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Sample records for copper sulfides

  1. Formation of Copper Sulfide Artifacts During Electrolytic Dissolution of Steel

    NASA Astrophysics Data System (ADS)

    Tan, Jia; Pistorius, P. Chris

    2013-06-01

    Based on equilibrium considerations, copper sulfide is not expected to form in manganese-containing steel, yet previous workers reported finding copper sulfide in transmission electron microscope samples which had been prepared by electropolishing. It is proposed that copper sulfide can form during electrolytic dissolution because of the much greater stability of copper sulfide relative to manganese sulfide in contact with an electrolyte containing copper and manganese cations. This mechanism has been demonstrated with aluminum-killed steel samples.

  2. Upper critical field of copper molybdenum sulfide

    NASA Technical Reports Server (NTRS)

    Alterovitz, S. A.; Woollam, J. A.

    1978-01-01

    The upper critical field of sintered and sputtered copper molybdenum sulfide Cu(x)Mo6S8 was measured and found to exceed the Werthamer, Helfand, and Hohenberg (1966) value for a type II superconductor characterized by dirty limit, weak isotropic electron phonon coupling, and no paramagnetic limiting. It is suggested that the enhancement results from anisotropy or clean limit or both. Other ternary molybdenum sulfides appear to show similar anomalies.

  3. Reactively evaporated films of copper molybdenum sulfide

    NASA Technical Reports Server (NTRS)

    Chi, K. C.; Dillon, R. O.; Bunshah, R. F.; Alterovitz, S.; Woollam, J. A.

    1978-01-01

    Films of superconducting Chevrel-phase copper molybdenum sulfide CuxMo6S8 were deposited on sapphire substrates by reactive evaporation using H2S as the reacting gas. Two superconducting temperatures (10.0 K and 5.0 K) of the films were found, corresponding to two different phases with different copper concentrations. All films were superconducting above 4.2 K and contained Chevrel-phase compound as well as free molybdenum. The critical current was measured as a function of applied field. One sample was found to deviate from the scaling law found for co-evaporated or sputtered samples, which possibly indicates a different pinning mechanism or inhomogeneity of the sample.

  4. Copper sulfide solid-state electrolytic memory devices

    NASA Astrophysics Data System (ADS)

    You, Liang

    Copper sulfide thin films with electrical switching and memory effect were grown using a chemical vapor reaction apparatus. The formation of copper sulfide film undergoes a process which includes nucleation, growth of nucleation, coalescence into continuous film, and film thickening. The initial phase of the sulfide growth was reaction limited followed by a diffusion limited phase involving out-diffusion of copper. The thin film tends to nucleate and grow at energy favorable sites such as twinning boundary. Sulfidation of polycrystalline copper results in formation of voids at the interface between the copper and its sulfide. (111) copper has the highest sulfidation rate followed by (100) and (110) copper planes. Moreover, the sulfidation rate near the microfabricated plug edge was found to be faster than the rate at the center of the plug. A mechanism based on competing sulfidation sites due to the geometry difference between the plugs' center and their edge is presented to explain this phenomenon. We show for the first time that field-assisted solid-electrolyte copper sulfide thin film device can function as a switch by reversing the voltage polarity between copper and inert metal electrodes through a copper-sulfide layer in planar and vertical structures. The copper oxide at the top of copper sulfide greatly increased the turn-on voltage. The turn-on voltage depends linearly on the film thickness. Copper sulfide devices in micrometer dimension were microfabricated using IC compatible techniques and characterized showing the same switching effect. Electrode contact area effect on switching performance was investigated in term of turn-on voltage, turn-off voltage, on-state resistance and off-state resistance. Four-point resistance measurement unit, Hall Effect and transfer length measurement were also fabricated together with copper sulfide switching devices and they were studied in order to determine the CuxS carrier type, carrier concentration, film resistivity

  5. Superconducting properties of evaporated copper molybdenum sulfide films

    NASA Technical Reports Server (NTRS)

    Woollam, J. A.; Chi, K. C.; Dillon, R. O.; Bunshah, R. F.; Alterovitz, S. A.

    1978-01-01

    Films of copper molybdenum sulfide were produced by coevaporation. Those that were superconducting contained only the ternary compound and free molybdenum. The range of copper content in the ternary compound was as large as that in polycrystalline material, that is, it includes either phase alone, or a mixture of the two phases of this material. This is in contrast with sputtered materials where copper concentration has been limited to a narrower range. The upper critical field and the critical current were measured as functions of external magnetic field, and found to be similar to those of sputtered copper molybdenum sulfide, when the comparison was made for samples having the same amount of copper.

  6. The cuprex metal extraction process: Recovering copper from sulfide ores

    NASA Astrophysics Data System (ADS)

    Dalton, R. F.; Diaz, G.; Price, R.; Zunkel, A. D.

    1991-08-01

    The Cuprex™ metal extraction process produces cathode-grade copper using a hydrometallurgical process based on chloride leaching of sulfide ore concentrates. The process incorporates several novel steps to overcome the major problems associated with earlier chloride-based processes, including mild leaching conditions using ferric chloride as leachant and solvent extraction of copper usinga novel reagent. This produces a highly concentrated cupric chloride electrolyte from which cathode-grade copper is electrowon in the Metclor cell. The technical viability and robustness of the core technology have been proven in a series of large-scale pilot trials. More recent work has concentrated on supplementary processes to convert the copper powder product to an article of commerce and to recover valuable by-products. A fully integrated scheme is now being developed with updated cost estimates.

  7. Fabrication and applications of copper sulfide (CuS) nanostructures

    NASA Astrophysics Data System (ADS)

    Shamraiz, Umair; Hussain, Raja Azadar; Badshah, Amin

    2016-06-01

    This review article presents different fabrication procedures (under the headlines of solvothermal routes, aerosol methods, solution methods and thermolysis), and applications (photocatalytic degradation, ablation of cancer cells, electrode material in lithium ion batteries and in gas sensing, organic solar cells, field emission properties, super capacitor applications, photoelectrochemical performance of QDSCs, photocatalytic reduction of organic pollutants, electrochemical bio sensing, enhanced PEC characteristics of pre-annealed CuS film electrodes) of copper sulfide (Covellite).

  8. A facile synthesis of copper sulfides composite with lithium-storage properties

    NASA Astrophysics Data System (ADS)

    Wang, Xuxiang; Wang, Yunhui; Li, Xue; Liu, Bo; Zhao, Jinbao

    2015-05-01

    Copper sulfides are synthesized by heating a mixture of copper and sulfur powders in different stoichiometries in N-methyl-2-pyrrolidinone (NMP) solvent. All the electrodes show excellent electrochemical performance, especially 'copper excess' copper sulfides electrodes. These electrodes can be charged and discharged at high rate, with good capacity retention. The electrochemical reaction mechanism of copper sulfides during discharge-charge process is investigated. It is most likely that all of S element in the copper excess electrode would transfer into a crystal of Cu2S during charge-discharge cycles, which corresponded to a single electrochemical reaction and showed excellent cycling and rate performance. These encouraging results indicate that copper-excess copper sulfides could be a promising anode material for lithium batteries with high rate capability.

  9. Multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates.

    SciTech Connect

    Chen, Ken Shuang

    2004-11-01

    This report documents the author's efforts in the deterministic modeling of copper-sulfidation corrosion on non-planar substrates such as diodes and electrical connectors. A new framework based on Goma was developed for multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates. In this framework, the moving sulfidation front is explicitly tracked by treating the finite-element mesh as a pseudo solid with an arbitrary Lagrangian-Eulerian formulation and repeatedly performing re-meshing using CUBIT and re-mapping using MAPVAR. Three one-dimensional studies were performed for verifying the framework in asymptotic regimes. Limited model validation was also carried out by comparing computed copper-sulfide thickness with experimental data. The framework was first demonstrated in modeling one-dimensional copper sulfidation with charge separation. It was found that both the thickness of the space-charge layers and the electrical potential at the sulfidation surface decrease rapidly as the Cu{sub 2}S layer thickens initially but eventually reach equilibrium values as Cu{sub 2}S layer becomes sufficiently thick; it was also found that electroneutrality is a reasonable approximation and that the electro-migration flux may be estimated by using the equilibrium potential difference between the sulfidation and annihilation surfaces when the Cu{sub 2}S layer is sufficiently thick. The framework was then employed to model copper sulfidation in the solid-state-diffusion controlled regime (i.e. stage II sulfidation) on a prototypical diode until a continuous Cu{sub 2}S film was formed on the diode surface. The framework was also applied to model copper sulfidation on an intermittent electrical contact between a gold-plated copper pin and gold-plated copper pad; the presence of Cu{sub 2}S was found to raise the effective electrical resistance drastically. Lastly, future research needs in modeling atmospheric copper sulfidation are discussed.

  10. Aqueous synthesis of PEGylated copper sulfide nanoparticles for photoacoustic imaging of tumors

    NASA Astrophysics Data System (ADS)

    Ding, Ke; Zeng, Jianfeng; Jing, Lihong; Qiao, Ruirui; Liu, Chunyan; Jiao, Mingxia; Li, Zhen; Gao, Mingyuan

    2015-06-01

    By integrating high imaging sensitivity and high resolution in a single modality, photoacoustic (PA) imaging emerges as a promising diagnostic tool for clinical applications. Benefiting from the absorption in the near-infrared region (NIR), copper sulfide nanoparticles (NPs) as a contrast agent are potentially useful for increasing the sensitivity of PA imaging. However, the aqueous synthesis of size-tunable, biocompatible and colloidally stable copper sulfide NPs remains challenging due to the intrinsic dipole-dipole interactions among particles. In this work, aqueous synthesis of PEGylated copper sulfide NPs with controllable size between 3 and 7 nm was developed. The particle size-dependent contrast enhancement effect of the copper sulfide NPs for PA imaging was carefully studied both in vitro and in vivo. Although the contrast enhancement effect of the copper sulfide NPs is proportional to particle size, the in vivo studies revealed that copper sulfide NPs smaller than 5 nm presented higher tumor imaging performance, especially at the tumor boundary site, which was further discussed in combination with the pharmacokinetic behaviors of differently sized particles.By integrating high imaging sensitivity and high resolution in a single modality, photoacoustic (PA) imaging emerges as a promising diagnostic tool for clinical applications. Benefiting from the absorption in the near-infrared region (NIR), copper sulfide nanoparticles (NPs) as a contrast agent are potentially useful for increasing the sensitivity of PA imaging. However, the aqueous synthesis of size-tunable, biocompatible and colloidally stable copper sulfide NPs remains challenging due to the intrinsic dipole-dipole interactions among particles. In this work, aqueous synthesis of PEGylated copper sulfide NPs with controllable size between 3 and 7 nm was developed. The particle size-dependent contrast enhancement effect of the copper sulfide NPs for PA imaging was carefully studied both in vitro and in

  11. Electrically Conducting Polymer-Copper Sulphide Composite Films, Preparation by Treatment of Polymer-Copper (2) Acetate Composites with Hydrogen Sulfide

    NASA Technical Reports Server (NTRS)

    Yamamoto, Takakazu; Kamigaki, Takahira; Kubota, Etsuo

    1988-01-01

    Polymer copper sulfide composite films were prepared by treatment of polymer poly(vinyl chloride), poly(acrylonitrile), copolymer of vinyl chloride and vinyl acetate (90:10), and ABS resin copper (2) acetate composites with hydrogen sulfide. The films showed electrical conductivity higher than 0.015 S/cm when they contained more than 20 wt percent of copper sulfide. A poly(acrylonitrile)-copper sulfide composite film containing 40 to 50 wt percent of copper sulfide showed electrical conductivity of 10 to 150.0 S/cm and had relatively high mechanical strength to be used in practical purposes.

  12. Beneficiation of flotation tailing from Polish copper sulfide ores

    SciTech Connect

    Luszczkiewicz, A.; Sztaba, K.S.

    1995-12-31

    Flotation tailing of Polish copper sulfide ores represents more than 90% of the mass of run-of-mine ore. The tailing contains mainly quartz, dolomite, clay minerals, traces of sulfides, and some accessory minerals. Almost all minerals of the tailing are well liberated and, therefore, any further beneficiation process applied to the tailing is expected to be inexpensive. In this work, results of investigations on utilization of flotation tailing using classification and gravity concentration are presented. It is shown that due to classification of flotation tailing in hydrocyclones, the coarse fraction becomes suitable material for gravity separation providing backfill material for underground mines as well as heavy minerals, a source of valuable rare elements. It was also found that heavy minerals separated by gravity methods contain a significant amount of rare elements such as zirconium, titanium, silver, rare earth metals, and uranium. The light fraction of the gravity separation contains well deslimed quartz particles and meets strict requirements for hydraulic filling material used for structural support in underground mines. Evaluation of the cost of the proposed technology indicated that investment to implement the method would provide a return within 2--4 years.

  13. Plasmonic copper sulfide nanocrystals exhibiting near-infrared photothermal and photodynamic therapeutic effects.

    PubMed

    Wang, Shunhao; Riedinger, Andreas; Li, Hongbo; Fu, Changhui; Liu, Huiyu; Li, Linlin; Liu, Tianlong; Tan, Longfei; Barthel, Markus J; Pugliese, Giammarino; De Donato, Francesco; Scotto D'Abbusco, Marco; Meng, Xianwei; Manna, Liberato; Meng, Huan; Pellegrino, Teresa

    2015-02-24

    Recently, plasmonic copper sulfide (Cu2-xS) nanocrystals (NCs) have attracted much attention as materials for photothermal therapy (PTT). Previous reports have correlated photoinduced cell death to the photothermal heat mechanism of these NCs, and no evidence of their photodynamic properties has been reported yet. Herein we have prepared physiologically stable near-infrared (NIR) plasmonic copper sulfide NCs and analyzed their photothermal and photodynamic properties, including therapeutic potential in cultured melanoma cells and a murine melanoma model. Interestingly, we observe that, besides a high PTT efficacy, these copper sulfide NCs additionally possess intrinsic NIR induced photodynamic activity, whereupon they generate high levels of reactive oxygen species. Furthermore, in vitro and in vivo acute toxic responses of copper sulfide NCs were also elicited. This study highlights a mechanism of NIR light induced cancer therapy, which could pave the way toward more effective nanotherapeutics. PMID:25603353

  14. VAPOR PHASE MERCURY SORPTION BY ORGANIC SULFIDE MODIFIED BIMETALLIC IRON-COPPER NANOPARTICLE AGGREGATES

    EPA Science Inventory

    Novel organic sulfide modified bimetallic iron-copper nanoparticle aggregate sorbent materials have been synthesized for removing elemental mercury from vapor streams at elevated temperatures (120-140 °C). Silane based (disulfide silane and tetrasulfide silane) and alkyl sulfide ...

  15. Effect of anions on selective solubilization of zinc and copper in bacterial leaching of sulfide ores.

    PubMed

    Harahuc, L; Lizama, H M; Suzuki, I

    2000-07-20

    Bacterial leaching of sulfide ores using Thiobacillus ferrooxidans, Thiobacillus thiooxidans, or a combination of the two was studied at various concentrations of specific anions. Selective zinc and copper solubilization was obtained by inhibiting iron oxidation without affecting sulfur/sulfide oxidation. Phosphate reduced iron solubilization from a pyrite (FeS(2))-sphalerite (ZnS) mixture without significantly affecting zinc solubilization. Copper leaching from a chalcopyrite (CuFeS(2))-sphalerite mixture was stimulated by phosphate, whereas chloride accelerated zinc extraction. In a complex sulfide ore containing pyrite, chalcopyrite, and sphalerite, both phosphate and chloride reduced iron solubilization and increased copper extraction, whereas only chloride stimulated zinc extraction. Maximum leaching obtained was 100% zinc and 50% copper. Time-course studies of copper and zinc solubilization suggest the possibility of selective metal recovery following treatment with specific anions. PMID:10861398

  16. Hollow Copper Sulfide Nanoparticle-Mediated Transdermal Drug Delivery

    PubMed Central

    Ramadan, Samy; Guo, Liangran; Li, Yajuan; Yan, Bingfang; Lu, Wei

    2012-01-01

    Nanoparticles with strong optical absorption at near-infrared (NIR) wavelengths can efficiently convert optical energy into thermal energy, and have shown multimodality in biological and biomedical applications. In this work, a new type of thermal ablation-enhanced transdermal delivery methodology is developed based on hollow copper sulfide nanoparticles (HCuSNPs) with intense photothermal coupling effects. Application of nanosecond-pulsed NIR laser allows rapid heating of the nanoparticles and instantaneous heat conduction. This provides very short periods of time but extremely high temperatures (estimated over 100°C) in local regions, with focused thermal ablation of the stratum corneum. Because the discontinuous light from the pulsed laser minimized heat accumulation, the average temperature of the irradiated skin area only increases to ~40–50°C. The extent of thermal ablation of skin, i.e. removal of the stratum corneum, viable epidermis, or the dermis, can be controlled by adjusting the laser power. The skin disruption by HCuSNP-mediated photothermal ablation significantly increases the permeability of macromolecule drugs such as human growth hormone, providing effective and controlled percutaneous delivery. This technique offers compelling opportunities to overcome low oral bioavailability of small- and large-molecular-weight drugs, avoiding the pain and inconvenience of long-term s.c. injections while enabling sustained and controlled delivery. PMID:22829400

  17. Crystal structure controlled synthesis and characterization of copper sulfide nanoparticles

    NASA Astrophysics Data System (ADS)

    Senthilkumar, M.; Babu, S. Moorthy

    2016-05-01

    Phase pure, controlled crystal structure of digenite (Cu9S5) copper sulfide nanoparticles were synthesized by hot injection method at the temperature of 180°C. The mixture of Oleylamine, 1-Octadecene and 1-Dodecanethiol were taken as solvent as well as capping agents. The effect of the mixture of solvents on the phase formation and morphology of the synthesized nanoparticles were analysed. The nanocrystals were characterized using X-Ray diffraction (XRD) which confirms the presence of single phase rhombohedral digenite Cu9S5 NPs, Morphological analysis clearly depicts the formation of hexagonal faceted Cu9S5 NPs, Energy dispersive X-ray absorption spectroscopy (EDS) reveals the stoichiometric ratio of 1.8:1 for synthesized NPs. From the UV-Vis absorption spectroscopy the bandgap value of Cu1.8S is found to be 1.71 eV. The presence of capping agents along the surface of the Cu9S5 NPs was confirmed from FTIR analysis.

  18. VAPOR PHASE MERCURY SORPTION BY ORGANIC-SULFIDE COATED BIMETALLIC IRON-COPPER NANOPARTICLE AGGREGATES

    EPA Science Inventory

    Tetra sulfide silane coated iron-copper nano-particle aggregates are found to be potentially very high capacity sorbents for vapor phase mercury capture. High equilibrium capacities were obtained for the silane coated iron copper nano-aggregate sorbent at 70 oC and 120 oC. Even a...

  19. Phage-directed synthesis of copper sulfide: structural and optical characterization

    NASA Astrophysics Data System (ADS)

    Shahriar Zaman, Mohammed; Moon, Chung Hee; Bozhilov, Krassimir N.; Haberer, Elaine D.

    2013-08-01

    The growth of crystalline copper sulfide using a viral template was investigated using sequential incubation in CuCl2 and Na2S precursors. Non-specific electrostatic attraction between a genetically-modified M13 bacteriophage and copper cations in the CuCl2 precursor caused phage agglomeration and bundle formation. Following the addition of Na2S, polydisperse nanocrystals 2-7 nm in size were found along the length of the viral scaffold. The structure of the copper sulfide material was identified as cubic anti-fluorite type Cu1.8S, space group F m\\bar {3}m. Strong interband absorption was observed within the ultraviolet to visible range with an onset near 800 nm. Furthermore, free carrier absorption, associated with the localized surface plasmon resonance of the copper sulfide nanocrystals, was seen in the near infrared with absorbance maxima at 1060 nm and 3000 nm, respectively.

  20. From Ultrafine Thiolate-Capped Copper Nanoclusters toward Copper Sulfide Nanodiscs: A Thermally Activated Evolution Route

    SciTech Connect

    Mott, Derrick; Yin, Jun; Engelhard, Mark H.; Loukrakpam, Rameshwori; Chang, Paul; Miller, George; Bae, In-Tae; Das, N. C.; Wang, Chong M.; Luo, Jin; Zhong, Chuan-Jian

    2010-01-12

    In this report we show that the size, shape, and composition of pre-synthesized metal nanoparticles can be engineered through exploiting concurrent interparticle coalescence and interfacial copper-thiolate cleavage under a thermally-activated evolution process. This concept is demonstrated by thermally-activated processing of ultrafine (~0.5 nm) copper nanoparticles encapsulated with thiolate monolayer (Cun(SR)m) toward copper sulfide nanodiscs with controllable sizes and shapes. It involved a thermally-activated coalescence of Cun(SR)m nanoclusters accompanied by interfacial Cu-S cleavage towards the formation of Cu2S nanocrystals with well-defined nanodisc shapes with an average diameter and thickness ranging from 10.7 ±1.4 nm and 5.5 ±0.5 nm (aspect ratio ~2) to 31.2 ±4.3 nm and 3.9 ±0.4 nm (aspect ratio ~7) depending on the thermal processing parameters. These nanodiscs are stable and display remarkable ordering upon self-assembly. The abilities to create the ultrafine copper nanoclusters and to enable them to undergo a thermally-activated coalescence and a concurrent Cu-S bond cleavage toward the formation of Cu2S nanodiscs is entirely new. The viability of fine tuning the size and shape of the Cu2S nanocrystals by controlling the relative binding strength of thiolates, the C-S cleavage reactivity, and the interparticle coalescence activity, and their potential applications in electronic, sensing and photochemical devices are also discussed.

  1. Sonochemical preparation of copper sulfides with different phases in aqueous solutions

    SciTech Connect

    Kristl, Matjaž; Hojnik, Nuša; Gyergyek, Sašo; Drofenik, Miha

    2013-03-15

    Highlights: ► Sonochemical preparation of copper sulfides in aqueous solutions is reported. ► CuS and Cu{sub 2}S nanoparticles with crystallite sizes between 7 and 18 nm were obtained. ► Crystallite size can be changed using different complexing agents. ► Thermal behavior was studied by TG and XRD measurements. - Abstract: There is a growing interest in the synthesis of nanostructured copper sulfides due to their ability to form compounds with various stoichiometries. We report a sonochemical route for the preparation of copper sulfides with different compositions in aqueous solutions, using different, general and convenient copper sources such as copper acetate, copper hydroxide or basic copper carbonate and thiourea or thioacetamide as sulfur precursors under ambient air. Phase analysis, purity and morphology of the products were studied by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The results revealed that nanoparticles of covellite, CuS, with crystallite sizes between 7 and 18 nm can be obtained by using different precursors and complexing agents and that chalcocite, Cu{sub 2}S, can also be prepared sonochemically.

  2. Analytical modeling of localized surface plasmon resonance in heterostructure copper sulfide nanocrystals

    SciTech Connect

    Caldwell, Andrew H.; Ha, Don-Hyung; Robinson, Richard D.; Ding, Xiaoyue

    2014-10-28

    Localized surface plasmon resonance (LSPR) in semiconductor nanocrystals is a relatively new field of investigation that promises greater tunability of plasmonic properties compared to metal nanoparticles. A novel process by which the LSPR in semiconductor nanocrystals can be altered is through heterostructure formation arising from solution-based cation exchange. Herein, we describe the development of an analytical model of LSPR in heterostructure copper sulfide-zinc sulfide nanocrystals synthesized via a cation exchange reaction between copper sulfide (Cu{sub 1.81}S) nanocrystals and Zn ions. The cation exchange reaction produces dual-interface, heterostructure nanocrystals in which the geometry of the copper sulfide phase can be tuned from a sphere to a thin disk separating symmetrically-grown sulfide (ZnS) grains. Drude model electronic conduction and Mie-Gans theory are applied to describe how the LSPR wavelength changes during cation exchange, taking into account the morphology evolution and changes to the local permittivity. The results of the modeling indicate that the presence of the ZnS grains has a significant effect on the out-of-plane LSPR mode. By comparing the results of the model to previous studies on solid-solid phase transformations of copper sulfide in these nanocrystals during cation exchange, we show that the carrier concentration is independent of the copper vacancy concentration dictated by its atomic phase. The evolution of the effective carrier concentration calculated from the model suggests that the out-of-plane resonance mode is dominant. The classical model was compared to a simplified quantum mechanical model which suggested that quantum mechanical effects become significant when the characteristic size is less than ∼8 nm. Overall, we find that the analytical models are not accurate for these heterostructured semiconductor nanocrystals, indicating the need for new model development for this emerging field.

  3. The effects of varying humidity on copper sulfide film formation.

    SciTech Connect

    Mayer, Thomas Michael; Missert, Nancy A.; Barbour, John Charles; Sullivan, John Patrick; Copeland, Robert Guild; Campin, Michael J.

    2004-02-01

    Detailed experiments involving extensive high resolution transmission electron microscopy (TEM) revealed significant microstructural differences between Cu sulfides formed at low and high relative humidity (RH). It was known from prior experiments that the sulfide grows linearly with time at low RH up to a sulfide thickness approaching or exceeding one micron, while the sulfide initially grows linearly with time at high RH then becomes sub-linear at a sulfide thickness less than about 0.2 microns, with the sulfidation rate eventually approaching zero. TEM measurements of the Cu2S morphology revealed that the Cu2S formed at low RH has large sized grains (75 to greater than 150 nm) that are columnar in structure with sharp, abrupt grain boundaries. In contrast, the Cu2S formed at high RH has small equiaxed grains of 20 to 50 nm in size. Importantly, the small grains formed at high RH have highly disordered grain boundaries with a high concentration of nano-voids. Two-dimensional diffusion modeling was performed to determine whether the existence of localized source terms at the Cu/Cu2S interface could be responsible for the suppression of Cu sulfidation at long times at high RH. The models indicated that the existence of static localized source terms would not predict the complete suppression of growth that was observed. Instead, the models suggest that the diffusion of Cu through Cu2S becomes restricted during Cu2S formation at high RH. The leading speculation is that the extensive voiding that exists at grain boundaries in this material greatly reduces the flux of Cu between grains, leading to a reduction in the rate of sulfide film formation. These experiments provide an approach for adding microstructural information to Cu sulfidation rate computer models. In addition to the microstructural studies, new micro-patterned test structures were developed in this LDRD to offer insight into the point defect structure of Cu2S and to permit measurement of surface reaction

  4. Kinetics of Copper Removal from Sulfidized Molybdenite Concentrates by Pressure Leaching

    NASA Astrophysics Data System (ADS)

    Padilla, Rafael; Opazo, Cristian; Ruiz, Maria C.

    2015-02-01

    Molybdenite concentrates produced from porphyry copper deposits contain copper as an impurity in variable quantities. To produce a high-grade molybdenite concentrate, a chemical purification method is normally practiced. In this paper, a new alternative for the copper elimination from molybdenite concentrates containing chalcopyrite by sulfidation of the molybdenite concentrate and subsequent pressure leaching in sulfuric acid-oxygen media is discussed. The results indicated that copper contained in sulfidized molybdenite concentrates can be dissolved effectively by pressure leaching at low temperature ranging from 373 K to 423 K (100 °C to 150 °C) and low oxygen pressure (303.98 to 1013.25 kPa) with negligible dissolution of molybdenum. The final molybdenite contained less than 0.2 pct Cu which is appropriate for marketing. Temperature and oxygen partial pressure have both significant influence on the copper dissolution. The kinetics of the copper dissolution was analyzed using the shrinking core model with surface chemical control. The calculated activation energy was 51 kJ/mol in the range of 373 K to 423 K (100 °C to 150 °C). The copper dissolution rate is of zero order with respect to hydrogen ion concentration, and first order with respect to oxygen partial pressure.

  5. Recovery of cobalt and copper from complex sulfide concentrates

    SciTech Connect

    Dannenberg, R.O.; Gardner, P.C.; Crane, S.R.; Seidel, D.C.

    1987-01-01

    The Bureau conducted bench-scale research on a process for treating cobaltite concentrates, comprising (1) oxidative pressure leaching, (2) jarosite precipitation followed by H/sub 2/O/sub 2/ oxidation and pH control to remove iron and arsenic, (3) copper solvent extraction with a mixed hydroxyoxime-amine extractant, (4) copper electrowinning from recirculating acidic strip liquor, (5) selective cobalt extraction from copper solvent extraction raffinate with a phosphinic and extractant, and (6) electrowinning of cobalt from a recirculating weak acid strip liquor. Overall cobalt and copper recoveries were 91.7 and 84.1 pct, respectively. Electrowon products assayed 99.8 pct Co and 99.89 ct Cu.

  6. Solid-solid phase transformations induced through cation exchange and strain in 2D heterostructured copper sulfide nanocrystals.

    PubMed

    Ha, Don-Hyung; Caldwell, Andrew H; Ward, Matthew J; Honrao, Shreyas; Mathew, Kiran; Hovden, Robert; Koker, Margaret K A; Muller, David A; Hennig, Richard G; Robinson, Richard D

    2014-12-10

    We demonstrate dual interface formation in nanocrystals (NCs) through cation exchange, creating epitaxial heterostructures within spherical NCs. The thickness of the inner-disk layer can be tuned to form two-dimensional (2D), single atomic layers (<1 nm). During the cation exchange reaction from copper sulfide to zinc sulfide (ZnS), we observe a solid-solid phase transformation of the copper sulfide phase in heterostructured NCs. As the cation exchange reaction is initiated, Cu ions replaced by Zn ions at the interfaces are accommodated in intrinsic Cu vacancy sites present in the initial roxbyite (Cu1.81S) phase of copper sulfide, inducing a full phase transition to djurleite (Cu1.94S)/low chalcocite (Cu2S), a more thermodynamically stable phase than roxbyite. As the reaction proceeds and reduces the size of the copper sulfide layer, the epitaxial strain at the interfaces between copper sulfide and ZnS increases and is maximized for a copper sulfide disk ∼ 5 nm thick. To minimize this strain energy, a second phase transformation occurs back to the roxbyite phase, which shares a similar sulfur sublattice to wurtzite ZnS. The observation of a solid-solid phase transformation in our unique heterostructured NCs provides a new pathway to control desired phases and an insight into the influence of cation exchange on nanoscale phase transitions in heterostructured materials. PMID:25337657

  7. Thermochemical chlorination of carbon indirectly driven by an unexpected sulfide of copper with inorganic chloride.

    PubMed

    Fujimori, Takashi; Takaoka, Masaki

    2011-12-15

    Unintentional anthropogenic thermal chlorination of carbon is known to be a contributor to global environmental pollution of organochlorine compounds. We found unexpected, serious chlorination of carbon promoted by a "sulfide" of copper, which has been generally thought of and studied as an inactive metal catalyst. Our quantitative and X-ray spectroscopic results show that a fraction of cupric sulfide indirectly promoted thermochemical solid-phase formation of a large quantity of organochlorine compounds such as polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls, and benzenes that used inactive inorganic chloride as chlorine storage, which partly caused environmental pollution by organochlorine compounds. PMID:22004834

  8. Removal of copper from carbon-saturated iron with an aluminum sulfide ferrous sulfide flux.

    SciTech Connect

    Cohen, A.; Blander, M.; Energy Technology

    1998-04-01

    Scrap iron and steel have long been considered as resources in the steelmaking industry, and their value is largely determined by the impurity content. Copper is a particularly troublesome impurity because of its role in causing hot shortness and should be kept below ==0.1 wt pct. A method for reducing copper content in steel to <0.1 wt pct could lead to increased use of lower-quality scrap.

  9. Banded sulfide-magnetite ores of Mauk copper massive sulfide deposit, Central Urals: Composition and genesis

    NASA Astrophysics Data System (ADS)

    Safina, N. P.; Maslennikov, V. V.; Maslennikova, S. P.; Kotlyarov, V. A.; Danyushevsky, L. V.; Large, R. R.; Blinov, I. A.

    2015-05-01

    The results of investigation of metamorphosed sulfide-magnetite ores from the Mauk deposit located within the Main Ural Fault at the junction of Tagil and Magnitogorsk massive sulfide zones are discussed. The ore-hosting sequence comprises metamorphic rocks formed from basalt, carbonaceous and carbonaceous-cherty siltstone, and lenticular serpentinized ultramafic bodies. The ores of the deposit are represented by banded varieties and less frequent breccia. The clastic origin of the banded ore is indicated by load casts at the bottom of sulfide beds, alternation of sulfide and barren beds, and the truncation of the growth zones of pyrite crystals. Pyrite, pyrrhotite, chalcopyrite, sphalerite, and magnetite are the major minerals of the banded ores. The internal structure of the listed minerals testifies to the deep metamorphic recrystallization of primary hydrothermal-sedimentary ores accompanied with deformation. Cubanite, pyrrhotite, mackinawite, greigite, and gold are enclosed in metacrysts of pyrite, magnetite, and chalcopyrite. The accessory minerals of the Pb-Bi-Te, Bi-Te, and Ag-Te systems as well as uraninite have been found at the Mauk deposit for the first time. Magnetite predominantly replaces pyrite and less frequently chalcopyrite, pyrrhotite, and gangue minerals. It was established that the major carriers of As and Co are crystals of metamorphic pyrite. Chalcopyrite is the major carrier of Zn, Sn, Te, Pb, Bi, and Ag. Admixture of Fe and Cu is typical of sphalerite, and Se and Ni are characteristic of pyrrhotite. Ti, V, Mn, Sb, As, Ba, and U are concentrated in magnetite. The banded ores of the Mauk deposit are suggested as having been transformed in several stages: diagenesis, anadiagenesis, epidiagenesis ( t < 300°C), and amphibolite facies metamorphism ( t > 500°C).

