclude that the contrast oscillation in front of the zinc deposit is indeed associated with the concentration oscillation, and is synchronized with the electric voltage/current signals. Although the oscillation can be affected by mass transport in the system, we suggest that it roots from the alternating deposition of zinc and zinc hydroxide on the deposit-electrolyte interface.

  7. Rare earth element mines, deposits, and occurrences

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset contains location, geologic and mineral economic data for world rare earth mines, deposits, and occurrences. The data in this compilation were derived...

  8. NOAA/WDC Global Tsunami Deposits Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Discover where, when and how severely tsunamis affected Earth in geologic history. Information regarding Tsunami Deposits and Proxies for Tsunami Events complements...

  9. ROE Total Nitrogen Deposition 1989-1991

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset identifies the amount of wet, dry, and total deposition of nitrogen in kilograms per hectare from 1989 to 1991 at a set of point locations across the...

  10. DLC films deposited by DC PACVD method

    International Nuclear Information System (INIS)

    In this paper the deposition of DLC coating by direct current PACVD (DC PACVD) is presented. DLC films were deposited on silicon (111) and steel substrates. The steel substrate consists of 0.9 % - C, 4.14% - Cr, 6.1% - W, 5% - Mo, 2.02% - V. These samples were polished up to a mirror finish using series of standard metallurgical polishing steps. The apparatus for plasma assisted chemical vapor deposition consisted of vacuum chamber, diffusion pump, two parallel electrodes and generator of DC discharge plasma. We deposited DLC films on our substrates with the same parameters, but one, which was changed. The microhardness of the coated materials is higher than the base material about 13 GPa at the load 50 mN and bias voltage -900 V. (Authors)

  11. Stability of nanocrystalline electrochemically deposited layers

    DEFF Research Database (Denmark)

    Pantleon, Karen; Somers, Marcel A. J.

    2009-01-01

    The technological demand for manufacturing components with complex geometries of micrometer or sub-micrometer dimensions and ambitions for ongoing miniaturization have attracted particular attention to electrochemical deposition methods. Thin layers of electrochemically deposited metals and alloys...... have different microstructure and properties compared to bulk materials and the thermodynamic non-equilibrium state of as-deposited layers frequently results in changes of the microstructure as a function of time and/or temperature. The evolving microstructure affects the functionality and reliability...... of electrodeposited components, which can be beneficial, as for the electrical conductivity of copper interconnect lines, or detrimental, as for reduced strength of nickel in MEMS applications. The present work reports on in-situ studies of the microstructure stability of as-deposited nanocrystalline...

  12. ROE Total Nitrogen Deposition 2011-2013

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset identifies the amount of wet, dry, and total deposition of nitrogen in kilograms per hectare from 2011 to 2013 at a set of point locations across the...

  13. ROE Total Sulfur Deposition 1989-1991

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset identifies the amount of wet, dry, and total deposition of sulfur in kilograms per hectare from 1989 to 1991 at a set of point locations across the...

  14. Dikes and mineralization in uraniferous apatite deposits

    International Nuclear Information System (INIS)

    The problem of the age relationships between dike bodies and the mineralization in deposits of uraniferous apatites in carbonate rocks is reconsidered. The post-ore history of apatite mineralization reveals a combination of polygenic mineral associations

  15. Major mineral deposits of the world

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Regional locations and general geologic setting of known deposits of major nonfuel mineral commodities. Originally compiled in five parts by diverse authors,...

  16. Hard carbon films: Deposition and diagnostics

    OpenAIRE

    Frgala Zdeněk; Kudrle Vít; Janča Jan; Meško Marcel; Eliáš Marek; Buršík Jiří

    2003-01-01

    We studied the growth of microcrystalline diamond films on pre-treated Si and WC-Co substrates by microwave plasma chemical vapour deposition (MPCVD). The pre-treatment was varied and its effect on diamond film was studied.

  17. Perovskite Thin Films via Atomic Layer Deposition

    KAUST Repository

    Sutherland, Brandon R.

    2014-10-30

    © 2014 Wiley-VCH Verlag GmbH & Co. KGaA. (Graph Presented) A new method to deposit perovskite thin films that benefit from the thickness control and conformality of atomic layer deposition (ALD) is detailed. A seed layer of ALD PbS is place-exchanged with PbI2 and subsequently CH3NH3PbI3 perovskite. These films show promising optical properties, with gain coefficients of 3200 ± 830 cm-1.

  18. Fabrication of Micro Components by Electrochemical Deposition

    DEFF Research Database (Denmark)

    Tang, Peter Torben

    The main issue of this thesis is the combination of electrochemical deposition of metals and micro machining. Processes for electroplating and electroless plating of nickel and nickel alloys have been developed and optimised for compatibility with microelectronics and silicon based micromechanics...... of electrochemical machining and traditional machining is compared to micro machining techniques as performed in the field of microelectronics. Various practical solutions and equipment for electrochemical deposition of micro components are demonstrated, as well as the use and experience obtained...

  19. Making Lightweight Structures By Vapor Deposition

    Science.gov (United States)

    Goela, Jitendra S.; Pickering, Michael A.; Taylor, Raymond L.

    1990-01-01

    Technique developed for fabrication of stiff, strong, lightweight structures of silicon carbide or other materials by any of several deposition processes. Structures made by method can have complicated shapes. Ability to manufacture complex shape from pure deposited SiC useful and leads to new products in several fields. These lightweight structures used as backup structures for optical components, as structural components in automotive, aerospace, and outer space applications, and as lightweight parts of furniture for outer space.

  20. A Game Theory Approach of Deposit Insurance

    Institute of Scientific and Technical Information of China (English)

    JIANG Hong-xun; QIU Wan-hua; MING Ming

    2002-01-01

    This paper presents a dynamic game theory approach for deposit insurance. We formulate a deposit insurance problem as an incomplete information game theory model, which deduces the expression of Capital Charge Ratio for national central bank. The main contribution of the paper however is that we then extrapolate the declared value of the bank in best its policy. Finally a numerical example is used to illustrate the approach proposed in this paper.

  1. Removal of External Deposits on Boiler Tubes

    Directory of Open Access Journals (Sweden)

    C. P. De

    1970-07-01

    Full Text Available The superheater tubes in Port and Starboard boilers were found to have completely clogged by heavy deposits, which on analysis mainly vanadium pentoxide and sodium sulphmatter. The cleaning of the deposits was accomplished by alternate spraying with 15-20 per cent hydrogen peroxide and washing with hot water jets. Over the past two years, since the date of cleaning, the IN ship is operating without any trouble in the boilers.

  2. Selective Electroless Silver Deposition on Graphene Edges

    DEFF Research Database (Denmark)

    Durhuus, D.; Larsen, M. V.; Andryieuski, Andrei;

    2015-01-01

    We demonstrate a method of electroless selective silver deposition on graphene edges or between graphene islands without covering the surface of graphene. Modifications of the deposition recipe allow for decoration of graphene edges with silver nanoparticles or filling holes in damaged graphene...... on silica substrate and thus potentially restoring electric connectivity with minimal influence on the overall graphene electrical and optical properties. The presented technique could find applications in graphene based transparent conductors as well as selective edge functionalization and can be extended...

  3. Theoretical and Economic Aspects of Deposit Insurance

    OpenAIRE

    Zbyněk Revenda

    2013-01-01

    The paper deals with deposit insurance schemes as an integral part of the present system of the banking regulation. Insurance premiums, limits and the rates of compensation and consequences of deposit insurance are then discussed from the theoretical and practical points of view. The moral hazard of banks and depositors and adverse selection are the main undesirable accompanying effects, which are directly connected with the scale of insurance protection in banks. The European Union unifi es ...

  4. Study on pulsed excimer laser deposited films

    CERN Document Server

    Liu Jing Ru; Li Tie Jun; Yao Dong Sheng; Wang Li Ge; Yuan Xiao; Wang Sheng; Ye Xi Sheng

    2002-01-01

    Pulsed lasers of two different durations (30 ns, 500 fs) are used to deposit Hydrogen-free Diamond Like Carbon (DLC) films over large areas. Analysis of DLC films shows remarkable mechanical, optical, electrical, and chemical properties that are close to those of diamond. By optical emission spectroscopy and ion probe, the effects of plasma characteristic on DLC film are on experimentally studied. Amorphous silicon films deposited by PLD are also experimentally studied

  5. Thin film deposition with time varying temperature

    OpenAIRE

    de Assis, T. A.; Reis, F. D. A. A.

    2013-01-01

    We study the effects of time-dependent substrate/film temperature in the deposition of a mesoscopically thick film using a statistical model that accounts for diffusion of adatoms without lateral neighbors whose coefficients depend on an activation energy and temperature. Dynamic scaling with fixed temperature is extended to predict conditions in which the temperature variation significantly affects surface roughness scaling. It agrees with computer simulation results for deposition of up to ...

  6. IMMUNOGLOBULIN DEPOSITIONS IN PERIPHERAL NERVES IN POLYMYOSITIS

    Institute of Scientific and Technical Information of China (English)

    李越星; 陈清棠; 吴丽娟; 贾钟; 张秋荣; 左越焕

    1995-01-01

    An immunocytochemical study was performed in 6 peripheral nerve specimens from 6 cases of polymyositis.The results revealed that depositions of IgG,IgM,IgA and C3 were found in the epineurium,perineurium and the walls of capillaries.These findings demonstrated that depositions of immonoglobulins and the complement-mediated immunoreaction may play an important role in pathogenesis of polymyositis with peripheral nerfve involvements.

  7. Modelling The Dynamic Distribution Of Spray Deposits

    OpenAIRE

    Lebeau, Frédéric

    2004-01-01

    A mathematical model to estimate the spray distribution of phytopharmaceutical deposits under a spray boom is proposed. It focuses on the need to take account of the dynamic effects of the forward movement of the boom. These are related both to the horizontal and vertical boom movement and to the influence of aerodynamic factors on the nozzle spray distribution. The distribution of the spray deposits is computed by multiplying the nozzle spray pattern by the time needed to m...

  8. Deposition and Characterisation of Crystalline Silicon

    OpenAIRE

    Rachow, Thomas

    2014-01-01

    In this thesis, crystalline silicon thin films by atmospheric pressure chemical vapour deposition have been studied. These silicon films can be deposited on silicon wafers or transferred to various substrates for photovoltaic applications. One of the main advantages is the flexibility in thickness and doping concentration which allows the application of the silicon thin films in various solar cell concepts. The combination of these films with an industrial solar cell fabrication process has a...

