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Sample records for cu zn complexes

  1. Complex impedance spectra of chip inductor using Li-Zn-Cu-Mn ferrite

    International Nuclear Information System (INIS)

    Nakamura, Tatsuya; Naoe, Masayuki; Yamada, Yoshihiro

    2006-01-01

    A multi-layer chip inductor (MCI) was fabricated using polycrystalline Li-Zn-Cu-Mn ferrite and the green-sheet technique, and its complex impedance spectrum was evaluated with the help of numerical calculations. The complex impedance spectra of the MCI component using Ni-Zn-Cu ferrite, which have been widely used for this application, were very sensitive to the residual stress and deviated much from the calculated values; however, it was found that the complex impedance spectrum of the MCI component using Li-Zn-Cu-Mn ferrite is quite well reproduced by calculation, where the complex permittivity and permeability of the polycrystalline ferrite as well as the MCI dimensions, were used. It implied that the magneto-striction effect was negligible in case of MCI using Li-Zn-Cu-Mn ferrite, and that the difference was related to magneto-strictive coefficient of the polycrystalline ferrite. Consequently, utilization of Li-Zn-Cu-Mn ferrite enabled us to easily design the complex impedance of MCI component

  2. Neuroprotective Effects and Mechanisms of Curcumin–Cu(II and –Zn(II Complexes Systems and Their Pharmacological Implications

    Directory of Open Access Journals (Sweden)

    Fa-Shun Yan

    2017-12-01

    Full Text Available Alzheimer’s disease (AD is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa, is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated. Therefore, the present study was designed to investigate the protective effects of the complexes of curcumin with Cu(II or Zn(II on hydrogen peroxide (H2O2-induced injury and the underlying molecular mechanisms. The use of rat pheochromocytoma (PC12 cells, a widely used neuronal cell model system, was adopted. It was revealed that curcumin–Cu(II complexes systems possessed enhanced O2·–-scavenging activities compared to unchelated curcumin. In comparison with unchelated curcumin, the protective effects of curcumin–Cu(II complexes systems were stronger than curcumin–Zn(II system. Curcumin–Cu(II or –Zn(II complexes systems significantly enhanced the superoxide dismutase, catalase, and glutathione peroxidase activities and attenuated the increase of malondialdehyde levels and caspase-3 and caspase-9 activities, in a dose-dependent manner. The curcumin–Cu(II complex system with a 2:1 ratio exhibited the most significant effect. Further mechanistic study demonstrated that curcumin–Cu(II or –Zn(II complexes systems inhibited cell apoptosis via downregulating the nuclear factor κB (NF-κB pathway and upregulating Bcl-2/Bax pathway. In summary, the present study found that curcumin–Cu(II or –Zn(II complexes systems, especially the former, possess significant neuroprotective effects, which indicates the potential advantage of curcumin as a promising agent against AD and deserves further study.

  3. Neuroprotective Effects and Mechanisms of Curcumin-Cu(II) and -Zn(II) Complexes Systems and Their Pharmacological Implications.

    Science.gov (United States)

    Yan, Fa-Shun; Sun, Jian-Long; Xie, Wen-Hai; Shen, Liang; Ji, Hong-Fang

    2017-12-28

    Alzheimer's disease (AD) is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa , is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated. Therefore, the present study was designed to investigate the protective effects of the complexes of curcumin with Cu(II) or Zn(II) on hydrogen peroxide (H₂O₂)-induced injury and the underlying molecular mechanisms. The use of rat pheochromocytoma (PC12) cells, a widely used neuronal cell model system, was adopted. It was revealed that curcumin-Cu(II) complexes systems possessed enhanced O₂ ·- -scavenging activities compared to unchelated curcumin. In comparison with unchelated curcumin, the protective effects of curcumin-Cu(II) complexes systems were stronger than curcumin-Zn(II) system. Curcumin-Cu(II) or -Zn(II) complexes systems significantly enhanced the superoxide dismutase, catalase, and glutathione peroxidase activities and attenuated the increase of malondialdehyde levels and caspase-3 and caspase-9 activities, in a dose-dependent manner. The curcumin-Cu(II) complex system with a 2:1 ratio exhibited the most significant effect. Further mechanistic study demonstrated that curcumin-Cu(II) or -Zn(II) complexes systems inhibited cell apoptosis via downregulating the nuclear factor κB (NF-κB) pathway and upregulating Bcl-2/Bax pathway. In summary, the present study found that curcumin-Cu(II) or -Zn(II) complexes systems, especially the former, possess significant neuroprotective effects, which indicates the potential advantage of curcumin as a promising agent against AD and deserves further study.

  4. Syntheses, structures, and properties of imidazolate-bridged Cu(II)-Cu(II) and Cu(II)-Zn(II) dinuclear complexes of a single macrocyclic ligand with two hydroxyethyl pendants.

    Science.gov (United States)

    Li, Dongfeng; Li, Shuan; Yang, Dexi; Yu, Jiuhong; Huang, Jin; Li, Yizhi; Tang, Wenxia

    2003-09-22

    The imidazolate-bridged homodinuclear Cu(II)-Cu(II) complex, [(CuimCu)L]ClO(4).0.5H(2)O (1), and heterodinuclear Cu(II)-Zn(II) complex, [(CuimZnL(-)(2H))(CuimZnL(-)(H))](ClO(4))(3) (2), of a single macrocyclic ligand with two hydroxyethyl pendants, L (L = 3,6,9,16,19,22-hexaaza-6,19-bis(2-hydroxyethyl)tricyclo[22,2,2,2(11,14)]triaconta-1,11,13,24,27,29-hexaene), have been synthesized as possible models for copper-zinc superoxide dismutase (Cu(2),Zn(2)-SOD). Their crystal structures analyzed by X-ray diffraction methods have shown that the structures of the two complexes are markedly different. Complex 1 crystallizes in the orthorhombic system, containing an imidazolate-bridged dicopper(II) [Cu-im-Cu](3+) core, in which the two copper(II) ions are pentacoordinated by virtue of an N4O environment with a Cu.Cu distance of 5.999(2) A, adopting the geometry of distorted trigonal bipyramid and tetragonal pyramid, respectively. Complex 2 crystallizes in the triclinic system, containing two similar Cu-im-Zn cores in the asymmetric unit, in which both the Cu(II) and Zn(II) ions are pentacoordinated in a distorted trigonal bipyramid geometry, with the Cu.Zn distance of 5.950(1)/5.939(1) A, respectively. Interestingly, the macrocyclic ligand with two arms possesses a chairlike (anti) conformation in complex 1, but a boatlike (syn) conformation in complex 2. Magnetic measurements and ESR spectroscopy of complex 1 have revealed the presence of an antiferromagnetic exchange interaction between the two Cu(II) ions. The ESR spectrum of the Cu(II)-Zn(II) heterodinuclear complex 2 displayed a typical signal for mononuclear trigonal bipyramidal Cu(II) complexes. From pH-dependent ESR and electronic spectroscopic studies, the imidazolate bridges in the two complexes have been found to be stable over broad pH ranges. The cyclic voltammograms of the two complexes have been investigated. Both of the two complexes can catalyze the dismutation of superoxide and show rather high activity.

  5. Cu(II AND Zn(II COMPLEX COMPOUNDS WITH BIGUANIDES AROMATIC DERIVATIVES. SYNTHESIS, CHARACTERIZATION, BIOLOGICAL ACTIVITY

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    Ticuţa Negreanu-Pîrjol

    2011-05-01

    Full Text Available In this paper we report the synthesis, physical-chemical characterization and antimicrobial activity of some new complex compounds of hetero-aromatic biguanides ligands, chlorhexidine base (CHX and chlorhexidine diacetate (CHXac2 with metallic ions Cu(II and Zn(II, in different molar ratio. The synthesized complexes were characterized by elemental chemical analysis and differential thermal analysis. The stereochemistry of the metallic ions was determined by infrared spectra, UV-Vis, EPR spectroscopy and magnetic susceptibility in the aim to establish the complexes structures. The biological activity of the new complex compounds was identified in solid technique by measuring minimum inhibition diameter of bacterial and fungal culture, against three standard pathogen strains, Escherichia coli ATCC 25922, Staphilococcus aureus ATCC 25923 and Candida albicans ATCC 10231. The results show an increased specific antimicrobial activity for the complexes chlorhexidine:Cu(II 1:1 and 1:2 compared with the one of the Zn(II complexes.

  6. Coordination Behavior of Ni2+, Cu2+, and Zn2+ in Tetrahedral 1-Methylimidazole Complexes: A DFT/CSD Study

    OpenAIRE

    Tetteh, Samuel

    2018-01-01

    The interaction between nickel (Ni2+), copper (Cu2+), and zinc (Zn2+) ions and 1-methylimidazole has been studied by exploring the geometries of eleven crystal structures in the Cambridge Structural Database (CSD). The coordination behavior of the respective ions was further investigated by means of density functional theory (DFT) methods. The gas-phase complexes were fully optimized using B3LYP/GENECP functionals with 6-31G∗ and LANL2DZ basis sets. The Ni2+ and Cu2+ complexes show distorted ...

  7. Electrochemical and theoretical complexation studies for Zn and Cu with individual polyphenols

    International Nuclear Information System (INIS)

    Esparza, I.; Salinas, I.; Santamaria, C.; Garcia-Mina, J.M.; Fernandez, J.M.

    2005-01-01

    Zn and Cu interactions with three selected flavonoids (catechin, quercetin and rutin) have been electrochemically monitored. It has been shown that catechin takes one atom of metal per molecule; quercetin takes two atoms, and rutin is able to take up to three atoms. Not all ligands bind metals equally strong, and weakly bonded metals can be distinguished. Zn shows a sluggish kinetics and, at the same time, the highest conditional formation constants. The method could be applied to a real sample. Theoretical models are proposed for the most favourable compounds

  8. Influence of mechanical activation on the leaching of non-ferrous metals from a CuPbZn complex concentrate

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    Godoèíková Erika

    2000-09-01

    Full Text Available The aim of study was to research the procedures of copper, lead and zinc leaching from CuPbZn complex sulphide concentrate during the intervention of mechanical activation.Mechanical activation belongs to innovative procedures, which intensifies technological processes by means of creation of new surfaces and making defective structure of solid phase. Mechanical impact on the solid phase is a suitable procedure to ensure the mobility of its structure elements and to accumulate the mechanical energy that is later used in following processes of leaching.This paper deals with the intensification of the chloride and thiourea leaching of copper, lead and zinc from a CuPbZn complex concentrate of Hodruša-Hámre (Slovak deposit by using the mechanical activation in an attritor. Ferric chloride and thiourea were used as leaching reagents. The leaching of the concentrate with ferric chloride solution afforded 23 % recovery of Cu, 99 % of Pb and 28 % of Zn. 9 % recovery of Cu, 17 % of Pb and 3 % of Zn were achieved by the leaching with thiourea. Thus results showed that the extraction of Cu, Zn and also Pb in the case of thiourea leaching was low. The use of milling in the attritor as an innovation method of pretreatment leads to the structural degradation and increasing the surface area of the investigated concentrate from the original value of 0.18 m2g-1 to the maximum value of 4.67 m2g-1. This fact manifested itself in the subsequent process of extraction of Cu, Pb and Zn into the chloride and thiourea solutions. Our results indicate more effective leaching of pretreated concentrate in the chloride medium with recoveries of 84 % Zn and 100 % Pb. In thiourea, the recoveries for Zn and Pb were low, however 99 % Cu can be recovered. In regard to the economy, the extraction of Cu, Pb and Zn was studied in this work with the aspect of minimal energy consumption during milling. The maximum recoveries of non-ferrous metals in the solutions of ferric chloride

  9. The synthesis of N–Zn, N–Cu complexes involving 2-amino pyridine ...

    Indian Academy of Sciences (India)

    Administrator

    alcohol, and the reaction mixture was refluxed for. 14 h. The mixture was filtered to furnish white cry- .... benzaldehyde to 2-nitro-1-phenylethanol was esta- blished according to the content ratio of the remin- ... Zn(OAc)2 ·2 H2O in ethanol, THF or acetonitrile, the corresponding complexes were obtained after reflux- ing for 14 ...

  10. Unsaturated b-ketoesters and their Ni(II, Cu(II and Zn(II complexes

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    MUHAMMED BASHEER UMMATHUR

    2009-03-01

    Full Text Available A new series of b-ketoesters in which the keto group is attached to the olefinic linkage were synthesized by the reaction of methyl acetoacetate and aromatic aldehydes under specified conditions. The existence of these compounds predominantly in the intramolecularly hydrogen bonded enol form was well demonstrated from their IR, 1H-NMR and mass spectral data. Details on the formation of their [ML2] complexes with Ni(II, Cu(II and Zn(II and the nature of the bonding are discussed on the basis of analytical and spectral data.

  11. Nonempirical investigations of the structure and stability of complex boro- and alumohydrides of K, Ca, Cu and Zn

    International Nuclear Information System (INIS)

    Musaev, D.G.; Charkin, O.P.