  10. Porous copper zinc tin sulfide thin film as photocathode for double junction photoelectrochemical solar cells.

    PubMed

    Dai, Pengcheng; Zhang, Guan; Chen, Yuncheng; Jiang, Hechun; Feng, Zhenyu; Lin, Zhaojun; Zhan, Jinhua

    2012-03-21

    Porous copper zinc tin sulfide (CZTS) thin film was prepared via a solvothermal approach. Compared with conventional dye-sensitized solar cells (DSSCs), double junction photoelectrochemical cells using dye-sensitized n-type TiO(2) (DS-TiO(2)) as the photoanode and porous p-type CZTS film as the photocathode shows an increased short circuit current, external quantum efficiency and power conversion efficiency. PMID:22322239

  11. Copper isotopic signature of the Tiegelongnan high-sulfidation copper deposit, Tibet: implications for its origin and mineral exploration

    NASA Astrophysics Data System (ADS)

    Duan, Jilin; Tang, Juxing; Li, Yubin; Liu, Sheng-Ao; Wang, Qin; Yang, Chao; Wang, Yiyun

    2015-12-01

    We report the copper isotopic composition of Cu sulfides in the Tiegelongnan high-sulfidation (HS) copper deposit, Tibet, and investigate the possible application of Cu isotopes to mineral exploration. The copper isotopic values of samples from four drill holes display consistent progressive increase with depth to 400 m below surface, with an overall variation of δ65Cu of up to 7.60‰ (-4.76 to 2.84‰). Such a large range is very different from that observed in Cu porphyry deposits which commonly exhibit a small δ65Cu range (<1‰), with decreasing values with depth. The large δ65Cu variation is likely of supergene origin and reflects strong leaching under oxidized conditions. The systematic increase of δ65Cu with depth can be explained by the release of isotopically heavy Cu at the top and its transport downward, which is supported by the coupling of positive δ65Cu values with high Cu grade and the occurrence of both negative and positive δ65Cu values in two drill holes. Mass-balance consideration on the basis of Cu isotopes can indicate mineralized zones which have been eroded or have not been found yet. Such mineralized targets, if buried at depth, could be located using Cu isotopes.

  12. Copper isotopic signature of the Tiegelongnan high-sulfidation copper deposit, Tibet: implications for its origin and mineral exploration

    NASA Astrophysics Data System (ADS)

    Duan, Jilin; Tang, Juxing; Li, Yubin; Liu, Sheng-Ao; Wang, Qin; Yang, Chao; Wang, Yiyun

    2016-06-01

    We report the copper isotopic composition of Cu sulfides in the Tiegelongnan high-sulfidation (HS) copper deposit, Tibet, and investigate the possible application of Cu isotopes to mineral exploration. The copper isotopic values of samples from four drill holes display consistent progressive increase with depth to 400 m below surface, with an overall variation of δ65Cu of up to 7.60‰ (-4.76 to 2.84‰). Such a large range is very different from that observed in Cu porphyry deposits which commonly exhibit a small δ65Cu range (<1‰), with decreasing values with depth. The large δ65Cu variation is likely of supergene origin and reflects strong leaching under oxidized conditions. The systematic increase of δ65Cu with depth can be explained by the release of isotopically heavy Cu at the top and its transport downward, which is supported by the coupling of positive δ65Cu values with high Cu grade and the occurrence of both negative and positive δ65Cu values in two drill holes. Mass-balance consideration on the basis of Cu isotopes can indicate mineralized zones which have been eroded or have not been found yet. Such mineralized targets, if buried at depth, could be located using Cu isotopes.

  13. New Measurements of the Densities of Copper, Nickel, and Iron Sulfide Liquids

    NASA Astrophysics Data System (ADS)

    Mioduszewski, L.; Kress, V. C.

    2005-12-01

    Density measurements of sulfide liquids in the Fe-Ni-Cu-S-O system were performed from 1150°C-1250°C under controlled oxygen and sulfur fugacities. Measurements were made using the modified single bob (MSB) Archimedean method using zirconia ceramic bobs and crucibles. A 0.005mm resolution micrometer was attached to an elevator, which raised the crucible and melt relative to the free-hanging, stationary bob. A 0.001 g resolution analytical balance connected to a laptop computer continuously recorded the buoyancy as a function of crucible elevation. Densities were calculated by converting elevation to immersed volume and regressing the slope of buoyancy versus volume immersed. log(fO2) in the experiments ranged from -7.8 to -12.6 and log(fS2) ranged from -0.9 to -3.3. 38 successful sulfide liquid density measurements were performed, with values ranging from 3.8 g/cc to 6.6 g/cc. Regression of the resulting data suggests that a simple linear volume mixing model is adequate to represent the compositional dependence of density in copper- and nickel-sulfide liquids. A moderate positive excess mixing volume appears to be justified in iron-sulfide liquids. This result, along with high derived partial molar volumes for oxygen and sulfur components, are qualitatively consistent with the suggestion that increasing pressure will partition oxygen and sulfur out of the sulfide liquid during planetary accretion. The MSB density measurement also provides information on the relative magnitude of gas-zirconia and sulfide-zirconia surface energies. Assuming most of the observed variation results from sulfide chemistry it appears that oxidizing conditions significantly decrease sulfide-zirconia surface energies (increase wetting). If we can extrapolate this result to silicate minerals, this would suggest that oxidizing conditions will decrease wetting angle and thus increase the potential for sulfide segregation during planetary formation. We hope to test this hypothesis soon. Our

  14. Living cells imaging for copper and hydrogen sulfide by a selective "on-off-on" fluorescent probe.

    PubMed

    Qian, Yong; Lin, Jie; Liu, Tianbao; Zhu, Hailiang

    2015-01-01

    A novel highly selective and sensitive fluorescent probe (NJ1) had been designed and synthesized for Cu(2+) detection by fluorescence quenching mechanism, and then the enhancement of fluorescence intensity with the addition of hydrogen sulfide in complex NJ1Cu aqueous solution at physiological conditions were described. This "on-off-on" type fluorescence recognition system was a reversible process, which could be utilized to monitor copper ion and hydrogen sulfide based on a complex NJ1Cu formation-Cu(2+) displacement approach. Importantly, this real-time recognition process of Cu(2+) and hydrogen sulfide exhibited excellent anti-interference ability. In addition, this new fluorescent probe also has potential utility for Cu(2+) and hydrogen sulfide detection in living cells, providing a potential tool for investigating copper ion and hydrogen sulfide in living systems or environment. PMID:25476371

  15. Characterization of the molecular structure at modified polymer surfaces and polyphenylene sulfide/copper interphases

    SciTech Connect

    Webster, H.F. II.

    1992-01-01

    This research focused on the use of infrared reflection absorption spectroscopy (IRRAS) and x-ray photoelectron spectroscopy (XPS) to investigate the molecular structure of modified and unmodified thin films. The optical constants of polyphenylene sulfide (PPS) were determined and exact optical theory was utilized to simulate spectra for a variety of reflectance techniques. The surface modification of polystyrene, polyphenylene sulfide, and poly(arylene ether) phosphine oxides was also examined. A new technique, variable temperature reflection absorption spectroscopy (VTRAS) was developed as a method to investigate the reorganization of thin PPS films on a variety of substrates. Both the crystallization and melting temperatures could be determined for quenched coatings on a variety of substrates. While degradation under vacuum was not observed on chromium and aluminum surfaces, PPS films on the original ordered state after exposure to temperatures near 300[degrees]C. Spin coated films of polyetherimide were shown to be oriented after spin coating, and the relaxation to a more random state could also be observed by the VTRAS technique. Degradation of PPS films in air was examined and the diffusion of copper species into the bulk of the film with the formation of copper carboxylates was observed. Bonded PPS/copper laminates were investigated and the particular surface chemistry was crucial in determining the peel strength observed. Chemical oxidation with alkaline persulfate solutions resulted in a needle-like surface oxide morphology, and bond strengths were increased by this pretreatment method. The formation of excess cuprous sulfide at the interface was the most probable cause of poor adhesion in these systems. Foil pretreatment by thermal oxidation gave the highest peel strength, and exhibited the lowest amount of interfacial cuprous sulfide.

  16. Grain-to-Grain Compositional Variations and Phase Segregation in Copper-Zinc-Tin-Sulfide Films.

    PubMed

    Alvarez Barragan, Alejandro; Malekpour, Hoda; Exarhos, Stephen; Balandin, Alexander A; Mangolini, Lorenzo

    2016-09-01

    We have performed a rigorous investigation of the structure and composition of individual grains in copper-zinc-tin-sulfide (CZTS) films realized by sulfurization of a sputtered metal stack. Although on average close to the ideal CZTS stoichiometry, elemental analysis shows significant grain-to-grain variations in composition. High-resolution Raman spectroscopy indicates that this is accompanied by grain-to-grain structural variations as well. The intensity from the 337 cm(-1) Raman peak, generally assigned to the kesterite phase of CZTS, remains constant over a large area of the sample. On the other hand, signals from secondary phases at 376 cm(-1) (copper-tin-sulfide) and 351 cm(-1) (zinc-sulfide) show significant variation over the same area. These results confirm the great complexity inherent to this material system. Moreover, structural and compositional variations are recognized in the literature as a factor limiting the efficiency of CZTS photovoltaic devices. This study demonstrates how a seemingly homogeneous CZTS thin film can actually have considerable structural and compositional variations at the microscale, and highlights the need for routine microscale characterization in this material system. PMID:27538122

  17. Fabrication of a Functionally Graded Copper-Zinc Sulfide Phosphor

    PubMed Central

    Park, Jehong; Park, Kwangwon; Kim, Jongsu; Jeong, Yongseok; Kawasaki, Akira; Kwon, Hansang

    2016-01-01

    Functionally graded materials (FGMs) are compositionally gradient materials. They can achieve the controlled distribution of the desired characteristics within the same bulk material. We describe a functionally graded (FG) metal-phosphor adapting the concept of the FGM; copper (Cu) is selected as a metal and Cu- and Cl-doped ZnS (ZnS:Cu,Cl) is selected as a phosphor and FG [Cu]-[ZnS:Cu,Cl] is fabricated by a very simple powder process. The FG [Cu]-[ZnS:Cu,Cl] reveals a dual-structured functional material composed of dense Cu and porous ZnS:Cu,Cl, which is completely combined through six graded mediating layers. The photoluminescence (PL) of FG [Cu]-[ZnS:Cu,Cl] is insensitive to temperature change. FG [Cu]-[ZnS:Cu,Cl] also exhibits diode characteristics and photo reactivity for 365 nm -UV light. Our FG metal-phosphor concept can pave the way to simplified manufacturing of low-cost and can be applied to various electronic devices. PMID:26972313

  18. Fabrication of a Functionally Graded Copper-Zinc Sulfide Phosphor.

    PubMed

    Park, Jehong; Park, Kwangwon; Kim, Jongsu; Jeong, Yongseok; Kawasaki, Akira; Kwon, Hansang

    2016-01-01

    Functionally graded materials (FGMs) are compositionally gradient materials. They can achieve the controlled distribution of the desired characteristics within the same bulk material. We describe a functionally graded (FG) metal-phosphor adapting the concept of the FGM; copper (Cu) is selected as a metal and Cu- and Cl-doped ZnS (ZnS:Cu,Cl) is selected as a phosphor and FG [Cu]-[ZnS:Cu,Cl] is fabricated by a very simple powder process. The FG [Cu]-[ZnS:Cu,Cl] reveals a dual-structured functional material composed of dense Cu and porous ZnS:Cu,Cl, which is completely combined through six graded mediating layers. The photoluminescence (PL) of FG [Cu]-[ZnS:Cu,Cl] is insensitive to temperature change. FG [Cu]-[ZnS:Cu,Cl] also exhibits diode characteristics and photo reactivity for 365 nm -UV light. Our FG metal-phosphor concept can pave the way to simplified manufacturing of low-cost and can be applied to various electronic devices. PMID:26972313

  19. Fabrication of a Functionally Graded Copper-Zinc Sulfide Phosphor

    NASA Astrophysics Data System (ADS)

    Park, Jehong; Park, Kwangwon; Kim, Jongsu; Jeong, Yongseok; Kawasaki, Akira; Kwon, Hansang

    2016-03-01

    Functionally graded materials (FGMs) are compositionally gradient materials. They can achieve the controlled distribution of the desired characteristics within the same bulk material. We describe a functionally graded (FG) metal-phosphor adapting the concept of the FGM; copper (Cu) is selected as a metal and Cu- and Cl-doped ZnS (ZnS:Cu,Cl) is selected as a phosphor and FG [Cu]-[ZnS:Cu,Cl] is fabricated by a very simple powder process. The FG [Cu]-[ZnS:Cu,Cl] reveals a dual-structured functional material composed of dense Cu and porous ZnS:Cu,Cl, which is completely combined through six graded mediating layers. The photoluminescence (PL) of FG [Cu]-[ZnS:Cu,Cl] is insensitive to temperature change. FG [Cu]-[ZnS:Cu,Cl] also exhibits diode characteristics and photo reactivity for 365 nm -UV light. Our FG metal-phosphor concept can pave the way to simplified manufacturing of low-cost and can be applied to various electronic devices.

  20. Microbial Ecology Assessment of Mixed Copper Oxide/Sulfide Dump Leach Operation

    SciTech Connect

    Bruhn, D F; Thompson, D N; Noah, K S

    1999-06-01

    Microbial consortia composed of complex mixtures of autotrophic and heterotrophic bacteria are responsible for the dissolution of metals from sulfide minerals. Thus, an efficient copper bioleaching operation depends on the microbial ecology of the system. A microbial ecology study of a mixed oxide/sulfide copper leaching operation was conducted using an "overlay" plating technique to differentiate and identify various bacterial consortium members of the genera Thiobacillus, Leptospirillum, Ferromicrobium, and Acidiphilium. Two temperatures (30C and 45C) were used to select for mesophilic and moderately thermophilic bacteria. Cell numbers varied from 0-106 cells/g dry ore, depending on the sample location and depth. After acid curing for oxide leaching, no viable bacteria were recovered, although inoculation of cells from raffinate re-established a microbial population after three months. Due to the low pH of the operation, very few non-iron-oxidizing acidophilic heterotrophs were recovered. Moderate thermophiles were isolated from the ore samples. Pregnant liquor solutions (PLS) and raffinate both contained a diversity of bacteria. In addition, an intermittently applied waste stream that contained high levels of arsenic and fluoride was tested for toxicity. Twenty vol% waste stream in PLS killed 100% of the cells in 48 hours, indicating substantial toxicity and/or growth inhibition. The data indicate that bacteria populations can recover after acid curing, and that application of the waste stream to the dump should be avoided. Monitoring the microbial ecology of the leaching operation provided significant information that improved copper recovery.

  1. Thin films of copper antimony sulfide: A photovoltaic absorber material

    SciTech Connect

    Ornelas-Acosta, R.E.; Shaji, S.; Avellaneda, D.; Castillo, G.A.; Das Roy, T.K.; Krishnan, B.

    2015-01-15

    Highlights: • CuSbS{sub 2} thin films were prepared by heating Sb{sub 2}S{sub 3}/Cu layers. • Analyzed the structure, composition, optical, and electrical properties. • PV structures: glass/SnO{sub 2}:F/n-CdS/p-CuSbS{sub 2}/C/Ag were formed at different conditions. • The PV parameters (J{sub sc}, V{sub oc}, and FF) were evaluated from the J–V characteristics. • J{sub sc}: 0.52–3.20 mA/cm{sup 2}, V{sub oc}:187–323 mV, FF: 0.27–0.48 were obtained. - Abstract: In this work, we report preparation and characterization of CuSbS{sub 2} thin films by heating glass/Sb{sub 2}S{sub 3}/Cu layers and their use as absorber material in photovoltaic structures: glass/SnO{sub 2}:F/n-CdS/p-CuSbS{sub 2}/C/Ag. The Sb{sub 2}S{sub 3} thin films of 600 nm were prepared by chemical bath deposition on which copper thin films of 50 nm were thermally evaporated, and the glass/Sb{sub 2}S{sub 3}/Cu multilayers were heated in vacuum at different temperatures. X-ray diffraction analysis showed the formation of orthorhombic CuSbS{sub 2} after heating the precursor layers. Studies on identification and chemical state of the elements were done using X-ray photoelectron spectroscopy. The optical band gap of the CuSbS{sub 2} thin films was 1.55 eV and the thin films were photoconductive. The photovoltaic parameters of the devices using CuSbS{sub 2} as absorber and CdS as window layer were evaluated from the J–V curves, yielding J{sub sc}, V{sub oc}, and FF values in the range of 0.52–3.20 mA/cm{sup 2}, 187–323 mV, and 0.27–0.48, respectively, under illumination of AM1.5 radiation.

  2. Development of copper sulfide/cadmium sulfide thin-film solar cells

    SciTech Connect

    Szedon, J.R.; Biter, W.J.; Abel, J.A.; Dickey, H.C.; Shirland, F.A.

    1981-02-27

    The purpose of this work has been to identify aspects of cell fabrication and treatment which are critical for achieving high efficiency Cu/sub 2/S/CdS solar cells. In approaching the problem several comparisons were made of the effects of specific steps in two methods of cell fabrication. These methods had previously given cells of about 6% and a maximum of 9% efficiency. Three areas requiring special attention and specific means to achieve acceptable results were identified. (1) The Cu/sub 2/S/CdS heterojunction area must be minimized. If single source evaporations of CdS are made on substrates whose temperatures (approx. 220/sup 0/C) are monitored and controlled using welded thermocouples, the CdS films will have adequately large grains (grain diameter greater than or equal to 2 ..mu..m) and will not develop significant etch pits during texturing in a mild etchant solution. (2) The termination of the wet barrier processing steps must be done carefully. An acceptable termination involves minimizing the amount of cuprous chloride retained on the cell surface during transfer to a rinsing stage while providing adequate exclusion of air from the space above the surface of the cuprous chloride solution. (3) Once formed, the Cu/sub 2/S layer should not be exposed to high temperatures (>100/sup 0/C) for long periods of time (> 5 min) if surface adsorbed moisture or oxygen are present. Heat treatments in ampoules under flowing hydrogen atmospheres should be preceded and followed by periods of at least 30 minutes at room temperature in the reducing ambient. If all these precautions are taken, wet chemical barrier processing of thermally evaporated CdS films on zinc-plated copper foil substrates yields cells of nearly 8% conversion efficiency without AR coating.

  3. Development of copper sulfide/cadmium sulfide thin-film solar cells

    SciTech Connect

    Szedon, J. R.; Biter, W. J.; Dickey, H. C.

    1982-03-08

    The most important accomplishments during this period were to demonstrate and to elucidate further the complex effects that occur during the aging of Cu/sub 2/S/CdS thin-film solar cells in flowing wet oxygen. There are two distinct effects. At constant illumination, the short-circuit current of cells aged at room temperature consistently decreases with time. The second effect, related to diode opposing current, is more involved and may result from several competing mechanisms. Over the short term (approx. 4 to 5 hours), the magnitude of diode opposing current decreases. After approx. 20 hours of aging, opposing current generally returns to the level achieved after hydrogen annealing which immediately preceded the aging sequence. Optical measurements of the spectral transmission of the Cu/sub 2/S layers in a cell content have been made using a silicon detector epoxied to the back of a CdS cell after the copper foil substrate was removed. There is no significant change in Cu/sub 2/S transmission behavior for wavelengths ranging from 525 to 1000 nm during wet-oxygen aging for periods of 2 to 36 hours. This suggests that the decrease in J/sub SC/ at constant illumination, for the aging experiments in a flowing wet-oxygen ambient, arises because of changes in minority-carrier transport properties of the Cu/sub 2/S. Before developing a method for using an epoxied silicon detector to measure optical behavior of the Cu/sub 2/S layer, we explored the possibility of using a junction-containing wafer of silicon as a substrate for deposited CdS films. Some monolithic structures were successfully fabricated. Comparisons were made of CdS grain structure details in the junction detector area and in an adjacent metallized area.

  4. Nontoxic and abundant copper zinc tin sulfide nanocrystals for potential high-temperature thermoelectric energy harvesting.

    PubMed

    Yang, Haoran; Jauregui, Luis A; Zhang, Genqiang; Chen, Yong P; Wu, Yue

    2012-02-01

    Improving energy/fuel efficiency by converting waste heat into electricity using thermoelectric materials is of great interest due to its simplicity and reliability. However, many thermoelectric materials are composed of either toxic or scarce elements. Here, we report the experimental realization of using nontoxic and abundant copper zinc tin sulfide (CZTS) nanocrystals for potential thermoelectric applications. The CZTS nanocrystals can be synthesized in large quantities from solution phase reaction and compressed into robust bulk pellets through spark plasma sintering and hot press while still maintaining nanoscale grain size inside. Electrical and thermal measurements have been performed from 300 to 700 K to understand the electron and phonon transports. Extra copper doping during the nanocrystal synthesis introduces a significant improvement in the performance. PMID:22214524

  5. Bioflotation of sulfide minerals with Acidithiobacillus ferrooxidans in relation to copper activation and surface oxidation.

    PubMed

    Pecina-Treviño, E T; Ramos-Escobedo, G T; Gallegos-Acevedo, P M; López-Saucedo, F J; Orrantia-Borunda, E

    2012-08-24

    Surface oxidation of sulfides and copper (Cu) activation are 2 of the main processes that determine the efficiency of flotation. The present study was developed with the intention to ascertain the role of the phenomena in the biomodification of sulfides by Acidithiobacillus ferrooxidans culture (cells and growth media) and their impact in bioflotation. Surface characteristics of chalcopyrite, sphalerite, and pyrrhotite, alone and in mixtures, after interaction with A. ferrooxidans were evaluated. Chalcopyrite floatability was increased substantially by biomodification, while bacteria depressed pyrrhotite floatability, favoring separation. The results showed that elemental sulfur concentration increased because of the oxidation generated by bacterial cells, the effect is intensified by the Fe(III) left in the culture and by galvanic contact. Acidithiobacillus ferrooxidans culture affects the Cu activation of sphalerite. The implications of elemental sulfur concentration and Cu activation of sphalerite are key factors that must be considered for the future development of sulfide bioflotation processes, since the depressive effect of cells could be counteracted by elemental sulfur generation. PMID:22920540

  6. Copper sulfides for rechargeable lithium batteries: Linking cycling stability to electrolyte composition

    NASA Astrophysics Data System (ADS)

    Jache, Birte; Mogwitz, Boris; Klein, Franziska; Adelhelm, Philipp

    2014-02-01

    Copper sulfides are attractive electrode materials as their reaction with lithium offers high capacity and energy density. However, the reversibility is poor and (nano)structuring is considered necessary to achieve moderate improvements. In contrast, we show in this study that the electrolyte is a major factor that governs the reversibility of the cell reaction. All our experiments were done with commercially available copper sulfides (CuS and Cu2S) without any special nanostructure. Different electrolyte compositions were tested among LiPF6 in EC/DMC and LiTFSI in DOL/DME. While rapid capacity fading is found in cells containing carbonate-based electrolytes, cells with ether-based electrolytes show a much better electrochemical performance. For a mixture of 1 M LiTFSI in DOL/DME, Cu2S can be cycled with capacities of around 200 mAh g-1 for more than 150 cycles with coulombic efficiencies >98.4%, for example. The improved stability in the ether-based electrolyte further allowed us to study how the discharge and charge voltage change during prolonged cycling. Our study underlines that improvements in the Li/CuS and Li/Cu2S system are still possible by very simple measures, but further studies on the complex Li-Cu-S phase behavior are necessary to understand the discharging and especially the charging mechanisms.

  7. Synthesis, Deposition, and Microstructure Development of Thin Films Formed by Sulfidation and Selenization of Copper Zinc Tin Sulfide Nanocrystals

    NASA Astrophysics Data System (ADS)

    Chernomordik, Boris David

    Significant reduction in greenhouse gas emission and pollution associated with the global power demand can be accomplished by supplying tens-of-terawatts of power with solar cell technologies. No one solar cell material currently on the market is poised to meet this challenge due to issues such as manufacturing cost, material shortage, or material toxicity. For this reason, there is increasing interest in efficient light-absorbing materials that are comprised of abundant and non-toxic elements for thin film solar cell. Among these materials are copper zinc tin sulfide (Cu2ZnSnS4, or CZTS), copper zinc tin selenide (Cu2ZnSnSe4, or CZTSe), and copper zinc tin sulfoselenide alloys [Cu2ZnSn(SxSe1-x )4, or CZTSSe]. Laboratory power conversion efficiencies of CZTSSe-based solar cells have risen to almost 13% in less than three decades of research. Meeting the terawatt challenge will also require low cost fabrication. CZTSSe thin films from annealed colloidal nanocrystal coatings is an example of solution-based methods that can reduce manufacturing costs through advantages such as high throughput, high material utilization, and low capital expenses. The film microstructure and grain size affects the solar cell performance. To realize low cost commercial production and high efficiencies of CZTSSe-based solar cells, it is necessary to understand the fundamental factors that affect crystal growth and microstructure evolution during CZTSSe annealing. Cu2ZnSnS4 (CZTS) nanocrystals were synthesized via thermolysis of single-source cation and sulfur precursors copper, zinc and tin diethyldithiocarbamates. The average nanocrystal size could be tuned between 2 nm and 40 nm, by varying the synthesis temperature between 150 °C and 340 °C. The synthesis is rapid and is completed in less than 10 minutes. Characterization by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy confirm that the nanocrystals are nominally

  8. Microbial Ecology Assessment of Mixed Copper Oxide/Sulfide Dump Leach Operation

    SciTech Connect

    Bruhn, Debby Fox; Thompson, David Neal; Noah, Karl Scott

    1999-06-01

    Microbial consortia composed of complex mixtures of autotrophic and heterotrophic bacteria are responsible for the dissolution of metals from sulfide minerals. Thus, an efficient copper bioleaching operation depends on the microbial ecology of the system. A microbial ecology study of a mixed oxide/sulfide copper leaching operation was conducted using an "overlay" plating technique to differentiate and identify various bacterial consortium members of the genera Thiobacillus, “Leptospirillum”, “Ferromicrobium”, and Acidiphilium. Two temperatures (30°C and 45°C) were used to select for mesophilic and moderately thermophilic bacteria. Cell numbers varied from 0-106 cells/g dry ore, depending on the sample location and depth. After acid curing for oxide leaching, no viable bacteria were recovered, although inoculation of cells from raffinate re-established a microbial population after three months. Due to low the pH of the operation, very few non-iron-oxidizing acidophilic heterotrophs were recovered. Moderate thermophiles were isolated from the ore samples. Pregnant liquor solutions (PLS) and raffinate both contained a diversity of bacteria. In addition, an intermittently applied waste stream that contained high levels of arsenic and fluoride was tested for toxicity. Twenty vol% waste stream in PLS killed 100% of the cells in 48 hours, indicating substantial toxicity and/or growth inhibition. The data indicate that bacteria populations can recover after acid curing, and that application of the waste stream to the dump should be avoided. Monitoring the microbial ecology of the leaching operation provided significant information that improved copper recovery.

  9. Hydrothermal processes in partially serpentinized peridotites from Costa Rica: evidence from native copper and complex sulfide assemblages

    NASA Astrophysics Data System (ADS)

    Schwarzenbach, Esther M.; Gazel, Esteban; Caddick, Mark J.

    2014-11-01

    Native metals and metal alloys are common in serpentinized ultramafic rocks, generally representing the redox and sulfur conditions during serpentinization. Variably serpentinized peridotites from the Santa Elena Ophiolite in Costa Rica contain an unusual assemblage of Cu-bearing sulfides and native copper. The opaque mineral assemblage consists of pentlandite, magnetite, awaruite, pyrrhotite, heazlewoodite, violarite, smythite and copper-bearing sulfides (Cu-pentlandite, sugakiite [Cu(Fe,Ni)8S8], samaniite [Cu2(Fe,Ni)7S8], chalcopyrite, chalcocite, bornite and cubanite), native copper and copper-iron-nickel alloys. Using detailed mineralogical examination, electron microprobe analyses, bulk rock major and trace element geochemistry, and thermodynamic calculations, we discuss two models to explain the formation of the Cu-bearing mineral assemblages: (1) they formed through desulfurization of primary sulfides due to highly reducing and sulfur-depleted conditions during serpentinization or (2) they formed through interaction with a Cu-bearing, higher temperature fluid (350-400 °C) postdating serpentinization, similar to processes in active high-temperature peridotite-hosted hydrothermal systems such as Rainbow and Logatchev. As mass balance calculations cannot entirely explain the extent of the native copper by desulfurization of primary sulfides, we propose that the native copper and Cu sulfides formed by local addition of a hydrothermal fluid that likely interacted with adjacent mafic sequences. We suggest that the peridotites today exposed on Santa Elena preserve the lower section of an ancient hydrothermal system, where conditions were highly reducing and water-rock ratios very low. Thus, the preserved mineral textures and assemblages give a unique insight into hydrothermal processes occurring at depth in peridotite-hosted hydrothermal systems.

  10. A mild and facile synthesis of aryl and alkenyl sulfides via copper-catalyzed deborylthiolation of organoborons with thiosulfonates.

    PubMed

    Yoshida, Suguru; Sugimura, Yasuyuki; Hazama, Yuki; Nishiyama, Yoshitake; Yano, Takahisa; Shimizu, Shigeomi; Hosoya, Takamitsu

    2015-12-01

    An efficient deborylthiolation of aryl- and alkenylborons with thiosulfonates has been achieved under mild conditions using a copper catalyst. All steps of the experimental process were free from unpleasant odors. The mild reaction conditions as well as ready availability of boron compounds and thiosulfonates enabled easy access to an array of sulfides, including those bearing sensitive functional groups. PMID:26447905

  11. Synthesis of unsymmetrical sulfides using ethyl potassium xanthogenate and recyclable copper catalyst under ligand-free conditions.

    PubMed

    Akkilagunta, Vijay Kumar; Kakulapati, Rama Rao

    2011-08-19

    The synthesis of unsymmetrical sulfides has been achieved in good to excellent yields with inexpensive ethyl potassium xanthogenate via cross-coupling reaction using recyclable CuO nanoparticles under ligand-free conditions.The copper oxide nanoparticles can be recovered and reused up to five cycles without loss of activity. PMID:21732640

  12. Synthesis, Deposition, and Microstructure Development of Thin Films Formed by Sulfidation and Selenization of Copper Zinc Tin Sulfide Nanocrystals

    NASA Astrophysics Data System (ADS)

    Chernomordik, Boris David

    Significant reduction in greenhouse gas emission and pollution associated with the global power demand can be accomplished by supplying tens-of-terawatts of power with solar cell technologies. No one solar cell material currently on the market is poised to meet this challenge due to issues such as manufacturing cost, material shortage, or material toxicity. For this reason, there is increasing interest in efficient light-absorbing materials that are comprised of abundant and non-toxic elements for thin film solar cell. Among these materials are copper zinc tin sulfide (Cu2ZnSnS4, or CZTS), copper zinc tin selenide (Cu2ZnSnSe4, or CZTSe), and copper zinc tin sulfoselenide alloys [Cu2ZnSn(SxSe1-x )4, or CZTSSe]. Laboratory power conversion efficiencies of CZTSSe-based solar cells have risen to almost 13% in less than three decades of research. Meeting the terawatt challenge will also require low cost fabrication. CZTSSe thin films from annealed colloidal nanocrystal coatings is an example of solution-based methods that can reduce manufacturing costs through advantages such as high throughput, high material utilization, and low capital expenses. The film microstructure and grain size affects the solar cell performance. To realize low cost commercial production and high efficiencies of CZTSSe-based solar cells, it is necessary to understand the fundamental factors that affect crystal growth and microstructure evolution during CZTSSe annealing. Cu2ZnSnS4 (CZTS) nanocrystals were synthesized via thermolysis of single-source cation and sulfur precursors copper, zinc and tin diethyldithiocarbamates. The average nanocrystal size could be tuned between 2 nm and 40 nm, by varying the synthesis temperature between 150 °C and 340 °C. The synthesis is rapid and is completed in less than 10 minutes. Characterization by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy confirm that the nanocrystals are nominally

  13. Determination of (210)Po in drinking water and urine samples using copper sulfide microprecipitation.

    PubMed

    Guérin, Nicolas; Dai, Xiongxin

    2014-06-17

    Polonium-210 ((210)Po) can be rapidly determined in drinking water and urine samples by alpha spectrometry using copper sulfide (CuS) microprecipitation. For drinking water, Po in 10 mL samples was directly coprecipitated onto the filter for alpha counting without any purification. For urine, 10 mL of sample was heated, oxidized with KBrO3 for a short time (∼5 min), and subsequently centrifuged to remove the suspended organic matter. The CuS microprecipitation was then applied to the supernatant. Large batches of samples can be prepared using this technique with high recoveries (∼85%). The figures of merit of the methods were determined, and the developed methods fulfill the requirements for emergency and routine radioassays. The efficiency and reliability of the procedures were confirmed using spiked samples. PMID:24906041

  14. Water soluble sodium sulfate nanorods as a versatile template for the designing of copper sulfide nanotubes.

    PubMed

    Das, Gautam; Kakati, Nitul; Lee, Seok Hee; Karak, Niranjan; Yoon, Young Soo

    2014-06-01

    The present study reports the use of water soluble sodium sulfate (Na2SO4) nanorods as a versatile template for generation of tubular copper sulfide (CuS) nanostructures. The Na2SO4 nanorods were synthesized from ammonium sulfate (NH4)2SO4 and sodium hydroxide (NaOH), under refluxing condition. The shape and morphology control of the Na2SO4 nanorods were studied with respect to nature of surfactant used and reactant mole ratio. While, PVP mole ratio was important to obtain homogeneous nanorods. Uniform and stable nanotubes of CuS were than obtained by the dissolution of the nanorods in water. The use of simple chemicals for synthesis of such nanotube templates opens the prospect for wide scale downstream applications. PMID:24738412

  15. Optical and thermal response of single-walled carbon nanotube-copper sulfide nanoparticle hybrid nanomaterials.

    PubMed

    Tseng, Yi-Hsuan; He, Yuan; Lakshmanan, Santana; Yang, Chang; Chen, Wei; Que, Long

    2012-11-16

    This paper reports the optical and thermal response of a single-walled carbon nanotube-copper sulfide nanoparticle (SWNT-CuS NP) hybrid nanomaterial and its application as a thermoelectric generator. The hybrid nanomaterial was synthesized using oleylamine molecules as the linker molecules between SWNTs and CuS NPs. Measurements found that the hybrid nanomaterial has significantly increased light absorption (up to 80%) compared to the pure SWNT. Measurements also found that the hybrid nanomaterial thin-film devices exhibit a clear optical and thermal switching effect, which can be further enhanced up to 10 ×  by asymmetric illumination of light and thermal radiation on the thin-film devices instead of symmetric illumination. A simple prototype thermoelectric generator enabled by the hybrid nanomaterials is demonstrated, indicating a new route for achieving thermoelectricity. PMID:23089651

  16. Synthesis of Copper-Antimony-Sulfide Nanocrystals for Solution-Processed Solar Cells.

    PubMed

    Suehiro, Satoshi; Horita, Keisuke; Yuasa, Masayoshi; Tanaka, Tooru; Fujita, Katsuhiko; Ishiwata, Yoichi; Shimanoe, Kengo; Kida, Tetsuya

    2015-08-17

    The p-type nanocrystals (NCs) of copper-based chalcogenides, such as CuInSe2 and Cu2ZnSnS4, have attracted increasing attention in photovoltaic applications due to their potential to produce cheap solution-processed solar cells. Herein, we report the synthesis of copper-antimony-sulfide (CAS) NCs with different crystal phases including CuSbS2, Cu3SbS4, and Cu12Sb4S13. In addition, their morphology, crystal phase, and optical properties were characterized using transmission electron microscopy, X-ray diffractometry, UV-vis-near-IR spectroscopy, and photoemission yield spectroscopy. The morphology, crystal phase, and electronic structure were significantly dependent on the chemical composition in the CAS system. Devices were fabricated using particulate films consisting of CAS NCs prepared by spin coating without a high-temperature treatment. The CAS NC-based devices exhibited a diode-like current-voltage characteristic when coupled with an n-type CdS layer. In particular, the CuSbS2 NC devices exhibited photovoltaic responses under simulated sunlight, demonstrating its applicability for use in solution-processed solar cells. PMID:26237216

  17. Nickel-cobalt-iron-copper sulfides and arsenides in solution-collapse breccia pipes, northwestern Arizona

    SciTech Connect

    Wenrich, K.J. ); Hlava, P.F. )

    1993-04-01

    An extensive suite of Ni-Co-Fe-Cu sulfides and arsenides lies within the matrix of solution-collapse breccias buried deep within the plateaus of the Grand Canyon region. Ceilings over large caverns in the Redwall collapsed, brecciating the overlying sandstone and forming cylindrical breccia pipes up to 300 ft in diameter that extend vertically as much as 3,000 ft. These highly permeable breccias served as a host for the precipitation of a suite of over 100 minerals, including uraninite, sphalerite, galena and various copper phases, in addition to the Ni-Co-bearing-phase discussed here. Intricately zoned crystals of small (<1 mm), euhedral Ni-Co-Fe-As-S minerals were the first to form during the second major episode of mineralization in these pipes. Several of these phases replace minerals, such as barite and anhydrite, from the first episode. Extensive microprobe work has been done on samples from two breccia pipe mines, the Hack 2 and Orphan, which are about 50 miles apart. Mineral compositions are similar except that no copper is found in the Ni-Co-Fe phases from the Hack 2 mine, while pyrites containing 1 wt % Cu are common from the Orphan, which was mined for copper. In some of these pyrites', Cu is dominant and the mineral is actually villamaninite. Pyrites from both mines characteristically contain 0.5 to 3 wt % As. Metal contents in zones pyrite-bravoite-vaesite (M[sub 1]S[sub 2]) crystals at the Hack 2 mine range from Fe[sub 1] to Fe[sub .12], Ni[sub 0] to Ni[sub .86], and Co[sub 0] to Co[sub .10]. The metal content for polydymite-siegenite-violarite averages about (Ni[sub 2.33]Co[sub .39]Fe[sub .23])(S[sub 3.9]As[sub .1]). Orphan mine pyrite-bravoite-vaesite-villamaninite ranges in composition from pure FeS[sub 2] to (Ni[sub .6]Fe[sub .21]Co[sub .17])S[sub 2], and (Cu[sub .46]Ni[sub .27]Fe[sub .21]Co[sub .13])S[sub 2]. Of all the sulfides or arsenides found in these breccia pipes, only nickeline consistently occurs as the pure end member.