  9. ECONOMIC GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>20102338 Cheng Jialong(China University of Geosciences,Wuhan 430074,China);Zhao Yongxin Summary of Metallogenic,Geochemical Study on the Skarn Deposits(Contributions to Geology and Mineral Resources Research,ISSN1001-1412,CN12-1131/P,24(4),2009,p.329-334,358,2 illus.,40 refs.)Key words:skarn depositRecent study shows that the skarn deposit not only occurs in the contact between the intermediate-acidic intrusion and carbonate rocks but also in the contact of the basic intrusion or in the distal strata,not only hosted by the carbonate rocks but also by the active volcanic sedimentary rocks,such as the volcanic sedimentary tuff.The vast majority of skarn deposits are related to magmatic arcs in the subduction zone beneath the continental crust with the mesothermal to epithermal ore-forming temperature and the shallow to medium ore-forming depth.The abyssal environment is not favorable for the formation of skarn.Ore materials of the skarn deposit mainly come from deep source with partial crust materials involved.20102339 Chi Guoxiang(Department of Geology,University of Regina,Regina,Saskatchewan S4SOA2,Canada);Lai Jianqing Roles of Fluid Inclusions in Study of Mineral Deposits(Mineral Deposits,ISSN0258-7106,CN11-1965/P,28(6),2009,p.850-855,36 refs.,with English abstract)Key words:fluid inclusions,ore-forming fluids20102340 Ding Jianhua(Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China);Xiao Keyan Large Scale Mineral Assessment in Three Di

  10. Impact of sludge deposition on biodiversity.

    Science.gov (United States)

    Manzetti, Sergio; van der Spoel, David

    2015-11-01

    Sludge deposition in the environment is carried out in several countries. It encompasses the dispersion of treated or untreated sludge in forests, marsh lands, open waters as well as estuarine systems resulting in the gradual accumulation of toxins and persistent organic compounds in the environment. Studies on the life cycle of compounds from sludge deposition and the consequences of deposition are few. Most reports focus rather on treatment-methods and approaches, legislative aspects as well as analytical evaluations of the chemical profiles of sludge. This paper reviews recent as well as some older studies on sludge deposition in forests and other ecosystems. From the literature covered it can be concluded that sludge deposition induces two detrimental effects on the environment: (1) raising of the levels of persistent toxins in soil, vegetation and wild life and (2) slow and long-termed biodiversity-reduction through the fertilizing nutrient pollution operating on the vegetation. Since recent studies show that eutrophication of the environment is a major threat to global biodiversity supplying additional nutrients through sludge-based fertilization seems imprudent. Toxins that accumulate in the vegetation are transferred to feeding herbivores and their predators, resulting in a reduced long-term survival chance of exposed species. We briefly review current legislation for sludge deposition and suggest alternative routes to handling this difficult class of waste. PMID:26318179

  11. Modeling sediment deposition from marine outfall jets.

    Science.gov (United States)

    Terfous, Abdelali; Chiban, Samia; Ghenaim, Abdellah

    2016-08-01

    This paper presents a two-dimensional model to study the sediment deposition from marine outfall jets. The introduced unidirectional coupling (fluid-sediment) is an appropriate choice in the case of low-concentrated particle-laden jets such as municipal wastewater discharge, where the concentration of particles is small enough and does not affect the hydrodynamic development of the jet in the nearfield. The sedimentation model takes advantage of the preferential concentration phenomenon. The deposition criterion states that the deposition of sediments begins when the vertical component of the entrainment velocity becomes smaller than the settling velocity. Once the deposition process begins, it is controlled by the settling velocity, entrainment velocity, volume flux, and sediment concentration. The deposition along the jet trajectory is expressed by an ordinary differential equation coupled with the liquid phase equations. Experiments of Lane-Serff and Moran [Sedimentation from Buoyant jets. J Hyd Eng. 2005;131(3):166-174], Cuthbertson and Davies [Deposition from particle-laden, round, turbulent, horizontal, buoyant jets in stationary and coflowing receiving fluids. J Hydr Eng. 2008;134(4):390-402], and Lee [Mixing of horizontal sediment laden jets [dissertation]. Hong Kong: University of Hong Kong; 2010], chosen from bibliography, are used to validate the model. These experiments cover the cases of horizontal and inclined buoyant jets in stationary ambient, horizontal buoyant jets in co-flow current and nonbuoyant horizontal jets in stationary ambient. Good agreement between the experiments and the obtained simulations is revealed. PMID:26732467

  12. Crud deposition on fuel in WWER reactors

    International Nuclear Information System (INIS)

    Reliability of nuclear fuel and radiation fields surrounding primary systems are important aspects of overall nuclear reactor safety. Corrosion product (crud) deposition on fuel surfaces has implications for fuel performance through heat transfer and local chemistry modifications. Crud is currently one of the key industry issues and has been implicated in several recent cases of crud-related fuel failures and core plugging. Activated crud is deposited on out-of-core surfaces, mainly steam generators, resulting in high radiation fields and high doses of plant staff. Due to radiation build-up in primary circuit systems, decontamination of primary systems components and steam generators is used. Several issues involving decontamination were observed in some cases. After decontamination higher corrosion product release occurs followed by subsequent crud deposition on fuel surfaces. The paper summarizes experience with water chemistry and decontamination that can influence crud deposition on fuel surfaces. The following areas are discussed: 1) Experience with crud deposition, primary water chemistry and decontamination under operating conditions; 2) The behaviour of organic compounds in primary coolant and on fuel surfaces; 3) A proposed experimental programme to study crud deposition. (authors)

  13. Atmospheric deposition fluxes to Monetary Bay

    Science.gov (United States)

    Gray, E.; Paytan, A.; Ryan, J.

    2008-12-01

    Atmospheric deposition has been widely recognized as a source of pollutants and nutrients to coastal ecosystems. Specifically, deposition includes nitrogen compounds, sulfur compounds, mercury, pesticides, phosphate, trace metals and other toxic compounds that can travel great distances. Sources of these components include both natural (volcanoes, mineral dust, forest fires) and anthropogenic (fossil fuels, chemical byproducts, incineration of waste) sources, which may contribute to harmful health and environmental impacts such as eutrophication, contaminated fish and harmful algal blooms. This study looks at the flux of aerosol deposition (TSP - total suspended particle load) to Monterey Bay, California. Samples are collected on a cascade impactor aerosol sampler (size fractions PM 2.5 and PM 10) every 48 hours continuously. Preliminary results indicate that the TSP for PM 10 ranged from 0.026 to 0.104 mg m-3 of air and for PM 2.5 from 0.014 to 0.046 mg m-3 of air. Using a deposition velocity of 2 cm s-1 for the large fraction (PM10 - PM 2.5) and a deposition velocity of 0.7 cm s-1 for the fine fraction (PM 2.5) deposition rates are 13 and 86 mg m-2 d-1 respectively.

  14. Deposition uniformity inspection in IC wafer surface

    International Nuclear Information System (INIS)

    This paper focuses on the task of automatic visual inspection of color uniformity on the surface of integrated circuits (IC) wafers arising from the layering process. The oxide thickness uniformity within a given wafer with a desired target thickness is of great importance for modern semiconductor circuits with small oxide thickness. The non-uniform chemical vapor deposition (CVD) on a wafer surface will proceed to fail testing in Wafer Acceptance Test (WAT). Early detection of non-uniform deposition in a wafer surface can reduce material waste and improve production yields. The fastest and most low-priced inspection method is a machine vision-based inspection system. In this paper, the proposed visual inspection system is based on the color representations which were reflected from wafer surface. The regions of non-uniform deposition present different colors from the uniform background in a wafer surface. The proposed inspection technique first learns the color data via color space transformation from uniform deposition of normal wafer surfaces. The individual small region statistical comparison scheme then proceeds to the testing wafers. Experimental results show that the proposed method can effectively detect the non-uniform deposition regions on the wafer surface. The inspection time of the deposited wafers is quite compatible with the atmospheric pressure CVD time

  15. Plasma deposited fluorinated films on porous membranes

    Energy Technology Data Exchange (ETDEWEB)

    Gancarz, Irena [Department of Polymer and Carbon Materials, Wrocław University of Technology, 50-370 Wrocław (Poland); Bryjak, Marek, E-mail: marek.bryjak@pwr.edu.pl [Department of Polymer and Carbon Materials, Wrocław University of Technology, 50-370 Wrocław (Poland); Kujawski, Jan; Wolska, Joanna [Department of Polymer and Carbon Materials, Wrocław University of Technology, 50-370 Wrocław (Poland); Kujawa, Joanna; Kujawski, Wojciech [Nicolaus Copernicus University, Faculty of Chemistry, 7 Gagarina St., 87-100 Torun (Poland)

    2015-02-01

    75 KHz plasma was used to modify track etched poly(ethylene terephthalate) membranes and deposit on them flouropolymers. Two fluorine bearing monomers were used: perflourohexane and hexafluorobenzene. The modified surfaces were analyzed by means of attenuated total reflection infra-red spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy and wettability. It was detected that hexaflourobenxene deposited to the larger extent than perflourohaxane did. The roughness of surfaces decreased when more fluoropolymer was deposited. The hydrophobic character of surface slightly disappeared during 20-days storage of hexaflourobenzene modified membrane. Perfluorohexane modified membrane did not change its character within 120 days after modification. It was expected that this phenomenon resulted from post-reactions of oxygen with radicals in polymer deposits. The obtained membranes could be used for membrane distillation of juices. - Highlights: • Plasma deposited hydrophobic layer of flouropolymers. • Deposition degree affects the surface properties. • Hydrohilization of surface due to reaction of oxygen with entrapped radicals. • Possibility to use modified porous membrane for water distillation and apple juice concentration.

  16. Quantitative analysis of diamond deposition reactor efficiency

    International Nuclear Information System (INIS)

    Graphical abstract: Surface H atom densities in a diamond deposition plasma reactor and the highest predicted value (black line). A 350 μm diamond crystal grown at 70 μm/h. Highlights: ► Electron temperature measurement at high pressure in diamond deposition reactor. ► H-atom density measurements at high pressure and high power in diamond deposition reactor. ► Surface H-atom density measurements at high pressure and high power in diamond deposition reactor. ► Microwave cavity based reactor efficiency compared to others reactors. - Abstract: Optical emission spectroscopy has been used to characterize diamond deposition microwave chemical vapour deposition (MWCVD) plasmas operating at high power density. Electron temperature has been deduced from H atom emission lines while H-atom mole fraction variations have been estimated using actinometry technique, for a wide range of working conditions: pressure 25–400 hPa and MW power 600–4000 W. An increase of the pressure from 14 hPa to 400 hPa with a simultaneous increase in power causes an electron temperature decrease from 17,000 K to 10,000 K and a H atom mole fraction increase from 0.1 to up to 0.6. This last value however must be considered as an upper estimate due to some assumptions made as well as experimental uncertainties.

  17. As-grown magnesium diboride superconducting thin films deposited by pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Grassano, G.; Ramadan, W.; Ferrando, V.; Bellingeri, E.; Marre, D.; Ferdeghini, C.; Grasso, G.; Putti, M.; Chincarini, A. [INFM, Dipartimento di Fisica, Genoa (Italy); Manfrinetti, P.; Palenzona, A. [INFM, Dipartimento di Chimica e Chimica Industriale, Genoa (Italy)

    2001-09-01

    As-grown superconducting MgB{sub 2} thin films were deposited by pulsed laser deposition on magnesium oxide and sapphire substrates. Starting from a non-stoichiometric, Mg and B mixed-powder target, we were able to grow the superconducting phase during the film deposition, without any further annealing process. So far, samples grown in the temperature range of 400-450 deg. C, and at an argon buffer pressure of the order of 10{sup -2} mbar turned out to be superconducting with an onset temperature of the resistive transition at about 25 K. Even if the deposition process still needs to be fully optimized, we have demonstrated that this method allows us to achieve in situ deposition of as-grown superconducting thin films. This procedure could therefore be promising for the deposition of high-quality epitaxial MgB{sub 2} thin films. (author)

  18. Hybrid inorganic–organic superlattice structures with atomic layer deposition/molecular layer deposition

    OpenAIRE

    Tynell, Tommi; Yamauchi, Hisao; Karppinen, Maarit

    2014-01-01

    A combination of the atomic layer deposition (ALD) and molecular layer deposition (MLD) techniques is successfully employed to fabricate thin films incorporating superlattice structures that consist of single layers of organic molecules between thicker layers of ZnO. Diethyl zinc and water are used as precursors for the deposition of ZnO by ALD, while three different organic precursors are investigated for the MLD part: hydroquinone, 4-aminophenol and 4,4′-oxydianiline. The successful superla...

  19. Evaluation of neodymium doped fluoride glass films deposited by pulsed laser deposition

    OpenAIRE

    Harwood, D.W.J.; Eason, R. W.; Taylor, E. R.

    1997-01-01

    Pulsed laser deposition (PLD) has been evaluated as a technique for the realisation of neodymium doped fluoride glass waveguides. In contrast to other high energy techniques such as sputtering and molecular beam epitaxy, pulsed laser deposition appears to reliably reproduce the bulk stoichiometry of the doped glass in thin film form. However, characteristically for this deposition technique, the film topography is dominated by micron size particulates generated during fabrication. Film unifor...

  20. The deposit operations of commercial banks of Ukraine, their organization and deposit policy

    OpenAIRE

    Bobyl, V. V.; Kornilenko, M. S.

    2015-01-01

    The purpose. The work is devoted to the nature of the Deposit activity of the Bank, to highlight the features of the Deposit policy of the Bank and ways of increase of efficiency of management of the Deposit operations of the Bank. The basic problems faced by banks in implementing their Deposit activity, in particular: lack of active-passive operations of banks, the lack of resources accumulated by banking institutions to ensure the financial needs of the economy. The main ways to improve Dep...