    1991-01-01

    Using nonempirical MO LCAO SCF method the structural and relative energy characteristics of boro- and alumohydrides of alternative configurations, CuAlH 4 , ZnBH 4 + , ZnAlH 4 + and HZnAlH 4 , were calculated. Differences and similarities in the properties of identical boro- and alumohydrides, as well as L 1 MH 4 , HL 2 MH 4 and L 2 MH 4 + molecules with the change of cation in the series K + -HCa + -Ca 2+ and Cu + -HZn + -Zn 2+ on the one hand, and with Cu and Zn substitution for K and Ca on the other hand, were considered. It was shown that alumohydrides of electropositive alkali and alkaline-earth cations K and Ca are less, and those of transition metals Cu and Zn are more hard to cation migration around AlH 4 - and BH 4 - anions than borohydrides

  12. Soil solution dynamics of Cu and Zn in a Cu- and Zn-polluted soil as influenced by gamma-irradiation and Cu-Zn interaction.

    Science.gov (United States)

    Luo, Y M; Yan, W D; Christie, P

    2001-01-01

    A pot experiment was conducted to study soil solution dynamics of Cu and Zn in a Cu/Zn-polluted soil as influenced by gamma-irradiation and Cu-Zn interaction. A slightly acid sandy loam was amended with Cu and Zn (as nitrates) either singly or in combination (100 mg Cu and 150 mg Zn kg(-1) soil) and was then gamma-irradiated (10 kGy). Unamended and unirradiated controls were included, and spring barley (Hordeum vulgare L. cv. Forrester) was grown for 50 days. Soil solution samples obtained using soil moisture samplers immediately before transplantation and every ten days thereafter were used directly for determination of Cu, Zn, pH and absorbance at 360 nm (A360). Cu and Zn concentrations in the solution of metal-polluted soil changed with time and were affected by gamma-irradiation and metal interaction. gamma-Irradiation raised soil solution Cu substantially but generally decreased soil solution Zn. These trends were consistent with increased dissolved organic matter (A360) and solution pH after gamma-irradiation. Combined addition of Cu and Zn usually gave higher soil solution concentrations of Cu or Zn compared with single addition of Cu or Zn in gamma-irradiated and non-irradiated soils, indicating an interaction between Cu and Zn. Cu would have been organically complexed and consequently maintained a relatively high concentration in the soil solution under higher pH conditions. Zn tends to occur mainly as free ion forms in the soil solution and is therefore sensitive to changes in pH. The extent to which gamma-irradiation and metal interaction affected solubility and bioavailability of Cu and Zn was a function of time during plant growth. Studies on soil solution metal dynamics provide very useful information for understanding metal mobility and bioavailability.

  13. Polymerization of Methyl Methacrylate Catalyzed by Co(II), Cu(II), and Zn(II) Complexes Bearing N-Methyl-N-((pyridin-2-yl)methyl) cyclohexanamine

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Seoung Hyun; Lee, Hyosun [Kyungpook National University, Daegu (Korea, Republic of); Shin, Jongwon [POSTECH, Pohang (Korea, Republic of); Nayab, Saira [Shaheed Benazir Bhutto University, Sheringal (Pakistan)

    2016-05-15

    We demonstrated the synthesis and characterization of Co(II), Cu(II), and Zn(II) complexes ligated to N-methyl-N-((pyridin-2-yl)methyl)cyclohexanamine. The complex [Co(nmpc)Cl{sub 2}] in the presence of MMAO showed the highest catalytic activity for MMA polymerization at 60 °C compared with its Zn(II) and Cu(II) analogs. The metal center showed an obvious influence on the catalytic activity, although this appeared to have no effect on the stereo-regularity of the resultant PMMA. X-ray diffraction analysis revealed that [Co(nmpc)Cl{sub 2}] and [Zn(nmpc)Cl{sub 2}] crystallized in the monoclinic system with space group P2{sub 1}/c and existed as monomeric and solvent-free complexes.

  14. Cu(II) AND Zn(II)

    African Journals Online (AJOL)

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    SYNTHESIS OF 2,2-DIMETHYL-4-PHENYL-[1,3]-DIOXOLANE USING ZEOLITE. ENCAPSULATED Co(II), Cu(II) AND Zn(II) COMPLEXES. B.P. Nethravathi1, K. Rama Krishna Reddy2 and K.N. Mahendra1*. 1Department of Chemistry, Bangalore University, Bangalore-560001, India. 2Department of Chemistry, Government ...

  15. Equilibrium and NMR studies on GdIII, YIII, CuII and ZnII complexes of various DTPA-N,N''-bis(amide) ligands. Kinetic stabilities of the gadolinium(III) complexes.

    Science.gov (United States)

    Jászberényi, Zoltán; Bányai, István; Brücher, Ernö; Király, Róbert; Hideg, Kálmán; Kálai, Tamás

    2006-02-28

    Three DTPA-derivative ligands, the non-substituted DTPA-bis(amide) (L(0)), the mono-substituted DTPA-bis(n-butylamide) (L(1)) and the di-substituted DTPA-bis[bis(n-butylamide)] (L(2)) were synthesized. The stability constants of their Gd3+ complexes (GdL) have been determined by pH-potentiometry with the use of EDTA or DTPA as competing ligands. The endogenous Cu2+ and Zn2+ ions form ML, MHL and M(2)L species. For the complexes CuL(0) and CuL(1) the dissociation of the amide hydrogens (CuLH(-1)) has also been detected. The stability constants of complexes formed with Gd3+, Cu2+ and Zn2+ increase with an increase in the number of butyl substituents in the order ML(0) DTPA)2-, while the complex GdL2 possesses a much higher kinetic stability.

  16. Effects of organic complexed or inorganic Co, Cu, Mn and Zn supplementation during a 45-day preconditioning period on productive and health responses of feeder cattle.

    Science.gov (United States)

    Lippolis, K D; Cooke, R F; Silva, L G T; Schubach, K M; Brandao, A P; Marques, R S; Larson, C K; Russell, J R; Arispe, S A; DelCurto, T; Bohnert, D W

    2017-11-01

    This experiment evaluated production and health parameters among cattle offered concentrates containing inorganic or organic complexed sources of supplemental Cu, Co, Mn and Zn during a 45-day preconditioning period. In total, 90 Angus×Hereford calves were weaned at 7 months (day -1), sorted by sex, weaning BW and age (261±2 kg; 224±2 days), and allocated to 18 drylot pens (one heifer and four steers per pen) on day 0; thus, all pens had equivalent initial BW and age. Pens were randomly assigned to receive a corn-based preconditioning concentrate containing: (1) Cu, Co, Mn and Zn sulfate sources (INR), (2) Cu, Mn, Co and Zn complexed organic source (AAC) or (3) no Cu, Co, Mn and Zn supplementation (CON). From day 0 to 45, cattle received concentrate treatments (2.7 kg/animal daily, as-fed basis) and had free-choice access to orchardgrass (Dactylis glomerata L.), long-stem hay and water. The INR and AAC treatments were formulated to provide the same daily amount of Co, Cu, Mn and Zn at a 50-, 16-, 8- and ninefold increase, respectively, compared with the CON treatment. On day 46, cattle were transported to a commercial feedlot, maintained as a single pen, and offered a free-choice receiving diet until day 103. Calf full BW was recorded on days -1 and 0, 45 and 46, and 102 and 103 for average daily gain (ADG) calculation. Liver biopsy was performed on days 0 (used as covariate), 22 and 45. Cattle were vaccinated against respiratory pathogens on days 15, 29 and 46. Blood samples were collected on days 15, 29, 45, 47, 49, 53 and 60. During preconditioning, mean liver concentrations of Co, Zn and Cu were greater (P⩽0.03) in AAC and INR compared with CON. No treatment effects were detected (P⩾0.17) for preconditioning feed intake, ADG or feed efficiency. No treatment effects were detected (P⩾0.48) for plasma concentrations of antibodies against Mannheimia haemolytica, bovine viral diarrhea types 1 and 2 viruses. Plasma haptoglobin concentrations were similar

  17. trans-Methylpyridine cyclen versus cross-bridged trans-methylpyridine cyclen. Synthesis, acid-base and metal complexation studies (metal = Co2+, Cu2+, and Zn2+).

    Science.gov (United States)

    Bernier, Nicolas; Costa, Judite; Delgado, Rita; Félix, Vítor; Royal, Guy; Tripier, Raphaël

    2011-05-07

    The synthesis of the cross-bridged cyclen CRpy(2) {4,10-bis((pyridin-2-yl)methyl)-1,4,7,10-tetraazabicyclo[5.5.2]tetradecane}, a constrained analogue of the previously described trans-methylpyridine cyclen Cpy(2) is reported. The additional ethylene bridge confers to CRpy(2) proton-sponge type behaviour which was explored by NMR and potentiometric studies. Transition metal complexes have been synthesized (by complexation of both ligands with Co(2+), Cu(2+) and Zn(2+)) and characterized in solution and in the solid state. The single crystal X-ray structures of [CoCpy(2)](2+), [CuCpy(2)](2+) and [ZnCpy(2)](2+) complexes were determined. Stability constants of the complexes, including those of the cross-bridged derivative, were determined using potentiometric titration data and the kinetic inertness of the [CuCRpy(2)](2+) complex in an acidic medium (half-life values) was evaluated by spectrophotometry. The pre-organized structure of the cross-bridged ligand imposes an additional strain for the complexation leading to complexes with smaller thermodynamic stability in comparison with the related non-bridged ligand. The electrochemical study involving cyclic voltammetry underlines the importance of the ethylene cross-bridge on the redox properties of the transition metal complexes.

  18. The synthesis of N-Zn, N-Cu complexes involving 2-amino pyridine ...

    Indian Academy of Sciences (India)

    amino pyridine and ethylenediamine ligands (1a-b and 2a-b) have been described. They were synthesized with a simple, one-pot method, and the crystal structures of 1a, 1b, 2a and 2b were determined by X-ray crystallography. The complexes ...

  19. The complexity of non-Schmid behavior in the CuZnAl shape memory alloy

    Science.gov (United States)

    Alkan, S.; Ojha, A.; Sehitoglu, H.

    2018-05-01

    The paper addresses one of the most important yet overlooked phenomenon in shape memory research- the plastic slip response. We show that the slip response is highly crystal orientation dependent and we demonstrate the precise reasons behind such complex response. The fractional dislocations on {112} or {011} systems can be activated depending on the sample orientation and solutions are derived for the variations in disregistries and dislocation core spreadings. This leads to the calculation of critical resolved shear stress in close agreement with experimental trends. The results show considerable dependence of the flow behavior on the non-Schmid stress components and the proposed yield criterion captures the role of stress tensor components.

  20. Synthesis, structures, nuclease activity, cytotoxicity, DFT and molecular docking studies of two nitrato bridged homodinuclear (Cu-Cu, Zn-Zn) complexes containing 2,2'-bipyridine and a chalcone derivative.

    Science.gov (United States)

    Gaur, Ruchi; Choubey, Diksha Kumari; Usman, Mohammad; Ward, Benzamin D; Roy, Jagat Kumar; Mishra, Lallan

    2017-08-01

    Nitrato briged dinuclear complexes of type [Cu 2 (L) 2 (bpy) 2 (NO 3 )](NO 3 )·4H 2 O, 1 and [Zn 2 (L) 2 (bpy) 2 (NO 3 )](NO 3 )·4H 2 O, 2 (L=deprotonated form of free ligand LH, [1-(2-hydroxyphenyl)-3-(9-anthracenyl) propenone; bpy=2,2'bipyridine] are synthesized and characterized using a battery of physicochemical techniques and X-ray crystallography. A distorted square pyramidal geometry is assigned to them with N 2 O 3 coordination core around the metal ion. The co-ligand L binds the metal ions through its O,O' atoms in anti-syn mode. The metal centers in complexes 1 and 2 are separated via bridging nitrato group at a distance of 6.073Å and 5.635Å respectively. Their structures and absorption spectra are supported by the computational studies using density functional theory (DFT) and TD-DFT. Both complexes exhibit nuclease activity and cleave supercoiled (form I) DNA. The complex 1 preferentially binds major groove of DNA and follows an oxidative pathway whereas complex 2 binds with minor groove of DNA via hydrolytic pathway. Both complexes inhibit topoisomerase I relaxation activity with IC 50 values of 7 and 35μM. Molecular docking studies support the groove binding and topoisomerase I binding of the complexes. The complex 1 showed a significant cytotoxicity against HeLa cell lines (a cervical cancer cell lines) in vitro with IC 50 value calculated as 2.9±0.021μM as compared to 28.2±0. 044μΜ for complex 2. Complex 2 induces the cell apoptosis at a later-stage as compared to complex 1. The cell apoptosis and topoisomerase inhibition by complexes enable them to be potential candidates as future anticancer drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Model studies of the Cu(B) site of cytochrome c oxidase utilizing a Zn(II) complex containing an imidazole-phenol cross-linked ligand.