  18. Structural, chemical and optical properties of the polyethylene-copper sulfide composite thin films synthesized using polythionic acid as sulfur source

    NASA Astrophysics Data System (ADS)

    Ancutiene, Ingrida; Navea, Juan G.; Baltrusaitis, Jonas

    2015-08-01

    Synthesis and properties of thin copper sulfide films deposited on polyethylene were explored for the development of low cost hybrid organic-inorganic photovoltaic materials. Polyethylene was used as a model organic host material for thin copper sulfide film formation. Adsorption-diffusion method was used which utilized consecutive exposure of polyethylene to polythionic acid followed by aqueous Cu(II/I) solution. Several crystalline copper sulfide phases were obtained in synthesized samples and elucidated using X-ray diffraction. Surface chemical composition determined using X-ray photoelectron spectroscopy showed the presence of copper sulfides in combination with copper hydroxide. Thickness of the composite material films ranged from several microns to ∼18 μm and depended on the Cu(II/I) exposure time. Bandgap of the materials obtained was measured and ranged from 1.88 to 1.17 eV. Importantly, heating these complex copper sulfide crystalline phase containing films at 100 °C in inert atmosphere invariably resulted in a single copper sulfide, anilite (Cu1.75S), phase. Anilite possesses a bandgap of 1.36 eV and has demonstrated excellent photovoltaic properties. Thus, the method described in this work can be used for a low cost large scale composite thin film photovoltaic material deposition based on anilite as photoactive material.

  19. Nanocrystalline copper sulfide of varying morphologies and stoichiometries in a low temperature solvothermal process using a new single-source molecular precursor

    NASA Astrophysics Data System (ADS)

    Bera, Pulakesh; Seok, Sang Il

    2012-08-01

    Surfactantless synthesis of copper sulfide nanoparticles (NPs) with varied morphologies such as hexagonal rods, rhombohedral, and spherical, has been carried out via low-temperature thermolysis of a new single-source precursor, [Cu(SMDTC)Cl2], (where SMDTC is S-methyl dithiocarbazate). The reaction parameters e.g., temperature and nature of solvent can be used to control the size and morphology of the nanoparticles. It is observed that the solvents played an important role to control the morphology and stoichiometry of copper sulfide. The anisotropic absorption by the chelating solvent (diamine or ethyleneglycol) at the different facets of the newborn microcrystals results the growth of one-dimensional (1D) copper sulfide NPs. The possible formation mechanism of copper sulfide NPs has also been discussed.

  20. Manganese (II) Chelate Functionalized Copper Sulfide Nanoparticles for Efficient Magnetic Resonance/Photoacoustic Dual-Modal Imaging Guided Photothermal Therapy

    PubMed Central

    Liu, Renfa; Jing, Lijia; Peng, Dong; Li, Yong; Tian, Jie; Dai, Zhifei

    2015-01-01

    The integration of diagnostic and therapeutic functionalities into one nanoplatform shows great promise in cancer therapy. In this research, manganese (II) chelate functionalized copper sulfide nanoparticles were successfully prepared using a facile hydrothermal method. The obtained ultrasmall nanoparticles exhibit excellent photothermal effect and photoaoustic activity. Besides, the high loading content of Mn(II) chelates makes the nanoparticles attractive T1 contrast agent in magnetic resonance imaging (MRI). In vivo photoacoustic imaging (PAI) results showed that the nanoparticles could be efficiently accumulated in tumor site in 24 h after systematic administration, which was further validated by MRI tests. The subsequent photothermal therapy of cancer in vivo was achieved without inducing any observed side effects. Therefore, the copper sulfide nanoparticles functionalized with Mn(II) chelate hold great promise as a theranostic nanomedicine for MR/PA dual-modal imaging guided photothermal therapy of cancer. PMID:26284144

  1. Synthesis and Biomedical Applications of Copper Sulfide Nanoparticles: From Sensors to Theranostics

    PubMed Central

    Goel, Shreya; Chen, Feng; Cai, Weibo

    2013-01-01

    Copper sulfide (CuS) nanoparticles have attracted increasing attention from biomedical researchers across the globe, because of their intriguing properties which have been mainly explored for energy- and catalysis-related applications to date. This focused review article aims to summarize the recent progress made in the synthesis and biomedical applications of various CuS nanoparticles. After a brief introduction to CuS nanoparticles in the first section, we will provide a concise outline of the various synthetic routes to obtain different morphologies of CuS nanoparticles, which can influence their properties and potential applications. CuS nanoparticles have found broad applications in vitro, especially in the detection of biomolecules, chemicals, and pathogens which will be illustrated in detail. The in vivo uses of CuS nanoparticles have also been investigated in preclinical studies, including molecular imaging with various techniques, cancer therapy based on the photothermal properties of CuS, as well as drug delivery and theranostic applications. Research on CuS nanoparticles will continue to thrive over the next decade, and tremendous opportunities lie ahead for potential biomedical/clinical applications of CuS nanoparticles. PMID:24106015

  2. Using Plasmonic Copper Sulfide Nanocrystals as Smart Light-Driven Sterilants.

    PubMed

    Liu, Zhen; Liu, Xianjun; Du, Yingda; Ren, Jinsong; Qu, Xiaogang

    2015-10-27

    As an efficient route to control pet overpopulation and develop neutered experimental animals, male sterilization via surgical techniques, chemical injections, and antifertility vaccines has brought particular attention recently. However, these traditional ways usually induce long-term adverse reactions, immune suppression, and serious infection and pain. To overcome the above limitations, we developed a platform in the present study by using plasmonic copper sulfide nanocrystals (Cu2-xS NCs) as intelligent light-driven sterilants with ideal outcomes. Upon NIR laser irradiation, these well-prepared Cu2-xS NCs can possess NIR-induced hyperthermia and generate high levels of reactive oxygen species (ROS). Due to the cooperation of photothermal and photodynamic effects, these nanocrystals exhibited NIR-mediated toxicity toward Sertoli cells both in vitro and in vivo in a mild manner. We attribute the potential mechanism of cellular injury to the apoptosis-related death and denaturation of protein in the testicles. Furthermore, the possible metabolism route and long-term toxicity of these nanocrystals after testicular injection indicate their high biocompatibility. Taking together, our study on the NIR-induced toxicity of Cu2-xS NCs provides keen insights for the usage of plasmonic nanomaterials in biomedicine. PMID:26331394

  3. Bioleaching model of a copper-sulfide ore bed in heap and dump configurations

    NASA Astrophysics Data System (ADS)

    Casas, J. M.; Vargas, T.; Martinez, J.; Moreno, L.

    1998-08-01

    A two-dimensional (2-D) model for a heap or dump bioleaching of a copper ore containing mainly chalcocite and pyrite has been developed. The rate of the mineral sulfide dissolution was related to the rate of oxidation by bacteria attached onto the ore surface. The latter was calculated using the model of Michaelis-Menten, where both temperature and dissolved oxygen in the leach solution were taken into account by the kinetic equation. Oxygen transport through the ore bed was associated with natural air convection originating from the decrease in gas density inside the ore bed, which was attributable not only to heating, but also to humidification and decrease in the oxygen concentration. The model was used to estimate air-velocity fields and profiles of temperature and oxygen concentrations as well as mineral conversions during the bioleaching operation for ore beds with different pyrite contents, bacterial populations, widths, heights, and permeabilities. The model provides a useful tool for the design, improvement, and optimization of industrial operating conditions.

  4. Seasonal distribution of organic matter and copper under stratified conditions in a karstic, marine, sulfide rich environment (Rogoznica Lake, Croatia)

    NASA Astrophysics Data System (ADS)

    Plavšić, Marta; Ciglenečki, Irena; Strmečki, Slađana; Bura-Nakić, Elvira

    2011-04-01

    Closed, isolated small systems, as the representatives of a "unique-environmental feature", are valuable natural laboratories for studying different biogeochemical processes. The saline Rogoznica Lake ("Dragon Eye"), situated on the Eastern Adriatic coast is such a system (10 276 m 2, 15 m deep) typical of many stratified, sulfide rich water bodies. The depth of mixolimnion changes seasonally and it is greatly influenced by meteorological conditions, i.e. temperature and rainfall. Vertical mixing usually occurs during winter when cold, oxygen-rich water from the surface sinks downwards. In 2009 we monitored seasonal distribution and variation of copper complexing capacity (L T), related apparent stability constants (K app), concentration of Cu 2+ ions, surfactant activity (SAS), dissolved organic carbon (DOC) and reduced sulfur species (RSS). Our results have shown that L T is increasing with depth up to 8 m depth, while the concentrations of copper ions decrease with the depth due to the higher amount of RSS species in deeper layers. The values of log K app are also decreasing with depth as a consequence of a competition of organic ligands and sulfide ions for binding Cu. Below 8 m depth the presence of high amounts of RSS (˜1 mM) influences the electrochemical measuring of copper ion and L T determination, contributing to the copper ion binding.

  5. Tin Ion Directed Morphology Evolution of Copper Sulfide Nanoparticles and Tuning of Their Plasmonic Properties via Phase Conversion.

    PubMed

    Chen, Lihui; Sakamoto, Masanori; Haruta, Mitsutaka; Nemoto, Takashi; Sato, Ryota; Kurata, Hiroki; Teranishi, Toshiharu

    2016-08-01

    Copper-deficient copper sulfide (Cu2-xS) nanoparticles (NPs) have been investigated as important hole-based plasmonic materials because of their size, morphology, and carrier density-dependent localized surface plasmon resonance (LSPR) properties. Morphology and carrier density are two important parameters to determine their LSPR properties. Here, we demonstrate that the foreign metal ion, Sn(4+), directs the growth of djurleite Cu31S16 from nanodisk to tetradecahedron along the [100] direction. To control the LSPR properties by tuning the carrier density, the djurleite Cu31S16 nanoparticles were pseudomorphically converted into more copper-deficient (higher carrier density) roxbyite Cu7S4 NPs by heat treatment in the presence of amine. The roxbyite Cu7S4 NPs exhibited a shorter and stronger LSPR peak while retaining the morphology of the djurleite Cu31S16 NPs. PMID:27398864

  6. Synthesis of Mesostructured Copper Sulfide by Cation Exchange and Liquid Crystal Templating

    SciTech Connect

    Lubeck, C R; Doyle, F M; Gash, A E; Satcher, J H; Han, T Y

    2005-08-01

    describe for the first time, the successful synthesis of highly ordered, mesostructured Cu{sub x}S, by combining the templating of the supramolecular assemblies of non-ionic amphiphilic polymer method with the cation exchange method to transform mesostructured cadmium sulfide (CdS) into mesostructured copper sulfides (CuS, Cu{sub 2}S).

  7. Reaction Mechanisms of Metals with Hydrogen Sulfide and Thiols in Model Wine. Part 1: Copper-Catalyzed Oxidation.

    PubMed

    Kreitman, Gal Y; Danilewicz, John C; Jeffery, David W; Elias, Ryan J

    2016-05-25

    Sulfidic off-odors as a result of hydrogen sulfide (H2S) and low-molecular-weight thiols are commonly encountered in wine production. These odors are usually removed by the process of Cu(II) fining, a process that remains poorly understood. The present study aims to elucidate the underlying mechanisms by which Cu(II) interacts with H2S and thiol compounds (RSH) under wine-like conditions. Copper complex formation was monitored along with H2S, thiol, oxygen, and acetaldehyde concentrations after the addition of Cu(II) (50 or 100 μM) to air-saturated model wine solutions containing H2S, cysteine, 6-sulfanylhexan-1-ol, or 3-sulfanylhexan-1-ol (300 μM each). The presence of H2S and thiols in excess to Cu(II) led to the rapid formation of ∼1.4:1 H2S/Cu and ∼2:1 thiol/Cu complexes, resulting in the oxidation of H2S and thiols and reduction of Cu(II) to Cu(I), which reacted with oxygen. H2S was observed to initially oxidize rather than form insoluble copper sulfide. The proposed reaction mechanisms provide insight into the extent to which H2S can be selectively removed in the presence of thiols in wine. PMID:27133282

  8. Formation of Hydrogen Sulfide in Wine: Interactions between Copper and Sulfur Dioxide.

    PubMed

    Bekker, Marlize Z; Smith, Mark E; Smith, Paul A; Wilkes, Eric N

    2016-01-01

    The combined synergistic effects of copper (Cu(2+)) and sulfur dioxide (SO₂) on the formation of hydrogen sulfide (H₂S) in Verdelho and Shiraz wine samples post-bottling was studied over a 12-month period. The combined treatment of Cu(2+) and SO₂ significantly increased H₂S formation in Verdelho wines samples that were not previously treated with either Cu(2+) or SO₂. The formation of H₂S produced through Cu(2+) mediated reactions was likely either: (a) directly through the interaction of SO₂ with either Cu(2+) or H₂S; or (b) indirectly through the interaction of SO₂ with other wine matrix compounds. To gain better understanding of the mechanisms responsible for the significant increases in H₂S concentration in the Verdelho samples, the interaction between Cu(2+) and SO₂ was studied in a model wine matrix with and without the presence of a representative thiol quenching compound (4-methylbenzoquinone, 4MBQ). In these model studies, the importance of naturally occurring wine compounds and wine additives, such as quinones, SO₂, and metal ions, in modulating the formation of H₂S post-bottling was demonstrated. When present in equimolar concentrations a 1:1 ratio of H₂S- and SO₂-catechol adducts were produced. At wine relevant concentrations, however, only SO₂-adducts were produced, reinforcing that the competition reactions of sulfur nucleophiles, such as H₂S and SO₂, with wine matrix compounds play a critical role in modulating final H₂S concentrations in wines. PMID:27626394

  9. Enhanced reactive adsorption of hydrogen sulfide on the composites of graphene/graphite oxide with copper (hydr)oxychlorides.

    PubMed

    Mabayoje, Oluwaniyi; Seredych, Mykola; Bandosz, Teresa J

    2012-06-27

    Composites of copper (hydr)oxychlorides with graphite oxide or graphene were synthesized and used as adsorbents of hydrogen sulfide at dynamic conditions at ambient temperatures. The materials were extensively characterized before and after adsorption in order to link their performance to the surface features. X-ray diffraction, FTIR, thermal analysis, TEM, SEM/EDX, and adsorption of nitrogen were used. It was found that the composite with graphene has the most favorable surface features enhancing reactive adsorption of hydrogen sulfide. The presence of moisture in the H2S stream has a positive effect on the removal process owing to the dissociation process. H2S is retained on the surface via a direct replacement of OH groups and via acid-base reactions with the copper (hydr)oxide. Highly dispersed reduced copper species on the surface of the composite with graphene enhance activation of oxygen and cause formation of sulfites and sulfates. Higher conductivity of the graphene phase than that of graphite oxide helps in electron transfer in redox reactions. PMID:22667349

  10. Growth evolution and phase transition from chalcocite to digenite in nanocrystalline copper sulfide: Morphological, optical and electrical properties

    PubMed Central

    Quintana-Ramirez, Priscilla Vasthi; Santos-Cruz, José; Vega-González, Marina; Martínez-Alvarez, Omar; Castaño-Meneses, Víctor Manuel; Acosta-Torres, Laura Susana; de la Fuente-Hernández, Javier

    2014-01-01

    Summary Copper sulfide is a promising p-type inorganic semiconductor for optoelectronic devices such as solar cells, due its small band gap energy and its electrical properties. In this work nanocrystalline copper sulfide (CuxS), with two stoichiometric ratios (x = 2, 1.8) was obtained by one-pot synthesis at 220, 230, 240 and 260 °C in an organic solvent and amorphous CuxS was obtained in aqueous solution. Nanoparticle-like nucleation centers are formed at lower temperatures (220 °C), mixtures of morphologies (nanorods, nanodisks and nanoprisms) are seen at 230 and 240 °C, in which the nanodisks are predominant, while big hexagonal/prismatic crystals are obtained at 260 °C according to TEM results. A mixture of chalcocite and digenite phases was found at 230 and 240 °C, while a clear transition to a pure digenite phase was seen at 260 °C. The evolution of morphology and transition of phases is consistent to the electrical, optical, and morphological properties of the copper sulfide. In fact, digenite Cu1.8S is less resistive (346 Ω/sq) and has a lower energy band gap (1.6 eV) than chalcocite Cu2S (5.72 × 105 Ω/sq, 1.87 eV). Low resistivity was also obtained in CuxS synthesized in aqueous solution, despite its amorphous structure. All CuxS products could be promising for optoelectronic applications. PMID:25247136

  11. Growth evolution and phase transition from chalcocite to digenite in nanocrystalline copper sulfide: Morphological, optical and electrical properties.

    PubMed

    Quintana-Ramirez, Priscilla Vasthi; Arenas-Arrocena, Ma Concepción; Santos-Cruz, José; Vega-González, Marina; Martínez-Alvarez, Omar; Castaño-Meneses, Víctor Manuel; Acosta-Torres, Laura Susana; de la Fuente-Hernández, Javier

    2014-01-01

    Copper sulfide is a promising p-type inorganic semiconductor for optoelectronic devices such as solar cells, due its small band gap energy and its electrical properties. In this work nanocrystalline copper sulfide (Cu x S), with two stoichiometric ratios (x = 2, 1.8) was obtained by one-pot synthesis at 220, 230, 240 and 260 °C in an organic solvent and amorphous Cu x S was obtained in aqueous solution. Nanoparticle-like nucleation centers are formed at lower temperatures (220 °C), mixtures of morphologies (nanorods, nanodisks and nanoprisms) are seen at 230 and 240 °C, in which the nanodisks are predominant, while big hexagonal/prismatic crystals are obtained at 260 °C according to TEM results. A mixture of chalcocite and digenite phases was found at 230 and 240 °C, while a clear transition to a pure digenite phase was seen at 260 °C. The evolution of morphology and transition of phases is consistent to the electrical, optical, and morphological properties of the copper sulfide. In fact, digenite Cu1.8S is less resistive (346 Ω/sq) and has a lower energy band gap (1.6 eV) than chalcocite Cu2S (5.72 × 10(5) Ω/sq, 1.87 eV). Low resistivity was also obtained in Cu x S synthesized in aqueous solution, despite its amorphous structure. All Cu x S products could be promising for optoelectronic applications. PMID:25247136

  12. Copper Sulfide Nanoparticles as a New Class of Photoacoustic Contrast Agent for Deep Tissue Imaging at 1064-nm

    PubMed Central

    Ku, Geng; Zhou, Min; Song, Shaoli; Huang, Qian; Hazle, John; Li, Chun

    2012-01-01

    Photoacoustic tomography (PAT) is an emerging molecular imaging modality. Here, we demonstrate use of semiconductor copper sulfide nanoparticles (CuS NP) for PAT with an Nd:YAG laser at a wavelength of 1064 nm. CuS NP allowed visualization of mouse brain after intracranial injection, rat lymph nodes 12 mm below the skin after interstitial injection, and CuS NP-containing agarose gel embedded in chicken breast muscle at the depth of ~ 5 cm. This imaging approach has great potential for molecular imaging of breast cancer. PMID:22812694

  13. Efficient Synthesis of Highly Luminescent Copper Indium Sulfide-Based Core/Shell Nanocrystals with Surprisingly Long-Lived Emission

    SciTech Connect

    Li, Liang; Pandey, Anshu; Werder, Donald J.; Khanal, Bishnu P.; Pietryga, Jeffrey M.; Klimov, Victor I.

    2011-02-09

    We report an efficient synthesis of copper indium sulfide nanocrystals with strong photoluminescence in the visible to near-infrared. This method can produce gram quantities of material with a chemical yield in excess of 90% with minimal solvent waste. The overgrowth of as-prepared nanocrystals with a few monolayers of CdS or ZnS increases the photoluminescence quantum efficiency to > 80%. On the basis of time-resolved spectroscopic studies of core/shell particles, we conclude that the emission is due to an optical transition that couples a quantized electron state to a localized hole state, which is most likely associated with an internal defect.

  14. Utilising copper screen-printed electrodes (CuSPE) for the electroanalytical sensing of sulfide.

    PubMed

    Thakur, Bhawana; Bernalte, Elena; Smith, Jamie P; Foster, Christopher W; Linton, Patricia E; Sawant, Shilpa N; Banks, Craig E

    2016-02-21

    A mediatorless sulfide electrochemical sensing platform utilising a novel nanocopper-oxide screen-printed electrodes (CuSPE) is reported for the first time. The state-of-the-art screen-printed electrochemical sensors demonstrate their capability to quantify sulfide within both the presence and absence of an array of interferents with good levels of sensitivity and repeatability. The direct sensing (using linear sweep voltammetry) of sulfide utilising the CuSPEs provides a mediatorless approach for the detection of sulfide, yielding useful analytical signatures that can be successfully quantified. The proposed novel protocol using the CuSPEs is successfully applied to the sensing of sulfide within drinking water exhibiting a high level of recovery. PMID:26815001

  15. Three approaches to economical photovoltaics: Conformal copper sulfide , organic luminescent films, and lead selenide nanocrystal superlattices

    NASA Astrophysics Data System (ADS)

    Carbone, Ian A.

    Three routes to more efficient photovoltaics using conformal Cu2S, organic luminescent films, and nanocrystalline PbSe films are outlined below. Properties of these materials are investigated experimentally and numerically in separate studies. In the first study, chemical vapor deposition (CVD) processes were used to fabricate Cu2S using hydrogen sulfide and the metal-organic precursor, KI5. The alternating exposure of mesoporous TiO2 and planar ZnO to the two precursors resulted in films that penetrated porous structures and deposited at a constant rate of 0.08nm/cycle over the temperature range 150C-400°C. Sheet resistance and optical absorption measurements suggest the presence of a metallic copper-poor phase of less than 100nm thick forming at the Cu2S/substrate boundary. In a separate study, organic films doped with luminescent dyes were placed above CdTe/CdS solar cells to convert high energy photons to lower energies, better matched to the CdTe/CdS quantum efficiency peak. Efficiency improvements of up to 8.5% were obtained after optimizing dye concentration, dye chemistry, and the host material. Long-term stability tests show that the organic films are stable for at least 5000 hours under 1 sun illumination provided that the dye is encapsulated in an oxygen and water free environment. Finally, a Monte Carlo model was developed to simulate electron and hole transport in nanocrystalline PbSe films. Transport is carried out as a series of thermally activated tunneling events between neighboring sites on a cubic lattice. Each site, representing an individual nanocrystal, is assigned a size-dependent electronic structure, and the effects of crystal size, charging, inter-crystal coupling, and energetic disorder on electron and hole mobilities/conductivities are investigated. Results of simulated field effect measurements confirm that electron mobilities and conductivities increase by an order of magnitude when the average nanocrystal diameter is increased in the

  16. Cadmium sulfide-copper sulfide heterojunction cell research. Quarterly progress report, December 1, 1979-February 29, 1980

    SciTech Connect

    1980-07-01

    Attempts have been continued to increase the short circuit current in cells of enhanced open circuit voltage. Both deposition of copper on the surface of the Cu/sub 2/S layer and hydrogen plasma treatments have been attempted. To date, no significant increase in ultimate current has been achieved. Various changes in cell production procedure have been made with significant improvements in reproducibility. Improvements in the structure of (CdZn)S layers and resulting cell properties have been achieved using modified substrates based on NiFe. Improvement have been made to the capacitance measuring systems with a consequent gain in resolution, accuracy and reproducibility. Structural studies of the electron beam deposited glass have revealed the presence of cracking and experiments have been carried out to determine the optimum deposition conditions for producing defect-free coatings.

  17. Weathering of sulfidic shale and copper mine waste: Secondary minerals and metal cycling in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA

    USGS Publications Warehouse

    Hammarstrom, J.M.; Seal, R.R., II; Meier, A.L.; Jackson, J.C.

    2003-01-01

    Metal cycling via physical and chemical weathering of discrete sources (copper mines) and regional (non-point) sources (sulfide-rich shale) is evaluated by examining the mineralogy and chemistry of weathering products in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA. The elements in copper mine waste, secondary minerals, stream sediments, and waters that are most likely to have negative impacts on aquatic ecosystems are aluminum, copper, zinc, and arsenic because these elements locally exceed toxicity guidelines for surface waters or for stream sediments. Acid-mine drainage has not developed in streams draining inactive copper mines. Acid-rock drainage and chemical weathering processes that accompany debris flows or human disturbances of sulfidic rocks are comparable to processes that develop acid-mine drainage elsewhere. Despite the high rainfall in the mountain range, sheltered areas and intermittent dry spells provide local venues for development of secondary weathering products that can impact aquatic ecosystems.

  18. Highly selective and sensitive colorimetric probe for hydrogen sulfide by a copper (II) complex of azo-dye based on chemosensing ensemble approach

    NASA Astrophysics Data System (ADS)

    Zhang, Dengqing; Jin, Wusong

    2012-05-01

    A copper (II) complex of azo-dye (Cu-1) has been synthesized by the reaction of 1-(2-pyridylazo)-2-naphthol (1) with copper (II) chloride. The complex Cu-1 is able to selectively sense hydrogen sulfide over other anions followed by the release of compound 1 to give a remarkable change of UV-vis absorption at neutral pH in aqueous solution.

  19. Highly sensitive photodetectors based on hybrid 2D-0D SnS2-copper indium sulfide quantum dots

    NASA Astrophysics Data System (ADS)

    Huang, Yun; Zhan, Xueying; Xu, Kai; Yin, Lei; Cheng, Zhongzhou; Jiang, Chao; Wang, Zhenxing; He, Jun

    2016-01-01

    Both high speed and efficiency of photoelectric conversion are essential for photodetectors. As an emerging layered metal dichalcogenide (LMD), tin disulfide owns intrinsic faster photodetection ability than most other LMDs but poor light absorption and low photoelectric conversion efficiency. We develop an efficient method to enhance its performance by constructing a SnS2-copper indium sulfide hybrid structure. As a result, the responsivity reaches 630 A/W, six times stronger than pristine SnS2 and much higher than most other LMDs photodetectors. Additionally, the photocurrents are enhanced by more than 1 order of magnitude. Our work may open up a pathway to improve the performance of photodetectors based on LMDs.

  20. Size Dependence of a Temperature-Induced Solid-Solid Phase Transition in Copper(I) Sulfide

    SciTech Connect

    Rivest, Jessy B; Fong, Lam-Kiu; Jain, Prashant K; Toney, Michael F; Alivisatos, A Paul

    2011-07-24

    Determination of the phase diagrams for the nanocrystalline forms of materials is crucial for our understanding of nanostructures and the design of functional materials using nanoscale building blocks. The ability to study such transformations in nanomaterials with controlled shape offers further insight into transition mechanisms and the influence of particular facets. Here we present an investigation of the size-dependent, temperature-induced solid-solid phase transition in copper sulfide nanorods from low- to high-chalcocite. We find the transition temperature to be substantially reduced, with the high chalcocite phase appearing in the smallest nanocrystals at temperatures so low that they are typical of photovoltaic operation. Size dependence in phase trans- formations suggests the possibility of accessing morphologies that are not found in bulk solids at ambient conditions. These other- wise-inaccessible crystal phases could enable higher-performing materials in a range of applications, including sensing, switching, lighting, and photovoltaics.

  1. Copper sulfide nanoparticle-decorated graphene as a catalytic amplification platform for electrochemical detection of alkaline phosphatase activity.

    PubMed

    Peng, Juan; Han, Xiao-Xia; Zhang, Qing-Chun; Yao, Hui-Qin; Gao, Zuo-Ning

    2015-06-01

    Copper sulfide nanoparticle-decorated graphene sheet (CuS/GR) was successfully synthesized and used as a signal amplification platform for electrochemical detection of alkaline phosphatase activity. First, CuS/GR was prepared through a microwave-assisted hydrothermal approach. The CuS/GR nanocomposites exhibited excellent electrocatalytic activity toward the oxidation of ALP hydrolyzed products such as 1-naphthol, which produced a current response. Thus, a catalytic amplification platform based on CuS/GR nanocomposite for electrochemical detection of ALP activity was designed using 1-naphthyl phosphate as a model substrate. The current response increased linearly with ALP concentration from 0.1 to 100 U L(-1) with a detection limit of 0.02 U L(-1). The assay was applied to estimate ALP activity in human serum samples with satisfactory results. This strategy may find widespread and promising applications in other sensing systems that involves ALP. PMID:26002329

  2. Nanoparticles of zinc sulfide doped with manganese, nickel and copper as nanophotocatalyst in the degradation of organic dyes.

    PubMed

    Pouretedal, Hamid Reza; Norozi, Abbas; Keshavarz, Mohammad Hossein; Semnani, Abolfazl

    2009-03-15

    Nanoparticles of zinc sulfide as undoped and doped with manganese, nickel and copper were used as photocatalyst in the photodegradation of methylene blue and safranin as color pollutants. Photoreactivity of doped zinc sulfide was varied with dopant, mole fraction of dopant to zinc ion, pH of solution, dosage of photocatalyst and concentration of dye. The characterization of nanoparticles was studied using X-ray powder diffraction (XRD) patterns and UV-vis spectra. The maximum degradation efficiency was obtained in the presence of Zn(0.98)Mn(0.02)S, Zn(0.94)Ni(0.06)S and Zn(0.90)Cu(0.10)S as nanophotocatalyst. The effect of dosage of photocatalyst was studied in the range of 20-250 mg/L. It was seen that 150.0 mg/L of photocatacyst is an optimum value for the dosage of photocatalyst. The most degradation efficiency was obtained in alkaline pH of 11.0 with study of photodegradation in pH amplitude of 2-12. The degradation efficiency was decreased in dye concentrations above of 5.0 mg/L for methylene blue and safranin dyes. In the best conditions, the degradation efficiency was obtained 87.3-95.6 and 85.4-93.2 for methylene blue and safranin, respectively. PMID:18603365

  3. A green synthesis route for the phase and size tunability of copper antimony sulfide nanocrystals with high yield.

    PubMed

    Chen, Keqiang; Zhou, Jing; Chen, Wen; Chen, Qiao; Zhou, Peng; Liu, Yueli

    2016-03-01

    Until now, it is a great challenge for the controllable synthesis of copper antimony sulfide (CAS) nanocrystals (NCs), as the reactivity of precursors is quite difficult to be controlled during the synthesis process. In the present work, a novel solution-based method is proposed to synthesize CAS NCs by choosing N,N'-diphenylthiourea as the sulfide precursor, which is favorable for balancing the relative reactivity of Cu and Sb ions. It is found that three phases (CuSbS2, Cu12Sb4S13 and Cu3SbS4) of CAS NCs with size tunability were successfully synthesized for the first time. To the best of our knowledge, the lowest reaction temperature of 110 °C and the highest yield over 90% for CAS NCs were also achieved for the first time, which may be considered to be a green synthesis route compared with other conventional methods. Optical properties indicate that the as-prepared CAS NCs have strong optical absorption in the visible light region of the solar spectrum, and we also observed the band gap tunability of CuSbS2 and Cu3SbS4 materials for the first time. PMID:26875832

  4. The Copper Sulfide Coating on Polyacrylonitrile with Chelating Agents by an Electroless Deposition Method and its EMI Shielding Effectiveness

    SciTech Connect

    Roan, M.-L.; Chen, Y.-H.; Huang, C.-Y.