  1. Ultrafast deposition of silicon nitride and semiconductor silicon thin films by Hot Wire Chemical Vapor Deposition

    OpenAIRE

    Schropp, R.E.I.; van der Werf, C.H.M.; Verlaan, V.; J.K. Rath; Li, H. B. T.

    2009-01-01

    The technology of Hot Wire Chemical Vapor Deposition (HWCVD) or Catalytic Chemical Vapor Deposition (Cat-CVD) has made great progress during the last couple of years. This review discusses examples of significant progress. Specifically, silicon nitride deposition by HWCVD (HW-SiNx) is highlighted, as well as thin film silicon single junction and multijunction junction solar cells. The application of HW-SiNx at a deposition rate of 3 nm/s to polycrystalline Si wafer solar cells has led to cell...

  2. Electrophoretic deposition of titania nanoparticles: Wet density of deposits during EPD

    Indian Academy of Sciences (India)

    Morteza Farrokhi-Rad; Taghi Shahrabi; Shirin Khanmohammadi

    2014-08-01

    Electrophoretic deposition (EPD) of titania nanoparticles was performed at different voltages and times. The wet density of deposits was calculated according to the Archimedes’ principle. The wet density as well as the electric field over the deposits increased with time and attained the plateau at longer times. The velocity at which particles attach to the deposit, strongly influences its wet density at initial times. However, the effect of electro-osmotic flow is dominant at longer times. The coating with higher wet density had the higher corrosion resistance in Ringer’s solution at 37.5 °C due to its closely packed and crack free microstructure.

  3. Surface effects on the mechanical elongation of AuCu nanowires: De-alloying and the formation of mixed suspended atomic chains

    Energy Technology Data Exchange (ETDEWEB)

    Lagos, M. J. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, R. Sergio B. de Holanda 777, 13083-859 Campinas-SP (Brazil); Laboratório Nacional de Nanotecnologia-LNNANO, 13083-970 Campinas-SP (Brazil); Autreto, P. A. S.; Galvao, D. S., E-mail: galvao@ifi.unicamp.br; Ugarte, D. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, R. Sergio B. de Holanda 777, 13083-859 Campinas-SP (Brazil); Bettini, J. [Laboratório Nacional de Nanotecnologia-LNNANO, 13083-970 Campinas-SP (Brazil); Sato, F.; Dantas, S. O. [Departamento de Física, ICE, Universidade Federal de Juiz de Fora, 36036-330 Juiz de Fora-MG (Brazil)

    2015-03-07

    We report here an atomistic study of the mechanical deformation of Au{sub x}Cu{sub (1−x)} atomic-size wires (nanowires (NWs)) by means of high resolution transmission electron microscopy experiments. Molecular dynamics simulations were also carried out in order to obtain deeper insights on the dynamical properties of stretched NWs. The mechanical properties are significantly dependent on the chemical composition that evolves in time at the junction; some structures exhibit a remarkable de-alloying behavior. Also, our results represent the first experimental realization of mixed linear atomic chains (LACs) among transition and noble metals; in particular, surface energies induce chemical gradients on NW surfaces that can be exploited to control the relative LAC compositions (different number of gold and copper atoms). The implications of these results for nanocatalysis and spin transport of one-atom-thick metal wires are addressed.

  4. Surface effects on the mechanical elongation of AuCu nanowires: De-alloying and the formation of mixed suspended atomic chains

    International Nuclear Information System (INIS)

    We report here an atomistic study of the mechanical deformation of AuxCu(1−x) atomic-size wires (nanowires (NWs)) by means of high resolution transmission electron microscopy experiments. Molecular dynamics simulations were also carried out in order to obtain deeper insights on the dynamical properties of stretched NWs. The mechanical properties are significantly dependent on the chemical composition that evolves in time at the junction; some structures exhibit a remarkable de-alloying behavior. Also, our results represent the first experimental realization of mixed linear atomic chains (LACs) among transition and noble metals; in particular, surface energies induce chemical gradients on NW surfaces that can be exploited to control the relative LAC compositions (different number of gold and copper atoms). The implications of these results for nanocatalysis and spin transport of one-atom-thick metal wires are addressed

  5. Uranium deposits in magmatic and metamorphic rocks

    International Nuclear Information System (INIS)

    The association of uranium with certain types of magmatic and metamorphic rocks is well known. They have consequently been explored and studied quite extensively. In recent years interest in them has been eclipsed by the discovery of larger, lower cost deposits in other geological environments. Nonetheless, magmatic and metamorphic rocks continue to be important sources of uranium and large areas of the Earth's crust with such rocks are prospective locations for additional discoveries. As future exploration and development could be more difficult the full importance of individual deposits may not be recognized until after many years of investigation and experience. In addition to being important host rocks, magmatic and metamorphic rocks have been of considerable interest to uranium geologists as they are considered to be important source rocks for uranium and thus can lead to deposits nearby in other environments. Furthermore, these rocks provide important information on the geochemical cycle of uranium in the Earth's crust and mantle. Such information can lead to identification of uranium provinces and districts and to a basic understanding of processes of formation of uranium deposits. The International Atomic Energy Agency convened a Technical Committee Meeting on Uranium Deposits in Magmatic and Metamorphic Rocks. The meeting was held in Salamanca, Spain, from 29 September to 3 October 1986. It was followed by a two day field trip to uranium deposits in the Ciudad Rodrigo and Don Benito areas. The meeting was attended by 48 participants from 22 countries. Two panels were organized for discussion of the following topics: (1) ore deposit genesis and characterization and (2) exploration and resource assessment. The technical papers together with the panel reports form this publication. The scope and variety of the papers included and the panel reports provide a good coverage of current knowledge and thinking on uranium in magmatic and metamorphic rocks

  6. Dispersion, deposition and resuspension of atmospheric contaminants

    International Nuclear Information System (INIS)

    The following topics are discussed: dry deposition, oil shale fugitive air emissions, particle resuspension and translocation, theoretical studies and applications, and processing of emissions by clouds and precipitation. The concentration of contaminant species in air is governed by the rate of input from sources, the rate of dilution or dispersion as a result of air turbulence, and the rate of removal to the surface by wet and dry deposition processes. Once on the surface, contaminants also may be resuspended, depending on meteorological and surface conditions. An understanding of these processes is necessary for accurate prediction of exposures of hazardous or harmful contaminants to humans, animals, and crops. In the field, plume dispersion and plume depletion by dry deposition were studied by the use of tracers. Dry deposition was investigated for particles of both respiration and inhalation interest. Complementary dry deposition studies of particles to rock canopies were conducted under controlled conditions in a wind tunnel. Because of increasing concern about hazardous, organic gases in the atmosphere some limited investigations of the dry deposition of nitrobenzene to a lichen mat were conducted in a stirred chamber. Resuspension was also studied using tracers and contaminated surfaces and in the wind tunnel. The objective of the resuspension studies was to develop and verify models for predicting the airborne concentrations of contaminants over areas with surface contamination, develop resuspension rate predictors for downwind transport, and develop predictors for resuspension input to the food chain. These models will be of particular relevance to the evaluation of deposition and resuspension of both radionuclides and chemical contaminants

  7. Chemical characteristics of some major uranium deposits in western USA

    International Nuclear Information System (INIS)

    Multi-element chemical analyses of several thousand samples were retrieved from the US Geological Survey's computerized Rock Analysis Storage System and used to estimate the average abundances of various elements in each of several types of uranium deposits, in altered rocks associated with some of these deposits, and in unmineralized parts of the various host rocks. Deposits for which results are presented include the tabular deposits in the Morrison Formation, Ambrosia Lake district, New Mexico; secondary deposits in the Ambrosia Lake district; tabular deposits in the Morrison Formation of the Henry Mountains, Utah; tabular deposits in the Chinle Formation in Utah and Colorado; roll-type deposits in Tertiary rocks from the Texas Gulf district; roll-type deposits in the Tertiary basins of Wyoming; tabular deposits in the Entrada Sandstone in Colorado; and a vein-type deposit in crystalline rocks of the Front Range of Colorado. Statistical treatment of the data identified elements that were notably more or less abundant in the deposits and altered rocks than in the unmineralized parts of the host rocks. Comparisons of the mean abundances of elements in the deposits show that the chemical composition of roll-type deposits varies greatly even among deposits in the same district. By contrast, the chemical characteristics of tabular deposits display little variation; the Ambrosia Lake tabular deposits and those of the Henry Mountains district are particularly similar. The data place some constraints on the geochemical aspects of genetic models and suggest certain elements as potential prospecting guides

  8. Rocky Mountain Carbonate Spring Deposit development

    Science.gov (United States)

    Rainey, Dustin Kyle

    Relict Holocene carbonate spring deposits containing diverse biotic and abiotic depositional textures are present at Fall Creek cold sulphur springs, Alberta, Fairmont Hot Springs, British Columbia, and Hot Creek cold springs, British Columbia. The relict deposits are formed mainly of low-magnesium crystalline calcite contained in laterally continuous strata. Paleo-flow regimes were characterized by extensive sheet flow that increased the surface area of spring water exposed to the atmosphere. Calcite precipitated inorganically from spring water that attained CaCO3 supersaturation through agitation-induced CO2 degassing that was facilitated by elevated flow rates and a large surface area as spring water flowed down-slope. Thus, the deposits contain only minor amounts of detrital, mechanically deposited, and biogenic carbonate. Evaporation was only a minor contributor to CaCO3 supersaturation, mainly in quiescent environments. Photosynthetic CO2 removal did not measurably contribute to CaCO3 supersaturation. Calcite crystals precipitated in biotic facies formed from low to moderately supersaturated spring water, whereas abiotic dendrite crystals formed rapidly from highly supersaturated spring water. Calcite passively nucleated on cyanobacteria, bryophytes and macrophytes, and was probably facilitated by cyanobacterial extracellular polymeric substances. Cyanobacterial filaments and stromatolites are integral parts of all three deposits, whereas bryophytes were restricted to the Fall Creek and Hot Creek deposits. Diagenetic microbial degradation of crystalline calcite was common to all three deposits, but recrystallization was limited to the Fall Creek deposit. The amount and location of calcite precipitation relative to the vents was controlled by the concentrations of Ca2+ and HCO3- in solution, and discharge volume fluctuations. Spring water with high [Ca2+] and [HCO 3-] precipitated large amounts of calcite proximal to the vents (e.g. Fairmont), whereas spring

  9. Global Tsunami Deposits Database, a demonstration

    Science.gov (United States)

    Brocko, V. R.; Dunbar, P. K.