    Science.gov (United States)

    Pesavento, Russell P; Pratt, Derek A; Jeffers, Jerry; van der Donk, Wilfred A

    2006-07-21

    Cytochrome c oxidase, the enzyme complex responsible for the four-electron reduction of O2 to H2O, contains an unusual histidine-tyrosine cross-link in its bimetallic heme a3-CuB active site. We have synthesised an unhindered, tripodal chelating ligand, BPAIP, containing the unusual ortho-imidazole-phenol linkage, which mimics the coordination environment of the CuB center. The ligand was used to investigate the physicochemical (pKa, oxidation potential) and coordination properties of the imidazole-phenol linkage when bound to a dication. Zn(II) coordination lowers the pKa of the phenol by 0.6 log units, and increases the potential of the phenolate/phenoxyl radical couple by approximately 50 mV. These results are consistent with inductive withdrawal of electron density from the phenolic ring. Spectroscopic data and theoretical calculations (DFT) were used to establish that the cationic complex [Zn(BPAIP)Br]+ has an axially distorted trigonal bipyramidal structure, with three coordinating nitrogen ligands (two pyridine and one imidazole) occupying the equatorial plane and the bromide and the tertiary amine nitrogen of the tripod in the axial positions. Interestingly, the Zn-Namine bonding interaction is weak or absent in [Zn(BPAIP)Br]+ and the complex gains stability in basic solutions, as indicated by 1H NMR spectroscopy. These observations are supported by theoretical calculations (DFT), which suggest that the electron-donating capacity of the equatorial imidazole ligand can be varied by modulation of the protonation and/or redox state of the cross-linked phenol. Deprotonation of the phenol makes the equatorial imidazole a stronger sigma-donor, resulting in an increased Zn-Nimd interaction and thereby leading to distortion of the axial ligand axis toward a more tetrahedral geometry.

  2. Biologically active new Fe(II, Co(II, Ni(II, Cu(II, Zn(II and Cd(II complexes of N-(2-thienylmethylenemethanamine

    Directory of Open Access Journals (Sweden)

    C. SPÎNU

    2008-04-01

    Full Text Available Iron(II, cobalt(II, nickel (II, copper (II, zinc(II and cadmium(II complexes of the type ML2Cl2, where M is a metal and L is the Schiff base N-(2-thienylmethylenemethanamine (TNAM formed by the condensation of 2-thiophenecarboxaldehyde and methylamine, were prepared and characterized by elemental analysis as well as magnetic and spectroscopic measurements. The elemental analyses suggest the stoichiometry to be 1:2 (metal:ligand. Magnetic susceptibility data coupled with electronic, ESR and Mössbauer spectra suggest a distorted octahedral structure for the Fe(II, Co(II and Ni(II complexes, a square-planar geometry for the Cu(II compound and a tetrahedral geometry for the Zn(II and Cd(II complexes. The infrared and NMR spectra of the complexes agree with co-ordination to the central metal atom through nitrogen and sulphur atoms. Conductance measurements suggest the non-electrolytic nature of the complexes, except for the Cu(II, Zn(II and Cd(II complexes, which are 1:2 electrolytes. The Schiff base and its metal chelates were screened for their biological activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and the metal chelates were found to possess better antibacterial activity than that of the uncomplexed Schiff base.

  3. Synthesis, characterization, DNA interaction and antimicrobial screening of isatin-based polypyridyl mixed-ligand Cu(II and Zn(II complexes

    Directory of Open Access Journals (Sweden)

    NATARAJAN RAMAN

    2010-06-01

    Full Text Available Several mixed ligand Cu(II/Zn(II complexes using 3-(phenyl-imino-1,3-dihydro-2H-indol-2-one (obtained by the condensation of isatin and aniline as the primary ligand and 1,10-phenanthroline (phen/2,2’-bipyridine (bpy as an additional ligand were synthesized and characterized analytically and spectroscopically by elemental analyses, magnetic susceptibility and molar conductance measurements, as well as by UV–Vis, IR, NMR and FAB mass spectroscopy. The interaction of the complexes with calf thymus (CT DNA was studied using absorption spectra, cyclic voltammetric and viscosity measurements. They exhibit absorption hypochromicity, and the specific viscosity increased during the binding of the complexes to calf thymus DNA. The shifts in the oxidation–reduction potential and changes in peak current on addition of DNA were shown by CV measurements. The Cu(II/Zn(II complexes were found to promote cleavage of pUC19 DNA from the supercoiled form I to the open circular form II and linear form III. The complexes show enhanced antifungal and antibacterial activities compared with the free ligand.

  4. First-principles study of defect formation in a photovoltaic semiconductor Cu2ZnGeSe4

    Science.gov (United States)

    Nishihara, Hironori; Maeda, Tsuyoshi; Wada, Takahiro

    2018-02-01

    The formation energies of neutral Cu, Zn, Ge, and Se vacancies in kesterite-type Cu2ZnGeSe4 were evaluated by first-principles pseudopotential calculations using plane-wave basis functions. The calculations were performed at typical points in Cu-(Zn1/2Ge1/2)-Se and Cu3Se2-ZnSe-GeSe2 pseudoternary phase diagrams for Cu2ZnGeSe4. The results were compared with those for Cu2ZnSnSe4, Cu2ZnGeS4, and Cu2ZnSnS4 calculated using the same version of the CASTEP program code. The results indicate that Cu vacancies are easily formed in Cu2ZnGeSe4 under the Cu-poor condition as in the above compounds and CuInSe2, suggesting that Cu2ZnGeSe4 is also a preferable p-type absorber material for thin-film solar cells. The formation energies of possible antisite defects, such as CuZn and CuGe, and of possible complex defects, such as CuZn+ZnCu, were also calculated and compared within the above materials. The antisite defect of CuZn, which has the smallest formation energy within the possible defects, is concluded to be the most hardly formed in Cu2ZnGeSe4 among the compounds.

  5. Electrospray ionization mass spectrometric investigations of the complexation behavior of macrocyclic thiacrown ethers with bivalent transitional metals (Cu, Co, Ni and Zn).

    Science.gov (United States)

    Tsybizova, Alexandra; Tarábek, Ján; Buchta, Michal; Holý, Petr; Schröder, Detlef

    2012-10-15

    Heavy metals are both a problem for the environment and an important resource for industry. Their selective extraction by means of organic ligands therefore is an attractive topic. The coordination of three thiacrown ethers to late 3d-metal ions was investigated by a combination of electrospray ionization mass spectrometry (ESI-MS) and electron paramagnetic resonance (EPR). The mass spectrometric experiments were carried out in an ion trap mass spectrometer with an ESI source. Absolute binding constants were estimated by comparison with data for 18-crown-6/Na(+). EPR spectroscopy was used as a complementary method for investigating the Cu(I) /Cu(II) redox couple. The study found that thiacrown ethers preferentially bind traces of copper even at an excess of other metal ions (Co(II), Ni(II), and Zn(II)). The absolute association constants of the Cu(I) complexes were about 10(8) M(-1), and about two orders of magnitude lower for the other 3d-metal cations. The EPR spectra demonstrated that the reduction from Cu(II) to Cu(I) upon formation of the [(thiacrown)Cu](+) species takes place in solution. ESI-MS demonstrated that the three thiacrown ligands examined had high binding constants as well as good selectivities for copper(I) at low concentrations, and in the presence of other metal ions. By a combination of ESI-MS and EPR spectrometry it was shown that the reduction from Cu(II) to Cu(I) occurred in solution. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Effect on the Inhibitory Activity of Potential Microbes on the Complexation of Methyl Anthranilate Derived Hydrazide with Cu, Ni and Zn (II) Metal Ions

    International Nuclear Information System (INIS)

    Ikram, M.; Rehman, S.; Khan, K.

    2013-01-01

    The hydrazide ligand 2-amino-(N-aminobezoyl)benzohydrazide (ABH) have been synthesized and characterized by 1H-NMR, 13C-NMR, ES+-MS, elemental analyses and infrared studies. The ligand was complexed with Ni(II), Cu(II) and Zn(II) metal ions and were characterized by analytical and spectroscopic methods including elemental analyses, ES+-MS, conductance, infrared, UV-Visible and magnetic susceptibilities studies. Infrared spectra show that the ligand form complexes through -NH2 and carbonyl moieties, the elemental studies suggested the M(ABH)X2 composition of the coordination compounds. The synthesized complexes were studied for their biological activities against gram negative bacteria including Escherichia coli, Salmonella typhi, Enterobacter aerogenes, Proteus vulgaris, Pseudomonas aeruginosa, Gram positive bacterial strains like Staphylococcus aureus and fungus like Candida albican. These activities show that the metal complexes are more active to the tested microbes as compared to neat ligand. (author)

  7. Synthesis and characterization of heterobimetallic complexes of the type [Cu(pn2][MCl4] where M = Co(II, Ni(II, Cu(II, Zn(II, Cd(II, and Hg(II

    Directory of Open Access Journals (Sweden)

    Seema Yadav

    2016-11-01

    Full Text Available A series of new bimetallic transition metal complexes of the type [Cu(pn2] [MCl4] have been synthesized (where M = Co(II, Ni(II, Cu(II, Zn(II, Cd(II and Hg(II, pn = 1,3-diaminopropane and characterized by elemental analysis, molar conductance, TGA, IR and electronic spectra. All the compounds are 1:1 electrolyte in DMF. The Cu(II ion is square-planar while metal ions in the anionic moiety acquire their usual tetrahedral arrangement. On the basis of these studies it is concluded that anionic moiety is electrically stabilized by its cationic counterpart.

  8. Synthesis and Characterization of Some New Cu(II, Ni(II and Zn(II Complexes with Salicylidene Thiosemicarbazones: Antibacterial, Antifungal and in Vitro Antileukemia Activity

    Directory of Open Access Journals (Sweden)

    Tudor Rosu

    2013-07-01

    Full Text Available Thirty two new Cu(II, Ni(II and Zn(II complexes (1–32 with salicylidene thiosemicarbazones (H2L1–H2L10 were synthesized. Salicylidene thiosemicarbazones, of general formula (XN-NH-C(S-NH(Y, were prepared through the condensation reaction of 2-hydroxybenzaldehyde and its derivatives (X with thiosemicarbazide or 4-phenylthiosemicarbazide (Y = H, C6H5. The characterization of the new formed compounds was done by 1H-NMR, 13C-NMR, IR spectroscopy, elemental analysis, magnetochemical, thermoanalytical and molar conductance measurements. In addition, the structure of the complex 5 has been determined by X-ray diffraction method. All ligands and metal complexes were tested as inhibitors of human leukemia (HL-60 cells growth and antibacterial and antifungal activities.

  9. Usage of a statistical method of designing factorial experiments in the mechanical activation of a complex CuPbZn sulphide concentrate

    Directory of Open Access Journals (Sweden)

    BalហPeter

    2003-09-01

    Full Text Available Mechanical activation belongs to innovative procedures which intensify technological processes by creating new surfaces and making a defective structure of solid phase. Mechanical impact on the solid phase is a suitable procedure to ensure the mobility of its structure elements and to accumulate the mechanical energy that is later used in the processes of leaching.The aim of this study was to realize the mechanical activation of a complex CuPbZn sulphide concentrate (Slovak deposit in an attritor by using of statistical methods for the design of factorial experiments and to determine the conditions for preparing the optimum mechanically activated sample of studied concentrate.The following parameters of the attritor were studied as variables:the weight of sample/steel balls (degree of mill filling, the number of revolutions of the milling shaft and the time of mechanical activation. Interpretation of the chosen variables inducing the mechanical activation of the complex CuPbZn concentrate was also carried out by using statistical methods of factorial design experiments. The presented linear model (23 factorial experiment does not support directly the optimum search, therefore this model was extended to the nonlinear model by the utilization of second order ortogonal polynom. This nonlinear model does not describe adequately the process of new surface formation by the mechanical activation of the studied concentrate. It would be necessary to extend the presented nonlinear model to the nonlinear model of the third order or choose another model. In regard to the economy with the aspect of minimal energy input consumption, the sample with the value of 524 kWht-1 and with the maximum value of specific surface area 8.59 m2g-1 (as a response of the factorial experiment was chosen as the optimum mechanically activated sample of the studied concentrate. The optimum mechanically activated sample of the complex CuPbZn sulphide concentrate was prepared

  10. Synthesis, characterization and biological studies of metal complexes of Co (II), Ni (II), Cu (II), Zn (II) with sulphadimidine-benzylidene

    International Nuclear Information System (INIS)

    Tahira, F.; Imran, M.; Iqbal, J.