    2008-08-28

    In this study, a variety of concentrations of chelating agents were added to obtain the anchoring effect and chelating effect in the electroless plating bath. The mechanism of the Cu{sub x(x=1,2)}S growth and the electromagnetic interference shielding effectiveness (EMI SE) of the composite were studied. It was found that the vinyl acetate residued in PAN substrate would be purged due to the swelling effect by chelating agents solution. And then, the anchoring effect occurred due to the hydrogen bonding between the pits of PAN substrate and the chelating agent. Consequently, the copper sulfide layer deposited by the electroless plating reaction with EDTA and TEA. The swelling degree (S{sub d}) was proposed and evaluated from the FT-IR spectra. The relationship between swelling degree of the PAN films and EDTA (C) is expressed as: S{sub d} = 0.13+0.90xe and (-15.15C). And TEA series is expressed as: S{sub d} = 0.07+1.00xe and (-15.15C). On the other hand, the FESEM micrograph showed that the average thickness of copper sulfide increased from 76 nm to 383 nm when the concentration of EDTA increased from 0.00M to 0.20M. Consequently, the EMI SE of the composites increased from 10{approx}12 dB to 25{approx}27 dB. The GIA-XRD analyze indicated that the deposited layer consisted of CuS and Cu{sub 2}S.

  5. The Effect of Desulfovibrio sp. Biofilms on Corrosion Behavior of Copper in Sulfide-Containing Solutions

    NASA Astrophysics Data System (ADS)

    Güngör, Nihal Doğruöz; Çotuk, Ayşın; Dışpınar, Derya

    2015-03-01

    This study aims to detect the effect of Desulfovibrio sp. on copper in terms of biofilm formation and corrosion in 722 h. In that way, appropriate strategies to inhibit microbiological corrosion in copper systems with Desulfovibrio sp. can be evaluated. For this purpose, experiments were performed in 1 L glass model system containing 28 copper coupons and pure culture of the sulfate-reducing bacteria (SRB) strain Desulfovibrio sp. in Postgate's medium C. Also, a control system with copper coupons but without Desulfovibrio sp. containing sterile Postgate's medium was studied concurrently with the test system. The test coupons were collected from systems at certain time intervals, namely 24, 168, 360, and 720 h. The samples were then subjected to several characterization analyses such as measurement of Desulfovibrio sp. numbers, corrosion resistance, EPS extraction, carbohydrate analysis, SEM, and EDS. During the experiments, the maximum Desulfovibrio sp. count in biofilm samples was found at 360 h. Carbohydrate and copper concentrations in biofilm were increased over time. EDS analysis revealed Cu, S, C, O, and Cl peaks on the surface of the samples. For the control coupons, only Cu peaks were observed. The results obtained from this study showed that copper was corroded by Desulfovibrio sp. in the model system under laboratory conditions.

  6. Synthesis And Characterization of Copper Zinc Tin Sulfide Nanoparticles And Thin Films

    NASA Astrophysics Data System (ADS)

    Khare, Ankur

    Copper zinc tin sulfide (Cu2ZnSnS4, or CZTS) is emerging as an alternative material to the present thin film solar cell technologies such as Cu(In,Ga)Se2 and CdTe. All the elements in CZTS are abundant, environmentally benign, and inexpensive. In addition, CZTS has a band gap of ˜1.5 eV, the ideal value for converting the maximum amount of energy from the solar spectrum into electricity. CZTS has a high absorption coefficient (>104 cm-1 in the visible region of the electromagnetic spectrum) and only a few micron thick layer of CZTS can absorb all the photons with energies above its band gap. CZT(S,Se) solar cells have already reached power conversion efficiencies >10%. One of the ways to improve upon the CZTS power conversion efficiency is by using CZTS quantum dots as the photoactive material, which can potentially achieve efficiencies greater than the present thin film technologies at a fraction of the cost. However, two requirements for quantum-dot solar cells have yet to be demonstrated. First, no report has shown quantum confinement in CZTS nanocrystals. Second, the syntheses to date have not provided a range of nanocrystal sizes, which is necessary not only for fundamental studies but also for multijunction photovoltaic architectures. We resolved these two issues by demonstrating a simple synthesis of CZTS, Cu2SnS3, and alloyed (Cu2SnS3) x(ZnS)y nanocrystals with diameters ranging from 2 to 7 nm from diethyldithiocarbamate complexes. As-synthesized nanocrystals were characterized using high resolution transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and energy dispersive spectroscopy to confirm their phase purity. Nanocrystals of diameter less than 5 nm were found to exhibit a shift in their optical absorption spectra towards higher energy consistent with quantum confinement and previous theoretical predictions. Thin films from CZTS nanocrystals deposited on Mo-coated quartz substrates using drop casting were found to be continuous

  7. Formation and characterization of conductive thin layers of copper sulfide (Cu xS) on the surface of polyethylene and polyamide by the use of higher polythionic acids

    NASA Astrophysics Data System (ADS)

    Ancutiene, Ingrida; Janickis, Vitalijus; Ivanauskas, Remigijus

    2006-04-01

    Layers of copper sulfide of varying composition and properties are formed on the surface of polyethylene and polyamide by a sorption-diffusion method using solutions of higher polythionic acids, H 2S nO 6. The concentration of sulfur adsorbed-diffused into PE and PA depends on the degree of the acid sulfurity, n, the temperature of the solution and the period of the polymer treatment. The amount of copper in a sulfide (Cu xS) layer formed after the sulfured polymer treatment with a solution of Cu(I-II) salt is strongly dependent on the concentration of sulfur in the PE and PA. By the chemical analysis of the obtained sulfide layers was determined that a value of x in the Cu xS layers varies in the interval 1 < x < 2. The microscopic investigation of transverse sections of PE and PA samples with copper sulfide layers showed that the major part of copper sulfide is in the surface matrix of the polymer. X-ray diffraction studies of the Cu xS layers obtained seven phases: with x = 2 (chalcocite), 1.9375 (djurleite), 1.8 (digenite), 1.75 (anilite), 1.12 (yarrowite), 1.06 (talnakhite) and 1 (covellite). The measurements of the electrical conductance of Cu xS layers (0.1-4 S cm -2) showed that its value greatly depends on the conditions of PE and PA interaction with H 2S nO 6 and of further interaction with Cu(I-II) salt solution, on the chemical and phase composition of the layer.

  8. Optical and electrical stability of viral-templated copper sulfide (Cu{sub 1.8}S) films

    SciTech Connect

    Shahriar Zaman, Mohammed; Bernard Grajeda, Gabriel; Haberer, Elaine D.

    2014-04-14

    The optical and electrical stabilities of viral-templated non-stoichiometric copper sulfide, digenite (Cu{sub 1.8}S) films were investigated. The films were composed of large agglomerates of randomly aligned Cu{sub 1.8}S-coated M13 filamentous phage. Free carrier optical absorption associated with localized surface plasmon resonance (LSPR) was observed in the near infrared spectral region, and the films were electrically active, displaying a linear current-voltage relationship. Under ambient conditions, the magnitude of the LSPR absorption increased, following a power law relationship with time, and the electrical resistance of viral-templated films decreased significantly. In contrast, the resistance of films stored under low oxygen, low humidity conditions experienced a smaller reduction in electrical resistance. Changes in optical and electrical film properties under ambient conditions were associated with an increase in free carrier concentration within the copper chalcogenide material due to oxygen exposure. X-ray photoelectron spectroscopy was used to relate this increase in free carrier concentration to compositional changes on the viral-templated material surface.

  9. Copper sulfide nanoparticles with phospholipid-PEG coating for in vivo near-infrared photothermal cancer therapy.

    PubMed

    Huang, Yizhuan; Lai, Yulian; Shi, Saige; Hao, Shufang; Wei, Jingping; Chen, Xiaolan

    2015-02-01

    In this work, small sizes of hydrophobic copper sulfide nanoparticles (CuS NPs, ∼3.8 nm in diameter) have been successfully prepared from the reaction of copper chloride with sodium diethyldithiocarbamate (SDEDTC) inside a heated oleylamine solution. These CuS NPs displayed strong absorption in the 700-1100 nm near-infrared (NIR) region. By coating CuS NPs with DSPE-PEG2000 on the surface, the as-synthesized CuS@DSPE-PEG NPs exhibited good water solubility, significant stability and biocompatibility, as well as excellent photothermal conversion effects upon exposure to an 808 nm laser. After intravenous administration to mice, the CuS@DSPE-PEG NPs were found to passively target to the tumor site, and tumor tissues could be ablated efficiency under laser irradiation. In addition, CuS@DSPE-PEG NPs do not show significant toxicity by histological and blood chemistry analysis, and can be effectively excreted via metabolism. Our results indicated that CuS@DSPE-PEG NPs can act as an ideal photothermal agent for cancer photothermal therapy. PMID:25425287

  10. An efficient and transparent copper sulfide nanosheet film counter electrode for bifacial quantum dot-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ke, Weijun; Fang, Guojia; Lei, Hongwei; Qin, Pingli; Tao, Hong; Zeng, Wei; Wang, Jing; Zhao, Xingzhong

    2014-02-01

    Copper sulfide (CuS) with nanosheet structure has been synthesized at a low temperature in situ on copper (Cu) film coated fluorine-doped tin oxide glass and bifacial quantum dot-sensitized solar cells (QDSSCs) were herein developed by using these CuS as counter electrodes (CEs). CuS is an environmental compatible and low toxic material. The obtained two-dimensional CuS nanosheet film presents high carrier mobility and exhibits highly catalytic performance for the polysulfide-based electrolyte. The QDSSC based on a CuS CE presents a power conversion efficiency (PCE) of 3.65% by optimizing the thickness of the Cu film under front illumination. The QDSSC based on a CuS CE prepared with a 200 nm thick Cu film shows a very close PCE under front and rear illuminations in which the values are as high as 2.70% and 2.40%, respectively. All the PCEs of the CuS CEs are much higher than that of the Pt CE (1.34%).

  11. Lead isotope compositions of Late Cretaceous and early Tertiary igneous rocks and sulfide minerals in Arizona: Implications for the sources of plutons and metals in porphyry copper deposits

    USGS Publications Warehouse

    Bouse, R.M.; Ruiz, J.; Titley, S.R.; Tosdal, R.M.; Wooden, J.L.

    1999-01-01

    Porphyry copper deposits in Arizona are genetically associated with Late Cretaceous and early Tertiary igneous complexes that consist of older intermediate volcanic rocks and younger intermediate to felsic intrusions. The igneous complexes and their associated porphyry copper deposits were emplaced into an Early Proterozoic basement characterized by different rocks, geologic histories, and isotopic compositions. Lead isotope compositions of the Proterozoic basement rocks define, from northwest to southeast, the Mojave, central Arizona, and southeastern Arizona provinces. Porphyry copper deposits are present in each Pb isotope province. Lead isotope compositions of Late Cretaceous and early Tertiary plutons, together with those of sulfide minerals in porphyry copper deposits and of Proterozoic country rocks, place important constraints on genesis of the magmatic suites and the porphyry copper deposits themselves. The range of age-corrected Pb isotope compositions of plutons in 12 Late Cretaceous and early Tertiary igneous complexes is 206Pb/204Pb = 17.34 to 22.66, 207Pb/204Pb = 15.43 to 15.96, and 208Pb/204Pb = 37.19 to 40.33. These Pb isotope compositions and calculated model Th/U are similar to those of the Proterozoic rocks in which the plutons were emplaced, thereby indicating that Pb in the younger rocks and ore deposits was inherited from the basement rocks and their sources. No Pb isotope differences distinguish Late Cretaceous and early Tertiary igneous complexes that contain large economic porphyry copper deposits from less rich or smaller deposits that have not been considered economic for mining. Lead isotope compositions of Late Cretaceous and early Tertiary plutons and sulfide minerals from 30 metallic mineral districts, furthermore, require that the southeastern Arizona Pb province be divided into two subprovinces. The northern subprovince has generally lower 206Pb/204Pb and higher model Th/U, and the southern subprovince has higher 206Pb/204Pb and

  12. In situ solvothermal growth of metal-organic framework-5 supported on porous copper foam for noninvasive sampling of plant volatile sulfides.

    PubMed

    Hu, Yuling; Lian, Haixian; Zhou, Langjun; Li, Gongke

    2015-01-01

    The present study reported on an in situ solvothermal growth method for immobilization of metal-organic framework MOF-5 on porous copper foam support for enrichment of plant volatile sulfides. The porous copper support impregnated with mother liquor of MOF-5 anchors the nucleation and growth of MOF crystallites at its surface, and its architecture of the three-dimensional channel enables accommodation of the MOF-5 crystallite seed. A continuous and well-intergrown MOF-5 layer, evidenced from scanning electron microscope imaging and X-ray diffraction, was successfully immobilized on the porous metal bar with good adhesion and high stability. Results show that the resultant MOF-5 coating was thermally stable up to 420 °C and robust enough for replicate extraction for at least 200 times. The MOF-5 bar was then applied to the headspace sorptive extraction of the volatile organic sulfur compounds in Chinese chive and garlic sprout in combination with thermal desorption-gas chromatography/mass spectrometry. It showed high extraction sensitivity and good selectivity to these plant volatile sulfides owing to the extraordinary porosity of the metal-organic framework as well as the interaction between the S-donor sites and the surface cations at the crystal edges. Several primary sulfur volatiles containing allyl methyl sulfide, dimethyl disulfide, diallyl sulfide, methyl allyl disulfide, and diallyl disulfide were quantified. Their limits of detection were found to be in the range of 0.2-1.7 μg/L. The organic sulfides were detected in the range of 6.0-23.8 μg/g with recoveries of 76.6-100.2% in Chinese chive and 11.4-54.6 μg/g with recoveries of 77.1-99.8% in garlic sprout. The results indicate the immobilization of MOF-5 on copper foam provides an efficient enrichment formats for noninvasive sampling of plant volatiles. PMID:25435245

  13. Study of copper sulfide counter electrode on the performances of CdS/CdSe/ZnS-sensitized hierarchical TiO2 spheres quantum dots solar cells

    NASA Astrophysics Data System (ADS)

    Buatong, Nattha; Tang, I.-Ming; Pon-On, Weeraphat

    2015-07-01

    The effects of using copper sulfide (CuS) counter electrodes on the performances of solar cells made with CdS/CdSe/ZnS quantum dots co-sensitized onto hierarchical TiO2 spheres (HTS) used as photoelectrode is reported. The HTS in the QDSSCs is composed of an assembly of numerous TiO2 spheres made by the solvolthermal method. The photoelectrical performance of HTS/CdS/CdSe/ZnS coupled to CuS counter electrode was compared to those coupled to Pt CE. The HTS/CdS/CdSe/ZnS coupled to the CuS CE showed the highest power conversion efficiency η (of 1.310 %.) which is significantly higher than those using a standard Pt CE (η = 0.374%) (3.50 fold). This higher efficiency is the results of the higher electrocatalytic activities when the copper sulfide CEs is used.

  14. Iron sulfide attenuates the methanogenic toxicity of elemental copper and zinc oxide nanoparticles and their soluble metal ion analogs.

    PubMed

    Gonzalez-Estrella, Jorge; Gallagher, Sara; Sierra-Alvarez, Reyes; Field, Jim A

    2016-04-01

    Elemental copper (Cu(0)) and zinc oxide (ZnO) nanoparticle (NP) toxicity to methanogens has been attributed to the release of soluble metal ions. Iron sulfide (FeS) partially controls the soluble concentration of heavy metals and their toxicity in aquatic environments. Heavy metals displace the Fe from FeS forming poorly soluble metal sulfides in the FeS matrix. Therefore, FeS may be expected to attenuate the NP toxicity. This work assessed FeS as an attenuator of the methanogenic toxicity of Cu(0) and ZnO NPs and their soluble salt analogs. The toxicity attenuation capacity of fine (25-75μm) and coarse (500 to 1200μm) preparations of FeS (FeS-f and FeS-c respectively) was tested in the presence of highly inhibitory concentrations of CuCl2, ZnCl2 Cu(0) and ZnO NPs. FeS-f attenuated methanogenic toxicity better than FeS-c. The results revealed that 2.5× less FeS-f than FeS-c was required to recover the methanogenic activity to 50% (activity normalized to uninhibited controls). The results also indicated that a molar FeS-f/Cu(0) NP, FeS-f/ZnO NP, FeS-f/ZnCl2, and FeS-f/CuCl2 ratio of 2.14, 2.14, 4.28, and 8.56 respectively, was necessary to recover the methanogenic activity to >75%. Displacement experiments demonstrated that CuCl2 and ZnCl2 partially displaced Fe from FeS. As a whole, the results indicate that not all the sulfide in FeS was readily available to react with the soluble Cu and Zn ions which may explain the need for a large stoichiometric excess of FeS to highly attenuate Cu and Zn toxicity. Overall, this study provides evidence that FeS attenuates the toxicity caused by Cu(0) and ZnO NPs and their soluble ion analogs to methanogens. PMID:26803736

  15. Magmatic sulfide-rich nickel-copper deposits related to picrite and (or) tholeiitic basalt dike-sill complexes-A preliminary deposit model

    USGS Publications Warehouse

    Schulz, Klaus J.; Chandler, Val W.; Nicholson, Suzanne W.; Piatak, Nadine M.; Seal, Robert R., II; Woodruff, Laurel G.; Zientek, Michael L.

    2010-01-01

    Magmatic sulfide deposits containing nickel (Ni) and copper (Cu), with or without (?) platinum-group elements (PGEs), account for approximately 60 percent of the world's Ni production and are active exploration targets in the United States and elsewhere. On the basis of their principal metal production, magmatic sulfide deposits in mafic rocks can be divided into two major types: those that are sulfide-rich, typically with 10 to 90 percent sulfide minerals, and have economic value primarily because of their Ni and Cu contents; and those that are sulfide-poor, typically with 0.5 to 5 percent sulfide minerals, and are exploited principally for PGE. Because the purpose of this deposit model is to facilitate the assessment for undiscovered, potentially economic magmatic Ni-Cu?PGE sulfide deposits in the United States, it addresses only those deposits of economic significance that are likely to occur in the United States on the basis of known geology. Thus, this model focuses on deposits hosted by small- to medium-sized mafic and (or) ultramafic dikes and sills that are related to picrite and tholeiitic basalt magmatic systems generally emplaced in continental settings as a component of large igneous provinces (LIPs). World-class examples (those containing greater than 1 million tons Ni) of this deposit type include deposits at Noril'sk-Talnakh (Russia), Jinchuan (China), Pechenga (Russia), Voisey's Bay (Canada), and Kabanga (Tanzania). In the United States, this deposit type is represented by the Eagle deposit in northern Michigan, currently under development by Kennecott Minerals.

  16. Effect of Copper Sulfide Nanoparticles on the Optical and Electrical Behavior of Poly(vinyl alcohol) Films

    NASA Astrophysics Data System (ADS)

    Abdullah, Omed Gh.; Saleem, Salwan A.

    2016-07-01

    Polymer nanocomposite films based on poly(vinyl alcohol) (PVA) containing copper sulfide nanoparticles (CuS) were prepared using in situ chemical reduction and casting techniques. The synthesized nanocomposites were analyzed using x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope, and ultraviolet-visible spectroscopy. The XRD pattern reveals that the CuS nanoparticles incorporated in the PVA showed a crystalline nature. The observed FTIR band shifts indicate the intermolecular interaction between the CuS nanoparticles and the PVA matrix. The absorbance of nanocomposite samples increased with increasing CuS concentration. The optical band gap energy was estimated using Tauc's formula and it decreased with increasing dopant concentration. The conductivity and dielectric behavior of the samples were studied over the frequency range of 300 Hz to 1 MHz in the temperature range of 30-110°C. The ac conductivity was found to increase with the increase of dopant concentration as well as frequency. Moreover, the variation of frequency exponent (s) indicated that the conduction mechanism was the correlated barrier hopping model. The experimental results reveal that the optical and electrical performance of PVA can be enhanced dramatically by the addition of a small amount of CuS nanoparticles. This improved properties of the PVA/CuS nanocomposite suggest uses in optoelectronic devices.

  17. Size-tunable copper nanocluster aggregates and their application in hydrogen sulfide sensing on paper-based devices

    PubMed Central

    Chen, Po-Cheng; Li, Yu-Chi; Ma, Jia-Yin; Huang, Jia-Yu; Chen, Chien-Fu; Chang, Huan-Tsung

    2016-01-01

    Polystyrene sulfonate (PSS), a strong polyelectrolyte, was used to prepare red photoluminescent PSS-penicillamine (PA) copper (Cu) nanoclusters (NC) aggregates, which displayed high selectivity and sensitivity to the detection of hydrogen sulfide (H2S). The size of the PSS-PA-Cu NC aggregates could be readily controlled from 5.5 μm to 173 nm using different concentrations of PSS, which enabled better dispersity and higher sensitivity towards H2S. PSS-PA-Cu NC aggregates provided rapid H2S detection by using the strong Cu-S interaction to quench NC photoluminescence as a sensing mechanism. As a result, a detection limit of 650 nM, which is lower than the maximum level permitted in drinking water by the World Health Organization, was achieved for the analysis of H2S in spring-water samples. Moreover, highly dispersed PSS-PA-Cu NC aggregates could be incorporated into a plate-format paper-based analytical device which enables ultra-low sample volumes (5 μL) and feature shorter analysis times (30 min) compared to conventional solution-based methods. The advantages of low reagent consumption, rapid result readout, limited equipment, and long-term storage make this platform sensitive and simple enough to use without specialized training in resource constrained settings. PMID:27113330

  18. Formation of Copper Zinc Tin Sulfide Thin Films from Colloidal Nanocrystal Dispersions via Aerosol-Jet Printing and Compaction.

    PubMed

    Williams, Bryce A; Mahajan, Ankit; Smeaton, Michelle A; Holgate, Collin S; Aydil, Eray S; Francis, Lorraine F

    2015-06-01

    A three-step method to create dense polycrystalline semiconductor thin films from nanocrystal liquid dispersions is described. First, suitable substrates are coated with nanocrystals using aerosol-jet printing. Second, the porous nanocrystal coatings are compacted using a weighted roller or a hydraulic press to increase the coating density. Finally, the resulting coating is annealed for grain growth. The approach is demonstrated for making polycrystalline films of copper zinc tin sulfide (CZTS), a new solar absorber composed of earth-abundant elements. The range of coating morphologies accessible through aerosol-jet printing is examined and their formation mechanisms are revealed. Crack-free albeit porous films are obtained if most of the solvent in the aerosolized dispersion droplets containing the nanocrystals evaporates before they impinge on the substrate. In this case, nanocrystals agglomerate in flight and arrive at the substrate as solid spherical agglomerates. These porous coatings are mechanically compacted, and the density of the coating increases with compaction pressure. Dense coatings annealed in sulfur produce large-grain (>1 μm) polycrystalline CZTS films with microstructure suitable for thin-film solar cells. PMID:25989610

  19. Facile fabrication of novel porous graphitic carbon nitride/copper sulfide nanocomposites with enhanced visible light driven photocatalytic performance.

    PubMed

    Chen, Xi; Li, Huankun; Wu, Yuxin; Wu, Hanshuo; Wu, Laidi; Tan, Pengfei; Pan, Jun; Xiong, Xiang

    2016-08-15

    In this work, a novel organic-inorganic heterostructured photocatalyst: porous graphitic carbon nitride (g-C3N4) hybrid with copper sulfide (CuS) had been synthesized via a precipitation-deposition method at low temperature for the first time. UV-vis spectroscopy revealed the porous g-C3N4/CuS nanocomposites showed a strong and broad visible light absorption. Furthermore, the g-C3N4/CuS nanocomposites showed higher photocatalytic activity in the photodegradation of various organic dyes than that of pure g-C3N4 and CuS, and the selected sample of g-C3N4/CuS-2 exhibited the best photocatalytic activity under visible light. The good photocatalytic activity could be ascribed to the matching of the g-C3N4 and CuS band gap energies. Besides, photoluminescent spectra and photoelectrochemical measurements also proved that the CuS/g-C3N4 could greatly enhance the charge generation and suppress the charge recombination of photogenerated carriers. According to the experimental result, a possible photocatalytic mechanism has been proposed. Due to the high stability, the porous g-C3N4/CuS could be applied in the field of environmental remediation. Our work highlights that coupling semiconductors with well-matched band energies provides a facile way to improve the photocatalytic activity. PMID:27209398

  20. Size-tunable copper nanocluster aggregates and their application in hydrogen sulfide sensing on paper-based devices.

    PubMed

    Chen, Po-Cheng; Li, Yu-Chi; Ma, Jia-Yin; Huang, Jia-Yu; Chen, Chien-Fu; Chang, Huan-Tsung

    2016-01-01

    Polystyrene sulfonate (PSS), a strong polyelectrolyte, was used to prepare red photoluminescent PSS-penicillamine (PA) copper (Cu) nanoclusters (NC) aggregates, which displayed high selectivity and sensitivity to the detection of hydrogen sulfide (H2S). The size of the PSS-PA-Cu NC aggregates could be readily controlled from 5.5 μm to 173 nm using different concentrations of PSS, which enabled better dispersity and higher sensitivity towards H2S. PSS-PA-Cu NC aggregates provided rapid H2S detection by using the strong Cu-S interaction to quench NC photoluminescence as a sensing mechanism. As a result, a detection limit of 650 nM, which is lower than the maximum level permitted in drinking water by the World Health Organization, was achieved for the analysis of H2S in spring-water samples. Moreover, highly dispersed PSS-PA-Cu NC aggregates could be incorporated into a plate-format paper-based analytical device which enables ultra-low sample volumes (5 μL) and feature shorter analysis times (30 min) compared to conventional solution-based methods. The advantages of low reagent consumption, rapid result readout, limited equipment, and long-term storage make this platform sensitive and simple enough to use without specialized training in resource constrained settings. PMID:27113330

  1. Size-tunable copper nanocluster aggregates and their application in hydrogen sulfide sensing on paper-based devices

    NASA Astrophysics Data System (ADS)

    Chen, Po-Cheng; Li, Yu-Chi; Ma, Jia-Yin; Huang, Jia-Yu; Chen, Chien-Fu; Chang, Huan-Tsung

    2016-04-01

    Polystyrene sulfonate (PSS), a strong polyelectrolyte, was used to prepare red photoluminescent PSS-penicillamine (PA) copper (Cu) nanoclusters (NC) aggregates, which displayed high selectivity and sensitivity to the detection of hydrogen sulfide (H2S). The size of the PSS-PA-Cu NC aggregates could be readily controlled from 5.5 μm to 173 nm using different concentrations of PSS, which enabled better dispersity and higher sensitivity towards H2S. PSS-PA-Cu NC aggregates provided rapid H2S detection by using the strong Cu-S interaction to quench NC photoluminescence as a sensing mechanism. As a result, a detection limit of 650 nM, which is lower than the maximum level permitted in drinking water by the World Health Organization, was achieved for the analysis of H2S in spring-water samples. Moreover, highly dispersed PSS-PA-Cu NC aggregates could be incorporated into a plate-format paper-based analytical device which enables ultra-low sample volumes (5 μL) and feature shorter analysis times (30 min) compared to conventional solution-based methods. The advantages of low reagent consumption, rapid result readout, limited equipment, and long-term storage make this platform sensitive and simple enough to use without specialized training in resource constrained settings.

  2. Light-induced cation exchange for copper sulfide based CO2 reduction.

    PubMed

    Manzi, Aurora; Simon, Thomas; Sonnleitner, Clemens; Döblinger, Markus; Wyrwich, Regina; Stern, Omar; Stolarczyk, Jacek K; Feldmann, Jochen

    2015-11-11

    Copper(I)-based catalysts, such as Cu2S, are considered to be very promising materials for photocatalytic CO2 reduction. A common synthesis route for Cu2S via cation exchange from CdS nanocrystals requires Cu(I) precursors, organic solvents, and neutral atmosphere, but these conditions are not compatible with in situ applications in photocatalysis. Here we propose a novel cation exchange reaction that takes advantage of the reducing potential of photoexcited electrons in the conduction band of CdS and proceeds with Cu(II) precursors in an aqueous environment and under aerobic conditions. We show that the synthesized Cu2S photocatalyst can be efficiently used for the reduction of CO2 to carbon monoxide and methane, achieving formation rates of 3.02 and 0.13 μmol h(-1) g(-1), respectively, and suppressing competing water reduction. The process opens new pathways for the preparation of new efficient photocatalysts from readily available nanostructured templates. PMID:26479775

  3. A Comparative Study of Hollow Copper Sulfide Nanoparticles and Hollow Gold Nanospheres on Degradability and Toxicity

    PubMed Central

    Guo, Liangran; Panderi, Irene; Yan, Daisy D.; Szulak, Kevin; Li, Yajuan; Chen, Yi-Tzai; Ma, Hang; Niesen, Daniel B.; Seeram, Navindra; Ahmed, Aftab; Yan, Bingfang; Pantazatos, Dionysios; Lu, Wei

    2013-01-01

    Gold and copper nanoparticles have been widely investigated for photothermal therapy of cancer. However, degradability and toxicity of these nanoparticles remain concerns. Here, we compare hollow CuS nanoparticles (HCuSNPs) with hollow gold nanospheres (HAuNS) in similar particle sizes and morphology following intravenous administration to mice. The injected pegylated HCuSNPs (PEG-HCuSNPs) are eliminated through both hepatobiliary (67 percentage of injected dose, %ID) and renal (23 %ID) excretion within one month post injection. By contrast, 3.98 %ID of Au is excreted from liver and kidney within one month after i.v. injection of pegylated HAuNS (PEG-HAuNS). Comparatively, PEG-HAuNS are almost non-metabolizable, while PEG-HCuSNPs are considered biodegradable nanoparticles. PEG-HCuSNPs do not show significant toxicity by histological or blood chemistry analysis. Principal component analysis and 2-D peak distribution plots of data from matrix-assisted laser desorption ionization-time of flight imaging mass spectrometry (MALDI-TOF IMS) of liver tissues demonstrated a reversible change in the proteomic profile in mice receiving PEG-HCuSNPs. This is attributed to slow dissociation of Cu ion from CuS nanoparticles along with effective Cu elimination for maintaining homeostasis. Nonetheless, an irreversible change in the proteomic profile is observed in the liver from mice receiving PEG-HAuNS by analysis of MALDI-TOF IMS data, probably due to the non-metabolizability of Au. This finding correlates with the elevated serum lactate dehydrogenase at 3 months after PEG-HAuNS injection, indicating potential long-term toxicity. The comparative results between the two types of nanoparticles will advance the development of HCuSNPs as a new class of biodegradable inorganic nanomaterials for photothermal therapy. PMID:24053214

  4. Low-temperature approach to highly emissive copper indium sulfide colloidal nanocrystals and their bioimaging applications.

    PubMed

    Yu, Kui; Ng, Peter; Ouyang, Jianying; Zaman, Md Badruz; Abulrob, Abedelnasser; Baral, Toya Nath; Fatehi, Dorothy; Jakubek, Zygmunt J; Kingston, David; Wu, Xiaohua; Liu, Xiangyang; Hebert, Charlie; Leek, Donald M; Whitfield, Dennis M

    2013-04-24

    We report our newly developed low-temperature synthesis of colloidal photoluminescent (PL) CuInS2 nanocrystals (NCs) and their in vitro and in vivo imaging applications. With diphenylphosphine sulphide (SDPP) as a S precursor made from elemental S and diphenylphosphine, this is a noninjection based approach in 1-dodecanethiol (DDT) with excellent synthetic reproducibility and large-scale capability. For a typical synthesis with copper iodide (CuI) as a Cu source and indium acetate (In(OAc)3) as an In source, the growth temperature was as low as 160 °C and the feed molar ratios were 1Cu-to-1In-to-4S. Amazingly, the resulting CuInS2 NCs in toluene exhibit quantum yield (QY) of ~23% with photoemission peaking at ~760 nm and full width at half maximum (FWHM) of ~140 nm. With a mean size of ~3.4 nm (measured from the vertices to the bases of the pyramids), they are pyramidal in shape with a crystal structure of tetragonal chalcopyrite. In situ (31)P NMR (monitored from 30 °C to 100 °C) and in situ absorption at 80 °C suggested that the Cu precursor should be less reactive toward SDPP than the In precursor. For our in vitro and in vivo imaging applications, CuInS2/ZnS core-shell QDs were synthesized; afterwards, dihydrolipoic acid (DHLA) or 11-mercaptoundecanoic acid (MUA) were used for ligand exchange and then bio-conjugation was performed. Two single-domain antibodies (sdAbs) were used. One was 2A3 for in vitro imaging of BxPC3 pancreatic cancer cells. The other was EG2 for in vivo imaging of a Glioblastoma U87MG brain tumour model. The bioimaging data illustrate that the CuInS2 NCs from our SDPP-based low-temperature noninjection approach are good quality. PMID:23486927

  5. Synthesis and Characterization of Phase-pure Copper Zinc Tin Sulfide (Cu2ZnSnS4) Nanoparticles

    NASA Astrophysics Data System (ADS)

    Monahan, Bradley Michael

    Semiconductor nanoparticles have been an important area of research in many different disciplines. A substantial amount of this work has been put toward advancing the field of photovoltaics. However, current p-type photovoltaic materials can not sustain the large scale production needed for future energy demands due to their low elemental abundance. Therefore, Earth abundant semiconductor materials have become of great interest to the photovoltaic community especially, the material copper zinc tin sulfide (CZTS), also known by its mineral name kesterite. CZTS exhibits desirable properties for photovoltaics, such as elemental abundance, high absorption coefficient (~104 cm-1 ), high carrier concentration, and optimum direct band gap (1.5 eV). To date, solution based approaches for making CZTS have yielded the most promising conversion efficiencies in solar cells. To that end, the motivation of nanoparticle based inks that can be used in high throughput production are an attractive route for large scale deployment. This has driven the need to make high quality CZTS nanoparticles that possess the properties of the pure kesterite phase with high monodispersity that can be deposited into dense thin films. The inherent challenge of making a quaternary compound of a single phase has made this a difficult task; however, some of those fundamental problems are addressed in this thesis. This had resulted in the synthesis of phase-pure k-CZTS confirmed by powder X-ray diffraction, Raman spectroscopy, UV-visible absorption spectroscopy and energy dispersive x-ray spectroscopy. Furthermore, ultra-fast laser spectroscopy was done on CZTS thin films made from phase-pure kesterite nanoparticles synthesized in this work. This thesis provides new data that directly probes the lifetime of photogenerated free carriers in kesterite CZTS (k-CZTS) thin films.