    2008-12-01

    A result of collaboration between NOAA's National Geophysical Data Center (NGDC) and the Cooperative Institute for Research in the Environmental Sciences (CIRES), the Global Tsunami Database includes instrumental records, human observations, and now, information inferred from the geologic record. Historical reports, tide gauge data, Deep Ocean Assessment and Reporting of Tsunamis (DART) data, and information gleaned from published tsunami deposit research build a multi-faceted view of tsunami hazards and their history around the world. Tsunami history provides clues to what might happen in the future, including frequency of occurrence and maximum wave heights. However, instrumental and written records commonly span too little time to reveal the full range of a region's tsunami hazard. The sedimentary deposits of tsunamis, identified with the aid of modern analogs, increasingly complement instrumental and human observations. By adding the component of tsunamis inferred from the geologic record, the database extends the record of tsunamis backward in time. Deposit locations, their estimated age and descriptions of the deposits themselves fill in the tsunami record. Tsunamis inferred from proxies, such as evidence for coseismic subsidence, are included to estimate recurrence intervals, but are flagged to highlight the absence of a physical deposit. NGDC and CIRES welcome contributions and suggestions to improve the content and presentation of the database. Authors may submit their own descriptions and upload digital versions of publications. The data and information may be searched and viewed using tools designed to extract and display data from the Oracle database (selection forms, Web Map Services, and Web Feature Services). For example, users may select or sort by many fields, including event, location, region, age of deposit, author, publication type, grain size, composition, presence/absence of plant material. They may find tsunami deposit references for a given

  10. Stable isotope (S, O, H and C) studies of the phyllic and potassic phyllic alteration zones of the porphyry copper deposit at Sungun, East Azarbaidjan, Iran

    Science.gov (United States)

    Calagari, Ali Asghar

    2003-05-01

    The porphyry copper deposit (PCD) at Sungun is located in East Azarbaidjan, NW of Iran. The magmatic suites in the Sungun area are a part of the NW-SE trending Cenozoic magmatic belt of Iran. The Sungun porphyries occur as stocks and dikes. The stocks are divided into two groups, I and II. Porphyry Stock II, ranging in composition from quartz monzonite through granodiorite to granite, hosts the Sungun PCD. Four distinct types of hypogene alterations were recognized at Sungun: (1) potassic; (2) potassic-phyllic; (3) phyllic; and (4) propylitic. Stable isotope (S, O, H, and C) studies were restricted to within the phyllic and potassic-phyllic alteration zones, where numerous cross-cutting quartz, sulfides, carbonates, and sulfate veinlets are present. The objective of these studies was to determine the origin of the ore-forming solutions, and their important components (e.g. sulfur and carbon). Twenty sulfide and four sulfate samples were taken from sulfide and gypsum veinlets within Porphyry Stock II and the associated skarn zone for sulfur isotopic analyses. The δ34S values of sulfides (pyrite, chalcopyrite, molybdenite, galena, sphalerite) and sulfate (gypsum) range from -4.6 to -0.2‰ (mean of -1.5‰) and from 10.9 to 14.4‰ (mean of 12.9‰), respectively. These values are almost analogous to those from El Salvador (Chile) and Ajo (Arizona), and Twin Buttes (Arizona), and strongly suggest a magmatic source for the sulfur at Sungun. Twenty-eight fluid inclusion-rich quartz samples from quartz veinlets beneath the supergene zones of the Porphyry Stock II were chosen for O and H isotopic analyses. The δ18O (of quartz) and δD (of fluid inclusions in quartz) values range from 8.3 to 10.2‰ (mean of 9.2‰) and -58 to -75‰ (mean of -66‰) relative to Standard Mean Ocean Water (SMOW), respectively. The calculated δ18O values of the fluids range from 4.4‰ (T=375 ° C) to 7.6‰ (T=570 ° C) with a mean of 6.4‰. The δ18O and δD values of the fluids lie

  11. Pulsed laser deposition of pepsin thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kecskemeti, G. [Department of Optics and Quantum Electronics, University of Szeged, H-6720 Szeged, Dom ter 9 (Hungary)]. E-mail: kega@physx.u-szeged.hu; Kresz, N. [Department of Optics and Quantum Electronics, University of Szeged, H-6720 Szeged, Dom ter 9 (Hungary); Smausz, T. [Hungarian Academy of Sciences and University of Szeged, Research Group on Laser Physics, H-6720 Szeged, Dom ter 9 (Hungary); Hopp, B. [Hungarian Academy of Sciences and University of Szeged, Research Group on Laser Physics, H-6720 Szeged, Dom ter 9 (Hungary); Nogradi, A. [Department of Ophthalmology, University of Szeged, H-6720, Szeged, Koranyi fasor 10-11 (Hungary)

    2005-07-15

    Pulsed laser deposition (PLD) of organic and biological thin films has been extensively studied due to its importance in medical applications among others. Our investigations and results on PLD of a digestion catalyzing enzyme, pepsin, are presented. Targets pressed from pepsin powder were ablated with pulses of an ArF excimer laser ({lambda} = 193 nm, FWHM = 30 ns), the applied fluence was varied between 0.24 and 5.1 J/cm{sup 2}. The pressure in the PLD chamber was 2.7 x 10{sup -3} Pa. The thin layers were deposited onto glass and KBr substrates. Our IR spectroscopic measurements proved that the chemical composition of deposited thin films is similar to that of the target material deposited at 0.5 and 1.3 J/cm{sup 2}. The protein digesting capacity of the transferred pepsin was tested by adapting a modified 'protein cube' method. Dissolution of the ovalbumin sections proved that the deposited layers consisted of catalytically active pepsin.

  12. Pharmacological approach to evaluate aerosol pulmonary deposition.

    Science.gov (United States)

    Girodet, Pierre-Olivier; Molimard, Mathieu

    2005-01-01

    Drug delivery to the lung in vivo may be assessed using pharmacokinetic or pharmacodynamic techniques. The choice of method depends on drug class specificities. Pharmacokinetic determination of deposition to the lung for drugs without hepatic first-pass effect, such as short acting beta2-agonists, has to be done shortly after inhalation to minimize the effect of gastrointestinal absorption. For medication undergoing important hepatic first-pass metabolisation, such as inhaled corticosteroid, plasma concentration indirectly reflects bronchial deposition. The pharmacodynamic profile should be assessed through clinical effects and adverse events induced by inhaled drugs. Dose ranking of lung deposition for bronchodilators requires patient selection with sufficient bronchial obstruction to maintain room for improvement after the first dose. To assess dose effect relationship between inhaled corticosteroid, the Finney parallel line bioassay is the reference method with a study period of at least 6 weeks. Analysis of side effects with high doses of beta2-agonists or inhaled corticosteroids may also be used to compare lung deposition. Finally, pharmacological evaluation of lung deposition provides complementary information to scintigraphic studies, based on their clinical relevance. PMID:15966772

  13. Definition and classification of surficial uranium deposits

    International Nuclear Information System (INIS)

    Uraniferous surficial deposits may be broadly defined as uraniferous sediments or soils, usually of Tertiary to Recent age, that have not been subjected to deep burial and may or may not have been cemented to some degree. Evaluation of the available literature shows that confusion has arisen as to the use of the term ''calcrete'' when describing fluviatile sediments that have been calcified to a greater or lesser degree. It is felt that a useful purpose would be served by proposing a classification system which may go some way towards a redefinition of the applicable terminology. Unfortunately the terms ''calcrete'' or ''valley calcrete'' have been used to define Tertiary to Recent sediments ranging from boulder beds to silts which, in some Namibian examples, contain between 5 and 50% CaCO3 and as much as 90% total carbonate in some Australian surficial uranium deposits. It is proposed that the detrital material constituting the sediments be prefixed with the terms calcareous, dolomitic, gypsiferous, halitiferous or ferruginous (e.g. calcareous grit) rather than the terms calcrete, dolocrete, gypcrete, and ferricrete, all of which have genetic connotations. The latter group of terms are preferably used for the pedogenic uranium deposits only. This will have the effect of placing these deposits in categories of their own and not confusing the issue with the overprint of pedogenic calcrete or duricrustal deposits which may or may not be present. This view is not shared by some authorities notably Butt and Carlisle (see this volume). (author)

  14. Percolation and structural properties of particle deposits

    International Nuclear Information System (INIS)

    We investigate the percolation properties of configurations of spherical particles deposited by a generalized ballistic deposition model. In this model, a tuning parameter a is introduced for controlling the relative efficiency of two mechanisms: direct deposition and deposition by following the path of steepest descent on previously deposited particles. Any particle that is trapped in an elevated position after rolling is rejected. Exact critical exponents are obtained for the (1+1)-dimensional version of the model. We performed computer simulations of the (2+1)-dimensional version and by studying the percolative behavior both for fixed values of a, as a function of the surface coverage θ, and along the saturation curve θ(a,∞), we construct the percolation phase diagram of the model. Below a threshold value, ac congruent 3.05, there is no percolation transition, but we give some evidence for a ''virtual percolation line.'' The critical exponents β,γ,ν are determined by finite-size scaling and Monte Carlo renormalization group techniques, and are shown to be consistent with those of ordinary two-dimensional lattice percolation. Finally, changes of structure with a are illustrated through the pair distribution function and the pair connectedness function

  15. Dry deposition to vegetated surfaces: parametric dependencies

    International Nuclear Information System (INIS)

    The dry deposition velocity of airborne pollutants to vegetated surfaces depends on the physico-chemical form of the pollutant, on meteorological conditions (windspeed, atmospheric stability) and on characteristics of the surface cover. This report examines these dependencies, drawing on experimental data and on information from theoretical analyses. A canopy model is outlined which uses first-order closure of the equations for turbulent transport of momentum (or matter), with losses of momentum (or matter) to individual canopy elements parameterised in terms of the mean windspeed: the model has previously been tested against experimental data on an artificial 'grass' canopy. The model is used to elucidate the features of the dependence of deposition velocity on windspeed and on whether the pollutant is in gaseous or particulate form: in the former case, the dependence on the molecular diffusivity of the gas is shown; in the latter case, dependencies on particle diameter and density are deduced. The predictions are related to available measurements. Additional hypotheses are introduced to treat the influence of atmospheric stability on deposition, and the analysis is used to shed light on the somewhat confusing picture that has emerged from past experimental studies. In considering the dependence of deposition velocity on the structural properties of the vegetation, it is established that more parameters than the single one conventionally used -aerodynamic roughness length - are needed to characterise the surface cover. Some indications of the extent of variation in deposition velocity from one type of vegetation to another are elicited from the model. (author)

  16. Palladium clusters deposited on the heterogeneous substrates

    Science.gov (United States)

    Wang, Kun; Liu, Juanfang; Chen, Qinghua

    2016-07-01

    To improve the performance of the Pd composite membrane prepared by the cold spraying technology, it is extremely essential to give insights into the deposition process of the cluster and the heterogeneous deposition of the big Pd cluster at the different incident velocities on the atomic level. The deposition behavior, morphologies, energetic and interfacial configuration were examined by the molecular dynamic simulation and characterized by the cluster flattening ratio, the substrate maximum local temperature, the atom-embedded layer number and the surface-alloy formation. According to the morphology evolution, three deposition stages and the corresponding structural and energy evolution were clearly identified. The cluster deformation and penetrating depth increased with the enhancement of the incident velocity, but the increase degree also depended on the substrate hardness. The interfacial interaction between the cluster and the substrate can be improved by the higher substrate local temperature. Furthermore, it is found that the surface alloys were formed by exchanging sites between the cluster and substrate atoms, and the cluster atoms rearranged following as the substrate lattice arrangement from bottom to up in the deposition course. The ability and scope of the structural reconstruction are largely determined by both the size and incident energy of the impacted cluster.

  17. Model boiler studies on deposition and corrosion

    International Nuclear Information System (INIS)

    Deposit formation was studied in a model boiler, with sea-water injections to simulate the in-leakage which could occur from sea-water cooled condensers. When All Volatile Treatment (AVT) was used for chemistry control the deposits consisted of the sea-water salts and corrosion products. With sodium phosphate added to the boiler water, the deposits also contained the phosphates derived from the sea-water salts. The deposits were formed in layers of differing compositions. There was no significant corrosion of the Fe-Ni-Cr alloy boiler tube under deposits, either on the open area of the tube or in crevices. However, carbon steel that formed a crevice around the tube was corroded severely when the boiler water did not contain phosphate. The observed corrosion of carbon steel was caused by the presence of acidic, highly concentrated chloride solution produced from the sea-water within the crevice. Results of theoretical calculations of the composition of the concentrated solution are presented. (author)

  18. THE WATERSHED DEPOSITION TOOL: A MEANS TO LINK ATMOSPHERIC DEPOSITION TO WATERSHEDS

    Science.gov (United States)

    The potential for atmospheric deposition reductions to contribute to water quality management is not being included in many planning exercises. This is because often the water quality scientists do not know where to get and how to use projections of atmospheric deposition reducti...