    2009-01-01

    Some novel complexes of Co (II), Ni (II), Cu (II), and Zn (II) have been synthesized with a Schiff base ligand derived from sulphadimidine and benzaldehyde. The structural features of the complexes have been determined by elemental analysis, magnetic susceptibility, conductance measurement, UV/ Vis. and infrared spectroscopy. IR studies revealed that the Schiff base ligand Sulphadimidine-benzylidene has monoanionic bidendate nature and coordinate with metal ions through nitrogen atom of azomethine (>C = N) and deprotonated -NH group. All the complexes were assigned octahedral geometry on the basis of magnetic moment and electronic spectroscopic data. Low value of conductance supports their non-electrolytic nature. The ligand, as well as its complexes were checked for their in vitro antimicrobial activities against two gram positive bacterial strains, Bacillus subtillus. Staphylococcus aureus and one gram negative Salmonella typhae and five fungal strains, Nigrospora oryzae, Curvularia lunata, Drechslera rostrata, Aspergillus niger and Candida olbicans by disc diffusion method and agar plate technique, respectively. Both the antibacterial and antitungal activities of the synthesized metal complexes were found to be more as compared to parent drug and uncomplexed ligand. All the complexes contain coordinated water, which is lost at 141-160 degree C. (author)

  11. Thermodynamics and kinetics insight into reaction mechanism of Cu{sub 2}ZnSnSe{sub 4} nanoink based on binary metal-amine complexes in polyetheramine-synthesized process

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chi-Jie [Institute of Microelectronics and Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Shei, Shih-Chang, E-mail: scshei@mail.nutn.edu.tw [Department of Electrical Engineering, National University of Tainan, 700, Taiwan, ROC (China); Chang, Shoou-Jinn [Institute of Microelectronics and Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China)

    2016-08-15

    This paper reports on the reaction mechanism of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) nanoink via a solvent-thermal reflux method using copper (Cu), zinc (Zn), tin (Sn), and selenium (Se) powders as precursors and polyetheramine as a reaction solvent. The formation of CZTSe nanoparticles in polyetheramine began with the formation of binary phase CuSe and CuSe{sub 2} due to the strong catalysis provided by polyetheramine. Finally, ternary crystals of Cu{sub 2}SnSe{sub 3} transformed into well-dispersed nanocrystals of Cu{sub 2}ZnSnSe{sub 4}. The size of the crystals was shown to decrease with reaction time due to the emulsification effect of the polyetheramine epoxy group. The PH value-reaction time curves for single Cu, Zn elements and CZTSe from all participants elements reacted together have a relationship just reversed each other and both multistage feature were observed, which indicates that the CZTSe reaction was dominated by copper and zinc elements. The PH-temperature mechanism demonstrates that the reaction was controlled by the formation of metal-amine complexes, especially, after heating the PH-time variation manner is the same for pure element and all four elements reacted together. To the best of our knowledge, this is the first study on the mechanism underlying CZTSe formation based on the reactivity and stability of reaction species. - Highlights: • Reaction mechanism of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) nanoink via a solvent-thermal reflux method using polyetheramine was developed. • PH effect on thermal dynamics and characteristics of reagents and solvents in the CZTSe nanoink has been realized. • PH-temperature mechanism demonstrates that the reaction controlled by the formation of metal-amine complexes.

  12. Studying Selective Transparency in ZnS/ Cu/ ZnS Thin Films

    International Nuclear Information System (INIS)

    Ksibe, A.; Howari, H.; Diab, M.

    2009-01-01

    Dielectric/ Metal/ Dielectric (DMD) thin films deposited on glass offer of significant energy saving in buildings and can find other applications of advanced materials design. In an effort to reduce the complexity and cost production of DMD films, physical vapor deposition was used for the laboratory manufacture of ZnS/ Cu/ ZnS films on glass. ZnS was used because of its high refractive index, ease of deposition and low cost; Cu was used because of its low absorption in the visible spectrum and its thermal stability. The films produced were of good quality, with transmittance as high as 85%. The ZnS layers were found not only to antireflect the Ag layer, but also to stabilize the ZnS/ Cu/ ZnS films, improve its adherence on glass and increase the film thermal resistance up to 240 C. The influence of annealing on the optical properties was investigated. The experimental results show that the properties of the multilayers are improved with annealing in air. the change of maximum transmission indicates that, with the increase of annealing temperature, maximum transmittance was change. Multilayer films annealed at after 200 C, show a decrease in the maximum transmittance witch might be due to the diffused Cu atoms onto ZnS layer. (author)

  13. Antibacterial Co(II, Ni(II, Cu(II and Zn(II complexes with biacetyl-derived Schiff bases

    Directory of Open Access Journals (Sweden)

    MUHAMMAD IMRAN

    2010-08-01

    Full Text Available The condensation reactions of biacetyl with ortho-hydroxyaniline and 2-aminobenzoic acid to form bidendate NO donor Schiff bases were studied. The prepared Schiff base ligands were further utilized for the formation of metal chelates having the general formula [ML2(H2O2] where M = Co(II, Ni(II, Cu(II and Zn(II and L = HL1 and HL2. These new compounds were characterized by conductance measurements, magnetic susceptibility measurements, elemental analysis, and IR, 1H-NMR, 13C-NMR and electronic spectroscopy. Both Schiff base ligands were found to have a mono-anionic bidentate nature and octahedral geometry was assigned to all metal complexes. All the complexes contained coordinated water which was lost at 141–160 °C. These compounds were also screened for their in vitro antibacterial activity against four bacterial species, namely: Escherichia coli, Staphylococcus aureus, Salmonella typhi and Bacillus subtilis. The metal complexes were found to have greater antibacterial activity than the uncomplexed Schiff base ligands.

  14. Solar photocatalytic removal of Cu(II), Ni(II), Zn(II) and Pb(II): Speciation modeling of metal-citric acid complexes

    International Nuclear Information System (INIS)

    Kabra, Kavita; Chaudhary, Rubina; Sawhney, R.L.

    2008-01-01

    The present study is targeted on solar photocatalytic removal of metal ions from wastewater. Photoreductive deposition and dark adsorption of metal ions Cu(II), Ni(II), Pb(II) and Zn(II), using solar energy irradiated TiO 2 , has been investigated. Citric acid has been used as a hole scavenger. Modeling of metal species has been performed and speciation is used as a tool for discussing the photodeposition trends. Ninety-seven percent reductive deposition was obtained for copper. The deposition values of other metals were significantly low [nickel (36.4%), zinc (22.2%) and lead (41.4%)], indicating that the photocatalytic treatment process, using solar energy, was more suitable for wastewater containing Cu(II) ions. In absence of citric acid, the decreasing order deposition was Cu(II) > Ni(II) > Pb(II) > Zn(II), which proves the theoretical thermodynamic predictions about the metals

  15. One-Step Synthesis of Cu–ZnO@C from a 1D Complex [Cu0.02Zn0.98(C8H3NO6(C12H8N2]n for Catalytic Hydroxylation of Benzene to Phenol

    Directory of Open Access Journals (Sweden)

    Guanghui Wang

    2018-05-01

    Full Text Available A novel one-dimensional bimetallic complex [Cu0.02Zn0.98(C8H3NO6(C12H8N2]n (“Complex” has been synthesized by a hydrothermal method. A Cu–ZnO@C composite was obtained by a one-step pyrolysis of Complex. Correlated with the characterization results, it is confirmed that both metallic Cu0 and ZnO nanoparticles were highly dispersed on/in the carbon substrate. This simple one-step pyrolysis method avoids the high-temperature pretreatment under H2 commonly required for preparation of such Cu–ZnO catalysts. The Cu–ZnO@C composite was tested with respect to its catalytic activities for the hydroxylation of benzene to phenol with H2O2. The results indicate that the benzene conversion, phenol yield, and phenol selectivity reached the maximum values (55.7%, 32%, and 57.5%, respectively at Complex carbonized at 600 °C, and were higher than those of the commercial mixed sample. Compared with the other candidate catalysts, the turnover frequency (TOF of our Cu–ZnO@C catalyst (117.9 mmol mol−1 s−1 can be ranked at the top. The higher catalytic activities should be due to the highly dispersed metallic Cu0 and ZnO particles as well as their synergistic interaction.

  16. Synthesis, Characterization, and Biological Activity of Mn(II, Fe(II, Co(II, Ni(II, Cu(II, Zn(II, and Cd(II Complexes of N-Thiophenoyl-N′-Phenylthiocarbohydrazide

    Directory of Open Access Journals (Sweden)

    M. Yadav

    2013-01-01

    Full Text Available Mn(II, Fe(II, Co(II, Ni(II, Cu(II, Zn(II, and Cd(II complex of N-thiophenoyl -N′-phenylthiocarbohydrazide (H2 TPTH have been synthesized and characterized by elemental analysis, magnetic susceptibility measurements, infrared, NMR, electronic, and ESR spectral studies. The complexes were found to have compositions [Mn(H TPTH2], [Co(TPTH (H2O2], [Ni(TPTH (H2O2], [Cu(TPTH], [Zn(H TPTH], [Cd(H TPTH2], and [Fe(H TPTH2(EtOH]. The magnetic and electronic spectral studies suggest square planar geometry for [Cu(TPTH], tetrahedral geometry for [Zn(TPTH] and [Cd(H TPTH2], and octahedral geometry for rest of the complexes. The infrared spectral studies of the 1 : 1 deprotonated complexes suggest bonding through enolic oxygen, thiolato sulfur, and both the hydrazinic nitrogens. Thus, H2TPTH acts as a binegative tetradentate ligand. H2 TPTH and its metal complexes have been screened against several bacteria and fungi.

  17. Micellar effect on metal-ligand complexes of Co(II, Ni(II, Cu(II and Zn(II with citric acid

    Directory of Open Access Journals (Sweden)

    Nageswara Rao Gollapalli

    2009-12-01

    Full Text Available Chemical speciation of citric acid complexes of Co(II, Ni(II, Cu(II and Zn(II was investigated pH-metrically in 0.0-2.5% anionic, cationic and neutral micellar media. The primary alkalimetric data were pruned with SCPHD program. The existence of different binary species was established from modeling studies using the computer program MINIQUAD75. Alkalimetric titrations were carried out in different relative concentrations (M:L:X = 1:2:5, 1:3:5, 1:5:3 of metal (M to citric acid. The selection of best chemical models was based on statistical parameters and residual analysis. The species detected were MLH, ML2, ML2H and ML2H2. The trend in variation of stability constants with change in mole fraction of the medium is explained on the basis of electrostatic and non-electrostatic forces. Distributions of the species with pH at different compositions of micellar media are also presented.

  18. Electrodeposition and properties of Zn, Cu, and Cu{sub 1−x} Zn{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Özdemir, Rasim [Kilis Vocational High School, Kilis 7 Aralık University, 79000 Kilis (Turkey); Karahan, İsmail Hakkı, E-mail: ihkarahan@gmail.com [Department of Metallurgical and Materials Engineering, Faculty of Technology, Mustafa Kemal University, 31040 Hatay (Turkey)

    2014-11-01

    Highlights: • Cu, Zn and Cu–Zn deposits successfully deposited from the non-cyanide sulphate electrolyte. • The effect of alloying element was investigated on the electrical resistivity and the structure of Cu–Zn alloy. • The average crystallite size of the samples varied from 66 to 161 nm and decreased when the Zn and Cu combined in Cu–Zn. • Microstrain has been decreased with increasing crystallite size. • Electrical resistivity of alloy was obtained between the Zn and Cu films. - Abstract: The electrodeposition of Cu, Zn and Cu–Zn deposits from the non-cyanide Zn sulphate and Cu sulphate reduced by citrate at constant stirring speed has been investigated. The composition of the Cu–Zn bath was shown to influence the morphology, electrical resistivity, phase composition, and Cu and Zn content of the Cu–Zn deposits. Their structural and electrical properties have been investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDAX), cyclic voltammeter (CV) and current–voltage measurements against the temperature for electrical resistivity, respectively. XRD shows that Cu–Zn samples are polycrystalline phase. Resistivity results show that the copper film exhibits bigger residual resistivity than both the zinc and the Cu–Zn alloy. Theoretical calculations of the XRD peaks demonstrate that the average crystallite size of the Cu–Zn alloy decreased and microstrain increased when the Cu alloyed with zinc.

  19. Cu(II), Zn(II)

    African Journals Online (AJOL)

    the kinetic parameters as order of decomposition reaction, activation energy and ..... Cu as anode material, K - alpha [Å] = 1.54060 and the generator settings 30 .... Calculated quantum chemical parameters for ligand and its metal complexes.

  20. Neuroprotective Effects and Mechanisms of Curcumin–Cu(II) and –Zn(II) Complexes Systems and Their Pharmacological Implications

    OpenAIRE

    Yan, Fa-Shun; Sun, Jian-Long; Xie, Wen-Hai; Shen, Liang; Ji, Hong-Fang

    2017-01-01

    Alzheimer’s disease (AD) is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa, is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated....

  1. Aminoacid N-substituted 1,4,7-triazacyclononane and 1,4,7,10-tetraazacyclododecane Zn2+, Cd2+ and Cu2+ complexes. A preparative, potentiometric titration and NMR spectroscopic study.