  6. Reaction Mechanisms of Metals with Hydrogen Sulfide and Thiols in Model Wine. Part 2: Iron- and Copper-Catalyzed Oxidation.

    PubMed

    Kreitman, Gal Y; Danilewicz, John C; Jeffery, David W; Elias, Ryan J

    2016-05-25

    Sulfidic off-odors arising during wine production are frequently removed by Cu(II) fining. In part 1 of this study ( 10.1021/acs.jafc.6b00641 ), the reaction of H2S and thiols with Cu(II) was examined; however, the interaction of iron and copper is also known to play an important synergistic role in mediating non-enzymatic wine oxidation. The interaction of these two metals in the oxidation of H2S and thiols (cysteine, 3-sulfanylhexan-1-ol, and 6-sulfanylhexan-1-ol) was therefore examined under wine-like conditions. H2S and thiols (300 μM) were reacted with Fe(III) (100 or 200 μM) alone and in combination with Cu(II) (25 or 50 μM), and concentrations of H2S and thiols, oxygen, and acetaldehyde were monitored over time. H2S and thiols were shown to be slowly oxidized in the presence of Fe(III) alone and were not bound to Fe(III) under model wine conditions. However, Cu(II) added to model wine containing Fe(III) was quickly reduced by H2S and thiols to form Cu(I) complexes, which then rapidly reduced Fe(III) to Fe(II). Oxidation of Fe(II) in the presence of oxygen regenerated Fe(III) and completed the iron redox cycle. In addition, sulfur-derived oxidation products were observed, and the formation of organic polysulfanes was demonstrated. PMID:27133088

  7. Study of the Susceptibility of Oxygen-Free Phosphorous Doped Copper to Corrosion in Simulated Groundwater in the Presence of Chloride and Sulfide

    SciTech Connect

    Escobar, Ivan; Lamas, Claudia; Werme, Lars |; Oversby, Virginia

    2007-07-01

    Oxygen free high conductivity copper, doped with phosphorus (Cu OFP) has been chosen as the material for the fabrication of high level nuclear waste containers in Sweden. This material will be the corrosion barrier for spent fuel in the environment of a deep geological repository in granitic rock. The service life of this container is expected to exceed 1,000,000 years. During this time, which includes several glaciations, water of different compositions, including high concentration of chloride ions, will contact the copper surface. This work reports a study of the susceptibility of Cu OFP to corrosion when chloride ions are present, in deionized water (DW) and in synthetic groundwater (SGW). The techniques used were electrochemical methods such as corrosion potential evolution and Tafel curves. The system was studied with Electrochemical Impedance Spectroscopy (EIS). We also used as characterization techniques Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The main conclusions are that copper is more susceptible to corrosion at high chloride ion concentration. When the chloride concentration is low, it is possible to form copper chloride crystals, but at the highest concentration, copper chloride complexes are formed, leaving the copper surface without deposits. When the chloride concentration is low (<0.1 M) the corrosion process is mainly controlled by diffusion, while at higher concentrations (0.1 M to 1 M) corrosion is controlled by charge transfer processes. At low concentration of sulfide (<3 . 10{sup -5} M), copper corrosion in the presence of chloride is controlled by diffusional processes, while at higher concentrations corrosion is controlled by charge transfer processes. (authors)

  8. Evolution of 3-mercaptohexanol, hydrogen sulfide, and methyl mercaptan during bottle storage of Sauvignon blanc wines. Effect of glutathione, copper, oxygen exposure, and closure-derived oxygen.

    PubMed

    Ugliano, Maurizio; Kwiatkowski, Mariola; Vidal, Stéphane; Capone, Dimitra; Siebert, Tracey; Dieval, Jean-Baptiste; Aagaard, Olav; Waters, Elizabeth J

    2011-03-23

    The effects of wine composition and postbottling oxygen exposure on 3-mercaptohexanol (3-MH), hydrogen sulfide (H2S), and methyl mercaptan (MeSH) were investigated. A Sauvignon blanc wine with initial copper concentration of 0.1 mg/L was treated with copper sulfate and/or glutathione (GSH) prior to bottling to give final concentrations of 0.3 and 20 mg/L, respectively. The wines were bottled with a synthetic closure previously stored in either ambient air or nitrogen to study the effect of the oxygen normally present in the closure. Bottled wines were stored for 6 months in either air or nitrogen to study the effect of oxygen ingress through the closure. Copper addition resulted in a rapid initial decrease in 3-MH. During storage, a further decrease of 3-MH was observed, which was lower with GSH addition and lowered oxygen exposure. H2S accumulated largely during the second 3 months of bottle storage, with the highest concentrations attained in the wines treated with GSH and copper. Lower oxygen from and through the closure promoted H2S accumulation. The concentration of MeSH was virtually not affected by the experimental variables at 6 months, although differences were observed after 3 months of storage. The implications for wine quality are discussed. PMID:21332202

  9. Petrography, sulfide mineral chemistry, and sulfur isotope evidence for a hydrothermal imprint on Musina copper deposits, Limpopo Province, South Africa: Evidence for a breccia pipe origin?

    NASA Astrophysics Data System (ADS)

    Chaumba, Jeff B.; Mundalamo, Humbulani R.; Ogola, Jason S.; Cox, J. A.; Fleisher, C. J.

    2016-08-01

    The Musina copper deposits are located in the Central Zone of the Limpopo orogenic belt in Limpopo Province, South Africa. We carried out a petrographic, sulfide composition, and δ34S study on samples from Artonvilla and Campbell copper deposits and a country rock granitic gneiss to Artonvilla Mine to place some constrains on the origin of these deposits. The assemblages at both Artonvilla and Campbell Mines of brecciated quartz, potassium feldspar, muscovite, chlorite, calcite, and amphibole are consistent with sericitic alteration. Quartz, amphibole, feldspars, and micas often display angular textures which are consistent with breccias. Sulfur concentrations in pyrite from Artonvilla Mine plot in a narrow range, from 50.2 wt. % to 55.7 wt. %. With the exception of a positive correlation between Fe and Cu, no well defined correlations are shown by data from the Musina copper deposits. The occurrence of sulfides both as inclusions in, or as interstitial phases in silicates, suggests that hydrothermal alteration that affected these deposits most likely helped concentrate the mineralization at the Musina copper deposits. Sulfur concentrations in chalcopyrite samples investigated vary widely whereas the copper concentrations in chalcopyrite are not unusually higher compared to those from chalcopyrite from other tectonic settings, probably indicating that either the Cu in the Musina copper deposits occurs in native form, and/or that it is hosted by other phases. This observation lends support to the Cu having been concentrated during a later hydrothermal event. One sample from Artonvilla Mine (AtCal01) yielded pyrite δ34S values of 3.1and 3.6‰ and chalcopyrite from the same sample yielded a value of 3.9‰. A country rock granitic gneiss to Artonvilla Mine yielded a δ34Spyrite value of 8.2‰. For Campbell Mine samples, one quartz vein sample has a δ34Spyrite value of 0.5‰ whereas chalcopyrite samples drilled from different areas within the same sample

  10. COPPER

    EPA Science Inventory

    The report is a review of current knowledge of the distribution of copper in the environment and living things. Metabolism and the effects of copper in the biosphere are also considered. Copper compounds are common and widely distributed in nature. They are also extensively mined...

  11. Cu1.94S-Assisted Growth of Wurtzite CuInS2 Nanoleaves by In Situ Copper Sulfidation.

    PubMed

    Cai, Chunqi; Zhai, Lanlan; Zou, Chao; Li, Zhensong; Zhang, Lijie; Yang, Yun; Huang, Shaoming

    2015-12-01

    Wurtzite CuInS2 nanoleaves were synthesized by Cu1.94S-assisted growth. By observing the evolution of structures and phases during the growth process, Cu1.94S nanocrystals were found to be formed after uninterrupted oxidation and sulfidation of copper nanoparticles at the early stage, serving as catalysts to introduce the Cu and In species into CuInS2 nanoleaves growth for inherent property of fast ionic conductor. The obtained CuInS2 nanoleaves were characterized by scanning transmission electron microscopy, transmission electron microscopy, fast Fourier transform, X-ray diffraction, and energy dispersive X-ray spectroscopy mapping. The enhancement of photoresponsive current of CuInS2 nanoleaf film, evaluated by I-V curves of nanoleaf film, is believed to be attributed to the fast carrier transport benefit from the nature of single crystalline of CuInS2 nanoleaves. PMID:26173675

  12. Removal of copper from ferrous scrap

    DOEpatents

    Blander, M.; Sinha, S.N.

    1990-05-15

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  13. Removal of copper from ferrous scrap

    DOEpatents

    Blander, Milton; Sinha, Shome N.

    1990-01-01

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  14. Removal of copper from ferrous scrap

    DOEpatents

    Blander, M.; Sinha, S.N.

    1987-07-30

    A process for removing copper from ferrous or other metal scrap in which the scrap is contacted with a polyvalent metal sulfide slag in the presence of an excess of copper-sulfide forming additive to convert the copper to copper sulfide which is extracted into the slag to provide a ratio of copper in the slag to copper in the metal scrap of at least about 10.

  15. Facile room-temperature synthesis of carboxylated graphene oxide-copper sulfide nanocomposite with high photodegradation and disinfection activities under solar light irradiation

    PubMed Central

    Yu, Shuyan; Liu, Jincheng; Zhu, Wenyu; Hu, Zhong-Ting; Lim, Teik-Thye; Yan, Xiaoli

    2015-01-01

    Carboxylic acid functionalized graphene oxide-copper (II) sulfide nanoparticle composite (GO-COOH-CuS) was prepared from carboxylated graphene oxide and copper precursor in dimethyl sulfoxide (DMSO) by a facile synthesis process at room temperature. The high-effective combination, the interaction between GO-COOH sheets and CuS nanoparticles, and the enhanced visible light absorption were confirmed by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra (DRS) and Photoluminescence (PL) spectra. The as-synthesized GO-COOH-CuS nanocomposite exhibited excellent photocatalytic degradation performance of phenol and rhodamine B, high antibacterial activity toward E. coli and B. subtilis, and good recovery and reusability. The influence of CuS content, the synergistic reaction between CuS and GO-COOH, and the charge-transfer mechanism were systematically investigated. The facile and low-energy synthesis process combined with the excellent degradation and antibacterial performance signify that the GO-COOH-CuS has a great potential for water treatment application. PMID:26553709

  16. Facile room-temperature synthesis of carboxylated graphene oxide-copper sulfide nanocomposite with high photodegradation and disinfection activities under solar light irradiation

    NASA Astrophysics Data System (ADS)

    Yu, Shuyan; Liu, Jincheng; Zhu, Wenyu; Hu, Zhong-Ting; Lim, Teik-Thye; Yan, Xiaoli

    2015-11-01

    Carboxylic acid functionalized graphene oxide-copper (II) sulfide nanoparticle composite (GO-COOH-CuS) was prepared from carboxylated graphene oxide and copper precursor in dimethyl sulfoxide (DMSO) by a facile synthesis process at room temperature. The high-effective combination, the interaction between GO-COOH sheets and CuS nanoparticles, and the enhanced visible light absorption were confirmed by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra (DRS) and Photoluminescence (PL) spectra. The as-synthesized GO-COOH-CuS nanocomposite exhibited excellent photocatalytic degradation performance of phenol and rhodamine B, high antibacterial activity toward E. coli and B. subtilis, and good recovery and reusability. The influence of CuS content, the synergistic reaction between CuS and GO-COOH, and the charge-transfer mechanism were systematically investigated. The facile and low-energy synthesis process combined with the excellent degradation and antibacterial performance signify that the GO-COOH-CuS has a great potential for water treatment application.

  17. Facile room-temperature synthesis of carboxylated graphene oxide-copper sulfide nanocomposite with high photodegradation and disinfection activities under solar light irradiation.

    PubMed

    Yu, Shuyan; Liu, Jincheng; Zhu, Wenyu; Hu, Zhong-Ting; Lim, Teik-Thye; Yan, Xiaoli

    2015-01-01

    Carboxylic acid functionalized graphene oxide-copper (II) sulfide nanoparticle composite (GO-COOH-CuS) was prepared from carboxylated graphene oxide and copper precursor in dimethyl sulfoxide (DMSO) by a facile synthesis process at room temperature. The high-effective combination, the interaction between GO-COOH sheets and CuS nanoparticles, and the enhanced visible light absorption were confirmed by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra (DRS) and Photoluminescence (PL) spectra. The as-synthesized GO-COOH-CuS nanocomposite exhibited excellent photocatalytic degradation performance of phenol and rhodamine B, high antibacterial activity toward E. coli and B. subtilis, and good recovery and reusability. The influence of CuS content, the synergistic reaction between CuS and GO-COOH, and the charge-transfer mechanism were systematically investigated. The facile and low-energy synthesis process combined with the excellent degradation and antibacterial performance signify that the GO-COOH-CuS has a great potential for water treatment application. PMID:26553709

  18. Temperature-dependent formation of metallic copper and metal sulfide nanoparticles during flooding of a contaminated soil

    NASA Astrophysics Data System (ADS)

    Hofacker, Anke F.; Voegelin, Andreas; Kaegi, Ralf; Weber, Frank-Andreas; Kretzschmar, Ruben

    2013-02-01

    Riparian floodplains in temperate regions are affected by pronounced seasonal variations in soil and water temperature. This affects the rates and interplay of microbial and abiotic geochemical processes that control the fate of metals in contaminated floodplain soils, including potential release into surface and groundwater during periodic flooding. Here, we investigated how temperature affects chalcophile trace metal contaminants (Cu, Cd, Pb) upon flooding of a riparian soil contaminated by past mining activities. In soil microcosms incubated at 23, 14, and 5 °C, the reductive dissolution of Mn(III,IV) and Fe(III) (oxyhydr)oxides and the release of dissolved Mn2+ and Fe2+ were significantly slower and less intense at the lower temperatures, which was reflected in a decrease of trace metal mobilization via the dissolution of metal oxide sorbents and cation competition for sorption sites. The onset of sulfate reduction was significantly delayed at lower temperatures and the apparent rate of sulfate reduction was decreased, especially at 5 °C. This resulted in elevated high dissolved Cu, Cd, and Pb concentrations over weeks of flooding at 5 °C, whereas colloidal metal sulfide formation dominated Cu, Cd, and Pb pore water dynamics at higher temperatures of 14 and 23 °C due to fast sulfate reduction. Cu K-edge X-ray absorption fine structure spectroscopy revealed metallic Cu(0) as the main colloidal Cu species prior to sulfate reduction at all three temperatures. Analytical electron microscopy showed that Cu(0) particles were associated with suspended bacteria, suggesting biomineralization of Cu(0). Upon onset of sulfate reduction, metallic Cu particles were transformed into CuxS with incorporation of smaller amounts of Cd and Pb. Concomitantly, freely dispersed mixed Cu-Cd-Pb sulfide nanoparticles precipitated in the pore water. Other metals with higher metal sulfide solubility products did not react with the limited amounts of biogenic sulfide. The median size

  19. Photocatalytic Activities of Copper Doped Cadmium Sulfide Microspheres Prepared by a Facile Ultrasonic Spray-Pyrolysis Method.

    PubMed

    Su, Jinzhan; Zhang, Tao; Li, Yufeng; Chen, Yubin; Liu, Maochang

    2016-01-01

    Ultrasonic spray pyrolysis is a superior method for preparing and synthesizing spherical particles of metal oxide or sulfide semiconductors. Cadmium sulfide (CdS) photocatalysts with different sizes and doped-CdS with different dopants and doping levels have been synthesized to study their properties of photocatalytic hydrogen production from water. The CdS photocatalysts were characterized with scanning electron microscopy (SEM), X-ray fluorescence-spectrometry (XRF), UV-Vis absorption spectra and X-ray diffraction (XRD) to study their morphological and optical properties. The sizes of the prepared CdS particles were found to be proportional to the concentration of the metal nitrates in the solution. The CdS photocatalyst with smaller size showed a better photocatalytic activity. In addition, Cu doped CdS were also deposited and their photocatalytic activities were also investigated. Decreased bandgaps of CdS synthesized with this method were found and could be due to high density surface defects originated from Cd vacancies. Incorporating the Cu elements increased the bandgap by taking the position of Cd vacancies and reducing the surface defect states. The optimal Cu-doped level was found to be 0.5 mol % toward hydrogen evolution from aqueous media in the presence of sacrificial electron donors (Na₂S and Na₂SO₃) at a pH of 13.2. This study demonstrated that ultrasonic spray pyrolysis is a feasible approach for large-scale photocatalyst synthesis and corresponding doping modification. PMID:27314320

  20. High color rendering index white light emitting diodes fabricated from a combination of carbon dots and zinc copper indium sulfide quantum dots

    SciTech Connect

    Sun, Chun; Liu, Wenyan; Zhang, Xiaoyu; Zhang, Yu E-mail: wyu6000@gmail.com; Wang, Yu; Kalytchuk, Sergii; Kershaw, Stephen V.; Rogach, Andrey L.; Zhang, Tieqiang; Zhao, Jun; Yu, William W. E-mail: wyu6000@gmail.com

    2014-06-30

    In a line with most recent trends in developing non-toxic fluorescent nanomaterials, we combined blue emissive carbon dots with green and red emissive zinc copper indium sulfide (ZCIS) core/shell quantum dots (QDs) to achieve white light-emitting diodes (WLEDs) with a high color rendering index of 93. This indicates that ZCIS QDs, with their broad emission bands, can be employed to effectively make up the emission of carbon dots in the yellow and red regions to produce WLEDs in the wide region of color temperature by tuning the volume ratio of these constituting luminophores. Their electroluminescence characteristics including color rendering index, Commission Internationale de l'Eclairage (CIE) color coordinates, and color temperatures were evaluated as a function of forward current. The CIE-1931 chromaticity coordinates of the as-prepared WLEDs, exhibiting good stability, were slightly shifted from (0.321, 0.312) at 10 mA to (0.351, 0.322) at 30 mA, which was mainly caused by the different thermal quenching coefficients of carbon dots and ZCIS QDs.

  1. An efficient dual-loaded multifunctional nanocarrier for combined photothermal and photodynamic therapy based on copper sulfide and chlorin e6.

    PubMed

    Tan, Xiaoxiao; Pang, Xiaojuan; Lei, Mingzhu; Ma, Man; Guo, Fang; Wang, Jinping; Yu, Meng; Tan, Fengping; Li, Nan

    2016-04-30

    The therapeutic effectiveness of photodynamic therapy (PDT) was hampered by the poor water solubility and instability in physiological conditions of the photosensitizers. Here, we designed folate conjugated thermosensitive liposomes (TSL) as the nanocarrier to improve the solubility, stability and biocompatibility of photosensitizer Chlorin e6 (Ce6). Based on the photothermal effect, we combined copper sulfide (CuS) as the photothermal agent to realize heat-triggered Ce6 release as well as synergistic effect of photothermal and photodynamic therapy. In vitro MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that Ce6-CuS-TSL had low dark toxicity, while performed excellent phototoxicity under the combined 660 and 808nm laser irradiation compared to any single laser irradiation alone. Moreover, in vivo combination therapy study revealed that Ce6-CuS-TSL inhibited tumor growth to a great extent without evident side effect under the laser irradiation. All detailed evidence demonstrated a considerable potential of Ce6-CuS-TSL for synergistic cancer treatment. PMID:26988376

  2. Copper

    Integrated Risk Information System (IRIS)

    Copper ; CASRN 7440 - 50 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects )

  3. Fluorescence signaling of hydrogen sulfide in broad pH range using a copper complex based on BINOL-benzimidazole ligands.

    PubMed

    Sun, Mingtai; Yu, Huan; Li, Huihui; Xu, Hongda; Huang, Dejian; Wang, Suhua

    2015-04-20

    A weakly fluorescent complex derived from a binaphthol-benzimidazole ligand was designed and synthesized for hydrogen sulfide at different pH conditions. It was demonstrated that the probe showed the same reactivity to various hydrogen sulfide species in a broad range of pH values to generate highly fluorescent product through a displacement reaction mechanism, whereas the product's fluorescence spectrum exhibited a hypsochromic shift of ∼73 nm (2393 cm(-1)) as pH increased from neutral to basic, which can be used for distinguishing the various species of hydrogen sulfide. This turn-on fluorescence probe was highly selective and sensitive to hydrogen sulfide with a detection limit of 0.11 μM. It was then applied for evaluating the total content of sulfide (including hydrogen sulfide, hydrosulfide, and sulfide) as well as for the visual detection of gaseous H2S in air using a simple test paper strip. PMID:25839192

  4. Selenium Sulfide

    MedlinePlus

    Selenium sulfide, an anti-infective agent, relieves itching and flaking of the scalp and removes the dry, ... Selenium sulfide comes in a lotion and is usually applied as a shampoo. As a shampoo, selenium ...

  5. Copper-doped silica materials silanized with bis-(triethoxy silyl propyl)-tetra sulfide for mercury vapor capture

    SciTech Connect

    D.E. Meyer; N. Meeks; S. Sikdar; N.D. Hutson; D. Hua; D. Bhattacharyya

    2008-07-15

    The use of Cu-S sites for Hg capture from the gas phase has been successfully applied to a silica-based platform using an S4 organic polysulfane and copper sulfate. The maximum fixed-bed equilibrium capacity achieved using these materials was 19 789 {mu}g Hg.g{sup -1} sorbent for a material with 2.5 wt % Cu and 6 wt % S. An optimal S level was determined to be around 3 wt % because enhancement of capacity was only 18% when increasing from this 3 to 6 wt %. The rate of adsorption in pure beds ranged from 0.6 to 1.6 {mu}g Hg.min{sup -1} depending on the inlet concentration. Differences in breakthrough times suggest that material deposition is not uniform. When compared to two other platforms, commercially available Darco HG-LH and previously tested Fe-Cu-S4 nanoaggregates, the Si-1 material performed the best in fixed-bed testing. During entrained-flow testing, a steady-state Hg removal of 82% was achieved using Si-1 at injection rates of both 6 x 10{sup -5} and 1.2 x 10{sup -4} g.L{sup -1}.h{sup -1}. The lack of increase in Hg removal when the injection rate is doubled suggests that pore accessibility is the rate-controlling step during dynamic Hg capture. A calculation of the approximate pore usage based on injection testing helped confirm this observation. During injection testing, the performance of Si-1 was only diminished 10% when exposed to 20 ppm SO{sub 3}. This is an encouraging result for flue-gas applications where SO{sub 3} levels range from 1 to 40 ppm. Testing demonstrated that Si-1 is stable when exposed to leaching conditions after concrete blending and cement impregnation. This is an important aspect to consider for injection because the sale of fly ash for concrete is a key cost-recovery tool for power plants. 27 refs., 8 figs., 5 tabs.

  6. Structural, optical and charge generation properties of chalcostibite and tetrahedrite copper antimony sulfide thin films prepared from metal xanthates† †Electronic supplementary information (ESI) available: Chemical structures of the used metal xanthates, additional XRD, SEM-EDX and UV-vis data. See DOI: 10.1039/c5ta05777a Click here for additional data file.

    PubMed Central

    MacLachlan, Andrew J.; Brown, Michael D.

    2015-01-01

    Herein, we report on a solution based approach for the preparation of thin films of copper antimony sulfide, an emerging absorber material for third generation solar cells. In this work, copper and antimony xanthates are used as precursor materials for the formation of two different copper antimony sulfide phases: chalcostibite (CuSbS2) and tetrahedrite (Cu12Sb4S13). Both phases were thoroughly investigated regarding their structural and optical properties. Moreover, thin films of chalcostibite and tetrahedrite were prepared on mesoporous TiO2 layers and photoinduced charge transfer in these metal sulfide/TiO2 heterojunctions was studied via transient absorption spectroscopy. Photoinduced charge transfer was detected in both the chalcostibite as well as the tetrahedrite sample, which is an essential property in view of applying these materials as light-harvesting agents in semiconductor sensitized solar cells. PMID:27019713

  7. Nanostructured metal sulfides for energy storage.

    PubMed

    Rui, Xianhong; Tan, Huiteng; Yan, Qingyu

    2014-09-01

    Advanced electrodes with a high energy density at high power are urgently needed for high-performance energy storage devices, including lithium-ion batteries (LIBs) and supercapacitors (SCs), to fulfil the requirements of future electrochemical power sources for applications such as in hybrid electric/plug-in-hybrid (HEV/PHEV) vehicles. Metal sulfides with unique physical and chemical properties, as well as high specific capacity/capacitance, which are typically multiple times higher than that of the carbon/graphite-based materials, are currently studied as promising electrode materials. However, the implementation of these sulfide electrodes in practical applications is hindered by their inferior rate performance and cycling stability. Nanostructures offering the advantages of high surface-to-volume ratios, favourable transport properties, and high freedom for the volume change upon ion insertion/extraction and other reactions, present an opportunity to build next-generation LIBs and SCs. Thus, the development of novel concepts in material research to achieve new nanostructures paves the way for improved electrochemical performance. Herein, we summarize recent advances in nanostructured metal sulfides, such as iron sulfides, copper sulfides, cobalt sulfides, nickel sulfides, manganese sulfides, molybdenum sulfides, tin sulfides, with zero-, one-, two-, and three-dimensional morphologies for LIB and SC applications. In addition, the recently emerged concept of incorporating conductive matrices, especially graphene, with metal sulfide nanomaterials will also be highlighted. Finally, some remarks are made on the challenges and perspectives for the future development of metal sulfide-based LIB and SC devices. PMID:25073046

  8. Selenium Sulfide

    MedlinePlus

    Selenium sulfide comes in a lotion and is usually applied as a shampoo. As a shampoo, selenium sulfide usually is used twice a week for the first ... it is irritating. Rinse off all of the lotion.Do not use this medication on children younger ...

  9. Hydrothermal ore-forming processes in the light of studies in rock- buffered systems: I. Iron-copper-zinc-lead sulfide solubility relations

    USGS Publications Warehouse

    Hemley, J.J.; Cygan, G.L.; Fein, J.B.; Robinson, G.R.; d'Angelo, W. M.

    1992-01-01

    Experimental studies, using cold-seal and extraction vessel techniques, were conducted on Fe, Pb, Zn, and Cu sulfide solubilities in chloride soultions at temperatures from 300?? to 700??C and pressures from 0.5 to 2 kbars. The solutions were buffered in pH by quartz monzonite and the pure potassium feldspar-muscovite-quartz assemblage and in fS2-fO2 largely by the assemblage pyrite-pyrrhotite-magnetite. Solubilities increase with increasing temperature and total chloride, and decrease with increasing pressure. The effect of increasing chloride concentration on solubility reflects primarily a shift to lower pH via the silicate buffer reactions. Similarity in behaviour with respect to the temperature and pressure of Fe, Zn, and Pb sulfide solubilities points to similarity in chloride speciation, and the neutral species appear to be dominant in the high-temperature region. -from Authors

  10. Crystal structure of poly[(μ3-thio­cyanato-κ3 N:S:S)(tri­methyl­phosphine sulfide-κS)copper(I)

    PubMed Central

    Corfield, Peter W. R.

    2014-01-01

    In the title compound, [Cu(NCS)(C3H9PS)]n, the thio­cyanate ions bind the CuI atoms covalently, forming infinite –Cu—SCN—Cu– chains parallel to the a axis. Each CuI atom is also coordinated to a tri­methyl­phosphine sulfide group via a Cu—S bond. Two crystallographically independent chains propagate in opposite directions, and are held together in a ribbon arrangement by long bonds between CuI atoms in the first chain and thio­cyanate S atoms in the second, with Cu—S = 2.621 (1) Å. The geometry around the CuI atoms in the first chain is distorted tetra­hedral, with angles involving the long Cu—S bond much less than ideal, and the S—Cu—N angle between the phosphine sulfide S atom and the thio­cyanate N atom opening out to 133.19 (9)°. Each CuI atom in the second chain appears to be disordered between two positions 0.524 (4) Å apart, with occupancy factors of 0.647 (6) and 0.353 (6). The CuI atom in the major site is in a distorted trigonal–planar configuration, with the S—Cu—N angle between the phosphine sulfide and the thio­cyanate N atom again opened out, to 137.01 (15)°. The CuI atom in the minor site, however, forms in addition a long bond [Cu—S = 2.702 (5) Å] to the phosphine sulfide of the first chain, not the thio­cyanate S atom, to provide a further link between the chains. PMID:25484723

  11. Copper-catalyzed C-H bond direct chalcogenation of aromatic compounds leading to diaryl sulfides, selenides, and diselenides by using elemental sulfur and selenium as chalcogen sources under oxidative conditions.

    PubMed

    Shibahara, Fumitoshi; Kanai, Takafumi; Yamaguchi, Eiji; Kamei, Akika; Yamauchi, Takayuki; Murai, Toshiaki

    2014-01-01

    The reactions of aromatic compounds and elemental chalcogens catalyzed by a copper salt with molecular oxygen as an oxidant were carried out. The reaction of 3-substituted imidazo[1,5-a]pyridines and elemental sulfur in the presence of CuTC (copper(I) thiophenecarboxylate) gave the corresponding bisimidazopyridyl sulfides in good to quantitative yields. The reaction proceeded even under aerobic oxidation conditions. The use of a polar solvent was crucial for the reaction, and DMSO (dimethyl sulfoxide) in particular stimulated the reaction. The reaction could be applied to common aromatic compounds, such as N-methyl indole and dialkyl anilines. The reaction of indole proceeded at the nucleophilic C3 position rather than at the acidic C2 position. In addition, the reaction of dialkyl anilines proceeded with an ortho, para orientation. The reactions of imidazopyridines and elemental selenium under similar conditions gave the corresponding bisimidazopyridyl diselenides along with bisimidazopyridyl monoselenides. The resulting diselenides were readily converted to the corresponding monoselenides with unreacted imidazopyridines under the same conditions. The reaction could be applied to the copolymerization of bifunctional bisimidazopyridines and elemental sulfur to give oligomeric copolymers in quantitative yield. PMID:24347073

  12. Selenium sulfide

    Integrated Risk Information System (IRIS)

    Selenium sulfide ; CASRN 7446 - 34 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  13. Hydrogen sulfide

    Integrated Risk Information System (IRIS)

    Hydrogen sulfide ; 7783 - 06 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  14. Carbonyl sulfide

    Integrated Risk Information System (IRIS)

    Carbonyl sulfide ; CASRN 463 - 58 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  15. Sulfide clean-up of solutions from heavy metal ions

    SciTech Connect

    Kislinskaya, G.E.; Kozachek, N.N.; Krasnova, G.M.; Shenk, N.I.

    1982-09-20

    The object of the present research was to determine the conditions for thorough clean-up of solutions from cadmium or mercury contamination by use of iron sulfide. Results indicated that the shape of the dependence of the degree of extraction of copper with iron sulfide on the pH value is analogous to the curve for cadmium; that is, copper, like cadmium, is precipitated by chemical reaction. In distinction from cadmium and copper, mercury is extracted by iron sulfide both in acid and also in neutral solutions, that is, it is possible to attain a direct ion exchange by reaction. At high pH values, only small amounts of iron go into solution, therefore FeS can be used very rationally for the extraction of both small (about 1 mg/liter), and also of large (about 1 mg/liter) amounts of mercury from solutions, which are nearly neutral. By adding sodium sulfide and a flocculant, one can accelerate the process of mercury precipitation, and also reduce the solution of iron sulfide. In the present case, iron sulfide plays the role of a substrate for the crystallization of mercury sulfide, since in dilute solutions the latter forms poorly filterable colloidal solutions. Thus when one uses fused iron sulfide with addition of sodium sulfide, a high degree of mercury extraction is attained, and the spent sorbent is filtered well.

  16. Metallic sulfide additives for positive electrode material within a secondary electrochemical cell

    DOEpatents

    Walsh, William J.; McPheeters, Charles C.; Yao, Neng-ping; Koura, Kobuyuki

    1976-01-01

    An improved active material for use within the positive electrode of a secondary electrochemical cell includes a mixture of iron disulfide and a sulfide of a polyvalent metal. Various metal sulfides, particularly sulfides of cobalt, nickel, copper, cerium and manganese, are added in minor weight proportion in respect to iron disulfide for improving the electrode performance and reducing current collector requirements.

  17. Dynamic of active microorganisms inhabiting a bioleaching industrial heap of low‐grade copper sulfide ore monitored by real‐time PCR and oligonucleotide prokaryotic acidophile microarray

    PubMed Central

    Remonsellez, Francisco; Galleguillos, Felipe; Moreno‐Paz, Mercedes; Parro, Víctor; Acosta, Mauricio; Demergasso, Cecilia

    2009-01-01

    Summary The bioleaching of metal sulfide has developed into a very important industrial process and understanding the microbial dynamic is key to advancing commercial bioleaching operations. Here we report the first quantitative description of the dynamic of active communities in an industrial bioleaching heap. Acidithiobacillus ferrooxidans was the most abundant during the first part of the leaching cycle, while the abundance of Leptospirillum ferriphilum and Ferroplasma acidiphilum increased with age of the heap. Acidithiobacillus thiooxidans kept constant throughout the leaching cycle, and Firmicutes group showed a low and a patchy distribution in the heap. The Acidiphilium‐like bacteria reached their highest abundance corresponding to the amount of autotrophs. The active microorganisms in the leaching system were determined using two RNA‐based sensitive techniques. In most cases, the 16S rRNA copy numbers of At. ferrooxidans, L. ferriphilum, At. thiooxidans and F. acidiphilum, was concomitant with the DNA copy numbers, whereas Acidiphilium‐like bacteria and some Firmicutes members did not show a clear correlation between 16S rRNA accumulation and DNA copy numbers. However, the prokaryotic acidophile microarray (PAM) analysis showed active members of Alphaproteobacteria in all samples and of Sulfobacillus genus in older ones. Also, new active groups such as Actinobacteria and Acidobacterium genus were detected by PAM. The results suggest that changes during the leaching cycle in chemical and physical conditions, such as pH and Fe3+/Fe2+ ion rate, are primary factors shaping the microbial dynamic in the heap. PMID:21255296

  18. Scientific communications: Re-Os sulfide (bornite, chalcopyrite, and pyrite) systematics of the carbonate-hosted copper deposits at ruby creek, southern brooks range, Alaska

    USGS Publications Warehouse

    Selby, D.; Kelley, K.D.; Hitzman, M.W.; Zieg, J.