  19. Controllable deposition of gadolinium doped ceria electrolyte films by magnetic-field-assisted electrostatic spray deposition

    International Nuclear Information System (INIS)

    This paper describes a simple and low-temperature approach to fabrication of dense and crack-free gadolinium doped ceria (GDC) thin films with controllable deposition by a magnetic-field-assisted electrostatic spray deposition technique. The influences of external permanent magnets on the deposition of GDC films were investigated. The coating area deposited using two magnets with the same pole arrangement decreased in comparison with the case of no magnets, whereas the largest deposition area was obtained in the system of the opposite poles. Analysis of as-deposited films at 450 °C indicated the formation of uniform, smooth and dense thin films with a single-phase fluorite structure. The films produced in the system using same poles were thicker, smaller in crystallite size and smoother than those fabricated under other conditions. Additionally, the GDC film deposited using the same pole arrangement showed the maximum in electrical conductivity of about 2.5 × 10−2 S/cm at a low operating temperature of 500 °C. - Highlights: • Magnetic-field-assisted electrostatic spray allows a controllable coating. • Dense, crack-free thin films were obtained at low process temperature of 450 °C. • Control of deposition, thickness and uniformity is easy to achieve simultaneously. • Films from the same pole were thicker, smaller in crystal size and smoother. • The maximum conductivity of doped ceria film was 2.5 × 10−2 S/cm at 500 °C

  20. The uranium ore deposits in Ciudad Rodrigo Phyllites. about the possibility of new deposits

    International Nuclear Information System (INIS)

    The main features of the genesis of uranium deposits of the Fe mine type, are discussed in this paper. Pitchblende ore is related with phyllites bearing organic material and with geomorphological level, fossilized by eocene sediments. As a result, new uranium ore deposits are possible under Ciudad Rodrigo tertiary basin, tertiary cover depth being little more than three hundred feet. (Author)

  1. Alternate slicing and deposition strategies for fused deposition modelling of light curved parts

    Directory of Open Access Journals (Sweden)

    B. Huang

    2012-12-01

    Full Text Available Fused deposition modeling (FDM, as one of the additive manufacturing (AM techniques, has been widely used in the manufacturing industry from the 1990s. It is relatively cheaper than other AM methods and there are other advantages such as being able to process a variety of other polymers. Currently, FDM is more likely to be suitable for direct production of the terminal-use parts, in some cases challenging traditional process such as injection molding. Research evidences indicate that change of road and layer structure would have significant influence on the meso-structure and thus impact the mechanical properties of the resulting polymer parts. Adaptive flat layer deposition and curved layer deposition have been introduced to improve the mechanical properties of terminal-use product. It is necessary that an appropriate deposition scheme is essential to ensure the best interroad and inter-layer connectivity. Uninterrupted connections are likely to result in a continuous network of polymer chains, as in the case of the conventional processes. The current research proposes conventional flat layer deposition, adaptive flat layer deposition and curved layer deposition for FDM. In particular for curved parts, curved layer deposition in expected to ensure fiber continuity and better meso-structure. Mathematical models are developed for curved slicing, practically implemented to print physical parts and test results suggest marked improvement in the mechanical characteristics of curved parts.

  2. Spatial atomic layer deposition: a route towards further industrialization of atomic layer deposition

    NARCIS (Netherlands)

    Poodt, P.W.G.; Cameron, D.C.; Dickey, E.; George, S.M.; Kuznetsov, V.; Parsons, G.N.; Roozeboom, F.; Sundaram, G.; Vermeer, A.

    2012-01-01

    Atomic layer deposition (ALD) is a technique capable of producing ultrathin conformal films with atomic level control over thickness. A major drawback of ALD is its low deposition rate, making ALD less attractive for applications that require high throughput processing. An approach to overcome this

  3. Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping

    Directory of Open Access Journals (Sweden)

    H. Guan

    2010-05-01

    Full Text Available Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the method. A high-resolution bulk chloride deposition map in the coastal region is thus needed. The aim of this study is to construct a chloride deposition map in the Mount Lofty Ranges (MLR, a coastal hilly area of approximately 9000 km2 spatial extent in South Australia. We examined geographic (related to coastal distance, orographic, and atmospheric factors that may influence chloride deposition, using partial correlation and regression analyses. The results indicate that coastal distance, elevation, as well as terrain aspect and slope, appear to be significant factors controlling chloride deposition in the study area. Coastal distance accounts for 70% of spatial variability in bulk chloride deposition, with elevation, terrain aspect and slope an additional 15%. The results are incorporated into a de-trended residual kriging model (ASOADeK to produce a 1 km×1 km resolution bulk chloride deposition and concentration maps. The average uncertainty of the deposition map is about 20–30% in the western MLR, and 40–50% in the eastern MLR. The maps will form a useful basis for examining catchment chloride balance for the CMB application in the study area.

  4. Deposition of Thin Film Electrolyte by Pulsed Laser Deposition (PLD) for micro-SOFC Development

    OpenAIRE

    Krogstad, Hedda Nordby

    2012-01-01

    Optimalization of PLD deposition of YSZ for micr-SOFC electrolyte applications by varying deposition pressure and target-substrate distance.Substrate used was Si-based chips and wafers (large area PLD), and the substrate temperature was held at 600. Dense films were obtained at 20 mTorr.

  5. Ash Deposition Trials at Three Power Stations in Denmark

    DEFF Research Database (Denmark)

    Laursen, Karin; Frandsen, Flemming; Larsen, Ole Hede

    1998-01-01

    the probe temperature did influence the composition of deposits for coals with medium ash deposition propensities. These results may indicate that coals with medium to high ash deposition propensities in existing boilers may cause increasing ash deposit formation in future boilers with higher steam...

  6. The Principles of Efficient Banking Deposit Insurance System ABSTRACT

    OpenAIRE

    Petr Dvořák

    2008-01-01

    The subject of article consists in banking deposit insurance system and in international experiences set the principles of efficient banking deposit insurance system for modern banking systems in global financial market. The recommended design of deposit insurance system is explicit insurance with broad client’s protection, which is comparable with systems in other countries where clients can easy transfer their deposit.

  7. 7 CFR 27.92 - Method of payment; advance deposit.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Method of payment; advance deposit. 27.92 Section 27... Micronaire § 27.92 Method of payment; advance deposit. Any payment or advance deposit under this subpart...,” and may not be made in cash except in cases where the total payment or deposit does not exceed...

  8. Influence of deposition time on the properties of chemical bath deposited manganese sulfide thin films

    Directory of Open Access Journals (Sweden)

    Anuar Kassim

    2010-12-01

    Full Text Available Manganese sulfide thin films were chemically deposited from an aqueous solution containing manganese sulfate, sodium thiosulfate and sodium tartrate. The influence of deposition time (2, 3, 6 and 8 days on the properties of thin films was investigated. The structure and surface morphology of the thin films were studied by X-ray diffraction and atomic force microscopy, respectively. In addition, in order to investigate the optical properties of the thin films, the UV-visible spectrophotometry was used. The XRD results indicated that the deposited MnS2 thin films exhibited a polycrystalline cubic structure. The number of MnS2 peaks on the XRD patterns initially increased from three to six peaks and then decreased to five peaks, as the deposition time was increased from 2 to 8 days. From the AFM measurements, the film thickness and surface roughness were found to be dependent on the deposition time.

  9. Effect of deposition pressure and post deposition annealing on SmCo thin film properties

    International Nuclear Information System (INIS)

    In this article we report on the effect of the deposition pressure and the post deposition annealing conditions on the structural and magnetic properties of SmCo thin films deposited on Si(100) wafers employing Ta buffer and capping layers. The films were deposited by DC magnetron sputtering and annealed in vacuum at various temperatures. The films under investigation were isotropic with high remanence magnetization, maximum coercive field of 8 kOe and a squareness ratio of coercivity higher than 0.9. It was found that the Ar pressure during the deposition is a key factor in controlling the stoichiometry and the structural and magnetic properties of the SmCo films, while the effect of the annealing temperature is crucial in optimizing the magnetic properties of the films. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Uranium and thorium deposits of Northern Ontario

    International Nuclear Information System (INIS)

    This, the second edition of the uranium-thorium deposit inventory, describes briefly the deposits of uranium and/or thorium in northern Ontario, which for the purposes of this circular is defined as that part of Ontario lying north and west of the Grenville Front. The most significant of the deposits described are fossil placers lying at or near the base of the Middle Precambrian Huronian Supergroup. These include the producing and past-producing mines of the Elliot Lake - Agnew Lake area. Also included are the pitchblende veins spatially associated with Late Precambrian (Keweenawan) diabase dikes of the Theano Point - Montreal River area. Miscellaneous Early Precambrian pegmatite, pitchblende-coffinite-sulphide occurrences near the Middle-Early Precambrian unconformity fringing the Lake Superior basin, and disseminations in diabase, granitic rocks, alkalic complexes and breccias scattered throughout northern Ontario make up the rest of the occurrences

  11. Measurements of surface deposition from seeded flames

    International Nuclear Information System (INIS)

    In the work reported here, the authors used Raman scattering from a surface deposit to determine its composition and thickness. Surface deposits of B2O3 are obtained by doping a CH4/H2/air flame with BCl3. The dependence of deposit growth and loss rates on surface temperature and the water and boron seed level in the combustion gases are discussed. At temperatures more than 200 K below the dew point, the observed growth and loss rate are explained by a near-constant arrival rate of boron at the surface with an enhanced volatilization at lower temperatures due to the formation of H3BO3 and (HBO2)3

  12. Worldwide deposition of strontium-90 through 1990

    International Nuclear Information System (INIS)

    Strontium-90 results from the Environmental Measurements Laboratory's (EML) Global Fallout Program (GFP) are presented for the years 1987 through 1990. Quarterly 90Sr deposition results for the 66 sampling locations of EML's GFP were generally low, indicating that there was no significant release of fission products into the atmosphere during this period. The global 90Sr deposition during these 4 years was lower than it has been for any similar period since this program began in 1958. Since there was no major atmospheric source of 90Sr during this period, the global cumulative deposit of 90Sr continued to decrease by radioactive decay to a 27 year low of 311.4 Pbq

  13. Patterned deposition at moving contact lines

    CERN Document Server

    Thiele, Uwe

    2013-01-01

    When a simple or complex liquid recedes from a smooth solid substrate it often leaves a homogeneous or structured deposit behind. In the case of a receding non-volatile pure liquid the deposit might be a liquid film or an arrangement of droplets depending on the receding speed of the meniscus and the wetting properties of the system. For complex liquids with volatile components as, e.g., polymer solutions and particle or surfactant suspensions, the deposit might be a homogeneous or structured layer of solute - with structures ranging from line patterns that can be orthogonal or parallel to the receding contact line via hexagonal or square arrangements of drops to complicated hierarchical structures. We review a number of recent experiments and modelling approaches with a particular focus on mesoscopic hydrodynamic long-wave models. The conclusion highlights open question and speculates about future developments.

  14. Crud deposition modeling on BWR fuel rods

    International Nuclear Information System (INIS)

    Deposition of boiling water reactor (BWR) system corrosion products (crud) on operating fuel rods has resulted in performance-limiting conditions in a number of plants. The operational impact of performance-limiting conditions involving crud deposition can be detrimental to a BWR operator, resulting in unplanned or increased frequency of fuel inspections, fuel failure and associated radiological consequences, operational restrictions including core power derate and/or forced shutdowns to remove failed fuel, premature discharge of individual bundles or entire reloads, and/or undesirable core design restrictions. To facilitate improved management of crud-related fuel performance risks, EPRI has developed the CORAL (Crud DepOsition Risk Assessment ModeL) tool. This paper presents a summary of the CORAL elements and benchmarking results. Applications of CORAL as a tool for fuel performance risk assessment are also discussed. (author)

  15. Plant responses to insect egg deposition.

    Science.gov (United States)

    Hilker, Monika; Fatouros, Nina E

    2015-01-01

    Plants can respond to insect egg deposition and thus resist attack by herbivorous insects from the beginning of the attack, egg deposition. We review ecological effects of plant responses to insect eggs and differentiate between egg-induced plant defenses that directly harm the eggs and indirect defenses that involve egg parasitoids. Furthermore, we discuss the ability of plants to take insect eggs as warning signals; the eggs indicate future larval feeding damage and trigger plant changes that either directly impair larval performance or attract enemies of the larvae. We address the questions of how egg-associated cues elicit plant defenses, how the information that eggs have been laid is transmitted within a plant, and which molecular and chemical plant responses are induced by egg deposition. Finally, we highlight evolutionary aspects of the interactions between plants and insect eggs and ask how the herbivorous insect copes with egg-induced plant defenses and may avoid them by counteradaptations. PMID:25341089

  16. Model calculations to formation of salt deposits

    International Nuclear Information System (INIS)

    The present work is a contribution from the geophysical side and its target is to explain the formation of long stretched salt deposits - salt walls - in a better manner than has been done sofar using model calculations. A few works have already been dedicated to this subject (they are treated in chapter 5). They all have the disadvantage however in not being able to represent the time sequence of the salt deposit generations. Precisely the latter is achieved in this work by including assumed initial interference. The values for the salt wall distance and its growth rate are improved upon. The Schleswig-Holstein salt deposit is taken as example. The model calculations are supported by model experiments. (orig.)