    Science.gov (United States)

    Plush, Sally E; Lincoln, Stephen F; Wainwright, Kevin P

    2004-05-07

    The pK(a)s and Zn2+, Cd2+ and Cu2+ complexation constants (K) for 1,4,7-tris[(2''S)-acetamido-2''-(methyl-3''-phenylpropionate)]-1,4,7-triazacyclononane, 1, 1,4,7-tris[(2''S)-acetamido-2''-(1''-carboxy-3''-phenylpropane)]-1,4,7-triazacyclononane, H(3)2, 1,4,7-tris[(2''S)-acetamido-2''-(methyl-3''-(1H-3-indolyl)propionate)]-1,4,7-triazacyclononane, 3, and 1,4,7,10-tetrakis[(2''S)-acetamido-2''-(methyl-3''-phenylpropionate)]-1,4,7,10-tetraazacyclododecane, 4, 1,4,7,10-tetrakis[(2''S)-acetamido-2''-(1''-carboxy-3''-phenylpropane)]-1,4,7,10-tetraazacyclododecane, H(4)5, in 20 : 80 v/v water-methanol solution are reported. The pK(a)s within the potentiometric detection range for H(3)1(3+) = 8.69 and 3.59, for H(6)2(3+) = 9.06, 6.13, 4.93 and 4.52, H(3)3(3+) = 8.79 and 3.67, H(4)4(4+) = 8.50, 5.62 and 3.77 and for H(8)5(4+) = 9.89, 7.06, 5.53, 5.46, 4.44 and 4.26 where each tertiary amine nitrogen is protonated. The complexes of 1: [Zn(1)]2+(9.00), [Cd(1)]2+ (6.49), [Cd(H1)]3+ (4.54) and [Cu(1)]2+ (10.01) are characterized by the log(K/dm3 mol(-1)) values shown in parentheses. Analogous complexes are formed by 3 and 4: [Zn(3)]2+ (10.19), [Cd(3)]2+ (8.54), [Cu(3)]2+ (10.77), [Zn(4)]2+ (11.41) [Cd(4)]2+ (9.16), [Cd(H4)]3+ (6.16) and [Cu(4)]2+ (11.71). The tricarboxylic acid H(3)2 generates a greater variety of complexes as exemplified by: [Zn(2)-] (10.68) [Zn(H2)] (6.60) [Zn(H(2)2)+] (5.15), [Cd(2)](-) (4.99), [Cd(H2)] (4.64), [Cd(H2(2))]+ (3.99), [Cd(H(3)2)]2+ (3.55), [Cu(2)](-) (12.55) [Cu(H2)] (7.66), [Cu(H(2)2)]+ (5.54) and [Cu(2)2](4-) (3.23). The complexes of H(4)5 were insufficiently soluble to study in this way. The 1H and 13C NMR spectra of the ligands are consistent with formation of a predominant Zn2+ and Cd2+ Delta or Lambda diastereomer. The preparations of the new pendant arm macrocycles H(3)2, 3, 4 and H(4)5 are reported.

  2. Synthesis, spectral characterization thermal stability, antimicrobial studies and biodegradation of starch–thiourea based biodegradable polymeric ligand and its coordination complexes with [Mn(II, Co(II, Ni(II, Cu(II, and Zn(II] metals

    Directory of Open Access Journals (Sweden)

    Nahid Nishat

    2016-09-01

    Full Text Available A biodegradable polymer was synthesized by the modification reaction of polymeric starch with thiourea which is further modified by transition metals, Mn(II, Co(II, Ni(II, Cu(II and Zn(II. All the polymeric compounds were characterized by (FT-IR spectroscopy, 1H NMR spectroscopy, 13C NMR spectroscopy, UV–visible spectra, magnetic moment measurements, thermogravimetric analysis (TGA and antibacterial activities. Polymer complexes of Mn(II, Co(II and Ni(II show octahedral geometry, while polymer complexes of Cu(II and Zn(II show square planar and tetrahedral geometry, respectively. The TGA revealed that all the polymer metal complexes are more thermally stable than their parental ligand. In addition, biodegradable studies of all the polymeric compounds were also carried out through ASTM-D-5338-93 standards of biodegradable polymers by CO2 evolution method which says that coordination decreases biodegradability. The antibacterial activity was screened with the agar well diffusion method against some selected microorganisms. Among all the complexes, the antibacterial activity of the Cu(II polymer–metal complex showed the highest zone of inhibition because of its higher stability constant.

  3. Room temperature ferromagnetism in Cu doped ZnO

    Science.gov (United States)

    Ali, Nasir; Singh, Budhi; Khan, Zaheer Ahmed; Ghosh, Subhasis

    2018-05-01

    We report the room temperature ferromagnetism in 2% Cu doped ZnO films grown by RF magnetron sputtering in different argon and oxygen partial pressure. X-ray photoelectron spectroscopy was used to ascertain the oxidation states of Cu in ZnO. The presence of defects within Cu-doped ZnO films can be revealed by electron paramagnetic resonance. It has been observed that saturated magnetic moment increase as we increase the zinc vacancies during deposition.

  4. Fe (III), Co(II), Ni(II), Cu(II) and Zn(II) complexes of schiff bases based-on glycine and phenylalanine: Synthesis, magnetic/thermal properties and antimicrobial activity

    Science.gov (United States)

    Sevgi, Fatih; Bagkesici, Ugur; Kursunlu, Ahmed Nuri; Guler, Ersin

    2018-02-01

    Zinc (II), copper (II), nickel (II), cobalt (II) and iron (III) complexes of Schiff bases (LG, LP) derived from 2-hydroxynaphthaldehyde with glycine and phenylalanine were reported and characterized by 1H NMR, 13C NMR, elemental analyses, melting point, FT-IR, magnetic susceptibility and thermal analyses (TGA). TGA data show that iron and cobalt include to the coordinated water and metal:ligand ratio is 1:2 while the complex stoichiometry for Ni (II), Cu (II) and Zn (II) complexes is 1:1. As expected, Ni (II) and Zn (II) complexes are diamagnetic; Cu (II), Co (II) and Fe (III) complexes are paramagnetic character due to a strong ligand of LG and LP. The LG, LP and their metal complexes were screened for their antimicrobial activities against five Gram-positive (Staphylococcus aureus, Methicillin resistant Staphylococcus aureus (MRSA), Bacillus cereus, Streptococcus mutans and Enterococcus faecalis) and three Gram-negative (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa) and one fungi (Candida albicans) by using broth microdilution techniques. The activity data show that ligands and their metal complexes exhibited moderate to good activity against Gram-positive bacteria and fungi.

  5. ZnO/Cu2S/ZnO Multilayer Films: Structure Optimization and Its Detail Data for Applications on Photoelectric and Photocatalytic Properties

    Directory of Open Access Journals (Sweden)

    Zhenxing Wang

    2017-01-01

    Full Text Available Monolayer Cu2S and ZnO, and three kinds of complex films, Cu2S/ZnO, ZnO/Cu2S, and ZnO/Cu2S/ZnO, were deposited on glass substrates by means of radio frequency (RF magnetron sputtering device. The impact of the thickness of ZnO and Cu2S on the whole transmittance, conductivity, and photocatalysis was investigated. The optical and electrical properties of the multilayer were studied by optical spectrometry and four point probes. Numerical simulation of the optical transmittance of the multilayer films has been carried out in order to guide the experimental work. The comprehensive performances of the multilayers as transparent conductive coatings were compared using the figure of merit. Compared with monolithic Cu2S and ZnO films, both the optical transmission property and photocatalytic performance of complex films such as Cu2S/ZnO and ZnO/Cu2S/ZnO change significantly.

  6. Copperton - Areachap Cu-Zn mineralization

    International Nuclear Information System (INIS)

    Theart, H.F.J.

    1985-05-01

    Stratiform massive sulfide deposit at the Prieska Cu-Zn and Areachap mines are situated close to the eastern margin of the Namaqua Province, South Africa, within the Copperton and Jannelsepan Formations. The investigation of the petrology and geochemistry of the Prieska Cu-Zn deposits forms the basis of this study. Borehole core and surface samples were investigated petrographically. Knowledge gained during this investigation was used to select suitable samples for geochemical analysis. Suites of samples were analysed for their major element and some trace element concentrations by wavelength-dispersive X-ray fluorescence spectrometry. Concentrations of some elements in the lanthanide group were determined using the inductively coupled plasma emission spectrometer. Samples were also submitted for analysis by instrumental neutron activation analysis. Determinations of concentrations of U and Pb and isotopic compositions of Pb were done for both whole rock samples and sulfide mineral separates. Major and trace element abundances within different rock types of the Copperton Formation are discussed and compared with those of the Jannelsepan and Hartebeest Pan Formations. The petrogenetic implications of these, the U-Pb isotope systematics and S isotope ratios are used to reconstruct the geological environment of mineralization. 187 refs., 106 figs., 68 tabs

  7. Synthesis, characterization and biological studies of 2-(4-nitrophenylamino-carbonyl)benzoic acid and its complexes with Cr(III), Co(II), Ni(II), Cu(II) and Zn(II)

    International Nuclear Information System (INIS)

    Imran, M; Nazir, S.; Latif, S.; Mahmood, Z.

    2010-01-01

    Cr(III), Co(II), Ni(II), Cu(II) and Zn(II) complexes of 2-(4-Nitrophenyl aminocarbonyl)benzoic acid were synthesized and characterized on the basis of physical, analytical and spectroscopic data. The ligands, as well as its metal complexes were checked for their in-vitro antimicrobial activity against three bacterial strains, Mycobacterium smegmatis, Escherichia coli, Pseudomonas aeuroginosa, and three fungal strains, Nigrospora oryzae, Aspergillus niger and Candida albicans. Disc diffusion method and Tube diffusion test were used for antibacterial and antifungal activities, respectively. The synthesized complexes only show significant antifungal activity but inactive for antibacterial, however, in general, the metal complexes were found to be more active against antimicrobial activities as compared to their un complexed ligand. (author)

  8. Synthesis, spectral characterization thermal stability, antimicrobial studies and biodegradation of starch–thiourea based biodegradable polymeric ligand and its coordination complexes with [Mn(II), Co(II), Ni(II), Cu(II), and Zn(II)] metals

    OpenAIRE

    Nahid Nishat; Ashraf Malik

    2016-01-01

    A biodegradable polymer was synthesized by the modification reaction of polymeric starch with thiourea which is further modified by transition metals, Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). All the polymeric compounds were characterized by (FT-IR) spectroscopy, 1H NMR spectroscopy, 13C NMR spectroscopy, UV–visible spectra, magnetic moment measurements, thermogravimetric analysis (TGA) and antibacterial activities. Polymer complexes of Mn(II), Co(II) and Ni(II) show octahedral geometry, wh...

  9. Synthesis, characterization and biological studies of 2-(4-nitro phenylaminocarbonyl)benzoic acid and its complexes with Cr(III), Co(II), Ni(II), Cu(II) and Zn(II)

    International Nuclear Information System (INIS)

    Aqeel Ashraf, M.; Jamil Maah, M.; Yusuf, I.

    2012-01-01

    Cr(III), Co(II), Ni(II), Cu(II) and Zn(II) salts of 2-(4-nitro phenylaminocarbonyl)benzoic acid were characterized by physical, analytical and spectroscopic studies and checked for their in-vitro antimicrobial activity against three bacterial strains, Mycobacterium smegmatis (Gram +ve), Escherichia coli (Gram -ve), Pseudomonas aeuroginosa (Gram -ve) and three fungal strains, Nigrospora oryzae, Aspergillus niger and Candida albicans. The antimicrobial activities of the metal complexes - were found to be greater than those of 2-(4-nitro phenylaminocarbonyl)benzoic acid alone.

  10. Cr(III,Mn(II,Fe(III,Co(II,Ni(II,Cu(II and Zn(II Complexes with Diisobutyldithiocarbamato Ligand

    Directory of Open Access Journals (Sweden)

    Mohammad Tarique

    2011-01-01

    Full Text Available The synthesis of sulphur and nitrogen containing dithiocarbamato ligand derived from diisobutylamine as well as its coordination compounds with 3d series transition metals is presented. These synthesized compounds were characterized on the basis of elemental analysis, conductometric measurements and IR spectral studies. The analytical data showed the stoichiometry 1:2 and 1:3 for the compounds of the types ML2 {M=Mn(II, Co(II, Ni(II, Cu(II and Zn(II} and M'L3{M'=Cr(III and Fe(III} respectively. The conductometric measurements proved the non-electrolytic behaviour of all the compounds. The bidentate nature of dithiocarbamato moiety was confirmed on the basis of IR spectral data.

  11. Thermal, spectral, magnetic and biological studies of thiosemicarbazones complexes with metal ions: Cu(II), Co(II), Ni(II), Fe(III), Zn(II), Mn(II) and UO2(VI)

    International Nuclear Information System (INIS)

    Mashaly, M.M.; Seleem, H.S.; El-Behairy, M.A.; Habib, H.A.