    2009-01-01

    New Re-Os data for chalcopyrite, bornite, and pyrite from the carbonate-hosted Cu deposit at Ruby Creek (Bornite), Alaska, show extremely high Re abundances (hundreds of ppb, low ppm) and contain essentially no common Os. The Re-Os data provide the first absolute ages of ore formation for the carbonate-hosted Ruby Creek Cu-(Co) deposit and demonstrate that the Re-Os systematics of pyrite, chalcopyrite, and bornite are unaffected by greenschist metamorphism. The Re-Os data show that the main phase of Cu mineralization pre dominantly occurred at 384 ?? 4.2 Ma, with an earlier phase possibly at ???400 Ma. The Re-Os data are consistent with the observed paragenetic sequence and coincide with zircon U-Pb ages from igneous rocks within the Ambler metallogenic belt, some of which are spatially and genetically associated with regional volcanogenic massive sulfide deposits. The latter may suggest a temporal link between regional magmatism and hydrothermal mineralization in the Ambler district. The utility of bornite and chalcopyrite, in addition to pyrite, contributes to a new understanding of Re-Os geochronology and permits a refinement of the genetic model for the Ruby Creek deposit. ?? 2009 Society of Economices Geologists, Inc.

  19. Effects of spatial and temporal variation of acid-volatile sulfide on the bioavailability of copper and zinc in freshwater sediments

    SciTech Connect

    Besser, J.M.; Ingersoll, C.G.; Giesy, J.P.

    1996-03-01

    Variation in concentrations of acid-volatile sulfide (AVS) in sediments from the upper Clark Fork River of Montana, USA, was associated with differences in bioaccumulation of Cu and Zn and growth of larvae of the midge, Chironomus tentans. Growth of midge larvae was significantly greater and bioaccumulation of Cu was significantly less in surface sections (0--3 cm depth) of sediment cores, which had greater concentrations of AVS and lesser ratios of simultaneously extracted metals to AVS (SEM:AVS ratios) than in subsurface sediments (6--9 cm). Concentrations of AVS were significantly less in sediments incubated with oxic overlying water for 9 weeks than in the same sediments incubated under anoxic conditions. Bioaccumulation of Cu differed significantly between incubation treatments, corresponding to differences in concentrations of AVS and SEM:AVS ratios, although midge growth did not. Bioaccumulation of Zn did not differ significantly between depth strata of sediment cores or between incubation treatments. When results from the two sets of bioassays were combined, bioaccumulation of Cu and Zn, but not growth, was significantly correlated with SEM:AVS ratios and other estimates of bioavailable metal fractions in sediments. Growth of midge larvae was significantly correlated with bioaccumulation of Zn, but not Cu, suggesting that Zn was the greater contributor to the toxicity of these sediments. Assessments of the toxicity of metal-contaminated freshwater sediments should consider the effects of spatial and temporal variation in AVS concentrations on metal bioavailability.

  20. Formation of selenide, sulfide or mixed selenide-sulfide films on metal or metal coated substrates

    DOEpatents

    Eser, Erten; Fields, Shannon

    2012-05-01

    A process and composition for preventing cracking in composite structures comprising a metal coated substrate and a selenide, sulfide or mixed selenide sulfide film. Specifically, cracking is prevented in the coating of molybdenum coated substrates upon which a copper, indium-gallium diselenide (CIGS) film is deposited. Cracking is inhibited by adding a Se passivating amount of oxygen to the Mo and limiting the amount of Se deposited on the Mo coating.

  1. Utilization of reduced graphene oxide/cadmium sulfide-modified carbon cloth for visible-light-prompt photoelectrochemical sensor for copper (II) ions.

    PubMed

    Foo, C Y; Lim, H N; Pandikumar, A; Huang, N M; Ng, Y H

    2016-03-01

    A newly developed CdS/rGO/CC electrode was prepared based on a flexible carbon cloth (CC) substrate with cadmium sulfide (CdS) nanoparticles and reduced graphene oxide (rGO). The CdS was synthesized using an aerosol-assisted chemical vapor deposition (AACVD) method, and the graphene oxide was thermally reduced on the modified electrode surface. The existence of rGO in the CdS-modified electrode increased the photocurrent intensity of the CdS/rGO/CC-modified electrode by three orders of magnitude, compared to that of the CdS/ITO electrode and two orders of magnitude higher than the CdS/CC electrode. A new visible-light-prompt photoelectrochemical sensor was developed based on the competitive binding reaction of Cu(2+) and CdS on the electrode surface. The results showed that the effect of the Cu(2+) on the photocurrent response was concentration-dependent over the linear ranges of 0.1-1.0 μM and 1.0-40.0 μM with a detection limit of 0.05 μM. The results of a selectivity test showed that this modified electrode has a high response toward Cu(2+) compared to other heavy metal ions. The proposed CdS/rGO/CC electrode provided a significantly high potential current compared to other reported values, and could be a practical tool for the fast, sensitive, and selective determination of Cu(2+). PMID:26595899

  2. Platinum metals magmatic sulfide ores.

    PubMed

    Naldrett, A J; Duke, J M

    1980-06-27

    Platinum-group elements (PGE) are mined predominantly from deposits that have formed by the segregation of molten iron-nickel-copper sulfides from silicate magmas. The absolute concentrations of PGE in sulfides from different deposits vary over a range of five orders of magnitude, whereas those of other chalcophile elements vary by factors of only 2 to 100. However, the relative proportions of the different PGE in a given deposit are systematically related to the nature of the parent magma. The absolute and relative concentrations of PGE in magmatic sulfides are explained in terms of the degree of partial melting of mantle peridotite required to produce the parent magma and the processes of batch equilibration and fractional segregation of sulfides. The Republic of South Africa and the U.S.S.R. together possess more than 97 percent of the world PGE reserves, but significant undeveloped resources occur in North America. The Stillwater complex in Montana is perhaps the most important example. PMID:17796685

  3. Temporal and spatial distribution of alteration, mineralization and fluid inclusions in the transitional high-sulfidation epithermal-porphyry copper system at Red Mountain, Arizona

    USGS Publications Warehouse

    Lecumberri-Sanchez, Pilar; Newton, M. Claiborne, III; Westman, Erik C.; Kamilli, Robert J.; Canby, Vertrees M.; Bodnar, Robert J.

    2013-01-01

    Red Mountain, Arizona, is a Laramide porphyry Cu system (PCD) that has experienced only a modest level of erosion compared to most other similar deposits in the southwestern United States. As a result, the upper portion of the magmatic–hydrothermal system, which represents the transition from shallower high-sulfidation epithermal mineralization to deeper porphyry Cu mineralization, is well preserved. Within the Red Mountain system, alteration, mineralization and fluid inclusion assemblages show a systematic distribution in both time and space. Early-potassic alteration (characterized by the minerals biotite and magnetite) is paragenetically earlier than late-potassic alteration (K-feldspar–anhydrite) and both are followed by later phyllic (sericite–pyrite) alteration. Advanced argillic alteration (pyrophyllite–alunite–other clay minerals) is thought to be coeval with or postdate phyllic alteration. Minerals characteristic of advanced argillic alteration are present in the near surface. Phyllic alteration extends to greater depths compared to advanced argillic alteration. Early-potassic and late-potassic alteration are only observed in the deepest part of the system. Considerable overlap of phyllic alteration with both early-potassic and late-potassic alteration zones is observed. The hypogene mineralization contains 0.4–1.2% Cu and is spatially and temporally related to the late-potassic alteration event. Molybdenum concentration is typically In the deepest part of the system, an early generation of low-to-moderate density and salinity liquid + vapor inclusions with opaque daughter minerals is followed in time by halite-bearing inclusions that also contain opaque daughter minerals indicating that an early intermediate-density magmatic fluid evolved to a high-density, high-salinity mineralizing fluid. The increase in density and salinity of fluids with time observed in the deeper parts of the system may be the result of immiscibility (“boiling”) of

  4. Trace element distribution, with a focus on gold, in copper-rich and zinc-rich sulfide chimneys from Brothers submarine volcano, Kermadec arc

    NASA Astrophysics Data System (ADS)

    Berkenbosch, H. A.; de Ronde, C. E.; McNeill, A.; Goemann, K.; Gemmell, J. B.

    2012-12-01

    Brothers volcano is a dacitic volcano located along the Kermadec arc, New Zealand, and hosts the NW Caldera hydrothermal vent field perched on part of the steep caldera walls. The field strikes for ~600 m between depths of 1550 and 1700 m and includes numerous, active, high-temperature (max 302°C) chimneys and even more dead, sulfide-rich spires. Chimney samples collected from Brothers show distinct mineralogical zonation reflecting gradients in oxidation state, temperature, and pH from the inner walls in contact with hydrothermal fluids through to the outer walls in contact with seawater. Minerals deposited from hotter fluids (e.g., chalcopyrite) are located in the interior of the chimneys and are surrounded by an external zone of minerals deposited by cooler fluids (e.g., sulfates, sphalerite). Four chimneys types are identified at Brothers volcano based on the relative proportions of chalcopyrite and sulfate layers, and the presence or absence of anhydrite. Two are Cu-rich, i.e., chalcopyrite-rich and chalcopyrite-bornite-rich chimneys, and two are Zn-rich, i.e., sphalerite-rich and sphalerite-chalcopyrite-rich. Barite and anhydrite are common to both Cu-rich chimney types whereas Zn-rich chimneys contain barite only. The main mineral phases in all the chimneys are anhydrite, barite, chalcopyrite, pyrite/marcasite, and sphalerite. Trace minerals include galena, covellite, tennantite, realgar, chalcocite, bornite, hematite, goethite, Pb-As sulfosalts, and Bi- or Au-tellurides. The vast majority of tellurides are <5 μm in size and they commonly form in bands, cluster in patches, or occur along internal grain boundaries within chalcopyrite. In sulfate layers adjacent to the chalcopyrite zones tellurides can occur as inclusions in anhydrite, barite or pyrite and/or occupy void space within the chimney. The occurrence of specular hematite and Bi- or Au-tellurides associated with chalcopyrite are consistent with magmatic contributions to the NW Caldera vent site

  5. Sulfide chemiluminescence detection

    DOEpatents

    Spurlin, Stanford R.; Yeung, Edward S.

    1985-01-01

    A method of chemiluminescently determining a sulfide which is either hydrogen sulfide or methyl mercaptan by reacting the sulfide with chlorine dioxide at low pressure and under conditions which allow a longer reaction time in emission of a single photon for every two sulfide containing species, and thereafter, chemiluminescently detecting and determining the sulfide. The invention also relates not only to the detection method, but the novel chemical reaction and a specifically designed chemiluminescence detection cell for the reaction.

  6. Sulfide chemiluminescence detection

    DOEpatents

    Spurlin, S.R.; Yeung, E.S.

    1985-11-26

    A method is described for chemiluminescently determining a sulfide which is either hydrogen sulfide or methyl mercaptan by reacting the sulfide with chlorine dioxide at low pressure and under conditions which allow a longer reaction time in emission of a single photon for every two sulfide containing species, and thereafter, chemiluminescently detecting and determining the sulfide. The invention also relates not only to the detection method, but the novel chemical reaction and a specifically designed chemiluminescence detection cell for the reaction. 4 figs.

  7. Cadmium sulfide membranes

    DOEpatents

    Spanhel, Lubomir; Anderson, Marc A.

    1992-07-07

    A method is described for the creation of novel q-effect cadmium sulfide membranes. The membranes are made by first creating a dilute cadmium sulfide colloid in aqueous suspension and then removing the water and excess salts therefrom. The cadmium sulfide membrane thus produced is luminescent at room temperature and may have application in laser fabrication.

  8. Cadmium sulfide membranes

    DOEpatents

    Spanhel, Lubomir; Anderson, Marc A.

    1991-10-22

    A method is described for the creation of novel q-effect cadmium sulfide membranes. The membranes are made by first creating a dilute cadmium sulfide colloid in aqueous suspension and then removing the water and excess salts therefrom. The cadmium sulfide membrane thus produced is luminescent at room temperature and may have application in laser fabrication.

  9. Occurrence model for magmatic sulfide-rich nickel-copper-(platinum-group element) deposits related to mafic and ultramafic dike-sill complexes: Chapter I in Mineral deposit models for resource assessment

    USGS Publications Warehouse

    Schulz, Klaus J.; Woodruff, Laurel G.; Nicholson, Suzanne W.; Seal, Robert R., II; Piatak, Nadine M.; Chandler, Val W.; Mars, John L.

    2014-01-01

    The sulfides in magmatic Ni-Cu deposits generally constitute a small volume of the host rock(s) and tend to be concentrated in the lower parts of the mafic and/or ultramafic bodies, often in physical depressions or areas marking changes in the geometry of the footwall topography. In most deposits, the sulfide mineralization can be divided into disseminated, matrix or net, and massive sulfide, depending on a combination of the sulfide content of the rock and the silicate texture. The major Ni-Cu sulfide mineralogy typically consists of an intergrowth of pyrrhotite (Fe7S8), pentlandite ([Fe, Ni]9S8), and chalcopyrite (FeCuS2). Cobalt, PGE, and gold (Au) are extracted from most magmatic Ni-Cu ores as byproducts, although such elements can have a significant impact on the economics in some deposits, such as the Noril’sk-Talnakh deposits, which produce much of the world’s palladium. In addition, deposits may contain between 1 and 15 percent magnetite associated with the sulfides.

  10. Integrated thin film cadmium sulfide solar cell module

    NASA Technical Reports Server (NTRS)

    Mickelsen, R. A.; Abbott, D. D.

    1971-01-01

    The design, development, fabrication and tests of flexible integrated thin-film cadmium sulfide solar cells and modules are discussed. The development of low cost and high production rate methods for interconnecting cells into large solar arrays is described. Chromium thin films were applied extensively in the deposited cell structures as a means to: (1) achieve high adherence between the cadmium sulfide films and the vacuum-metallized copper substrates, (2) obtain an ohmic contact to the cadmium sulfide films, and (3) improve the adherence of gold films as grids or contact areas.

  11. Pressure leaching las cruces copper ore

    NASA Astrophysics Data System (ADS)

    Berezowsky, R. M.; Xue, T.; Collins, M. J.; Makwana, M.; Barton-Jones, I.; Southgate, M.; Maclean, J. K.

    1999-12-01

    A hydrometallurgical process was developed for treating the Las Cruces massive sulfide-ore deposit located near Seville, Spain. A two-stage countercurrent leach process, consisting of an atmospheric leach and a pressure leach, was developed to effectively leach copper from the copper-bearing minerals and to generate a solution suitable for the subsequent solvent-extraction and copper-electrowinning operations. The results of batch and continuous miniplant tests are presented.

  12. Synthesis and photovoltaic application of coper (I) sulfide nanocrystals

    SciTech Connect

    Wu, Yue; Wadia, Cyrus; Ma, Wanli; Sadtler, Bryce; Alivisatos, A.Paul

    2008-06-24

    We present the rational synthesis of colloidal copper(I) sulfide nanocrystals and demonstrate their application as an active light absorbing component in combination with CdS nanorods to make a solution-processed solar cell with 1.6percent power conversion efficiency on both conventional glass substrates and flexible plastic substrates with stability over a 4 month testing period.

  13. Sulfide Mineralogy and Geochemistry

    NASA Astrophysics Data System (ADS)

    Dilles, John

    2007-02-01

    Reviews in Mineralogy and Geochemistry Series, Volume 61 David J. Vaughan, Editor Geochemical Society and Mineralogical Society of America; ISBN 0-939950-73-1 xiii + 714 pp.; 2006; $40. Sulfide minerals as a class represent important minor rock-forming minerals, but they are generally known as the chief sources of many economic metallic ores. In the past two decades, sulfide research has been extended to include important roles in environmental geology of sulfide weathering and resultant acid mine drainage, as well as in geomicrobiology in which bacteria make use of sulfides for metabolic energy sources. In the latter respect, sulfides played an important role in early evolution of life on Earth and in geochemical cycling of elements in the Earth's crust and hydrosphere.

  14. Platinum metals in magmatic sulfide ores

    USGS Publications Warehouse

    Naldrett, A.J.; Duke, J.M.

    1980-01-01

    Platinum-group elements (PGE) are mined predominantly from deposits that have formed by the segregation of molten iron-nickel-copper sulfides from silicate magmas. The absolute concentrations of PGE in sulfides from different deposits vary over a range of five orders of magnitude, whereas those of other chalcophile elements vary by factors of only 2 to 100. However, the relative proportions of the different PGE in a given deposit are systematically related to the nature of the parent magma. The absolute and relative concentrations of PGE in magmatic sulfides are explained in terms of the degree of partial melting of mantle peridotite required to produce the parent magma and the processes of batch equilibration and fractional segregation of sulfides. The Republic of South Africa and the U.S.S.R. together possess more than 97 percent of the world PGE reserves, but significant undeveloped resources occur in North America. The Stillwater complex in Montana is perhaps the most important example. Copyright ?? 1980 AAAS.

  15. Microbiological Leaching of Metallic Sulfides

    PubMed Central

    Razzell, W. E.; Trussell, P. C.

    1963-01-01

    The percentage of chalcopyrite leached in percolators by Thiobacillus ferrooxidans was dependent on the surface area of the ore but not on the amount. Typical examples of ore leaching, which demonstrate the role of the bacteria, are presented. In stationary fermentations, changes in KH2PO4 concentration above or below 0.1% decreased copper leaching as did reduction in the MgSO4·7H2O and increase in the (NH4)2SO4 concentration. Bacterial leaching of chalcopyrite was more effective than nonbiological leaching with ferric sulfate; ferric sulfate appeared to retard biological leaching, but this effect was likely caused by formation of an insoluble copper-iron complex. Ferrous sulfate and sodium chloride singly accentuated both bacterial and nonbiological leaching of chalcocite but jointly depressed bacterial action. Sodium chloride appeared to block bacterial iron oxidation without interfering with sulfide oxidation. Bacterial leaching of millerite, bornite, and chalcocite was greatest at pH 2.5. The economics of leaching a number of British Columbia ore bodies was discussed. PMID:16349627

  16. The Terminal Oxidase Cytochrome bd Promotes Sulfide-resistant Bacterial Respiration and Growth

    PubMed Central

    Forte, Elena; Borisov, Vitaliy B.; Falabella, Micol; Colaço, Henrique G.; Tinajero-Trejo, Mariana; Poole, Robert K.; Vicente, João B.; Sarti, Paolo; Giuffrè, Alessandro

    2016-01-01

    Hydrogen sulfide (H2S) impairs mitochondrial respiration by potently inhibiting the heme-copper cytochrome c oxidase. Since many prokaryotes, including Escherichia (E.) coli, generate H2S and encounter high H2S levels particularly in the human gut, herein we tested whether bacteria can sustain sulfide-resistant O2-dependent respiration. E. coli has three respiratory oxidases, the cyanide-sensitive heme-copper bo3 enzyme and two bd oxidases much less sensitive to cyanide. Working on the isolated enzymes, we found that, whereas the bo3 oxidase is inhibited by sulfide with half-maximal inhibitory concentration IC50 = 1.1 ± 0.1 μM, under identical experimental conditions both bd oxidases are insensitive to sulfide up to 58 μM. In E. coli respiratory mutants, both O2-consumption and aerobic growth proved to be severely impaired by sulfide when respiration was sustained by the bo3 oxidase alone, but unaffected by ≤200 μM sulfide when either bd enzyme acted as the only terminal oxidase. Accordingly, wild-type E. coli showed sulfide-insensitive respiration and growth under conditions favouring the expression of bd oxidases. In all tested conditions, cyanide mimicked the functional effect of sulfide on bacterial respiration. We conclude that bd oxidases promote sulfide-resistant O2-consumption and growth in E. coli and possibly other bacteria. The impact of this discovery is discussed. PMID:27030302

  17. Biological and Environmental Transformations of Copper-Based Nanomaterials

    PubMed Central

    Wang, Zhongying; Von Dem Bussche, Annette; Kabadi, Pranita K.; Kane, Agnes B.; Hurt, Robert H.

    2013-01-01

    Copper-based nanoparticles are an important class of materials with applications as catalysts, conductive inks, and antimicrobial agents. Environmental and safety issues are particularly important for copper-based nanomaterials because of their potential large-scale use and their high redox activity and toxicity reported from in vitro studies. Elemental nanocopper oxidizes readily upon atmospheric exposure during storage and use, so copper oxides are highly relevant phases to consider in studies of environmental and health impacts. Here we show that copper oxide nanoparticles undergo profound chemical transformations under conditions relevant to living systems and the natural environment. Copper oxide nanoparticle (CuO-NP) dissolution occurs at lysosomal pH (4-5), but not at neutral pH in pure water. Despite the near-neutral pH of cell culture medium, CuO-NPs undergo significant dissolution in media over time scales relevant to toxicity testing due to ligand-assisted ion release, in which amino acid complexation is an important contributor. Electron paramagnetic resonance (EPR) spectroscopy shows that dissolved copper in association with CuO-NPs are the primary redox-active species. CuO-NPs also undergo sulfidation by a dissolution-reprecipitation mechanism, and the new sulfide surfaces act as catalysts for sulfide oxidation. Copper sulfide NPs are found to be much less cytotoxic than CuO NPs, which is consistent with the very low solubility of CuS. Despite this low solubility of CuS, EPR studies show that sulfidated CuO continues to generate some ROS activity due to the release of free copper by H2O2 oxidation during the Fenton-chemistry-based EPR assay. While sulfidation can serve as a natural detoxification process for nanosilver and other chalcophile metals, our results suggest that sulfidation may not fully and permanently detoxify copper in biological or environmental compartments that contain reactive oxygen species. PMID:24032665

  18. Energy and materials flows in the copper industry

    SciTech Connect

    Gaines, L.L.

    1980-12-01

    The copper industry comprises both the primary copper industry, which produces 99.9%-pure copper from copper ore, and the secondary copper industry, which salvages and recycles copper-containing scrap metal to extract pure copper or copper alloys. The United States uses about 2 million tons of copper annually, 60% of it for electrical applications. Demand is expected to increase less than 4% annually for the next 20 years. The primary copper industry is concentrated in the Southwest; Arizona produced 66% of the 1979 total ore output. Primary production uses about 170 x 10/sup 12/ Btu total energy annually (about 100 x 10/sup 6/ Btu/ton pure copper produced from ore). Mining and milling use about 60% of the total consumption, because low-grade ore (0.6% copper) is now being mined. Most copper is extracted by smelting sulfide ores, with concomitant production of sulfur dioxide. Clean air regulations will require smelters to reduce sulfur emissions, necessitating smelting process modifications that could also save 20 x 10/sup 12/ Btu (10 x 10/sup 6/ Btu/ton of copper) in smelting energy. Energy use in secondary copper production averages 20 x 10/sup 6/ Btu/ton of copper. If all copper products were recycled, instead of the 30% now salvaged, the energy conservation potential would be about one-half the total energy consumption of the primary copper industry.

  19. Evidence for extreme partitioning of copper into a magmatic vapor phase

    SciTech Connect

    Lowenstern, J.B.; Mahood, G.A. ); Rivers, M.L.; Sutton, S.R. )

    1991-06-07

    The discovery of copper sulfides in carbon dioxide- and chlorine-bearing bubbles in phenocryst-hosted melt inclusions shows that copper resides in a vapor phase in some shallow magma chambers. Copper is several hundred times more concentrated in magmatic vapor than in coexisting pantellerite melt. The volatile behavior of copper should be considered when modeling the volcanogenic contribution of metals to the atmosphere and may be important in the formation of copper porphyry ore deposits.

  20. Evidence for extreme partitioning of copper into a magmatic vapor phase.

    PubMed

    Lowenstern, J B; Mahood, G A; Rivers, M L; Sutton, S R

    1991-06-01

    The discovery of copper sulfides in carbon dioxide- and chlorine-bearing bubbles in phenocryst-hosted melt inclusions shows that copper resides in a vapor phase in some shallow magma chambers. Copper is several hundred times more concentrated in magmatic vapor than in coexisting pantellerite melt. The volatile behavior of copper should be considered when modeling the volcanogenic contribution of metals to the atmosphere and may be important in the formation of copper porphyry ore deposits. PMID:17772911

  1. Sulfidation of silver nanoparticles

    NASA Astrophysics Data System (ADS)

    Levard, C.; Michel, F. M.; Brown, G. E.

    2010-12-01

    Rapid development of nanotechnologies that exploit the properties of silver nanoparticles (Ag-NPs) raises questions concerning the impact of Ag on the environment. Ag-NPs are currently among the most widely used in the nanotechnology industry and the amount released into the environment is expected to increase along with production (1). When present in geochemical systems, Ag-NPs may undergo a variety of changes due to varying redox, pH, and chemical conditions. Expected changes range from surface modification (e.g., oxidation, sulfidation, chloridation etc.) to complete dissolution and re-precipitation. In this context, the focus of our work is on understanding the behavior of synthetic Ag-NPs with different particle sizes under varying conditions relevant to the environment. Sulfidation of Ag-NPs is of particular interest since it among the processes most likely to occur in aqueous systems, in particular under reducing conditions. Three sizes of Ag-NPs coated with polyvinyl pyrrolidone were produced using the polyol process (2) (7 ±1; 20 ±4, and 40 ±9 nm). Batch solutions containing the different Ag-NPs were subsequently reacted with Na2S solutions of different concentrations. The sulfidation process was followed step-wise for 24 hours and the corrosion products formed were characterized by electron microscopy (TEM/SEM), diffraction (XRD), and photo-electron spectroscopy (XPS). Surface charge (pHPZC) of the products formed during this process was also measured, as were changes in solubility and reactivity. Based on experimental observations we infer that the sulfidation process is the result of dissolution-precipitation and find that: (i) acanthite (Ag2S) is formed as a corrosion product; (ii) Ag-NPs aggregation increased with sulfidation rate; (iii) pHPZC increases with the rate of sulfidation; and (iv) the solubility of the corrosion products formed from sulfidation appears lower than that of non-sulfidated Ag-NPs. We observe size-dependent differences in

  2. SULFIDE METHOD PLUTONIUM SEPARATION

    DOEpatents

    Duffield, R.B.

    1958-08-12

    A process is described for the recovery of plutonium from neutron irradiated uranium solutions. Such a solution is first treated with a soluble sullide, causing precipitation of the plutoniunn and uraniunn values present, along with those impurities which form insoluble sulfides. The precipitate is then treated with a solution of carbonate ions, which will dissolve the uranium and plutonium present while the fission product sulfides remain unaffected. After separation from the residue, this solution may then be treated by any of the usual methods, such as formation of a lanthanum fluoride precipitate, to effect separation of plutoniunn from uranium.

  3. The bioleaching of different sulfide concentrates using thermophilic bacteria

    NASA Astrophysics Data System (ADS)

    Torres, F.; Blázquez, M. L.; González, F.; Ballester, A.; Mier, J. L.

    1995-05-01

    The bioleaching of different mineral sulfide concentrates with thermophilic bacteria (genus Sulfolobus @#@) was studied. Since the use of this type of bacteria in leaching systems involves stirring and the control of temperature, the influence of the type of stirring and the pulp density on dissolution rates was studied in order to ascertain the optimum conditions for metal recovery. At low pulp densities, the dissolution kinetic was favored by pneumatic stirring, but for higher pulp densities, orbital stirring produced the best results. A comparative study of three differential concentrates, one mixed concentrate, and one global concentrate was made. Copper and iron extraction is directly influenced by bacterial activity, while zinc dissolution is basically due to an indirect mechanism that is activated in the presence of copper ions. Galvanic interactions between the different sulfides favors the selective bioleaching of some phases (sphalerite and chalcopyrite) and leads to high metal recovery rates. However, the formation of galvanic couples depends on the type of concentrate.

  4. Zinc sulfide liquefaction catalyst

    DOEpatents

    Garg, Diwakar

    1984-01-01

    A process for the liquefaction of carbonaceous material, such as coal, is set forth wherein coal is liquefied in a catalytic solvent refining reaction wherein an activated zinc sulfide catalyst is utilized which is activated by hydrogenation in a coal derived process solvent in the absence of coal.

  5. Sulfidation kinetics of silver nanoparticles reacted with metal sulfides.

    PubMed

    Thalmann, Basilius; Voegelin, Andreas; Sinnet, Brian; Morgenroth, Eberhard; Kaegi, Ralf

    2014-05-01

    Recent studies have documented that the sulfidation of silver nanoparticles (Ag-NP), possibly released to the environment from consumer products, occurs in anoxic zones of urban wastewater systems and that sulfidized Ag-NP exhibit dramatically reduced toxic effects. However, whether Ag-NP sulfidation also occurs under oxic conditions in the absence of bisulfide has not been addressed, yet. In this study we, therefore, investigated whether metal sulfides that are more resistant toward oxidation than free sulfide, could enable the sulfidation of Ag-NP under oxic conditions. We reacted citrate-stabilized Ag-NP of different sizes (10-100 nm) with freshly precipitated and crystalline CuS and ZnS in oxygenated aqueous suspensions at pH 7.5. The extent of Ag-NP sulfidation was derived from the increase in dissolved Cu(2+) or Zn(2+) over time and linked with results from X-ray absorption spectroscopy (XAS) analysis of selected samples. The sulfidation of Ag-NP followed pseudo first-order kinetics, with rate coefficients increasing with decreasing Ag-NP diameter and increasing metal sulfide concentration and depending on the type (CuS and ZnS) and crystallinity of the reacting metal sulfide. Results from analytical electron microscopy revealed the formation of complex sulfidation patterns that seemed to follow preexisting subgrain boundaries in the pristine Ag-NP. The kinetics of Ag-NP sulfidation observed in this study in combination with reported ZnS and CuS concentrations and predicted Ag-NP concentrations in wastewater and urban surface waters indicate that even under oxic conditions and in the absence of free sulfide, Ag-NP can be transformed into Ag2S within a few hours to days by reaction with metal sulfides. PMID:24678586

  6. Copper transport.

    PubMed

    Linder, M C; Wooten, L; Cerveza, P; Cotton, S; Shulze, R; Lomeli, N

    1998-05-01

    In adult humans, the net absorption of dietary copper is approximately 1 mg/d. Dietary copper joins some 4-5 mg of endogenous copper flowing into the gastrointestinal tract through various digestive juices. Most of this copper returns to the circulation and to the tissues (including liver) that formed them. Much lower amounts of copper flow into and out of other major parts of the body (including heart, skeletal muscle, and brain). Newly absorbed copper is transported to body tissues in two phases, borne primarily by plasma protein carriers (albumin, transcuprein, and ceruloplasmin). In the first phase, copper goes from the intestine to the liver and kidney; in the second phase, copper usually goes from the liver (and perhaps also the kidney) to other organs. Ceruloplasmin plays a role in this second phase. Alternatively, liver copper can also exit via the bile, and in a form that is less easily reabsorbed. Copper is also present in and transported by other body fluids, including those bathing the brain and central nervous system and surrounding the fetus in the amniotic sac. Ceruloplasmin is present in these fluids and may also be involved in copper transport there. The concentrations of copper and ceruloplasmin in milk vary with lactational stage. Parallel changes occur in ceruloplasmin messenger RNA expression in the mammary gland (as determined in pigs). Copper in milk ceruloplasmin appears to be particularly available for absorption, at least in rats. PMID:9587137

  7. Sulfide detoxification in plant mitochondria.

    PubMed

    Birke, Hannah; Hildebrandt, Tatjana M; Wirtz, Markus; Hell, Rüdiger

    2015-01-01

    In contrast to animals, which release the signal molecule sulfide in small amounts from cysteine and its derivates, phototrophic eukaryotes generate sulfide as an essential intermediate of the sulfur assimilation pathway. Additionally, iron-sulfur cluster turnover and cyanide detoxification might contribute to the release of sulfide in mitochondria. However, sulfide is a potent inhibitor of cytochrome c oxidase in mitochondria. Thus, efficient sulfide detoxification mechanisms are required in mitochondria to ensure adequate energy production and consequently survival of the plant cell. Two enzymes have been recently described to catalyze sulfide detoxification in mitochondria of Arabidopsis thaliana, O-acetylserine(thiol)lyase C (OAS-TL C), and the sulfur dioxygenase (SDO) ethylmalonic encephalopathy protein 1 (ETHE1). Biochemical characterization of sulfide producing and consuming enzymes in mitochondria of plants is fundamental to understand the regulatory network that enables mitochondrial sulfide homeostasis under nonstressed and stressed conditions. In this chapter, we provide established protocols to determine the activity of the sulfide releasing enzyme β-cyanoalanine synthase as well as sulfide-consuming enzymes OAS-TL and SDO. Additionally, we describe a reliable and efficient method to purify OAS-TL proteins from plant material. PMID:25747485

  8. Geothermal hydrogen sulfide removal

    SciTech Connect

    Urban, P.

    1981-04-01

    UOP Sulfox technology successfully removed 500 ppM hydrogen sulfide from simulated mixed phase geothermal waters. The Sulfox process involves air oxidation of hydrogen sulfide using a fixed catalyst bed. The catalyst activity remained stable throughout the life of the program. The product stream composition was selected by controlling pH; low pH favored elemental sulfur, while high pH favored water soluble sulfate and thiosulfate. Operation with liquid water present assured full catalytic activity. Dissolved salts reduced catalyst activity somewhat. Application of Sulfox technology to geothermal waters resulted in a straightforward process. There were no requirements for auxiliary processes such as a chemical plant. Application of the process to various types of geothermal waters is discussed and plans for a field test pilot plant and a schedule for commercialization are outlined.

  9. Biotreatment of refinery spent sulfidic caustics

    SciTech Connect

    Sublette, K.L.; Rajganesh, B.; Woolsey, M.; Plato, A.