  17. Washout and dry deposition of atmospheric aerosols

    International Nuclear Information System (INIS)

    The deposition velocities onto different rough surfaces and the washout coefficients of simulated rain droplets for submicron aerosols were studied in a wind channel. The influence of particle size and electric charge upon the collection efficiencies of simulated rain droplets was measured. The deposition velocity of the particles was determined as a function of aerosol size, wind velocity and roughness of the surface. The experiments were carried out with monodisperse, radioactive particles with sizes which were varied from 0.03 and 5 μm. Using the measured values, the activity flux of the long lived radon decay product (RaD), the mass flux of the atmospheric aerosol and the activity flux near a stack of a nuclear power plant onto the ground surface were calculated considering washout, rainout and dry deposition in the atmosphere. (author)

  18. Deposit control in process cooling water systems

    International Nuclear Information System (INIS)

    In order to achieve efficient heat transfer in cooling water systems, it is essential to control the fouling of heat exchanger surfaces. Solubilities of scale forming salts, their growth into crystals, and the nature of the surfaces play important roles in the deposition phenomenon. Condensed phosphates, organic polymers and compounds like phosphates are effective in controlling deposition of scale forming salts. The surface active agents inhibit crystal growth and modify the crystals of the scale forming salts, and thus prevent deposition of dense, uniformly structured crystalline mass on the heat transfer surface. Understanding the mechanism of biofouling is essential to control it by surface active agents. Certain measures taken in the plant, such as back flushing, to control scaling, sometimes may not be effective and can be detrimental to the system itself. (author)

  19. MOCVD deposition of YSZ on stainless steels

    Science.gov (United States)

    Chevalier, S.; Kilo, M.; Borchardt, G.; Larpin, J. P.

    2003-01-01

    Yttria stabilized zirconia was deposited on stainless steel using the metal-organic chemical vapor deposition (MOCVD) technique, from β-diketonate precursors. The variation of the evaporation temperatures of yttrium and zirconium precursor allowed to control the level of Y within the film. Over the temperature range 125-150 °C, the Y content increased from 2.5 to 17.6 at.%. X-ray diffraction (XRD) analyses evidenced tetragonal phase of zirconia when the Y content was below 8 at.%, and cubic phase for higher concentration. Sputtered neutral mass spectrometry (SNMS) profiles confirmed that the control and stability of Y precursor temperature were of major importance to guarantee the homogeneity of the deposited films.

  20. Multi-Constituent Simulation of Thrombus Deposition

    CERN Document Server

    Wu, Wei-Tao; Massoudi, Mehrdad; Wagner, William R; Antaki, James F

    2016-01-01

    Based on the transport model of Sorensen et al. (1999), an improved mathematical model describing the process of thrombus deposition and growth was developed. Blood is treated as a multi-constituent mixture comprised of a linear fluid phase and a thrombus phase. The transport and reactions of 10 chemical and biological species are modeled using a system of coupled convection-reaction-diffusion (CRD) equations. These represent three main processes: initiation, propagation and stabilization. Computational fluid dynamic (CFD) simulations using the libraries of OpenFOAM were performed for two illustrative benchmark problems: mural thrombus growth in an injured blood vessel and thrombus deposition in a small (125 x 95 micros) crevice observed in vitro. For both problems, the simulated thrombus deposition agreed very well with experimental observations, both spatially and temporally. These promising results encourage further simulations to investigate clinical conditions and design factors that affect the risk of t...

  1. Sputtering. [as deposition technique in mechanical engineering

    Science.gov (United States)

    Spalvins, T.

    1976-01-01

    This paper primarily reviews the potential of using the sputtering process as a deposition technique; however, the manufacturing and sputter etching aspects are also discussed. Since sputtering is not regulated by classical thermodynamics, new multicomponent materials can be developed in any possible chemical composition. The basic mechanism for dc and rf sputtering is described. Sputter-deposition is described in terms of the unique advantageous features it offers such as versatility, momentum transfer, stoichiometry, sputter-etching, target geometry (coating complex surfaces), precise controls, flexibility, ecology, and sputtering rates. Sputtered film characteristics, such as strong adherence and coherence and film morphology, are briefly evaluated in terms of varying the sputtering parameters. Also described are some of the specific industrial areas which are turning to sputter-deposition techniques.

  2. Simulation of Indoor Fine Suspension Particle Deposition

    Science.gov (United States)

    Li, K. Q.; Gong, G. C.; Zou, S. H.

    In this paper, the migration and deposition of particles are simulated using the Moment Dynamic Equation (MDE). Indoor fine suspension particle depositions and particle distribution function are obtained. Gas phase flow is simulated by v 2 - f model. The simulated results of particle concentration profiles show that a uniform concentration exists in the middle region of the room with a low supplying speed. At the same time, the total number of partciels deposited is also obtained using Gradient diffusion model. Through the comparison of velocity predictions among several CFD k-ɛ models and v 2 -f model and experimental data, it is concluded that the results obtained by v 2 -f model more accurately approximate the experimental data. So that the MDE combined v 2 -f model will gain in popularity amongst building engineers and it will gradually be adopted as an attractive alternative tool to predict contaminant particle dispersion and distribution.

  3. Atomic-layer deposition of silicon nitride

    CERN Document Server

    Yokoyama, S; Ooba, K

    1999-01-01

    Atomic-layer deposition (ALD) of silicon nitride has been investigated by means of plasma ALD in which a NH sub 3 plasma is used, catalytic ALD in which NH sub 3 is dissociated by thermal catalytic reaction on a W filament, and temperature-controlled ALD in which only a thermal reaction on the substrate is employed. The NH sub 3 and the silicon source gases (SiH sub 2 Cl sub 2 or SiCl sub 4) were alternately supplied. For all these methods, the film thickness per cycle was saturated at a certain value for a wide range of deposition conditions. In the catalytic ALD, the selective deposition of silicon nitride on hydrogen-terminated Si was achieved, but, it was limited to only a thin (2SiO (evaporative).

  4. Deposition of caesium to surfaces of buildings

    International Nuclear Information System (INIS)

    Outdoor surfaces of several different types of building material have been analysed for 134Cs and 137Cs and the results used to estimate deposition velocities using integrated air doses. The Chernobyl reactor accident would have been the only significant source of 134Cs and, for materials unlikely to have intercepted precipitation during the passage of the main plume, dry deposition velocities have been inferred. Substantial amounts of 137Cs on the older building materials would have been due to nuclear weapons fall-out. For brick walls, 134Cs levels were below the limits of analytical detection and upper limits of dry deposition velocity have been estimated. Values have also been inferred for roofing felt and flat clay and corrugated concrete roof tiles. 137Cs levels on older roofing materials indicate significant weathering of weapons fall-out. (author)

  5. Dry deposition of pan to grassland vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Doskey, P.V.; Wesely, M.L.; Cook, D.R.; Gao, W.

    1994-01-01

    Peroxyacetyl nitrate or PAN (CH{sub 3}C(O)OONO{sub 2}) is formed in the lower troposphere via photochemical reactions involving nitrogen oxides (NO{sub x}) and non-methane hydrocarbons (NMHCs). PAN has a lifetime in the free troposphere of about three months and is removed by photolysis or reaction with OH. Dry deposition will decrease its lifetime, although the few measurements that have been made indicate that this process is slow. Measurements of the uptake of PAN by alfalfa in growth chambers indicated that the dry deposition velocity (downward flux divided by concentration at a specified height) was 0.75 cm s{sup {minus}1}. Garland and Penkett measured a dry deposition velocity of 0.25 cm s{sup {minus}1} for PAN to grass and soil in a return-flow wind tunnel. Shepson et al. (1992) analyzed trends of PAN and O{sub 3} concentrations in the stable nocturnal boundary layer over mixed deciduous/coniferous forests at night, when leaf stomata were closed, and concluded that the deposition velocity for PAN was at least 0.5 cm s{sup {minus}1}. We measured the dry deposition velocity of PAN to a grassland site in the midwestern United States with a modified Bowen ratio technique. Experiments were conducted on selected days during September, October, and November of 1990. An energy balance Bowen ratio station was used to observe the differences in air temperature and water vapor content between heights of 3.0 and 0.92 m and to evaluate the surface energy balance. Air samples collected at the same two heights in Teflon {reg_sign} bags were analyzed for PAN by a gas chromatographic technique. We present an example of the variations of PAN concentrations and gradients observed during the day and compare measurements of the dry deposition velocity to expectations based on the physicochemical properties of PAN.

  6. Transport and Deposition of Electrosprayed Nanoparticles

    Science.gov (United States)

    Brown, Nicholas; Chiarot, Paul

    2015-11-01

    In an electrospray, high electric potentials are utilized to generate a fine aerosol of a conductive solvent. For this study, the solvent consisted of nanoparticles dispersed in alcohol. The nanoparticle suspensions act as printable nanoparticle inks. In this process, a glass capillary tube is held as a high electric potential relative to a grounded reference plate located below the tip. Droplets are ejected from the tube and are directed towards the ground plate. If the solvent is sufficiently volatile, it will rapidly evaporate while the droplets are in flight (due to the high surface area to volume ratio) leaving behind dry, highly charged nanoparticles. The droplets/nanoparticles are deposited onto a target substrate that is place onto the grounded plate. The transport of any individual droplet/nanoparticle from the emitter tip to the target substrate is a stochastic process. This transport can be modeled using a Monte Carlo simulation. The probability of an individual particle being deposited at a given location on the target substrate is directly related to the electric potential at that location. In other words, the probability function that determines the deposition is directly related to the electric potential at the substrate. The total potential is comprised of the applied electric potential required to generate the electrospray, the induced charge on the surface of the target dielectric, and the charge on the individual particles themselves. We report on the structure of droplet/nanoparticle deposits printed using electrospray. The evolution of the deposit is investigated over time using experimental studies and Monte Carlo simulations. The deposit structure passes through four distinct regimes that are characterized by repeatable bulk features.

  7. Texture of atomic layer deposited ruthenium

    OpenAIRE

    Musschoot, J.; Xie, Q; Deduytsche, D.; De Keyser, K; Longrie, D.; Haemers, J.; Van den Berghe, S.; Van Meirhaeghe, R. L.; D'Haen, Jan; Detavernier, C

    2010-01-01

    Ruthenium films were grown by plasma enhanced atomic layer deposition (ALD) on Si(1 0 0) and ALD TiN. X-ray diffraction (XRD) showed that the as-deposited films on Si(1 0 0) were polycrystalline, on TiN they were (0 0 2) oriented. After annealing at 800 degrees C for 60 s, all Ru films were strongly (0 0 2) textured and very smooth. Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) demonstrated that the lateral grain size of the annealed films was several 100 ...

  8. Solid Organic Deposition During Gas Injection Studies

    DEFF Research Database (Denmark)

    Dandekar, Abhijit Y.; Andersen, Simon Ivar; Stenby, Erling Halfdan

    also evident as oil fractions expelled from the top to bottom of the PVT cell were observed to vary in density, molecular weight, as well as darkness of color. The change in stability of the oil samples before and after the contact with gas was analyzed using flocculation threshold titration. The...... asphaltene content of the different oil samples were determined by the TP 143 method. The standard asphaltenes and the solid organic deposit recovered from the swelling tests were analyzed using FTIR, HPLC-SEC and H-1 NMR. The aim of these analyses is to reveal the molecular nature of the deposits formed...

  9. Diamond deposition on siliconized stainless steel

    International Nuclear Information System (INIS)

    Silicon diffusion layers in AISI 304 and AISI 316 type stainless steels were investigated as an alternative to surface barrier coatings for diamond film growth. Uniform 2 μm thick silicon rich interlayers were obtained by coating the surface of the steels with silicon and performing diffusion treatments at 800 deg. C. Adherent diamond films with low sp2 carbon content were deposited on the diffused silicon layers by a modified hot filament assisted chemical vapor deposition (HFCVD) method. Characterization of as-siliconized layers and diamond coatings was performed by energy dispersive X-ray analysis, scanning electron microscopy, X-ray diffraction and Raman spectroscopy.