    2004-01-01

    Thiosemicarbazones ligands, isatin-3-thiosemicarbazone(HIT) and N-acetylisatin-3-thiosemicarbazone (HAIT), which have tridentate ONN coordinating sites were prepared. The complexes of both ligands with Cu(II), Co(II), Ni(II), Fe(III), Zn(II), Mn(II) and UO 2 (VI) ions were isolated. The ligands and their metal complexes were characterized by elemental analysis, IR, UV-Vis and mass spectra, also by conductance, magnetic moment and TG-DSC measurements. All the transition metal complexes have octahedral configurations, except Cu-complexes which have planar geometry and the UO 2 (VI) complexes which have coordination number 8 and may acquire the distorted dodecahedral geometry. Thermal studies explored the possibility of obtaining new complexes. Inversion from octahedral to square-planar configuration occurred upon heating the parent Ni-HIAT complex to form the corresponding pyrolytic product. The antifungal activity against the tested organisms showed that some metal complexes enhanced the activity with respect to the parent ligands. (author)

  12. Preparation of Schiff s base complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) and their spectroscopic, magnetic, thermal, and antifungal studies

    International Nuclear Information System (INIS)

    Parekh, H.M.; Patel, M.N.

    2006-01-01

    The potassium salt of salicylidene-DL-alanine (KHL), bis(benzylidene)ethylenediamine (A 1 ), thiophene-o-carboxaldene-p-toluidine (A 2 ), and its metal complexes of the formula [(M II (L)(A)(H 2 O)] (M=Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II); A = A 1 or A 2 ) are prepared. They are characterized by elemental analysis, magnetic susceptibility measurements, thermogravimetric analysis, and infrared and electronic spectral studies. The electronic spectral and magnetic moment data suggest an octahedral geometry for the complexes. All of these complexes, metal nitrates, fungicides (bavistin and emcarb), and ligands are screened for their antifungal activity against Aspergillus niger, Fusarium oxysporum, and Aspergillus flavus using a plate poison technique. The complexes show higher activity than those of the free ligands, metal nitrate, and the control (DMSO) and moderate activity against bavistin and emcarb [ru

  13. The synthesis and characterization of 1,2-dihydroxyimino-3,6-di-aza-8,9-O-iso-butylidene nonane and its complexes with Ni(II), Cu(II), Zn(II) and Cd(II)

    International Nuclear Information System (INIS)

    Canpolat, E.; Kaya, M.; Gorgulu, A.O.

    2002-01-01

    1,2-dihydroxyimino-3,6-di-aza-8,9-O-iso-butylidene nonane (H 2 L) was synthesized starting from 1,2-O-iso-butylidene-4-aza-6-amino hexane (RNH 2 ) and antichloroglyoxime. Ni(II) and Cu(II) complexes of H 2 L have a metal:ligand ratio 1:2 and the ligand coordinates through two N atoms, as do most of the vic-dioximes. However, Zn(II) and Cd(II) complexes of H 2 L have a metal: ligand ratio 1:1 and one chloride ion and one water molecule are also coordinated to the metal ion. Structures of the ligand and its transition-metal complexes are proposed, according to elemental analysis, IR, 13 C and 1 H NMR spectra, magnetic susceptibility measurements and thermogravimetric analyses (TGA). (author)

  14. Synthesis, investigation and spectroscopic characterization of piroxicam ternary complexes of Fe(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) with glycine and DL-phenylalanine

    Science.gov (United States)

    Mohamed, Gehad G.; El-Gamel, Nadia E. A.

    2004-11-01

    The ternary piroxicam (Pir; 4-hydroxy-2-methyl- N-(2-pyridyl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide) complexes of Fe(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) with various amino acids (AA) such as glycine (Gly) or DL-phenylalanine (PhA) were prepared and characterized by elemental analyses, molar conductance, IR, UV-Vis, magnetic moment, diffuse reflectance and X-ray powder diffraction. The UV-Vis spectra of Pir and the effect of metal chelation on the different interligand transitions are discussed in detailed manner. IR and UV-Vis spectra confirm that Pir behaves as a neutral bidentate ligand coordinated to the metal ions via the pyridine- N and carbonyl group of the amide moiety. Gly molecule acted as a uninegatively monodentate ligand and coordinate to the metal ions through its carboxylic group, in addition PhA acted as a uninegatively bidentate ligand and coordinate to the metal ions through its carboxylic and amino groups. All the chelates have octahedral geometrical structures while Cu(II)- and Zn(II)-ternary chelates with PhA have square planar geometrical structures. The molar conductance data reveal that most of these chelates are non electrolytes, while Fe(III)-Pir-Gly, Co(II)-, Ni(II)-, Cu(II)- and Zn(II)-Pir-PhA cheletes were 1:1 electrolytes. X-ray powder diffraction is used as a new tool to estimate the crystallinity of chelates as well as to elucidate their geometrical structures.

  15. Ternary complexes of Zn(II) and Cu(II) with 1-((2-hydroxynaphthalen-1-yl)methylene)-4-phenylthiosemicarbazide in the presence of heterocyclic bases as auxiliary ligands: Synthesis, spectroscopic and structural characterization and antibacterial activity

    Science.gov (United States)

    Azarkish, Mohammad; Akbari, Alireza; Sedaghat, Tahereh; Simpson, Jim

    2018-03-01

    The new ternary complexes, ZnLL‧ [L = 1-((2-hydroxynaphthalen-1-yl)methylene)-4-phenylthiosemicarbazide and L‧ = imidazole (1), 2, 2‧-bipyridine (2) and 2-methyimidazole (3)], Zn2L2L‧ [L‧ = 4, 4‧-bipy (4)] and CuLL‧ [L‧ = 2, 2‧-bipy (5)] have been synthesized by the reaction of a metal(II) acetate salt with the thiosemicarbazone and in presence of heterocyclic bases as auxiliary ligands. The synthesized compounds were investigated by elemental analysis and IR, 1H NMR, and 13C NMR spectroscopy and complex 5 was structurally characterized by X-ray crystallography. The results indicate the thiosemicarbazone doubly deprotonated and coordinates to metal through the thiolate sulfur, imine nitrogen and phenolic oxygen atoms. The nitrogen atom(s) of the auxiliary ligand complete the coordination sphere. Complex 4 is binuclear with 4, 4‧-bipy acting as a bridging ligand. The structure of 5 is a distorted square pyramid with one of the bipyridine nitrogen atoms in the apical position. This compound creates an inversion dimer in solid state by intermolecular hydrogen bonds of Nsbnd H⋯S type. The in vitro antibacterial activity of the synthesized compounds were evaluated against Gram-positive (B. subtilis and S. aureus) and Gram-negative (P. aeruginosa) bacteria and is compared to that of standard antibacterial drugs. All complexes exhibit good inhibitory effects and are significantly more effective than the parent ligand.

  16. Chemical speciation of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II binary complexes of l-methionine in 1,2-propanediol-water mixtures

    Directory of Open Access Journals (Sweden)

    M. Padma Latha

    2007-04-01

    Full Text Available Chemical speciation of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II complexes of L-methionine in 0.0-60 % v/v 1,2-propanediol-water mixtures maintaining an ionic strength of 0.16 M at 303 K has been studied pH metrically. The active forms of ligand are LH2+, LH and L-. The predominant species detected are ML, MLH, ML2, ML2H, ML2H2 and MLOH. Models containing different numbers of species were refined by using the computer program MINIQUAD 75. The best-fit chemical models were arrived at based on statistical parameters. The trend in variation of complex stability constants with change in the dielectric constant of the medium is explained on the basis of electrostatic and non-electrostatic forces.

  17. Coordination chemistry and bioactivity of Ni2+, Cu2+, and Zn2+ complexes containing a bidentate NS ligand, β-N-phenyldithiocarbazic acid, and the crystal structure of β-hydroxy-β-phenylmethylene α-phenylimine

    International Nuclear Information System (INIS)

    Tarafder, M.T.H.; Ahmed Faizal Shamsuddin; Grouse, Karen A.; Yamin, B.M.; Ali, A.M.; Fun, H.-K.

    2003-07-01

    A bidentate ligand (PhDTCH) with NS donor sequence was prepared from the reaction between carbon disulfide and phenylhydrazine in ethanol. Complexes of this ligand with Ni(II), Cu(II) and Zn(II) were synthesized and characterized by elemental analyses, and various physicochemical techniques. The metal complexes were all four coordinated. In an attempt to resolve the crystal structure of PhDTCH, an ethanolic solution, after leaving for a few days gave bright crystals of PhD6, β-hydroxy-β-phenylmethylene α-phenylimine, the crystal structure of which has been resolved. The crystal packing indicated that it is monoclinic with a space group of P21/n. All of the compounds were tested against different bacteria and fungi, and also against leukemic cell lines. All of the compounds showed weak biological properties compared to standard drugs. (author)

  18. Analysis of CdS/CdTe devices incorporating a ZnTe:Cu/Ti Contact

    International Nuclear Information System (INIS)

    Gessert, T.A.; Asher, S.; Johnston, S.; Young, M.; Dippo, P.; Corwine, C.

    2007-01-01

    High-performance CdS/CdTe photovoltaic devices can be produced using a ZnTe:Cu/Ti back contact deposited onto the CdTe layer. We observe that prolonged exposure of the ZnTe:Cu and Ti sputtering targets to an oxygen-containing plasma significantly reduces device open-circuit voltage and fill factor. High-resolution compositional analysis of these devices reveals that Cu concentration in the CdTe and CdS layers is lower for devices with poor performance. Capacitance-voltage analysis and related numerical simulations indicate that the net acceptor concentration in the CdTe is also lower for devices with poor performance. Photoluminescence analyses of the junction region reveal that the intensity of a luminescent peak associated with a defect complex involving interstitial Cu (Cu i ) and oxygen on Te (O Te ) is reduced in devices with poor performance. Combined with thermodynamic considerations, these results suggest that oxygen incorporation into the ZnTe:Cu sputtering target reduces the ability of sputtered ZnTe:Cu film to diffuse Cu into the CdTe

  19. Cd, Zn, Ni and Cu in the Indian Ocean

    NARCIS (Netherlands)

    Saager, Paul M.; Baar, Hein J.W. de; Howland, Robin J.

    1992-01-01

    Vertical profiles of dissolved Cd, Zn, Ni and Cu in the Northwest Indian Ocean (Arabian Sea) exhibit a nutrient type distribution also observed in other oceans. The area is characterized by strong seasonal upwelling and a broad oxygen minimum zone in intermediate waters. However, neither Cd, Zn, Ni

  20. Electrodeposition of Zn and Cu–Zn alloy from ZnO/CuO precursors in deep eutectic solvent

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xueliang [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Zou, Xingli, E-mail: xinglizou@shu.edu.cn [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Lu, Xionggang, E-mail: luxg@shu.edu.cn [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Lu, Changyuan; Cheng, Hongwei; Xu, Qian [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Zhou, Zhongfu [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Institute of Mathematics and Physics, Aberystwyth University, Aberystwyth SY23 3BZ (United Kingdom)

    2016-11-01

    Graphical abstract: Micro/nanostructured Zn and Cu–Zn alloy films have been electrodeposited directly from ZnO/CuO precursors in ChCl/urea-based DES, the typical nucleation-growth mechanism and the micro/nanostructures-formation process are determined. Display Omitted - Highlights: • Micro/nanostructured Zn films have been electrodeposited directly from ZnO precursor in deep eutectic solvent (DES). • The morphology of the Zn electrodeposits depends on the cathodic potential and temperature. • The electrodeposited Zn films exhibit homogeneous morphologies with controllable particle sizes and improved corrosion resistance. • Cu–Zn alloy films have also been electrodeposited directly from their metal oxides precursors in DES. - Abstract: The electrodeposition of Zn and Cu–Zn alloy has been investigated in choline chloride (ChCl)/urea (1:2 molar ratio) based deep eutectic solvent (DES). Cyclic voltammetry study demonstrates that the reduction of Zn(II) to Zn is a diffusion-controlled quasi-reversible, one-step, two electrons transfer process. Chronoamperometric investigation indicates that the electrodeposition of Zn on a Cu electrode typically involves three-dimensional instantaneous nucleation with diffusion-controlled growth process. Micro/nanostructured Zn films can be obtained by controlling the electrodeposition potential and temperature. The electrodeposited Zn crystals preferentially orient parallel to the (101) plane. The Zn films electrodeposited under more positive potentials and low temperatures exhibit improved corrosion resistance in 3 wt% NaCl solution. In addition, Cu–Zn alloy films have also been electrodeposited directly from CuO–ZnO precursors in ChCl/urea-based DES. The XRD analysis indicates that the phase composition of the electrodeposited Cu–Zn alloy depends on the electrodeposition potential.

  1. Studies on coordination chemistry and bioactivity of complexes of a bidentate oxygen-oxygen donor ligand, 1,2-dibenzoylhydrazine, with Cr3+, Co2+, Ni2+, Cu2+ and Zn2+ Ions

    International Nuclear Information System (INIS)

    Tarafder, M.T.H.; Lai Wee Wong; Crouse, Karen A.; Ali, A.M.; Yamin, B.M.; Fun, H.-K.