    1995-12-31

    Caustics are used in petroleum refinering to remove hydrogen sulfide from various hydrocarbon streams. Spent sulfidic caustics from two Conoco refineries have been successfully biotreated on bench and pilot scale, resulting in neutralization and removal of active sulfides. Sulfides were completely oxidized to sulfate by Thiobacillus denitrificans. Microbial oxidation of sulfide produced acid, which at least partially neutralized the caustic.

  10. Alloyed Copper Chalcogenide Nanoplatelets via Partial Cation Exchange Reactions

    PubMed Central

    2014-01-01

    We report the synthesis of alloyed quaternary and quinary nanocrystals based on copper chalcogenides, namely, copper zinc selenide–sulfide (CZSeS), copper tin selenide–sulfide (CTSeS), and copper zinc tin selenide–sulfide (CZTSeS) nanoplatelets (NPLs) (∼20 nm wide) with tunable chemical composition. Our synthesis scheme consisted of two facile steps: i.e., the preparation of copper selenide–sulfide (Cu2–xSeyS1–y) platelet shaped nanocrystals via the colloidal route, followed by an in situ cation exchange reaction. During the latter step, the cation exchange proceeded through a partial replacement of copper ions by zinc or/and tin cations, yielding homogeneously alloyed nanocrystals with platelet shape. Overall, the chemical composition of the alloyed nanocrystals can easily be controlled by the amount of precursors that contain cations of interest (e.g., Zn, Sn) to be incorporated/alloyed. We have also optimized the reaction conditions that allow a complete preservation of the size, morphology, and crystal structure as that of the starting Cu2–xSeyS1–y NPLs. The alloyed NPLs were characterized by optical spectroscopy (UV–vis–NIR) and cyclic voltammetry (CV), which demonstrated tunability of their light absorption characteristics as well as their electrochemical band gaps. PMID:25050455

  11. The cytochrome bd oxidase of Escherichia coli prevents respiratory inhibition by endogenous and exogenous hydrogen sulfide.

    PubMed

    Korshunov, Sergey; Imlay, Karin R C; Imlay, James A

    2016-07-01

    When sulfur compounds are scarce or difficult to process, Escherichia coli adapts by inducing the high-level expression of sulfur-compound importers. If cystine then becomes available, the cystine is rapidly overimported and reduced, leading to a burgeoning pool of intracellular cysteine. Most of the excess cysteine is exported, but some is adventitiously degraded, with the consequent release of sulfide. Sulfide is a potent ligand of copper and heme moieties, raising the prospect that it interferes with enzymes. We observed that when cystine was provided and sulfide levels rose, E. coli became strictly dependent upon cytochrome bd oxidase for continued respiration. Inspection revealed that low-micromolar levels of sulfide inhibited the proton-pumping cytochrome bo oxidase that is regarded as the primary respiratory oxidase. In the absence of the back-up cytochrome bd oxidase, growth failed. Exogenous sulfide elicited the same effect. The potency of sulfide was enhanced when oxygen concentrations were low. Natural oxic-anoxic interfaces are often sulfidic, including the intestinal environment where E. coli dwells. We propose that the sulfide resistance of the cytochrome bd oxidase is a key trait that permits respiration in such habitats. PMID:26991114

  12. Surface reactivity of pyrite and related sulfides

    NASA Astrophysics Data System (ADS)

    Murphy, Riley; Strongin, Daniel R.

    2009-01-01

    Pyrite, FeS 2, commonly referred to as "Fool's gold" is the most common sulfide in the Earth's surface region. Not only is the mineral ubiquitous, but the reactivity of pyrite is of central importance in a devastating environmental issue known as acid mine drainage (AMD) and in beneficial commercial processes such as mineral benefaction, which can range from the desulfurization of coal to the isolation of copper or gold ores. Pyrite has even been postulated to be a key constituent of a prebiotic iron-sulfur world existing at the high pressure and temperature conditions common to hydrothermal vents at the oceanic floor. The development of an atomic level picture of the structure and reactivity of pyrite is paramount to understanding the chemistry of this mineral in these wide-ranging environments. This contribution focuses on research carried out over the past three decades that has used modern surface science tools to understand the reactivity of pyrite surfaces. An understanding of the reactivity of the pyrite surfaces has benefited from studies using a wide range of experimental techniques that range from vacuum-based experiments utilizing electron and photon spectroscopies, and probe microscopy to in situ studies using infra-red spectroscopy. Synchrotron-based techniques that include photoelectron spectroscopy and X-ray absorption spectroscopy have played a large role in both these environments. These techniques have perhaps been the most useful in establishing the structure of the pristine pyrite surface. Related iron sulfides are also briefly introduced in this review including pyrrhotite (Fe xS 1- x) and the dimorph of pyrite, marcasite. The surface reactivity of these sulfides exhibit both similarities and differences to pyrite, and help to bring forward the unique activity of pyrite in both environmentally and technologically important conditions.

  13. Hydrogen sulfide intoxication.

    PubMed

    Guidotti, Tee L

    2015-01-01

    Hydrogen sulfide (H2S) is a hazard primarily in the oil and gas industry, agriculture, sewage and animal waste handling, construction (asphalt operations and disturbing marshy terrain), and other settings where organic material decomposes under reducing conditions, and in geothermal operations. It is an insoluble gas, heavier than air, with a very low odor threshold and high toxicity, driven by concentration more than duration of exposure. Toxicity presents in a unique, reliable, and characteristic toxidrome consisting, in ascending order of exposure, of mucosal irritation, especially of the eye ("gas eye"), olfactory paralysis (not to be confused with olfactory fatigue), sudden but reversible loss of consciousness ("knockdown"), pulmonary edema (with an unusually favorable prognosis), and death (probably with apnea contributing). The risk of chronic neurcognitive changes is controversial, with the best evidence at high exposure levels and after knockdowns, which are frequently accompanied by head injury or oxygen deprivation. Treatment cannot be initiated promptly in the prehospital phase, and currently rests primarily on supportive care, hyperbaric oxygen, and nitrite administration. The mechanism of action for sublethal neurotoxicity and knockdown is clearly not inhibition of cytochrome oxidase c, as generally assumed, although this may play a role in overwhelming exposures. High levels of endogenous sulfide are found in the brain, presumably relating to the function of hydrogen sulfide as a gaseous neurotransmitter and immunomodulator. Prevention requires control of exposure and rigorous training to stop doomed rescue attempts attempted without self-contained breathing apparatus, especially in confined spaces, and in sudden release in the oil and gas sector, which result in multiple avoidable deaths. PMID:26563786

  14. Application of Borehole SIP Technique to Sulfide Mineral Exploration

    NASA Astrophysics Data System (ADS)

    Kim, Changryol; Park, Mi Kyung; Park, Samgyu; Sung, Nak Hoon; Shin, Seung Wook

    2016-04-01

    In the study, SIP (Spectral Induced Polarization) well logging probe system was developed to rapidly locate the metal ore bodies with sulfide minerals in the boreholes. The newly developed SIP logging probe employed the non-polarizable electrodes, consisting of zinc chloride (ZnCl2), sodium chloride (NaCl), gypsum (CaSO4·2H2O), and water (H2O), instead of existing copper electrodes, leading to eliminating the EM coupling effect in the IP surveys as much as possible. In addition, the SIP logging system is designed to make measurements down to maximum 500 meters in depth in the boreholes. The SIP well logging was conducted to examine the applicability of the SIP probe system to the boreholes at the ore mine in Jecheon area, Korea. The boreholes used in the SIP logging are known to have penetrated the metal ore bodies with sulfide minerals from the drilling investigations. The ore mine of the study area is the scarn deposits surrounded by the limestone or lime-silicate rocks in Ordovician period. The results of the SIP well logging have shown that the borehole segments with limestone or lime-silicate rocks yielded the insignificant SIP responses while the borehole segments with sulfide minerals (e.g. pyrite) provided the significant phase shifts of the SIP responses. The borehole segments penetrating the metal ore body, so-called cupola, have shown very high response of the phase shift, due to the high contents of the sulfide mineral pyrite. The phase shifts of the SIP response could be used to estimate the grade of the ore bodies since the higher contents of the sulfide minerals, the higher magnitudes of the phase shifts in the SIP responses. It is, therefore, believed that the borehole SIP technique can be applied to investigate the metal ore bodies with sulfide minerals, and that could be used to estimate the ore grades as a supplementary tool in the future.

  15. Selenium content in sulfide ores from the Chalkidiki peninsula, Greece.

    PubMed

    Nicolaidou, A E

    1998-01-01

    Selenium (Se) was assessed in galena, sphalerite, and pyrite samples. These are components of mixed sulfide ores from the Olympias and Madem Lakkos-Mavres Petres deposits and the Skouries porphyry-copper deposit. We used atomic absorption spectroscopy (AAS) with a hydride generator system. The highest concentration of Se (516 ppm) was found in the fine-grained galena at the -135 level of the Olympias deposits. In the Madem Lakkos-Mavres Petres deposit, the highest concentration of Se (33 ppm) was found in the pyrites of the level 30. The concentration of Se in the arsenopyrites and chalcopyrites is lower than the detection limit of the analytical method (< 100 ppb). The concentrated chalcopyrite from the porphyry copper deposit at Skouries exhibits a significant Se content (average 200 ppm) in contrast to the chalcopyrite from the Olympias and the Madem Lakkos-Mavres Petres. Variations in the Se content of the sulfide minerals studied could be caused by redox-pH and/or temperature conditions, as well as by the difference in crystal structure. The Se found in the areas studied may positively affect the environment. Sulfide minerals are oxidized by microorganisms, infiltrate in the soil-water in the form of selenate or selenite ion, and directly or indirectly influence the human organism. PMID:9726790

  16. Selective Facet Reactivity During Cation Exchange in Cadmium Sulfide Nanorods

    SciTech Connect

    Sadtler, Bryce; Demchenko, Denis; Zheng, Haimei; Hughes, Steven; Merkle, Maxwell; Dahmen, Ulrich; Wang, Lin-Wang; Alivisatos, A. Paul

    2008-12-18

    The partial transformation of ionic nanocrystals through cation exchange has been used to synthesize nanocrystal heterostructures. We demonstrate that the selectivity for cation exchange to take place at different facets of the nanocrystal plays an important role in determining the resulting morphology of the binary heterostructure. In the case of copper I (Cu+) cation exchange in cadmium sulfide (CdS) nanorods, the reaction starts preferentially at the ends of the nanorods such that copper sulfide (Cu2S) grows inwards from either end. The resulting morphology is very different from the striped pattern obtained in our previous studies of silver I (Ag+) exchange in CdS nanorods where non-selective nucleation of silver sulfide (Ag2S) occurs. From interface formation energies calculated for several models of epitaxialconnections between CdS and Cu2S or Ag2S, we infer the relative stability of each interface during the nucleation and growth of Cu2S or Ag2S within the CdS nanorods. The epitaxial connections of Cu2S to the end facets of CdS nanorods minimize the formation energy, making these interfaces stable throughout the exchange reaction. However, as the two end facets of wurtzite CdS nanorods are crystallographically nonequivalent, asymmetric heterostructures can be produced.

  17. Field method for sulfide determination

    SciTech Connect

    Wilson, B L; Schwarser, R R; Chukwuenye, C O

    1982-01-01

    A simple and rapid method was developed for determining the total sulfide concentration in water in the field. Direct measurements were made using a silver/sulfide ion selective electrode in conjunction with a double junction reference electrode connected to an Orion Model 407A/F Specific Ion Meter. The method also made use of a sulfide anti-oxidant buffer (SAOB II) which consists of ascorbic acid, sodium hydroxide, and disodium EDTA. Preweighed sodium sulfide crystals were sealed in air tight plastic volumetric flasks which were used in standardization process in the field. Field standards were prepared by adding SAOB II to the flask containing the sulfide crystals and diluting it to the mark with deionized deaerated water. Serial dilutions of the standards were used to prepare standards of lower concentrations. Concentrations as low as 6 ppB were obtained on lake samples with a reproducibility better than +- 10%.

  18. Sulfide Mineral Surfaces

    SciTech Connect

    Rosso, Kevin M.; Vaughan, David J.

    2006-08-01

    The past twenty years or so have seen dramatic development of the experimental and theoretical tools available to study the surfaces of solids at the molecular (?atomic resolution?) scale. On the experimental side, two areas of development well illustrate these advances. The first concerns the high intensity photon sources associated with synchrotron radiation; these have both greatly improved the surface sensitivity and spatial resolution of already established surface spectroscopic and diffraction methods, and enabled the development of new methods for studying surfaces. The second centers on the scanning probe microscopy (SPM) techniques initially developed in the 1980's with the first scanning tunneling microscope (STM) and atomic force microscope (AFM) experiments. The direct 'observation' of individual atoms at surfaces made possible with these methods has truly revolutionized surface science. On the theoretical side, the availability of high performance computers coupled with advances in computational modeling has provided powerful new tools to complement the advances in experiment. Particularly important have been the quantum mechanics based computational approaches such as density functional theory (DFT), which can now be easily used to calculate the equilibrium crystal structures of solids and surfaces from first principles, and to provide insights into their electronic structure. In this chapter, we review current knowledge of sulfide mineral surfaces, beginning with an overview of the principles relevant to the study of the surfaces of all crystalline solids. This includes the thermodynamics of surfaces, the atomic structure of surfaces (surface crystallography and structural stability, adjustments of atoms at the surface through relaxation or reconstruction, surface defects) and the electronic structure of surfaces. We then discuss examples where specific crystal surfaces have been studied, with the main sulfide minerals organized by structure type

  19. Dispersion strengthened copper

    DOEpatents

    Sheinberg, Haskell; Meek, Thomas T.; Blake, Rodger D.

    1990-01-01

    A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

  20. Dispersion strengthened copper

    DOEpatents

    Sheinberg, Haskell; Meek, Thomas T.; Blake, Rodger D.

    1989-01-01

    A composition of matter comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide, and a method for making this composition of matter.

  1. Electrobioleaching of base metal sulfides

    NASA Astrophysics Data System (ADS)

    Natarajan, K. A.

    1992-01-01

    Bioleaching of base metal sulfides, such as pyrite, chalcopyrite, and sphalerite, under the influence of applied direct current (DC) potentials is discussed. Contributions toward mineral dissolution from three effects, namely, galvanic, applied potential, and microbiological, are analyzed and compared. Sphalerite could be selectively bioleached in the presence of Thiobacillus ferrooxidans under an applied potential of -500 mV (SCE) from mixed sulfides containing sphalerite, pyrite, and chalcopyrite. Bacterial activity and growth were found to be promoted under electrobioleaching conditions. Probable mechanisms involved in the bioleaching of different sulfides under positive and negative applied potentials are discussed.

  2. Copper Metallochaperones

    PubMed Central

    Robinson, Nigel J.; Winge, Dennis R.

    2014-01-01

    The current state of knowledge on how copper metallochaperones support the maturation of cuproproteins is reviewed. Copper is needed within mitochondria to supply the CuA and intramembrane CuB sites of cytochrome oxidase, within the trans-Golgi network to supply secreted cuproproteins and within the cytosol to supply superoxide dismutase 1 (Sod1). Subpopulations of copper-zinc superoxide dismutase also localize to mitochondria, the secretory system, the nucleus and, in plants, the chloroplast, which also requires copper for plastocyanin. Prokaryotic cuproproteins are found in the cell membrane and in the periplasm of gram-negative bacteria. Cu(I) and Cu(II) form tight complexes with organic molecules and drive redox chemistry, which unrestrained would be destructive. Copper metallochaperones assist copper in reaching vital destinations without inflicting damage or becoming trapped in adventitious binding sites. Copper ions are specifically released from copper metallochaperones upon contact with their cognate cuproproteins and metal transfer is thought to proceed by ligand substitution. PMID:20205585

  3. A novel method for improving cerussite sulfidization

    NASA Astrophysics Data System (ADS)

    Feng, Qi-cheng; Wen, Shu-ming; Zhao, Wen-juan; Cao, Qin-bo; Lü, Chao

    2016-06-01

    Evaluation of flotation behavior, solution measurements, and surface analyses were performed to investigate the effects of chloride ion addition on the sulfidization of cerussite in this study. Micro-flotation tests indicate that the addition of chloride ions prior to sulfidization can significantly increase the flotation recovery of cerussite, which is attributed to the formation of more lead sulfide species on the mineral surface. Solution measurement results suggest that the addition of chloride ions prior to sulfidization induces the transformation of more sulfide ions from pulp solution onto the mineral surface by the formation of more lead sulfide species. X-ray diffraction and energy-dispersive spectroscopy indicate that more lead sulfide species form on the mineral surface when chloride ions are added prior to sulfidization. These results demonstrate that the addition of chloride ions prior to sulfidization can significantly improve the sulfidization of cerussite, thereby enhancing the flotation performance.

  4. Prevention of sulfide oxidation in sulfide-rich waste rock

    NASA Astrophysics Data System (ADS)

    Nyström, Elsa; Alakangas, Lena

    2015-04-01

    The ability to reduce sulfide oxidation in waste rock after mine closure is a widely researched area, but to reduce and/or inhibit the oxidation during operation is less common. Sulfide-rich (ca 30 % sulfur) waste rock, partially oxidized, was leached during unsaturated laboratory condition. Trace elements such as As and Sb were relatively high in the waste rock while other sulfide-associated elements such as Cu, Pb and Zn were low compared to common sulfide-rich waste rock. Leaching of unsaturated waste rock lowered the pH, from around six down to two, resulting in continuously increasing element concentrations during the leaching period of 272 days. The concentrations of As (65 mg/L), Cu (6.9 mg/L), Sb (1.2 mg/L), Zn (149 mg/L) and S (43 g/L) were strongly elevated at the end of the leaching period. Different alkaline industrial residues such as slag, lime kiln dust and cement kiln dust were added as solid or as liquid to the waste rock in an attempt to inhibit sulfide oxidation through neo-formed phases on sulfide surfaces in order to decrease the mobility of metals and metalloids over longer time scale. This will result in a lower cost and efforts of measures after mine closure. Results from the experiments will be presented.

  5. Apparatus for use in sulfide chemiluminescence detection

    DOEpatents

    Spurlin, S.R.; Yeung, E.S.

    1987-01-06

    A method is described for chemiluminescently determining a sulfide which is either hydrogen sulfide or methyl mercaptan by reacting the sulfide with chlorine dioxide at low pressure and under conditions which allow a longer reaction time in emission of a single photon for every two sulfide containing species, and thereafter, chemiluminescently detecting and determining the sulfide. The invention also relates not only to the detection method, but the novel chemical reaction and a specifically designed chemiluminescence detection cell for the reaction. 4 figs.

  6. Apparatus for use in sulfide chemiluminescence detection

    DOEpatents

    Spurlin, Stanford R.; Yeung, Edward S.

    1987-01-01

    A method of chemiluminescently determining a sulfide which is either hydrogen sulfide or methyl mercaptan by reacting the sulfide with chlorine dioxide at low pressure and under conditions which allow a longer reaction time in emission of a single photon for every two sulfide containing species, and thereafter, chemiluminescently detecting and determining the sulfide. The invention also relates not only to the detection method, but the novel chemical reaction and a specifically designed chemiluminescence detection cell for the reaction.

  7. Thermoelectric Properties of Lanthanum Sulfide

    NASA Technical Reports Server (NTRS)

    Wood, C.; Lockwood, R.; Parker, J. B.; Zoltan, A.; Zoltan, L. D.; Danielson, L.; Raag, V.

    1987-01-01

    Report describes measurement of Seebeck coefficient, electrical resistivity, thermal conductivity, and Hall effect in gamma-phase lanthanum sulfide with composition of La3-x S4. Results of study, part of search for high-temperature thermoelectric energy-conversion materials, indicate this sulfide behaves like extrinsic semiconductor over temperature range of 300 to 1,400 K, with degenerate carrier concentration controlled by stoichiometric ratio of La to S.

  8. Hydrogen Sulfide Oxidation by Myoglobin.

    PubMed

    Bostelaar, Trever; Vitvitsky, Victor; Kumutima, Jacques; Lewis, Brianne E; Yadav, Pramod K; Brunold, Thomas C; Filipovic, Milos; Lehnert, Nicolai; Stemmler, Timothy L; Banerjee, Ruma

    2016-07-13

    Enzymes in the sulfur network generate the signaling molecule, hydrogen sulfide (H2S), from the amino acids cysteine and homocysteine. Since it is toxic at elevated concentrations, cells are equipped to clear H2S. A canonical sulfide oxidation pathway operates in mitochondria, converting H2S to thiosulfate and sulfate. We have recently discovered the ability of ferric hemoglobin to oxidize sulfide to thiosulfate and iron-bound hydropolysulfides. In this study, we report that myoglobin exhibits a similar capacity for sulfide oxidation. We have trapped and characterized iron-bound sulfur intermediates using cryo-mass spectrometry and X-ray absorption spectroscopy. Further support for the postulated intermediates in the chemically challenging conversion of H2S to thiosulfate and iron-bound catenated sulfur products is provided by EPR and resonance Raman spectroscopy in addition to density functional theory computational results. We speculate that the unusual sensitivity of skeletal muscle cytochrome c oxidase to sulfide poisoning in ethylmalonic encephalopathy, resulting from the deficiency in a mitochondrial sulfide oxidation enzyme, might be due to the concentration of H2S by myoglobin in this tissue. PMID:27310035

  9. New influence factor inducing difficulty in selective flotation separation of Cu-Zn mixed sulfide minerals

    NASA Astrophysics Data System (ADS)

    Deng, Jiu-shuai; Mao, Ying-bo; Wen, Shu-ming; Liu, Jian; Xian, Yong-jun; Feng, Qi-cheng

    2015-02-01

    Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satisfactory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mechanisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions released from the ancient fluids reached 1.02 × 10-6 mol/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 × 10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.

  10. Amorphous molybdenum sulfides as hydrogen evolution catalysts.

    PubMed

    Morales-Guio, Carlos G; Hu, Xile

    2014-08-19

    from simple wet-chemical routes. Electron transport is sometimes slow in the particle catalysts, and an impedance model has been established to identify this slow electron transport. Finally, the amorphous molybdenum sulfide film catalyst has been integrated onto a copper(I) oxide photocathode for photoelectrochemical hydrogen evolution. The conformal catalyst efficiently extracts the excited electrons to give an impressive photocurrent density of -5.7 mA/cm(2) at 0 V vs RHE. The catalyst also confers good stability. PMID:25065612

  11. Ionization levels of doped copper indium sulfide chalcopyrites.

    PubMed

    Tablero, C

    2012-02-01

    The electronic structure of modified chalcopyrite CuInS(2) has been analyzed from first principles within the density functional theory. The host chalcopyrite has been modified by introducing atomic impurities M at substitutional sites in the lattice host with M = C, Si, Ge, Sn, Ti, V, Cr, Fe, Co, Ni, Rh, and Ir. Both substitutions M for In and M for Cu have been analyzed. The gap and ionization energies are obtained as a function of the M-S displacements. It is interesting for both spintronic and optoelectronic applications because it can provide significant information with respect to the pressure effect and the nonradiative recombination. PMID:22239718

  12. Inhaled Hydrogen Sulfide

    PubMed Central

    Volpato, Gian Paolo; Searles, Robert; Yu, Binglan; Scherrer-Crosbie, Marielle; Bloch, Kenneth D.; Ichinose, Fumito; Zapol, Warren M.

    2010-01-01

    Background Breathing hydrogen sulfide (H2S) has been reported to induce a suspended animation–like state with hypothermia and a concomitant metabolic reduction in rodents. However, the impact of H2S breathing on cardiovascular function remains incompletely understood. In this study, the authors investigated the cardiovascular and metabolic effects of inhaled H2S in a murine model. Methods The impact of breathing H2S on cardiovascular function was examined using telemetry and echocardiography in awake mice. The effects of breathing H2S on carbon dioxide production and oxygen consumption were measured at room temperature and in a warmed environment. Results Breathing H2S at 80 parts per million by volume at 27°C ambient temperature for 6 h markedly reduced heart rate, core body temperature, respiratory rate, and physical activity, whereas blood pressure remained unchanged. Echocardiography demonstrated that H2S exposure decreased both heart rate and cardiac output but preserved stroke volume. Breathing H2S for 6 h at 35°C ambient temperature (to prevent hypothermia) decreased heart rate, physical activity, respiratory rate, and cardiac output without altering stroke volume or body temperature. H2S breathing seems to induce bradycardia by depressing sinus node activity. Breathing H2S for 30 min decreased whole body oxygen consumption and carbon dioxide production at either 27° or 35°C ambient temperature. Both parameters returned to baseline levels within 10 min after the cessation of H2S breathing. Conclusions Inhalation of H2S at either 27° or 35°C reversibly depresses cardiovascular function without changing blood pressure in mice. Breathing H2S also induces a rapidly reversible reduction of metabolic rate at either body temperature. PMID:18362598

  13. Sulfur and sulfides in chondrules

    NASA Astrophysics Data System (ADS)

    Marrocchi, Yves; Libourel, Guy

    2013-10-01

    The nature and distribution of sulfides within type I PO, POP and PP chondrules of the carbonaceous chondrite Vigarano (CV3) have been studied by secondary electron microscopy and electron microprobe. They occur predominantly as spheroidal blebs composed entirely of low-Ni iron sulfide (troilite, FeS) or troilite + magnetite but in less abundance in association with metallic Fe-Ni beads in opaque assemblages. Troilites are mainly located within the low-Ca pyroxene outer zone and their amounts increase with the abundance of low-Ca pyroxene within chondrules, suggesting co-crystallization of troilite and low-Ca pyroxene during high-temperature events. We show that sulfur concentration and sulfide occurrence in chondrules obey high temperature sulfur solubility and saturation laws. Depending on the fS2 and fO2 of the surrounding gas and on the melt composition, mainly the FeO content, sulfur dissolved in chondrule melts may eventually reach a concentration limit, the sulfur content at sulfide saturation (SCSS), at which an immiscible iron sulfide liquid separates from the silicate melt. The occurrence of both a silicate melt and an immiscible iron sulfide liquid is further supported by the non-wetting behavior of sulfides on silicate phases in chondrules due to the high interfacial tension between their precursor iron-sulfide liquid droplets and the surrounding silicate melt during the high temperature chondrule-forming event. The evolution of chondrule melts from PO to PP towards more silicic compositions, very likely due to high PSiO(g) of the surrounding nebular gas, induces saturation of FeS at much lower S content in PP than in PO chondrules, leading to the co-crystallization of iron sulfides and low-Ca pyroxenes. Conditions of co-saturation of low-Ca pyroxene and FeS are only achieved in non canonical environments characterized by high partial pressures of sulfur and SiO and redox conditions more oxidizing than IW-3. Fe and S mass balance calculations also

  14. Mechanistic chemical perspective of hydrogen sulfide signaling.

    PubMed

    Nagy, Péter

    2015-01-01

    Hydrogen sulfide is now a well-appreciated master regulator in a diverse array of physiological processes. However, as a consequence of the rapid growth of the area, sulfide biology suffers from an increasing number of controversial observations and interpretations. A better understanding of the underlying molecular pathways of sulfide's actions is key to reconcile controversial issues, which calls for rigorous chemical/biochemical investigations. Protein sulfhydration and coordination/redox chemical interactions of sulfide with heme proteins are the two most extensively studied pathways in sulfide biochemistry. These pathways are important mediators of protein functions, generate bioactive sulfide metabolites, contribute to sulfide storage/trafficking and carry antioxidant functions. In addition, inorganic polysulfides, which are oxidative sulfide metabolites, are increasingly recognized as important players in sulfide biology. This chapter provides an overview of our mechanistic perspective on the reactions that govern (i) sulfide's bioavailability (including the delicate enzyme machineries that orchestrate sulfide production and consumption and the roles of the large sulfide-storing pools as biological buffers), (ii) biological significance and mechanisms of persulfide formation (including the reduction of disulfides, condensation with sulfenic acids, oxidation of thiols with polysulfides and radical-mediated pathways), (iii) coordination and redox chemical interactions of sulfide with heme proteins (including cytochrome c oxidase, hemoglobins, myoglobins and peroxidases), and (iv) the chemistry of polysulfides. PMID:25725513

  15. Photoactive nanocrystals by low-temperature welding of copper sulfide nanoparticles and indium sulfide nanosheets.

    PubMed

    Lim, Hui Min; Tan, Jia Yi; Batabyal, Sudip K; Magdassi, Shlomo; Mhaisalkar, Subodh G; Wong, Lydia H

    2014-12-01

    We successfully utilize the concept of coalescence and room-temperature sintering to prepare morphologically different nanoparticles. n-Type chalcogenide (CuIn5 S8 ) nanocrystals are synthesized at room temperature by simple mixing of oppositely charged precursor nanoparticles. The coalescence of polycation-coated CuS nanoparticles and negatively charged In2 S3 nanoplates is driven by close contact of the particles due to electrostatic interactions. Analysis by X-ray diffraction, transmission electron microscopy (TEM) imaging, and Raman spectroscopy confirms the formation of single-phase CuIn5 S8 without traceable secondary phase. In a photovoltaic device, the use of the coalesced particles yields a power conversion efficiency of 1.8%. PMID:25146714

  16. Cadmium sulfide/copper sulfide heterojunction cell research. Technical progress report, September 1-November 30, 1979

    SciTech Connect

    Anderson, W.W.; Jonath, A.D.

    1980-02-01

    Several all sputter deposited Cu/sub 2/S/CdS cells have been prepared to date with J/sub SC/ approx. = 3 mA/cm/sup 2/ under simulated AM1 illumination. The best AM1 conversion efficiency obtained is 0.6%. This is shown to be typical of sputtered CdS in Cu/sub 2/S/CdS cells investigated to date. The sputtered Cu/sub 2/S appears to be satisfactory for solar cell applications. Presented evidence indicates that the poor conversion efficiency is due to a low-junction electric field intensity on the CdS side of the heterojunction. A multilayer CdS structure has been developed which may allow the tailoring of the junction electric field intensity to a selected high value to obtain high-junction collection efficiency. Other areas of cell development advances included: (1) determination of effect of Cu cones in Cu/sub 2/S on Cu/sub 2/S/CdS cell performance; (2) solution of CdS pinhole problem; and (3) open circuit voltage improvement by heat treatment.

  17. Cadmium sulfide-copper sulfide heterojunction cell research. Quarterly report, September 1-November 30, 1980

    SciTech Connect

    1981-02-01

    Cell yield data for both Cu/sub 2/S/CdS and Cu/sub 2/S/(CdZn)S are reported. The presence of cracking in the n-type films is reported and the influence of composition and substrate material described. Design efforts for an analytical device that is basically a CdS cell on a transparent substrate, and a low cost gridding procedure are reported. A laser scanning system has been developed to detect incipient shorts and shunting in ungridded cells.

  18. Sulfide Capacity in Ladle Slag at Steelmaking Temperatures

    NASA Astrophysics Data System (ADS)

    Allertz, Carl; Sichen, Du

    2015-12-01

    Sulfide capacity measurements were conducted at 1823 K and 1873 K (1550 °C and 1600 °C) for the quaternary Al2O3-CaO-MgO-SiO2 system, for typical compositions used in the ladle in steelmaking. A copper-slag equilibrium was used under controlled oxygen and sulfur potentials. The sulfide capacity is strongly dependent on the composition and it was found to increase with the basic oxides, while it decreases with increase of the acidic components. It was found that CaO is more effective in holding sulfur in the slag compared to MgO when replacing SiO2. For the present slag compositions, Al2O3 and SiO2 behaved similar with respect to sulfur, and no considerable effect could be recorded when replacing one for the other. The sulfide capacity was also found to be strongly dependent on the temperature, increasing with temperature. The present results were compared with industrial data from the ladle, after vacuum treatment, and they were in good agreement.

  19. Sulfide Stability of Planetary Basalts

    NASA Technical Reports Server (NTRS)

    Caiazza, C. M.; Righter, K.; Gibson, E. K., Jr.; Chesley, J. T.; Ruiz, J.

    2004-01-01

    The isotopic system, 187Re 187Os, can be used to determine the role of crust and mantle in magma genesis. In order to apply the system to natural samples, we must understand variations in Re/Os concentrations. It is thought that low [Os] and [Re] in basalts can be attributed to sulfide (FeS) saturation, as Re behaves incompatibly to high degrees of evolution until sulfide saturation occurs [1]. Previous work has shown that lunar basalts are sulfide under-saturated, and mid-ocean ridge, ocean-island and Martian (shergottites) basalts are saturated [2,3]. However, little is known about arc basalts. In this study, basaltic rocks were analyzed across the Trans-Mexican Volcanic Belt.

  20. A Reaction Involving Oxygen and Metal Sulfides.

    ERIC Educational Resources Information Center

    Hill, William D. Jr.

    1986-01-01

    Describes a procedure for oxygen generation by thermal decomposition of potassium chlorate in presence of manganese dioxide, reacted with various sulfides. Provides a table of sample product yields for various sulfides. (JM)

  1. METAL INTERACTIONS AT SULFIDE MINERAL SURFACES: PART 3, METAL AFFINITIES IN SINGLE AND MULTIPLE ION ADSORPTION REACTIONS

    EPA Science Inventory

    Adsorption reactions of both single ions and multiple ion mixtures with sulfide minerals (chalcocite, galena, pyrite, and sphalerite) were investigated in the metal concentration range of 0.0001 to 0.00001 M. Chromium (III), iron (III), barium (II), cadmium (II), copper (II), nic...

  2. Copper isotope variations of copper-rich minerals in seafloor hydrothermal deposits and igneous rocks, measured by a femtosecond LA-MC-ICP-MS

    NASA Astrophysics Data System (ADS)

    Ikehata, K.; Ishibashi, J.; Suzuki, R.; Hirata, T.