  10. Polymer-assisted deposition of films

    Science.gov (United States)

    McCleskey,Thomas M.; Burrell,Anthony K.; Jia,Quanxi; Lin,Yuan

    2012-02-28

    A polymer assisted deposition process for deposition of metal nitride films and the like is presented. The process includes solutions of one or more metal precursor and soluble polymers having binding properties for the one or more metal precursor. After a coating operation, the resultant coating is heated at high temperatures under a suitable atmosphere to yield metal nitride films and the like. Such films can be conformal on a variety of substrates including non-planar substrates. In some instances, the films can be epitaxial in structure and can be of optical quality. The process can be organic solvent-free.

  11. Reactive sputter deposition of boron nitride

    International Nuclear Information System (INIS)

    The preparation of fully dense, boron targets for use in planar magnetron sources has lead to the synthesis of Boron Nitride (BN) films by reactive rf sputtering. The deposition parameters of gas pressure, flow and composition are varied along with substrate temperature and applied bias. The films are characterized for composition using Auger electron spectroscopy, for chemical bonding using Raman spectroscopy and for crystalline structure using transmission electron microscopy. The deposition conditions are established which lead to the growth of crystalline BN phases. In particular, the growth of an adherent cubic BN coating requires 400--500 C substrate heating and an applied -300 V dc bias

  12. Bioactive surfaces with atomic layer deposition

    OpenAIRE

    Kvalvik, Julie Nitsche

    2015-01-01

    The overall goal of this work has been to make bioactive surfaces with atomic layer deposition (ALD). To do this, a new ALD system with titanium tetraisopropoxide (TTIP) and lysine as precursors was developed with emphasis on studying the effects of pulsing times and deposition temperatures. TTIP was chosen as titanium is regarded to be biocompatible and lysine was chosen as poly-L-lysine is a part of the extra-cellular matrix (ECM) and hence affects cell adhesion. The effect of a water pulse...

  13. Treating paraffin deposits in producing oil wells

    Energy Technology Data Exchange (ETDEWEB)

    Noll, L.

    1992-01-01

    Paraffin deposition has been a problem for operators in many areas since the beginning of petroleum production from wells. An extensive literature search on paraffin problems and methods of control has been carried out, and contact was made with companies which provide chemicals to aid in the treatment of paraffin problems. A discussion of the nature of paraffins and the mechanisms of this deposition is presented. The methods of prevention and treatment of paraffin problems are summarized. Suggested procedures for handling paraffin problems are provided. Suggestions for areas of further research testing are given.

  14. Shanxi Finding Another Large Bauxite Deposit

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>According to Department of Resources of Shanxi,a new breakthrough has been made on the prospecting in the province.The preliminary result shows that another large bauxite mine has been found in Shiqie River in Baode County with a deposit height of 0.81- 8.01m and an estimate reserve of 140 million tons.Meanwhile 3 large-and 3 medium-size bauxite deposits have also been found in the northwest part of Shanxi including Hejiaqianhe of Xin County with an estimate reserve of 37.1 million tons and Beiguli of Jiaokou County.

  15. Risk Adjusted Deposit Insurance for Japanese Banks

    OpenAIRE

    Ryuzo Sato; Rama V. Ramachandran; Bohyong Kang

    1990-01-01

    The purpose of this paper is to evaluate the Japanese deposit insurance scheme by contrasting the flat insurance rate with a market-determined risk-adjusted rate. The model used to calculate the risk-adjusted rate is that of Ronn and Verrna (1986) . It utilizes the notion of Merton(1977) that the deposit insurance can be based on a one-to-one relation between it and the put option; this permits the application of Black and Scholes(1973) model for the calculation of the insurance rate. The ris...

  16. XRF analysis of depth profiled thin depositions

    International Nuclear Information System (INIS)

    The main information about atmospheric and water pollutants is obtained from analysis of thin depositions on filters. Due its high sensitivity for a large number of elements, the XRF analysis based on X-ray tube as source of excitation, is a very advantageous method to measure samples of this kind. However, due to very large absorption photon cross sections in this energy range, the deposition profile can play an important role in analysis. Neglecting it might lead in some cases to wrong results. Assuming a normalized exponentially decaying profile as a realistic approximation of the deposition profile of a given element as ρ(x) = mkme-kmx/(1- e-kmD), where ρ(x) is element density at depth x, m - its surface density, km - deposition parameter and D - sample thickness, the yield, Y(km), of a characteristic X-line measured on a side of the sample is given as a function of Φ(E) - incident X-ray flux at energy E, σf(E) - photoelectric absorption cross section of the element, χ(E) - total X-ray absorption coefficient in sample considering both incidence and emergence path. Measuring the sample on the opposite side, the yield will be Y(-km), while from the ratio Y(-km)/Y(km) can be determined numerically. Since y(km) = Y(km)/m is independent of m, the deposition superficial mass is calculated using a thick standard as m = Y(s)S(x)/y(km)S(s), where S(x) (S(s)) is the X-line intensity measured in sample (standard) and theoretical yield in standard Y(s) is calculated using the formulas of Shiraiwa and Fujino. A computer code based on this formalism was written. Many samples of wet soil and aerosols deposition on filters, previously measured by other methods, were used to check the correctness of the present analysis procedure and a very good agreement is found between our results and the measurements taken as reference. A table is given with the results of the IAEA soil standard SOIL-7, deposited wet on a thin filter and measured after drying. The soil deposition was 3

  17. Wax deposition in crude oil pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Assuncao, Pablo Morelato; Rodrigues, Lorennzo Marrochi Nolding [Universidade Federal do Espirito Santo, Sao Mateus, ES (Brazil). Centro Universitario Norte do Espirito Santo. Engenharia de Petroleo; Romero, Mao Ilich [University of Wyoming, Laramie, WY (United States). Enhanced Oil Recovery Institute], e-mail: mromerov@uwyo.edu

    2010-07-01

    Crude oil is a complex mixture of hydrocarbons which consists of aromatics, paraffins, naphthenics, resins asphaltenes, etc. When the temperature of crude oil is reduced, the heavy components, like paraffin, will precipitate and deposit on the pipe internal wall in the form of a wax-oil gel. The gel deposit consists of wax crystals that trap some amount of oil. As the temperature gets cooler, more wax will precipitate and the thickness of the wax gel will increase, causing gradual solidification of the crude and eventually the oil stop moving inside the offshore pipeline. Crude oil may not be able to be re-mobilized during re-startup. The effective diameter will be reduced with wax deposition, resulting in several problems, for example, higher pressure drop which means additional pumping energy costs, poor oil quality, use of chemical components like precipitation inhibitors or flowing facilitators, equipment failure, risk of leakage, clogging of the ducts and process equipment. Wax deposition problems can become so sever that the whole pipeline can be completely blocked. It would cost millions of dollars to remediate an offshore pipeline that is blocked by wax. Wax solubility decreases drastically with decreasing temperature. At low temperatures, as encountered in deep water production, is easy to wax precipitate. The highest temperature below which the paraffins begins to precipitate as wax crystals is defined as wax appearance temperature (WAT). Deposition process is a complex free surface problem involving thermodynamics, fluid dynamics, mass and heat transfer. In this work, a numerical analysis of wax deposition by molecular diffusion and shear dispersion mechanisms in crude oil pipeline is studied. Diffusion flux of wax toward the wall is estimated by Fick's law of diffusion, in similar way the shear dispersion; wax concentration gradient at the solid-liquid interface is obtained by the volume fraction conservation equation; and since the wax deposition

  18. Distribution And Mineralogy Of The Clay Deposits In Saudi Arabia

    OpenAIRE

    Al Mohandis, Ahmed A. [احمد عبد القادر المهندس

    1993-01-01

    The main goal of this paper is to characterize the mineral clay deposits in Saudi Arabia; especially their mineral composition, deposit size, geological setting and possible uses. Different published reports and papers on clay deposits of Saudi Arabia have been reviewed. Three major clay deposits have been studied by XRD, DTA and chemical analyses. Saudi clay deposits consist generally of kaolinite as a major mineral, and small amounts other clay minerals, such as montmorillonite and illite. ...

  19. Dual ion beam assisted deposition of biaxially textured template layers

    Energy Technology Data Exchange (ETDEWEB)

    Groves, James R.; Arendt, Paul N.; Hammond, Robert H.

    2005-05-31

    The present invention is directed towards a process and apparatus for epitaxial deposition of a material, e.g., a layer of MgO, onto a substrate such as a flexible metal substrate, using dual ion beams for the ion beam assisted deposition whereby thick layers can be deposited without degradation of the desired properties by the material. The ability to deposit thicker layers without loss of properties provides a significantly broader deposition window for the process.

  20. Deposit Insurance Without Commitment: Wall St. Versus Main St

    OpenAIRE

    2011-01-01

    This paper studies the provision of deposit insurance without commitment in an economy with heterogenous households. When households are identical, deposit insurance will be provided ex post to reap insurance gains. But the ex post provision of deposit insurance redistributes consumption when households differ in their claims on the banking system as well as in their tax obligations to finance the deposit insurance. Deposit insurance will not be provided ex post if it requires a (socially) un...

  1. 12 CFR 347.203 - Deposit insurance required for all branches of foreign banks engaged in domestic retail deposit...

    Science.gov (United States)

    2010-01-01

    ... foreign banks engaged in domestic retail deposit activity in the same State. 347.203 Section 347.203 Banks... engaged in domestic retail deposit activity in the same State. The FDIC will not insure deposits in any... foreign bank in the same state that engages in domestic retail deposit activity will be an insured branch....

  2. State-of-the-art Pb photocathodes deposited by pulsed laser deposition

    International Nuclear Information System (INIS)

    In this article we present and discuss the current status of thin film Pb photocathodes deposited by pulsed laser deposition (PLD) with different laser parameters, such as laser fluence, wavelength or pulse duration. The PLD technique appears very efficient for the fabrication of pure Pb photocathodes, providing good adherence and respectable quantum efficiency. The films deposited on the picosecond and subpicosecond regimes are practically free of big droplets and fragments, whereas in the nanosecond regime their presence cannot be neglected. All the films present a granular structure and polycrystalline character with preferential orientation along the (111) crystalline planes, irrespective of the laser pulse duration or wavelength. The main results obtained from the photoemission performance of Pb thin films deposited by PLD demonstrate their chemical stability under vacuum conditions and respectable quantum efficiency with a maximum of 7.3×10−5 for films deposited on the subpicosecond regime. The photoemission properties confirm that Pb thin films deposited by PLD are a notable alternative for the fabrication of photocathodes for superconductive radio-frequency electron guns. - Highlights: • Lead samples were grown by Pulsed Laser Deposition at different laser parameters • All films present a granular morphology • Lead films grow preferentially along the 111 crystalline planes of the cubic net • A maximum quantum efficiency of 7.3 × 10-5 has been found

  3. Atomic layer deposition of nanoporous biomaterials.

    Energy Technology Data Exchange (ETDEWEB)

    Narayan, R. J.; Adiga, S. P.; Pellin, M. J.; Curtiss, L. A.; Stafslien, S.; Chisholm, B.; Monteiro-Riviere, N. A.; Brigmon, R. L.; Elam, J. W.; Univ. of North Carolina; North Carolina State Univ.; Eastman Kodak Co.; North Dakota State Univ.; SRL

    2010-03-01

    Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials. Nanoporous alumina, also known as anodic aluminum oxide (AAO), is a nanomaterial that exhibits several unusual properties, including high pore densities, straight pores, small pore sizes, and uniform pore sizes. In 1953, Keller et al. showed that anodizing aluminum in acid electrolytes results in a thick layer of nearly cylindrical pores, which are arranged in a close-packed hexagonal cell structure. More recently, Matsuda & Fukuda demonstrated preparation of highly ordered platinum and gold nanohole arrays using a replication process. In this study, a negative structure of nanoporous alumina was initially fabricated and a positive structure of a nanoporous metal was subsequently fabricated. Over the past fifteen years, nanoporous alumina membranes have been used as templates for growth of a variety of nanostructured materials, including nanotubes, nanowires, nanorods, and nanoporous membranes.