    2003-08-01

    A new bidentate ligand, 1,2-dibenzoylhydrazine (DBHz), with OO donor sequences, was prepared. Several complexes of DBHz containing Cr(JJI), Fe(UI), Co(U), Ni(JJ), Cu(II) and Zn(TJ) ions have been synthesized and characterized by CHN analyses, IR, molar conductivity and UV/Visible spectroscopic studies. All of the compounds were tested for their antibacterial, antifungal and anticancer properties. DBHz was very effective against Pseudomonas aeruginosa, Bacillus subtilis mutant and Bacillus subtilis wild type bacteria. It was also effective against Saccaromyces cereiviceae, Candida albicans, Candida albicans lypolytica and Aspergillus ochraceous fungi. The free ligand, DBHz, in particular, was strongly active against colon cancer cell lines (HT-29), with a CD 50 value of 2.5 /μg/ml. (author)

  2. Cyclotron production of {sup 61}Cu using natural Zn and enriched {sup 64}Zn targets

    Energy Technology Data Exchange (ETDEWEB)

    Asad, A. H.; Smith, S. V.; Chan, S.; Jeffery, C. M.; Morandeau, L.; Price, R. I. [RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth, Australia, Imaging and Applied Physics, Curtin University, Perth, Australia, and Center of Excellence in Anti-matter Matter Studies, Australian National University, Can (Australia); Brookhaven National Laboratory, Upton, NY (United States) and Center of Excellence in Anti-matter Matter Studies, Australian National University, Canberra (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); Center of Excellence in Anti-matter Matter Studies, Australian National University, Canberra, Australia, and Chemistry, University of Western Australia, Pe (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth, Australia and Physics, University of Western Australia, Perth (Australia)

    2012-12-19

    Copper-61 ({sup 61}Cu) shares with {sup 64}Cu certain advantages for PET diagnostic imaging, but has a shorter half-life (3.4hr vs. 12.7hr) and a greater probability of positron production per disintegration (61% vs. 17.9%). One important application is for in vivo imaging of hypoxic tissue. In this study {sup 61}Cu was produced using the {sup 64}Zn(p,{alpha}){sup 61}Cu reaction on natural Zn or enriched {sup 64}Zn targets. The enriched {sup 64}Zn (99.82%) was electroplated onto high purity gold or silver foils or onto thin Al discs. A typical target bombardment used 30{mu}A; at 11.7, 14.5 or 17.6MeV over 30-60min. The {sup 61}Cu (radiochemical purity of >95%) was separated using a combination of cation and anion exchange columns. The {sup 64}Zn target material was recovered after each run, for re-use. In a direct comparison with enriched {sup 64}Zn-target results, {sup 61}Cu production using the cheaper {sup nat}Zn target proved to be an effective alternative.

  3. Copper doping of ZnO crystals by transmutation of {sup 64}Zn to {sup 65}Cu: An electron paramagnetic resonance and gamma spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Recker, M. C.; McClory, J. W., E-mail: John.McClory@afit.edu; Holston, M. S.; Golden, E. M.; Giles, N. C. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (United States); Halliburton, L. E. [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-06-28

    Transmutation of {sup 64}Zn to {sup 65}Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the {sup 65}Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of {sup 64}Zn nuclei to {sup 65}Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu{sup 2+} ions (where {sup 63}Cu and {sup 65}Cu hyperfine lines are easily resolved). A spectrum from isolated Cu{sup 2+} (3d{sup 9}) ions acquired after the neutron irradiation showed only hyperfine lines from {sup 65}Cu nuclei. The absence of {sup 63}Cu lines in this Cu{sup 2+} spectrum left no doubt that the observed {sup 65}Cu signals were due to transmuted {sup 65}Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu{sup +}-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu{sup +}-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

  4. Copper doping of ZnO crystals by transmutation of 64Zn to 65Cu: An electron paramagnetic resonance and gamma spectroscopy study

    International Nuclear Information System (INIS)

    Recker, M. C.; McClory, J. W.; Holston, M. S.; Golden, E. M.; Giles, N. C.; Halliburton, L. E.

    2014-01-01

    Transmutation of 64 Zn to 65 Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the 65 Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of 64 Zn nuclei to 65 Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu 2+ ions (where 63 Cu and 65 Cu hyperfine lines are easily resolved). A spectrum from isolated Cu 2+ (3d 9 ) ions acquired after the neutron irradiation showed only hyperfine lines from 65 Cu nuclei. The absence of 63 Cu lines in this Cu 2+ spectrum left no doubt that the observed 65 Cu signals were due to transmuted 65 Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu + -H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu + -H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

  5. Copper doping of ZnO crystals by transmutation of 64Zn to 65Cu: An electron paramagnetic resonance and gamma spectroscopy study

    Science.gov (United States)

    Recker, M. C.; McClory, J. W.; Holston, M. S.; Golden, E. M.; Giles, N. C.; Halliburton, L. E.

    2014-06-01

    Transmutation of 64Zn to 65Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the 65Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of 64Zn nuclei to 65Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu2+ ions (where 63Cu and 65Cu hyperfine lines are easily resolved). A spectrum from isolated Cu2+ (3d9) ions acquired after the neutron irradiation showed only hyperfine lines from 65Cu nuclei. The absence of 63Cu lines in this Cu2+ spectrum left no doubt that the observed 65Cu signals were due to transmuted 65Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu+-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu+-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

  6. Exploring the activated state of Cu/ZnO-Zn, a model catalyst for methanol synthesis

    NARCIS (Netherlands)

    Batyrev, E.D.; Shiju, N.R.; Rothenberg, G.

    2012-01-01

    The interaction of Cu clusters with ZnO(0001)-Zn terminated crystal faces is studied after reduction at high temperatures by a combination of scanning tunneling microscopy, scanning tunneling spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermal desorption spectroscopy. We find that tiny

  7. Punicalagin Green Functionalized Cu/Cu2O/ZnO/CuO Nanocomposite for Potential Electrochemical Transducer and Catalyst

    Science.gov (United States)

    Fuku, X.; Kaviyarasu, K.; Matinise, N.; Maaza, M.

    2016-09-01

    A novel ternary Punica granatum L-Cu/Cu2O/CuO/ZnO nanocomposite was successfully synthesised via green route. In this work, we demonstrate that the green synthesis of metal oxides is more viable and facile compare to other methods, i.e., physical and chemical routes while presenting a potential electrode for energy applications. The prepared nanocomposite was characterised by both microscopic and spectroscopic techniques. High-resolution scanning electron microscopy (HRSEM) and X-ray diffraction (XRD) techniques revealed different transitional phases with an average nanocrystallite size of 29-20 mm. It was observed that the nanocomposites changed from amorphous-slightly crystalline Cu/Cu2O to polycrystalline Cu/Cu2O/CuO/ZnO at different calcination temperatures (room temperature-RT- 600 °C). The Cu/Cu2O/ZnO/CuO metal oxides proved to be highly crystalline and showed irregularly distributed particles with different sizes. Meanwhile, Fourier transform infrared (FTIR) spectroscopy confirmed the purity while together with ultraviolet-visible (UV-Vis) spectroscopy proved the proposed mechanism of the synthesised nanocomposite. UV-Vis showed improved catalytic activity of the prepared metal oxides, evident by narrow band gap energy. The redox and electrochemical properties of the prepared nanocomposite were achieved by cyclic voltammetry (CV), electrochemical impedance (EIS) and galvanostatic charge-discharge (GCD). The maximum specific capacitance ( C s) was calculated to be 241 F g-1 at 50 mV s-1 for Cu/Cu2O/CuO/ZnO nanoplatelets structured electrode. Moreover, all the CuO nanostructures reveal better power performance, excellent rate as well as long term cycling stability. Such a study will encourages a new design for a wide spectrum of materials for smart electronic device applications.

  8. Molecular characterization of two CuZn-superoxide dismutases in a sea anemone.

    Science.gov (United States)

    Plantivaux, Amandine; Furla, Paola; Zoccola, Didier; Garello, Ginette; Forcioli, Didier; Richier, Sophie; Merle, Pierre-Laurent; Tambutté, Eric; Tambutté, Sylvie; Allemand, Denis

    2004-10-15

    Cnidarians living in symbiosis with photosynthetic cells--called zooxanthellae--are submitted to high oxygen levels generated by photosynthesis. To cope with this hyperoxic state, symbiotic cnidarians present a high diversity of superoxide dismutases (SOD) isoforms. To understand better the mechanism of resistance of cnidarian hosts to hyperoxia, we studied copper- and zinc-containing SOD (CuZnSOD) from Anemonia viridis, a temperate symbiotic sea anemone. We cloned two CuZnSOD genes that we call AvCuZnSODa and AvCuZnSODb. Their molecular analysis suggests that the AvCuZnSODa transcript encodes an extracellular form of CuZnSOD, whereas the AvCuZnSODb transcript encodes an intracellular form. Using in situ hybridization, we showed that both AvCuZnSODa and AvCuZnSODb transcripts are expressed in the endodermal and ectodermal cells of the sea anemone, but not in the zooxanthellae. The genomic flanking sequences of AvCuZnSODa and AvCuZnSODb revealed different putative binding sites for transcription factors, suggesting different modes of regulation for the two genes. This study represents a first step in the understanding of the molecular mechanisms of host animal resistance to permanent hyperoxia status resulting from the photosynthetic symbiosis. Moreover, AvCuZnSODa and AvCuZnSODb are the first SODs cloned from a diploblastic animal, contributing to the evolutionary understanding of SODs.

  9. ZnO/Cu/ZnO multilayer films: Structure optimization and investigation on photoelectric properties

    International Nuclear Information System (INIS)

    Liu Xiaoyu; Li Yingai; Liu Shi; Wu Honglin; Cui Haining

    2012-01-01

    A series of ZnO/Cu/ZnO multilayer films has been fabricated from zinc and copper metallic targets by simultaneous RF and DC magnetron sputtering. Numerical simulation of the optical properties of the multilayer films has been carried out in order to guide the experimental work. The influences of the ZnO and Cu layer thicknesses, and of O 2 /Ar ratio on the photoelectric and structural properties of the films were investigated. The optical and electrical properties of the multilayers were studied by optical spectrometry and four point probe measurements, respectively. The structural properties were investigated using X-ray diffraction. The performance of the multilayers as transparent conducting coatings was compared using a figure of merit. In experiments, the thickness of the ZnO layers was varied between 4 and 70 nm and those of Cu were between 8 and 37 nm. The O 2 /Ar ratios range from 1:5 to 2:1. Low sheet resistance and high transmittance were obtained when the film was prepared using an O 2 /Ar ratio of 1:4 and a thickness of ZnO (60 nm)/Cu (15 nm)/ZnO (60 nm). - Highlights: ► ZnO/Cu/ZnO films were fabricated from zinc and copper targets by sputtering. ► Transmittance reaches maximum when top and bottom ZnO thicknesses are nearly equal. ► Sheet resistance increases with increasing ZnO layer thickness. ► Variation in sheet resistance with oxygen/argon ratio is due to interface effect.

  10. Synthesis, spectroscopic and DNA binding ability of CoII, NiII, CuII and ZnII complexes of Schiff base ligand (E)-1-(((1H-benzo[d]imidazol-2-yl)methylimino)methyl)naphthalen-2-ol. X-ray crystal structure determination of cobalt (II) complex.

    Science.gov (United States)

    Yarkandi, Naeema H; El-Ghamry, Hoda A; Gaber, Mohamed

    2017-06-01

    A novel Schiff base ligand, (E)-1-(((1H-benzo[d]imidazol-2-yl)methylimino)methyl)naphthalen-2-ol (HL), has been designed and synthesized in addition to its metal chelates [Co(L) 2 ]·l2H 2 O, [Ni(L)Cl·(H 2 O) 2 ].5H 2 O, [Cu(L)Cl] and [Zn(L)(CH 3 COO)]. The structures of the isolated compounds have been confirmed and identified by means of different spectral and physicochemical techniques including CHN analysis, 1 H & 13 C NMR, mass spectral analysis, molar conductivity measurement, UV-Vis, infrared, magnetic moment in addition to TGA technique. The infrared spectral results ascertained that the ligand acts as monobasic tridentate binding to the metal centers via deprotonated hydroxyl oxygen, azomethine and imidazole nitrogen atoms. The UV-Vis, magnetic susceptibility and molar conductivity data implied octahedral geometry for Co(II) & Ni(II) complexes, tetrahedral for Zn(II) complex and square planar for Cu(II) complex. X-ray structural analysis of Co(II) complex 1 has been reported and discussed. Moreover, the type of interaction between the ligand & its complexes towards salmon sperm DNA (SS-DNA) has been examined by the measurement of absorption spectra and viscosity which confirmed that the ligand and its complexes interact with DNA via intercalation interaction as concluded from the values of binding constants (K b ). Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Elastocaloric effect in CuAlZn and CuAlMn shape memory alloys under compression

    OpenAIRE

    Qian, Suxin; Geng, Yunlong; Wang, Yi; Pillsbury, Thomas E.; Hada, Yoshiharu; Yamaguchi, Yuki; Fujimoto, Kenjiro; Hwang, Yunho; Radermacher, Reinhard; Cui, Jun; Yuki, Yoji; Toyotake, Koutaro; Takeuchi, Ichiro

    2016-01-01

    This paper reports the elastocaloric effect of two Cu-based shape memory alloys: Cu68Al16Zn16 (CuAlZn) and Cu73Al15Mn12 (CuAlMn), under compression at ambient temperature. The compression tests were conducted at two different rates to approach isothermal and adiabatic conditions. Upon unloading at a strain rate of 0.1 s−1 (adiabatic condition) from 4% strain, the highest adiabatic temperature changes (ΔTad) of 4.0 K for CuAlZn and 3.9 K for CuAlMn were obtained. The maximum stress and hystere...