    2013-05-01

    In recent years, the copper isotope systematics has seen an increased interest as a potential tool for understanding copper sources and geochemical processes of copper transport and deposition in ore-forming systems. The copper isotope variations of primary and secondary copper-rich minerals from modern (Mariana Trough) and ancient (Besshi-type and Kuroko-type volcanogenic massive sulfide deposits, Japan) seafloor hydrothermal deposits have been analyzed by a femtosecond-pulsed laser ablation multiple collector inductively coupled plasma mass spectrometry (fs-LA-MC-ICP-MS). The δ65Cu (where δ65Cu = [(65Cu/63Cu)sample/ (65Cu/63Cu)NIST-SRM976-1] × 1000) values of copper-rich sulfide minerals of chimney samples from active seafloor hydrothermal deposits are significantly large (δ65Cu = -0.7 to 4.0‰) compared to those of copper-rich minerals in ancient submarine hydrothermal deposits (δ65Cu = -0.3 to 0.4‰; e.g., Ikehata et al., 2011) and in igneous rocks (δ65Cu = -0.3 to 0.3‰; e.g., Ikehata et al., 2012). These large copper isotopic variations in the chimney samples are most likely explained in terms of a redox-controlled isotope fractionation during hydrothermal reworking of copper sulfides below sea floor or alteration of primary hydrothermal copper sulfides by seawater, involving the preferential incorporation of heavy copper isotopes in secondary Cu(II) solutions. These results also suggest that sub-seafloor recrystallization and metamorphic reequilibration may have reduced the original range of copper isotopes. Secondary malachite (δ65Cu = 2.6 to 3.0‰) and native copper (δ65Cu = 1.4 to 1.7‰) in the Besshi-type deposits have heavier copper isotopic values compared to precursor copper-rich minerals. These variations are mainly due to isotope fractionations during redox reactions (weathering) at low temperatures involving the preferential incorporation of heavy copper isotopes in secondary Cu(II) solutions.

  3. 30 CFR 250.604 - Hydrogen sulfide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Hydrogen sulfide. 250.604 Section 250.604...-Workover Operations § 250.604 Hydrogen sulfide. When a well-workover operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined...

  4. 30 CFR 250.808 - Hydrogen sulfide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Hydrogen sulfide. 250.808 Section 250.808 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL... § 250.808 Hydrogen sulfide. Production operations in zones known to contain hydrogen sulfide (H2S) or...

  5. 30 CFR 250.808 - Hydrogen sulfide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Hydrogen sulfide. 250.808 Section 250.808 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL... § 250.808 Hydrogen sulfide. Production operations in zones known to contain hydrogen sulfide (H2S) or...

  6. 30 CFR 250.808 - Hydrogen sulfide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Hydrogen sulfide. 250.808 Section 250.808 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL... § 250.808 Hydrogen sulfide. Production operations in zones known to contain hydrogen sulfide (H2S) or...

  7. 30 CFR 250.504 - Hydrogen sulfide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Hydrogen sulfide. 250.504 Section 250.504...-Completion Operations § 250.504 Hydrogen sulfide. When a well-completion operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined...

  8. 30 CFR 250.808 - Hydrogen sulfide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Hydrogen sulfide. 250.808 Section 250.808... OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Production Safety Systems § 250.808 Hydrogen sulfide. Production operations in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of...

  9. 30 CFR 250.604 - Hydrogen sulfide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Hydrogen sulfide. 250.604 Section 250.604... OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.604 Hydrogen sulfide. When a well-workover operation is conducted in zones known to contain hydrogen sulfide (H2S) or...

  10. 30 CFR 250.504 - Hydrogen sulfide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Hydrogen sulfide. 250.504 Section 250.504... OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations § 250.504 Hydrogen sulfide. When a well-completion operation is conducted in zones known to contain hydrogen sulfide (H2S) or...

  11. 30 CFR 250.490 - Hydrogen sulfide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Hydrogen sulfide. 250.490 Section 250.490 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Hydrogen Sulfide § 250.490 Hydrogen sulfide. (a)...

  12. New data on the Hyrkkoelae native copper mineralization: A natural analogue for the long-term corrosion of copper canisters

    SciTech Connect

    Marcos, N.; Ahonen, L.; Bros, R.; Roos, P.; Suksi, J.; Oversby, V.

    1999-07-01

    The Hyrkkoelae U-Cu mineralization located in southwestern Finland is reassessed with reference to the corrosion mechanisms affecting the stability of native copper and the time-scales of corrosion processes. The mineral assemblage native copper--copper sulfide occurs in open fractures at several depth intervals within granite pegmatites (GP). The surfaces of these open fractures have accumulations of uranophane crystals and other unidentified uranyl compounds. The secondary uranium minerals are mainly distributed around copper sulfide grains. Microscopic intergrowths of copper sulfides and uranyl compounds also have been observed. Groundwater samples were collected from the vicinity of the Cu samples. The hydrogeochemical features of these samples indicate that the present conditions are oxidizing. The minimum age of U(VI) transport and deposition is about 200,000 years. This age is indicated by {sup 234}U/{sup 238}U and {sup 230}Th/{sup 234}U activity ratios of uranophane. The age of the hexavalent uranium precipitation may be somewhat later than the last influxes and/or demobilization of sulfur. The mineral assemblage native copper--copper oxide (cuprite) occurs only at one depth interval within altered granite pegmatite. The fracture surface was coated by smectite. The content of uranium in smectite was 69--75 ppm U. The {sup 234}U/{sup 238}U and {sup 230}Th/{sup 234}U activity ratios of smectite showed that it has been exposed to recent groundwaters (e.g., during the last million years). The pH of the groundwater at this interval was near neutral (6.9). The copper grains present at this fracture surface were as large as 1 mm in diameter and had rims of cuprite of 0.01 to 0.1 mm thick. The smallest grains were totally oxidized.

  13. Sulfide Deposits from the East Pacific Rise Near 21{degrees}N.

    PubMed

    Hekinian, R; Fevrier, M; Bischoff, J L; Picot, P; Shanks, W C

    1980-03-28

    Massive sulfide deposits were discovered from the diving saucer Cyana on the accreting plate boundary region of the East Pacific Rise near 21 degrees N. The deposits form conical and tubular structures lying on a basaltic basement. Mineralogical and geochemical analyses showed two main types of intimately associated products: a polymetallic sulfide-rich material composed of pyrite and marcasite in association, zinc-rich phases, and copper-rich compounds, and an iron-rich oxide and hydroxide material (also called gossan) composed largely of goethite and limonite. Silicate phases such as opaline, silica, iron-silicon clay, and trace amounts of mica and zeolite are encountered in both types of material. Possible mechanisms for the formation of the sulfide deposits on the East Pacific Rise are discussed. PMID:17779603

  14. Sulfide deposits from the east Pacific rise near 21/sup 0/N

    SciTech Connect

    Hekinian, R.; Fevrier, M.; Bischoff, J.L.; Picot, P.; Shanks, W.C.

    1980-03-28

    Massive sulfide deposits were discovered from the diving saucer Cyana on the accreting plate boundary region of the East Pacific Rise near 21/sup 0/N. The deposits form conical and tubular structures lying on a basaltic basement. Mineralogical and geochemical analyses showed two main types of intimately associated products: a polymetallic sulfide-rich material composed of pyrite and marcasite in association, zinc-rich phases, and copper-rich compounds, and an iron-rich oxide and hydroxide material (also called gossan) composed largely of goethite and limonite. Silicate phases such as opaline, silica, iron-silicon clay, and trace amounts of mica and zeolite are encountered in both types of material. Possible mechanisms for the formation of the sulfide deposits on the East Pacific Rise are discussed.

  15. The Effect of Oxygen Potential on the Sulfide Capacity for Slags Containing Multivalent Species

    NASA Astrophysics Data System (ADS)

    Allertz, Carl; Selleby, Malin; Sichen, Du

    2016-06-01

    The dependence of sulfide capacity on the oxygen partial pressure for slags containing multivalent species was investigated experimentally using a slag containing vanadium oxide. Copper-slag equilibration experiments were carried out at 1873 K (1600 °C) in the approximate oxygen partial pressure range 10-15.4 to 10-9 atm. The sulfide capacity was found to be strongly dependent on the oxygen potential in this slag system, increasing with the oxygen partial pressure. The sulfide capacity changed by more than two orders of magnitude over the oxygen partial pressure range. The effect of changing oxygen partial pressure was found to be much greater than the effect of changing slag composition at a fixed oxygen partial pressure.

  16. Copper Imbalances in Ruminants and Humans: Unexpected Common Ground1

    PubMed Central

    Suttle, Neville F.

    2012-01-01

    Ruminants are more vulnerable to copper deficiency than humans because rumen sulfide generation lowers copper availability from forage, increasing the risk of conditions such as swayback in lambs. Molybdenum-rich pastures promote thiomolybdate (TM) synthesis and formation of unabsorbable Cu-TM complexes, turning risk to clinical reality (hypocuprosis). Selection pressures created ruminant species with tolerance of deficiency but vulnerability to copper toxicity in alien environments, such as specific pathogen–free units. By contrast, cases of copper imbalance in humans seemed confined to rare genetic aberrations of copper metabolism. Recent descriptions of human swayback and the exploratory use of TM for the treatment of Wilson’s disease, tumor growth, inflammatory diseases, and Alzheimer’s disease have created unexpected common ground. The incidence of pre–hemolytic copper poisoning in specific pathogen–free lambs was reduced by an infection with Mycobacterium avium that left them more responsive to treatment with TM but vulnerable to long-term copper depletion. Copper requirements in ruminants and humans may need an extra allowance for the “copper cost” of immunity to infection. Residual cuproenzyme inhibition in TM-treated lambs and anomalies in plasma copper composition that appeared to depend on liver copper status raise this question “can chelating capacity be harnessed without inducing copper-deficiency in ruminants or humans?” A model of equilibria between exogenous (TM) and endogenous chelators (e.g., albumin, metallothionein) is used to predict risk of exposure and hypocuprosis; although risk of natural exposure in humans is remote, vulnerability to TM-induced copper deficiency may be high. Biomarkers of TM impact are needed, and copper chaperones for inhibited cuproenzymes are prime candidates. PMID:22983845

  17. High-resolution photoelectron spectroscopy analysis of sulfidation of brass at the rubber/brass interface

    NASA Astrophysics Data System (ADS)

    Ozawa, Kenichi; Kakubo, Takashi; Shimizu, Katsunori; Amino, Naoya; Mase, Kazuhiko; Komatsu, Takayuki

    2013-01-01

    High resolution photoelectron spectroscopy is utilized to investigate the chemical composition at the rubber/brass interface to elucidate the origin of strong adhesion as well as the degradation between rubber and brass. Special attention has been given to copper sulfides formed at the interface during the vulcanization reaction at 170 °C. At least five sulfur-containing species are identified in the adhesive interlayer including crystalline CuS and amorphous CuxS (x ≃ 2). These copper sulfide species are not uniformly distributed within the layer, but there exits the concentration gradation; the concentration of CuxS is high in the region on the rubber side and is diminished in the deeper region, while vice versa for that of CuS. Degradation of the interface adhesive strength by prolonged vulcanization arises from the decrease in the CuxS/CuS ratio accompanying desulfurization of the adhesive layer.

  18. Global transcriptional responses of Acidithiobacillus ferrooxidans Wenelen under different sulfide minerals.

    PubMed

    Latorre, Mauricio; Ehrenfeld, Nicole; Cortés, María Paz; Travisany, Dante; Budinich, Marko; Aravena, Andrés; González, Mauricio; Bobadilla-Fazzini, Roberto A; Parada, Pilar; Maass, Alejandro

    2016-01-01

    In order to provide new information about the adaptation of Acidithiobacillus ferrooxidans during the bioleaching process, the current analysis presents the first report of the global transcriptional response of the native copper mine strain Wenelen (DSM 16786) oxidized under different sulfide minerals. Microarrays were used to measure the response of At. ferrooxidans Wenelen to shifts from iron supplemented liquid cultures (reference state) to the addition of solid substrates enriched in pyrite or chalcopyrite. Genes encoding for energy metabolism showed a similar transcriptional profile for the two sulfide minerals. Interestingly, four operons related to sulfur metabolism were over-expressed during growth on a reduced sulfur source. Genes associated with metal tolerance (RND and ATPases type P) were up-regulated in the presence of pyrite or chalcopyrite. These results suggest that At. ferrooxidans Wenelen presents an efficient transcriptional system developed to respond to environmental conditions, namely the ability to withstand high copper concentrations. PMID:26476161

  19. Seasonal and spatial patterns of metals at a restored copper mine site. I. Stream copper and zinc

    USGS Publications Warehouse

    Bambic, D.G.; Alpers, C.N.; Green, P.G.; Fanelli, E.; Silk, W.K.

    2006-01-01

    Seasonal and spatial variations in metal concentrations and pH were found in a stream at a restored copper mine site located near a massive sulfide deposit in the Foothill copper-zinc belt of the Sierra Nevada, California. At the mouth of the stream, copper concentrations increased and pH decreased with increased streamflow after the onset of winter rain and, unexpectedly, reached extreme values 1 or 2 months after peaks in the seasonal hydrographs. In contrast, aqueous zinc and sulfate concentrations were highest during low-flow periods. Spatial variation was assessed in 400 m of reach encompassing an acidic, metal-laden seep. At this seep, pH remained low (2-3) throughout the year, and copper concentrations were highest. In contrast, the zinc concentrations increased with downstream distance. These spatial patterns were caused by immobilization of copper by hydrous ferric oxides in benthic sediments, coupled with increasing downstream supply of zinc from groundwater seepage.

  20. Mechanism of Mineral Phase Reconstruction for Improving the Beneficiation of Copper and Iron from Copper Slag

    NASA Astrophysics Data System (ADS)

    Guo, Zhengqi; Zhu, Deqing; Pan, Jan; Zhang, Feng

    2016-08-01

    To maximize the recovery of iron and copper from copper slag, the modification process by adding a compound additive (a mixture of hematite, pyrite and manganous oxide) and optimizing the cooling of the slag was studied. The phase reconstruction mechanism of the slag modification process was revealed by thermodynamic calculations, x-ray diffraction, optical microscopy and scanning electron microscopy. The results show that the synergy between the burnt lime and the compound additive promotes the generation of target minerals, such as magnetite and copper matte. In addition, the multifunctional compound additive is able to improve the fluidity of the molten slag, which facilitates the coalescence and growth of fine particles of the target minerals. As a result, the percentage of iron distributed in the form of magnetite increased from 32.9% to 65.1%, and that of the copper exiting in the form of metallic copper and copper sulfide simultaneously increased from 80.0% to 90.3%. Meanwhile, the grains of the target minerals in the modified slag grew markedly to a mean size of over 50 μm after slow cooling. Ultimately, the beneficiation efficiency of copper and iron was improved because of the ease with which the target minerals could be liberated.

  1. SULFIDE PRECIPITATION OF HEAVY METALS

    EPA Science Inventory

    The research program was initiated with the objective of evaluating a new process, the sulfide precipitation of heavy metals from industrial wastewaters. The process was expected to effect a more complete removal of heavy metals than conventional lime processing because of the mu...

  2. p-Chlorophenyl methyl sulfide

    Integrated Risk Information System (IRIS)

    p - Chlorophenyl methyl sulfide ; CASRN 123 - 09 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for N

  3. Transition metal sulfide loaded catalyst

    DOEpatents

    Maroni, Victor A.; Iton, Lennox E.; Pasterczyk, James W.; Winterer, Markus; Krause, Theodore R.

    1994-01-01

    A zeolite based catalyst for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C.sub.2 + hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  4. Copper cyanide

    Integrated Risk Information System (IRIS)

    Copper cyanide ; CASRN 544 - 92 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  5. Production of sulfur gases and carbon dioxide by synthetic weathering of crushed drill cores from the Santa Cruz porphyry copper deposit near Casa Grande, Pinal County, Arizona

    USGS Publications Warehouse

    Hinkle, M.E.; Ryder, J.L.; Sutley, S.J.; Botinelly, T.

    1990-01-01

    Samples of ground drill cores from the southern part of the Santa Cruz porphyry copper deposit, Casa Grande, Arizona, were oxidized in simulated weathering experiments. The samples were also separated into various mineral fractions and analyzed for contents of metals and sulfide minerals. The principal sulfide mineral present was pyrite. Gases produced in the weathering experiments were measured by gas chromatography. Carbon dioxide, oxygen, carbonyl sulfide, sulfur dioxide and carbon disulfide were found in the gases; no hydrogen sulfide, organic sulfides, or mercaptans were detected. Oxygen concentration was very important for production of the volatiles measured; in general, oxygen concentration was more important to gas production than were metallic element content, sulfide mineral content, or mineral fraction (oxide or sulfide) of the sample. The various volatile species also appeared to be interactive; some of the volatiles measured may have been formed through gas reactions. ?? 1990.

  6. Microstructural investigation of copper corrosion: Influence of humidity

    NASA Astrophysics Data System (ADS)

    Campin, Michael J.

    2003-10-01

    Copper is a critical material in electrical components and is subject to atmospheric corrosion. This study characterized the corrosion products formed when copper is exposed to environments containing activated oxygen species or sulfur containing species. Investigation of the oxides formed when copper is exposed to an electron-cyclotron resonance (ECR) O2 plasma has revealed the presence of both Cu2O and CuO. In addition, it was found that the presence of CuO on copper prevents sulfidation. Particular emphasis is placed on the product formed when Cu is exposed to a dilute (50--200 ppb) H2S atmosphere at low (0.5%) to high (80%) relative humidity (RH). An important observation was that the Cu2S growth rate is significantly higher for sulfides formed at low RH compared to high RH. In addition, it is found that for both low and high RH sulfidation, copper reacts to form the low chalcocite phase (Cu2S) as identified by X-ray and electron diffraction. Cross-section and plan-view TEM revealed that the Cu2S grains formed at high RH are 20--50 nm in size with a large amount of porosity, whereas the grains formed at low RH are 75--150+ nm and appear to undergo grain growth with little porosity. Finally, numerical modeling of an ideal diffusion process is used to demonstrate that point like sources can result in behavior similar to that observed for the rate of sulfidation at high RH.

  7. Dispersion strengthened copper

    DOEpatents

    Sheinberg, H.; Meek, T.T.; Blake, R.D.

    1990-01-09

    A composition of matter is described which is comprised of copper and particles which are dispersed throughout the copper, where the particles are comprised of copper oxide and copper having a coating of copper oxide. A method for making this composition of matter is also described. This invention relates to the art of powder metallurgy and, more particularly, it relates to dispersion strengthened metals.

  8. COPPER AND BRAIN FUNCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing evidence shows that brain development and function are impaired when the brain is deprived of copper either through dietary copper deficiency or through genetic defects in copper transport. A number of copper-dependent enzymes whose activities are lowered by copper deprivation form the ba...

  9. Marine diagenesis of hydrothermal sulfide

    SciTech Connect

    Moammar, M.O.

    1985-01-01

    An attempt is made to discuss the artificial and natural oxidation and hydrolysis of hydrothermal sulfide upon interaction with normal seawater. Synthetic and natural ferrosphalerite particles used in kinetic oxidation and hydrolysis studies in seawater develop dense, crystalline coatings consisting of ordered and ferrimagnetic delta-(Fe, Zn)OOH. Due to the formation of this reactive diffusion barrier, the release of Zn into solution decreases rapidly, and sulfide oxidation is reduced to a low rate determined by the diffusion of oxygen through the oxyhydroxide film. This also acts as an efficient solvent for ions such as Zn/sup 2 +/, Ca/sup 2 +/, and possibly Cd/sup 2 +/, which contribute to the stabilization of the delta-FeOOH structure. The oxidation of sulfide occurs in many seafloor spreading areas, such as 21/sup 0/N on the East Pacific Ridge. In these areas the old surface of the sulfide chimneys are found to be covered by an orange stain, and sediment near the base of nonactive vents is also found to consist of what has been referred to as amorphous iron oxide and hydroxide. This thesis also discusses the exceedingly low solubility of zinc in seawater, from delta-(Fe, Zn)OOH and the analogous phase (zinc-ferrihydroxide) and the zinc exchange minerals, 10-A manganate and montmorillonite. The concentrations of all four are of the same magnitude (16, 36.4, and 12 nM, respectively) as the zinc concentration in deep ocean water (approx. 10 nM), which suggests that manganates and montmorillonite with iron oxyhydroxides control zinc concentration in the deep ocean.

  10. Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, September 1--November 30, 1993

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Flytzani-Stephanopoulos, M.; Li Li

    1994-03-01

    The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}C. Such high temperatures will be required for the new generation of gas turbines (inlet >750{degree}C) in Integrated Gasification Combined Cycle (IGCC) systems. The effect of pre-reduction on the performance of the sorbents as well as the rate of different reactions occurring in cyclic sulfidation/regeneration, were studied in a thermogravimetric analyzer (TGA). Sulfidation was conducted with and without H{sub 2} and H{sub 2}O, and with and without pre-reduction in H{sub 2} or H{sub 2}/H{sub 2}O. The results of these tests indicate that reduction and regeneration of both sorbents occurs rapidly. Sulfidation of CuCr{sub 2}O{sub 4}, in H{sub 2}O-free and H{sub 2}-/H{sub 2}O-free gas indicates the possible sulfidation of both copper and chromium. Small quantities of SO{sub 2}, were released during sulfidation suggesting the possible oxidation of H{sub 2}S by the sorbent. Regeneration of the CuCr{sub 2}O{sub 4} was complete while regeneration of the CuO-CeO{sub 2} indicated possible limited sulfate formation.

  11. Sulfide-Driven Microbial Electrosynthesis

    SciTech Connect

    Gong, YM; Ebrahim, A; Feist, AM; Embree, M; Zhang, T; Lovley, D; Zengler, K

    2013-01-01

    Microbial electrosynthesis, the conversion of carbon dioxide to organic molecules using electricity, has recently been demonstrated for acetogenic microorganisms, such as Sporomusa ovata. The energy for reduction of carbon dioxide originates from the hydrolysis of water on the anode, requiring a sufficiently low potential. Here we evaluate the use of sulfide as an electron source for microbial electrosynthesis. Abiotically oxidation of sulfide on the anode yields two electrons. The oxidation product, elemental sulfur, can be further oxidized to sulfate by Desulfobulbus propionicus, generating six additional electrons in the process. The eight electrons generated from the combined abiotic and biotic steps were used to reduce carbon dioxide to acetate on a graphite cathode by Sporomusa ovata at a rate of 24.8 mmol/day.m(2). Using a strain of Desulfuromonas as biocatalyst on the anode resulted in an acetate production rate of 49.9 mmol/day.m(2), with a Coulombic efficiency of over 90%. These results demonstrate that sulfide can serve effectively as an alternative electron donor for microbial electrosynthesis.

  12. Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, December 1, 1991--February 29, 1992

    SciTech Connect

    Abbasian, J.; Hill, A.H.; Wangerow, J.R.; Flytzani-Stephanopoulos, M.; Bo, L.; Patel, C.

    1992-08-01

    The objective of this investigation is to evaluate several novel copper-based binary oxides for their suitability as regenerable sorbents for hot gas cleanup application in the temperature range of 650{degrees} to 850{degrees}C. To achieve this objective, several novel copper-based binary oxide sorbents will be prepared. Experimental tests will be conducted at ambient pressure to determine the stability, sulfidation capacity, regenerability, and sulfidation kinetics of the novel sorbents. Tests will also be conducted at high pressure for the determination of the sulfidation reactivity, regenerability, and durability of the sorbents. The attrition characteristics of the sorbents will also be determined.

  13. Synthesis, characterization, and reactivity of sulfided hexanuclear molybdenum cluster compounds

    SciTech Connect

    Spink, D.

    1990-09-21

    Hexanuclear molybdenum clusters with mixed chloride and sulfide bridging ligands were prepared by reacting {alpha}-MoCl{sub 2} with sodium hydrosulfide in the presence of sodium butoxide. The resulting species, Mo{sub 6}Cl{sub (8-x)}S{sub x}{center dot}npy(x {congruent} 3.6, n {congruent} 4, py = pyridine), was pyrophoric and insoluble. The mixed sulfide chloride cluster species Mo{sub 6}S{sub 4}Cl{sub 4}{center dot}6OPEt{sub 3} and Mo{sub 6}S{sub {approximately}5}Cl{sub {approximately}3}{center dot}6PEt{sub 3} and Mo{sub 6}S{sub 8}{center dot}6PEt{sub 3} were isolated and characterized. Phosphorus-31 nuclear magnetic resonance, electron paramagnetic resonance, and UV/visible spectra were obtained for each fraction. The completely sulfided cluster, Mo{sub 6}S{sub 8}{center dot}6PEt{sub 3}, was prepared similarly and used in various experiments as a possible precursor to Chevrel phase materials of the type Mo{sub 6}S{sub 8}or M{sub n}Mo{sub 6}S{sub 8}. With the goal of removing all of the triethylphosphine ligands, Mo{sub 6}S{sub 8}{center dot}6PEt{sub 3} was reacted with the transition metal carbonyls molybdenum hexacarbonyl and dicobalt octacarbonyl. Reaction on the molecular sulfide cluster with copper(I) chloride in toluene gave a completely insoluble product. The reaction of Mo{sub 6}S{sub 8}{center dot}6PEt{sub 3} with propylene sulfide gave a product whose infrared spectra showed only very weak peaks associated with coordinated triethylphosphine. The elemental analysis of this product fit the formula Mo{sub 6}S{sub 8}{center dot}5SPEt{sub 3}. Reactivity of the outer ligands of the Mo{sub 6}S{sub 8}{center dot}npy and Mo{sub 6}S{sub 8}{center dot}(6{minus}x)PrNH{sub x} clusters were investigated. Crystalline Mo{sub 6}S{sub 8}{center dot}6THT was recovered from the reaction of the n-propylamine derivative with THT. A crystal structure determination was done. 87 refs., 12 fig., 15 tabs.

  14. 30 CFR 250.504 - Hydrogen sulfide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Hydrogen sulfide. 250.504 Section 250.504... § 250.504 Hydrogen sulfide. When a well-completion operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined in § 250.490 of...

  15. 30 CFR 250.604 - Hydrogen sulfide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Hydrogen sulfide. 250.604 Section 250.604... § 250.604 Hydrogen sulfide. When a well-workover operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined in § 250.490 of...

  16. 30 CFR 250.504 - Hydrogen sulfide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Hydrogen sulfide. 250.504 Section 250.504... § 250.504 Hydrogen sulfide. When a well-completion operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined in § 250.490 of...

  17. 30 CFR 250.604 - Hydrogen sulfide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Hydrogen sulfide. 250.604 Section 250.604... § 250.604 Hydrogen sulfide. When a well-workover operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined in § 250.490 of...

  18. 30 CFR 250.604 - Hydrogen sulfide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Hydrogen sulfide. 250.604 Section 250.604... § 250.604 Hydrogen sulfide. When a well-workover operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined in § 250.490 of...

  19. 30 CFR 250.504 - Hydrogen sulfide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Hydrogen sulfide. 250.504 Section 250.504... § 250.504 Hydrogen sulfide. When a well-completion operation is conducted in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S is unknown (as defined in § 250.490 of...

  20. Rapid Synthesis of Nonstoichiometric Lanthanum Sulfide

    NASA Technical Reports Server (NTRS)

    Matsuda, S.; Shapiro, E.; Danielson, L.; Hardister, H.

    1987-01-01

    New process relatively fast and simple. Improved method of synthesizing nonstoichiometric lanthanum sulfide faster and simpler. Product purer because some of prior sources of contamination eliminated.

  1. Molybdenum sulfide/carbide catalysts

    DOEpatents

    Alonso, Gabriel; Chianelli, Russell R.; Fuentes, Sergio; Torres, Brenda

    2007-05-29

    The present invention provides methods of synthesizing molybdenum disulfide (MoS.sub.2) and carbon-containing molybdenum disulfide (MoS.sub.2-xC.sub.x) catalysts that exhibit improved catalytic activity for hydrotreating reactions involving hydrodesulfurization, hydrodenitrogenation, and hydrogenation. The present invention also concerns the resulting catalysts. Furthermore, the invention concerns the promotion of these catalysts with Co, Ni, Fe, and/or Ru sulfides to create catalysts with greater activity, for hydrotreating reactions, than conventional catalysts such as cobalt molybdate on alumina support.

  2. Preparation of amorphous sulfide sieves

    DOEpatents

    Siadati, Mohammad H.; Alonso, Gabriel; Chianelli, Russell R.

    2006-11-07

    The present invention involves methods and compositions for synthesizing catalysts/porous materials. In some embodiments, the resulting materials are amorphous sulfide sieves that can be mass-produced for a variety of uses. In some embodiments, methods of the invention concern any suitable precursor (such as thiomolybdate salt) that is exposed to a high pressure pre-compaction, if need be. For instance, in some cases the final bulk shape (but highly porous) may be same as the original bulk shape. The compacted/uncompacted precursor is then subjected to an open-flow hot isostatic pressing, which causes the precursor to decompose and convert to a highly porous material/catalyst.

  3. Synthesis and Optical Properties of Sulfide Nanoparticles Prepared in Dimethylsulfoxide

    SciTech Connect

    Li, Yuebin; Ma, Lun; Zhang, Xing; Joly, Alan G.; Liu, Zuli; Chen, Wei

    2008-11-01

    Many methods have been reported for the formation of sulfide nanoparticles by the reaction of metallic salts with sulfide chemical sources in aqueous solutions or organic solvents. Here, we report the formation of sulfide nanoparticles in dimethylsulfoxide (DMSO) by boiling metallic salts without sulfide sources. The sulfide sources are generated from the boiling of DMSO and react with metallic salts to form sulfide nanoparticles. In this method DMSO functions as a solvent and a sulfide source as well as a stabilizer for the formation of the nanoparticles. The recipe is simple and economical making sulfide nanoparticles formed in this way readily available for many potential applications.

  4. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Provisions § 425.03 Sulfide analytical methods and applicability. (a) The potassium ferricyanide titration... the potassium ferricyanide titration method for the determination of sulfide in wastewaters...

  5. Response of sulfide:quinone oxidoreductase to sulfide exposure in the echiuran worm Urechis unicinctus.

    PubMed

    Ma, Yu-Bin; Zhang, Zhi-Feng; Shao, Ming-Yu; Kang, Kyoung-Ho; Shi, Xiao-Li; Dong, Ying-Ping; Li, Jin-Long

    2012-04-01

    Sulfide is a natural, widely distributed, poisonous substance, and sulfide:quinone oxidoreductase (SQR) is responsible for the initial oxidation of sulfide in mitochondria. In this study, we examined the response of SQR to sulfide exposure (25, 50, and 150 μM) at mRNA, protein, and enzyme activity levels in the body wall and hindgut of the echiuran worm Urechis unicinctus, a benthic organism living in marine sediments. The results revealed SQR mRNA expression during sulfide exposure in the body wall and hindgut increased in a time- and concentration-dependent manner that increased significantly at 12 h and continuously increased with time. At the protein level, SQR expression in the two tissues showed a time-dependent relationship that increased significantly at 12 h in 50 μM sulfide and 6 h in 150 μM, and then continued to increase with time while no significant increase appeared after 25 μM sulfide exposure. SQR enzyme activity in both tissues increased significantly in a time-dependent manner after 50 μM sulfide exposure. We concluded that SQR expression could be induced by sulfide exposure and that the two tissues studied have dissimilar sulfide metabolic patterns. A U. unicinctus sulfide-induced detoxification mechanism was also discussed. PMID:21997848

  6. Variation in sulfide tolerance of photosystem II in phylogenetically diverse cyanobacteria from sulfidic habitats

    NASA Technical Reports Server (NTRS)

    Miller, Scott R.; Bebout, Brad M.

    2004-01-01

    Physiological and molecular phylogenetic approaches were used to investigate variation among 12 cyanobacterial strains in their tolerance of sulfide, an inhibitor of oxygenic photosynthesis. Cyanobacteria from sulfidic habitats were found to be phylogenetically diverse and exhibited an approximately 50-fold variation in photosystem II performance in the presence of sulfide. Whereas the degree of tolerance was positively correlated with sulfide levels in the environment, a strain's phenotype could not be predicted from the tolerance of its closest relatives. These observations suggest that sulfide tolerance is a dynamic trait primarily shaped by environmental variation. Despite differences in absolute tolerance, similarities among strains in the effects of sulfide on chlorophyll fluorescence induction indicated a common mode of toxicity. Based on similarities with treatments known to disrupt the oxygen-evolving complex, it was concluded that sulfide toxicity resulted from inhibition of the donor side of photosystem II.

  7. Variation in Sulfide Tolerance of Photosystem II in Phylogenetically Diverse Cyanobacteria from Sulfidic Habitats

    PubMed Central

    Miller, Scott R.; Bebout, Brad M.

    2004-01-01

    Physiological and molecular phylogenetic approaches were used to investigate variation among 12 cyanobacterial strains in their tolerance of sulfide, an inhibitor of oxygenic photosynthesis. Cyanobacteria from sulfidic habitats were found to be phylogenetically diverse and exhibited an approximately 50-fold variation in photosystem II performance in the presence of sulfide. Whereas the degree of tolerance was positively correlated with sulfide levels in the environment, a strain's phenotype could not be predicted from the tolerance of its closest relatives. These observations suggest that sulfide tolerance is a dynamic trait primarily shaped by environmental variation. Despite differences in absolute tolerance, similarities among strains in the effects of sulfide on chlorophyll fluorescence induction indicated a common mode of toxicity. Based on similarities with treatments known to disrupt the oxygen-evolving complex, it was concluded that sulfide toxicity resulted from inhibition of the donor side of photosystem II. PMID:14766549

  8. 30 CFR 250.808 - Hydrogen sulfide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Hydrogen sulfide. 250.808 Section 250.808 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE... Safety Systems § 250.808 Hydrogen sulfide. Production operations in zones known to contain...

  9. Catalyst and process for oxidizing hydrogen sulfide

    SciTech Connect

    Hass, R.H.; Fullerton; Ward, J.W.; Yorba, L.

    1984-04-24

    Catalysts comprising bismuth and vanadium components are highly active and stable, especially in the presence of water vapor, for oxidizing hydrogen sulfide to sulfur or SO/sub 2/. Such catalysts have been found to be especially active for the conversion of hydrogen sulfide to sulfur by reaction with oxygen or SO/sub 2/.

  10. New biologically active hydrogen sulfide donors.

    PubMed

    Roger, Thomas; Raynaud, Francoise; Bouillaud, Frédéric; Ransy, Céline; Simonet, Serge; Crespo, Christine; Bourguignon, Marie-Pierre; Villeneuve, Nicole; Vilaine, Jean-Paul; Artaud, Isabelle; Galardon, Erwan

    2013-11-25

    Generous donors: The dithioperoxyanhydrides (CH3 COS)2 , (PhCOS)2 , CH3 COSSCO2 Me and PhCOSSCO2 Me act as thiol-activated hydrogen sulfide donors in aqueous buffer solution. The most efficient donor (CH3 COS)2 can induce a biological response in cells, and advantageously replace hydrogen sulfide in ex vivo vascular studies. PMID:24115650