  4. Kinetic modeling of BN deposition by PECVD

    International Nuclear Information System (INIS)

    We present kinetic modeling of BN deposition by PECVD in the system B-N-H-X where X represents the gases F, Cl, Br or O, respectively. In the first step the thermodynamic data as well as kinetic coefficients are collected from literature and compared with each others. The kinetic coefficients also include the most important plasma reactions. With data set up selected calculations were performed in the program ''CHEMKIN''. Kinetic modeling was executed with the perfectly stirred reactor model. This model requires modeling of volume reactions as well as reactions on the surface. The rate coefficients for the surface reactions are investigated through parameter studies. Results of these parameter studies are compared with data known from experiments to obtain the probably way of reaction mechanisms. Data from kinetic modeling are also compared with results from calculations in thermodynamic equilibrium. Results of kinetic and equilibrium modeling show that the range where BN can be deposited is very sensitive to the mole fraction of the species X which is used. Using oxygen as well as fluorine there exist only few parameter compositions to deposit BN. These parameter sets are very important in relation to possible etching effects in PECVD of c-BN deposition

  5. Deposition of grids on plastic detectors

    CERN Document Server

    Birabeau, J P; Mendola, Onofrio

    1972-01-01

    In order to facilitate the locating of tracks of charged particles in cellulose-nitrate and polycarbonate (Makrofol, Lexan) foils, a method has been developed for the photo-deposition of translucent coordinate grids on these materials. The grids are resistant to the strongly caustic solutions used in developing tracks in plastic foils. (9 refs) .

  6. Panel 1 - comparative evaluation of deposition technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R.; Stodolsky, F. [Argonne National Lab., IL (United States); Benson, D.K.; Pitts, R.J. [National Renewable Energy Lab., Golden, CO (United States); Bhat, D.G. [GTE Valenite Corp., Troy, MI (United States); Yulin Chen [Allison Gas Turbine Division, GM, Indianapolis, IN (United States); Gat, R.; Sunkara, M.K. [Case Western Reserve Univ., Cleveland, OH (United States); Kelly, M. [Stanford Univ., CA (United States); Lawler, J.E. [Univ. of Wisconsin, Madison (United States); Nagle, D.C. [Martin Marietta Labs., Baltimore, MD (United States); Outka, D. [Sandia National Laboratories, Livermore, CA (United States); Revankar, G.S. [Deere & Co., Moline, IL (United States); Subramaniam, V.V. [Ohio State Univ., Columbus (United States); Wilbur, P.J. [Colorado State Univ., Fort Collins (United States); Mingshow Wong [Northwestern Univ., Evanston, IL (United States); Woolam, W.E. [Southwest Research Inst., Arlington, VA (United States)

    1993-01-01

    This working group attempted to evaluate/compare the different types of deposition techniques currently under investigation for depositing diamond and diamond-like carbon films. A table lists the broad types of techniques that were considered for depositing diamond and diamond-like carbon films. After some discussion, it was agreed that any evaluation of the various techniques would be dependent on the end application. Thus the next action was to list the different areas where diamond and DLC films could find applications in transportation. These application areas are listed in a table. The table intentionally does not go into great detail on applications because that subject is dealt with specifically by Panel No. 4 - Applications To Transportation. The next action concentrated on identifying critical issues or limitations that need to be considered in evaluating the different processes. An attempt was then made to rank different broad categories of deposition techniques currently available or under development based on the four application areas and the limitations. These rankings/evaluations are given for diamond and DLC techniques. Finally, the working group tried to identify critical development and research issues that need to be incorporated into developing a long-term program that focuses on diamond/DLC coatings for transportation needs. 5 tabs.

  7. New Mexico Known Mineral Deposit Areas

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset contains all Known Mineral Deposit Areas in the state of New Mexico. It is in a vector digital structure digitized from a 1:500,000 scale map of the...

  8. Deposition Diagnostics for Next-step Devices

    Energy Technology Data Exchange (ETDEWEB)

    C.H. Skinner; A.L. Roquemore; the NSTX team; A. Bader; W.R. Wampler

    2004-06-15

    The scale-up of deposition in next-step devices such as ITER will pose new diagnostic challenges. Codeposition of hydrogen with carbon needs to be characterized and understood in the initial hydrogen phase in order to mitigate tritium retention and qualify carbon plasma facing components for DT operations. Plasma facing diagnostic mirrors will experience deposition that is expected to rapidly degrade their reflectivity, posing a new challenge to diagnostic design. Some eroded particles will collect as dust on interior surfaces and the quantity of dust will be strictly regulated for safety reasons - however diagnostics of in-vessel dust are lacking. We report results from two diagnostics that relate to these issues. Measurements of deposition on NSTX with 4 Hz time resolution have been made using a quartz microbalance in a configuration that mimics that of a typical diagnostic mirror. Often deposition was observed immediately following the discharge suggesting that diagnostic shutters should be closed as soon as possible after the time period of interest. Material loss was observed following a few discharges. A novel diagnostic to detect surface particles on remote surfaces was commissioned on NSTX.

  9. Deposition of biopolymer films on micromechanical sensors

    DEFF Research Database (Denmark)

    Keller, Stephan Sylvest; Gammelgaard, Lene; Jensen, Marie P.;

    2011-01-01

    The influence of various parameters on the spray-coating of thin films of poly(l-lactide) (PLLA) was investigated. The optimized processing conditions were used for deposition of the biodegradable polymer on arrays of SU-8 microcantilevers. The resonance frequency of the cantilevers before and af...

  10. 20 CFR 901.46 - Depositions.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Depositions. 901.46 Section 901.46 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES REGULATIONS GOVERNING THE PERFORMANCE OF ACTUARIAL SERVICES UNDER THE EMPLOYEE RETIREMENT INCOME SECURITY ACT OF 1974 Suspension or Termination of...

  11. A literature review on wet deposition

    International Nuclear Information System (INIS)

    The literature on wet deposition or precipitation scavenging have been reviewed with special reference to predicting the radiological consequences of accidental contamination. The work was part of the EEC Radiation Protection Programme and done under a subcontract with Association Euratom-C.E.A. No. SC-014-BIAF-423-DK(SD). (author)

  12. Deposition Diagnostics for Next-step Devices

    International Nuclear Information System (INIS)

    The scale-up of deposition in next-step devices such as ITER will pose new diagnostic challenges. Codeposition of hydrogen with carbon needs to be characterized and understood in the initial hydrogen phase in order to mitigate tritium retention and qualify carbon plasma facing components for DT operations. Plasma facing diagnostic mirrors will experience deposition that is expected to rapidly degrade their reflectivity, posing a new challenge to diagnostic design. Some eroded particles will collect as dust on interior surfaces and the quantity of dust will be strictly regulated for safety reasons - however diagnostics of in-vessel dust are lacking. We report results from two diagnostics that relate to these issues. Measurements of deposition on NSTX with 4 Hz time resolution have been made using a quartz microbalance in a configuration that mimics that of a typical diagnostic mirror. Often deposition was observed immediately following the discharge suggesting that diagnostic shutters should be closed as soon as possible after the time period of interest. Material loss was observed following a few discharges. A novel diagnostic to detect surface particles on remote surfaces was commissioned on NSTX

  13. 31 CFR 223.4 - Deposits.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Deposits. 223.4 Section 223.4 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE SURETY COMPANIES DOING BUSINESS WITH THE UNITED...

  14. Atmosfærisk deposition 2000

    DEFF Research Database (Denmark)

    Ellermann, T.; Hertel, O.; Hovmand, M. F.;

    Denne rapport sammenfatter de vigtigste konklusioner fra dette års rapportering af atmosfæredelen af NOVA 2003 og opsummerer ovedresultaterne vedrørende måling og beregning af koncentrationer af atmosfæriske kvælstof-, fosfor-, svovlforbindelser og tungmetaller samt deposition til danske hav- og...... den største kvælstofdeposition, som hidtil er blevet rapporteret og ca. 20% højere end rapporteret for 1999 (Ellermann et al. 2000). For begge år viser de nyeste beregninger en tydeligt højere deposition til de danske farvande end hidtil rapporteret. Opdatering af model Det er vigtigt at bemærke, at...... den samlede deposition til de danske farvande, og dels højere kvælstofkoncentrationer i nedbøren. Denne forklaring underbygges af målingerne, som viser en svag stigning i våddepositionen fra 1999 til 2000 på trods af, at nedbørsmængden er lidt mindre i 2000 end 1999. Deposition opdelt på de...

  15. Crystal modified deposition of hydrated metal oxide

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, E.A.; Herce, J.A.

    1976-12-14

    A treating liquid for depositing a coating of hydrated metal oxide on a remotely located material (such as a subterranean sand mass to be consolidated) is improved by a crystal modifier. The treating liquid consists of an aqueous alkaline solution of an amphoteric metal compound, a pH-reducing reactant, and a hydroxyorganic crystal modifier. (4 claims)

  16. Solid Organic Deposition During Gas Injection Studies

    DEFF Research Database (Denmark)

    Dandekar, Abhijit Y.; Andersen, Simon Ivar; Stenby, Erling Halfdan

    2000-01-01

    Recently a series of first contact miscibility (swelling) experiments have been performed on undersaturated light and heavy oils using LPG rich and methane rich injection gases, in which solid organic deposition was observed. A compositional gradient in the oils during the gas injection process w...

  17. Absolute determination of bremsstrahlung deposition (Hydra)

    International Nuclear Information System (INIS)

    A technique developed to measure electron energy deposition in metals has been applied to the determination of bremsstrahlung deposition. In this method a square-wave beam modulation is employed and the time-derivative of a calorimeter temperature is used to obtain the energy deposited. This paper presents the results of bremsstrahlung deposition measurements in gold and aluminum. Data are presented for dose to a material as a function of converter material, converter thickness, and angle of electron incidence for electron energies in the range from 0.2 to 1.0 MeV. In addition, measurements of dose as a function of calorimeter position as it was moved both laterally and axially with respect to the beam axis are reported. Utilizing the facility and technique developed to make these measurements, a thorough study of the bremsstrahlung measuring calorimeters used with the pulsed electron beam machine Hydra was accomplished. The goal of this study was to determine accurately the correction factor for the loading effect of the thermocouple wires. The loading correction factor was measured to be 1.72 with an uncertainty of +- 5 percent. This value should be used when determining true dose to gold with the standard Hydra calorimeters instead of the value of 1.5 obtained from data on Hydra, since there is a larger uncertainty in the latter value. (U.S.)

  18. Low temperature CVD deposition of silicon carbide

    International Nuclear Information System (INIS)

    The coating of graphite on silicon carbide from the gaseous phase in a hot-well, open flow reactor at 1150degC is described. This study constitutes the first part of an investigation of the process for the coating of nuclear fuel by chemical vapor deposition (CVD)

  19. CVD diamond deposition onto dental burs

    International Nuclear Information System (INIS)

    A hot-filament chemical vapor deposition (HFCVD) system has been modified to enable non-planar substrates, such as metallic wires and dental burs, to be uniformly coated with thin polycrystalline diamond films. Initially, diamond deposition was carried out on titanium and tantalum wires in order to test and optimize the system. High growth rates of the order of approx. 8 /hr were obtained when depositing diamond on titanium wires using the vertical filament arrangement. However, lower growth rates of the order of 4-5meu m/hr were obtained with diamond deposition on tantalum wires. To extend the work towards a practical biomedical application tungsten carbide dental burs were coated with diamond films. The as-grown films were found to be polycrystalline and uniform over the cutting tip. Finally, the costs relating to diamond CVD onto dental burs have been presented in this paper. The costs relating to coating different number of burs at a time and the effect of film thickness on costs have been included in this investigation. (author)

  20. Generalized ballistic deposition of small buoyant particles

    Science.gov (United States)

    Csúcs, G.; Ramsden, J. J.

    1998-07-01

    The adsorption kinetics of the protein bee venom phospholipase A2 to a smooth, planar metal oxide surface has been measured under controlled hydrodynamic conditions using optical waveguide lightmode spectroscopy (OWLS). Adsorption follows the generalized ballistic deposition (GBD) model, except at low bulk protein concentrations, where Langmuir kinetics are observed.