  12. Synthesis, spectral characterization, theoretical, antimicrobial, DNA interaction and in vitro anticancer studies of Cu(II and Zn(II complexes with pyrimidine-morpholine based Schiff base ligand

    Directory of Open Access Journals (Sweden)

    M. Sankarganesh

    2018-05-01

    Full Text Available Novel Cu(II (1 and Zn(II (2 complexes with 4-(1-(4-morpholinophenylethylideneaminopyrimidine-5-carbonitrile (L have been synthesized and characterized by various spectroscopic and analytical techniques. DFT (density functional theory studies result confirms that, LMCT mechanism have been done between L and M(II ions. The antimicrobial studies indicate that the ligand L and complexes 1 & 2 exhibit higher activity against the E. coli bacteria and C. albicans fungi. The groove binding mode of ligand L and complexes 1 & 2 with CT-DNA have been confirmed by electronic absorption, competitive binding, viscometric and cyclic voltammetric studies. The electronic absorption titration of ligand L and complexes 1 & 2 with DNA have been carried out in different buffer solutions (pH 4.0, 7.0 & 10.0. The Kb values of ligand L and complexes 1 & 2 are higher in acidic buffer at pH 4.0 (Kb = 2.42 × 105, L; 2.8 × 105, 1; 2.65 × 105, 2 and the results revealed that, the interaction of synthesized compounds with DNA were higher in the acidic medium than basic and neutral medium. Furthermore, CT-DNA cleavage studies of ligand L and complexes 1 & 2 have been studied. The in vitro anticancer activities results show that complexes 1 & 2 have moderate cytotoxicity against cancer cell lines and low toxicity on normal cell line than ligand L. Keywords: Pyrimidine, Morpholine, DFT, Antimicrobial, DNA binding, Anticancer studies

  13. Facile synthesis of Cu/tetrapod-like ZnO whisker compounds with enhanced photocatalytic properties

    Science.gov (United States)

    Liu, Hong; Liu, Huarong; Fan, Ximei

    2017-09-01

    Cu/tetrapod-like ZnO whisker (T-ZnOw) compounds were successfully synthesized using N2H4 \\cdot H2O as a reducing agent by a simple reduction method without any insert gas at room temperature. The crystal phase composition and morphology of the as-prepared samples were investigated by XRD, SEM and FESEM tests. The photocatalytic property of the as-prepared samples was detected by the degradation of methyl orange (MO) aqueous solution under UV irradiation. It can be found that Cu nanoparticles (CuNPs) dispersed on the surface of T-ZnOw increased with the increasing of Cu/Zn molar ratios (Cu/Zn MRs), and an octahedral structure of CuNPs was obtained when the sample was prepared with less than and equal to 7.30% Cu/Zn MR, but tended to a spherical or nanorod structure of CuNPs densely arranged on the surface of T-ZnOw, which is prepared by Cu/Zn MRs up to 22.00%. All the compounds exhibited excellent photocatalytic activity in decomposing of MO than T-ZnOw, the photocatalytic property of the samples increased with the increasing of Cu/Zn MRs up to 7.30%, while it decreases when further increasing the Cu/Zn MRs. The Schottky barrier of the Cu/T-ZnOw compound can effectively capture photoinduced electrons from the interface and enhanced the photocatalytic property of T-ZnOw.

  14. Electrodeposition mechanism of quaternary compounds Cu2ZnSnS4: Effect of the additives

    Science.gov (United States)

    Tang, Aiyue; Li, Zhilin; Wang, Feng; Dou, Meiling; Liu, Jingjun; Ji, Jing; Song, Ye

    2018-01-01

    The electrodeposition mechanism of pure phase Cu2ZnSnS4 (CZTS) thin film with subsequent annealing was investigated in detail. An electrolyte design principle of quaternary compounds was proposed. The complex ions of Cu(H2C6H5O7)+, Cu2(C6H5O7)+, Zn(C4H5O6)+, Sn(H2C6H5O7)+ and Sn2(C6H5O7)+, which influenced the reduction process and played important roles in co-deposition, were identified by UV spectra. Electrochemical studies indicated that trisodium citrate and tartaric acid could narrow the co-deposition potential range of the four elements to -0.8 V to -1.2 V (vs. SCE). The cause was the synergetic effect that trisodium citrate inhibited the reduction of Cu2+ and Sn2+ and tartaric acid promoted the reduction of Zn2+. The reduction of S2O32- was mainly attributed to the induction effect of the metallic ions, and the H+ dissociated from tartaric acid could also promote the cathode process of S2O32-. The reaction mechanism could be summarized as the following steps: (I) Cu(H2C6H5O7)+, Cu2(C6H5O7)+ → Cu, Sn(H2C6H5O7)+, Sn2(C6H5O7)+ → Sn, Zn(C4H5O6)+ → Zn; (II) the desorption of (H2C6H5O7)- and (C6H5O7)-, and the reduction of S2O32- induced by metallic ions and H+. The mechanism studies provided a path of electrolyte design for multicomponent compounds.

  15. Study of interfacial reactions in Sn-3.5Ag-3.0Bi and Sn-8.0Zn-3.0Bi sandwich structure solder joint with Ni(P)/Cu metallization on Cu substrate

    International Nuclear Information System (INIS)

    Sun, Peng; Andersson, Cristina; Wei, Xicheng; Cheng, Zhaonian; Shangguan, Dongkai; Liu, Johan

    2007-01-01

    In this paper, the coupling effect in Sn-3.5Ag-3.0Bi and Sn-8.0Zn-3.0Bi solder joint with sandwich structure by long time reflow soldering was studied. It was found that the interfacial compound at the Cu substrate was binary Cu-Sn compound in Sn-Ag-Bi solder joint and Cu 5 Zn 8 phase in Sn-Zn-Bi solder joint. The thickness of the Cu-Zn compound layer formed at the Cu substrate was greater than or equal to that of Cu-Sn compound layer, although the reflow soldering temperature of Sn-Zn-Bi (240 o C) was lower than that of Sn-Ag-Bi (250 o C). The stable Cu-Zn compound was the absolute preferential phase in the interfacial layer between Sn-Zn-Bi and the Cu substrate. The ternary (Cu, Ni) 6 Sn 5 compound was formed at the Sn-Ag-Bi/Ni(P)-Cu metallization interface, and a complex alloy Sn-Ni-Cu-Zn was formed at the Sn-Zn-Bi/Ni(P)-Cu metallization interface. It was noted that Cu atoms could diffuse from the Cu substrate through the solder matrix to the Ni(P)-Cu metallization within 1 min reflow soldering time for both solder systems, indicating that just 30 s was long enough for Cu to go through 250 μm diffusion length in the Sn-Ag-Bi solder joint at 250 o C. The coupling effect between Ni(P)/Cu metallization and Cu substrate was confirmed as the type of IMCs at Ni(P) layer had been changed from Ni-Sn system to Cu-Sn system apparently by the diffusion effect of Cu atoms. The (Cu, Ni) 6 Sn 5 layer at the Ni(P)/Cu metallization grew significantly and its thickness was even greater than that of the Cu-Sn compound on the opposite side, however the growth of the complex alloy including Sn, Ni, Cu and Zn on the Ni(P)/Cu metallization was suppressed

  16. Comparison of trace element contamination levels (Cu, Zn, Fe, Cd ...

    African Journals Online (AJOL)

    Comparison of trace element contamination levels (Cu, Zn, Fe, Cd and Pb) in the soft tissues of the gastropods Tympanotonus fuscatus fuscatus and Tf radula collected in the Ebrié Lagoon (Côte d'Ivoire): Evidence of the risks linked to linked to lead and.

  17. Electrodeposited Cu2ZnSnS4 thin films

    CSIR Research Space (South Africa)

    Valdes, M

    2014-05-01

    Full Text Available Cu(sub2)ZnSnS(sub4)(CZTS) thin films have been prepared using Electrochemical Atomic Layer Deposition (EC-ALD)and also by one-step conventional constant potential electrodeposition. Optimal deposition conditionswere investigated using cyclic...

  18. Comparison of trace element contamination levels (Cu, Zn, Fe, Cd ...

    African Journals Online (AJOL)

    SERVER

    2008-03-18

    Mar 18, 2008 ... Chemical analysis of the trace elements in the soft tissues. The trace elements of interest (Cu, Zn, Fe, Pb, Cd) were then determined in the digested solutions, using Thermoelemental type. M6 brand of an atomic absorption Spectrometer equipped with a flame operated atomisation system and a deuterium ...

  19. CuZn Alloy- Based Electrocatalyst for CO2 Reduction

    KAUST Repository

    Alazmi, Amira

    2014-01-01

    , especially when the electronic energy is derived from renewable energies, such as solar, wind, geo-thermal and tidal. To achieve this goal, the development of an efficient electrocatalyst for CO2 reduction is essential. In this thesis, studies on CuZn alloys

  20. At the Nexus of Antibiotics and Metals: The Impact of Cu and Zn on Antibiotic Activity and Resistance.

    Science.gov (United States)

    Poole, Keith

    2017-10-01

    Environmental influences on antibiotic activity and resistance can wreak havoc with in vivo antibiotic efficacy and, ultimately, antimicrobial chemotherapy. In nature, bacteria encounter a variety of metal ions, particularly copper (Cu) and zinc (Zn), as contaminants in soil and water, as feed additives in agriculture, as clinically-used antimicrobials, and as components of human antibacterial responses. Importantly, there is a growing body of evidence for Cu/Zn driving antibiotic resistance development in metal-exposed bacteria, owing to metal selection of genetic elements harbouring both metal and antibiotic resistance genes, and metal recruitment of antibiotic resistance mechanisms. Many classes of antibiotics also form complexes with metal cations, including Cu and Zn, and this can hinder (or enhance) antibiotic activity. This review highlights the ways in which Cu/Zn influence antibiotic resistance development and antibiotic activity, and in so doing impact in vivo antibiotic efficacy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Tuning the emission of aqueous Cu:ZnSe quantum dots to yellow light window

    International Nuclear Information System (INIS)

    Wang, Chunlei; Hu, Zhiyang; Xu, Shuhong; Wang, Yanbin; Zhao, Zengxia; Wang, Zhuyuan; Cui, Yiping

    2015-01-01

    Synthesis of internally doped Cu:ZnSe QDs in an aqueous solution still suffers from narrow tunable emissions from the blue to green light window. In this work, we extended the emission window of aqueous Cu:ZnSe QDs to the yellow light window. Our results show that high solution pH, multiple injections of Zn precursors, and nucleation doping strategy are three key factors for preparing yellow emitted Cu:ZnSe QDs. All these factors can depress the reactivity of CuSe nuclei and Zn monomers, promoting ZnSe growth outside CuSe nuclei rather than form ZnSe nuclei separately. With increased ZnSe QD size, the conduction band and nearby trap state energy levels shift to higher energy sites, causing Cu:ZnSe QDs to have a much longer emission. (paper)

  2. CuZn Alloy- Based Electrocatalyst for CO2 Reduction

    KAUST Repository

    Alazmi, Amira

    2014-06-01

    ABSTRACT CuZn Alloy- Based Electrocatalyst for CO2 Reduction Amira Alazmi Carbon dioxide (CO2) is one of the major greenhouse gases and its emission is a significant threat to global economy and sustainability. Efficient CO2 conversion leads to utilization of CO2 as a carbon feedstock, but activating the most stable carbon-based molecule, CO2, is a challenging task. Electrochemical conversion of CO2 is considered to be the beneficial approach to generate carbon-containing fuels directly from CO2, especially when the electronic energy is derived from renewable energies, such as solar, wind, geo-thermal and tidal. To achieve this goal, the development of an efficient electrocatalyst for CO2 reduction is essential. In this thesis, studies on CuZn alloys with heat treatments at different temperatures have been evaluated as electrocatalysts for CO2 reduction. It was found that the catalytic activity of these electrodes was strongly dependent on the thermal oxidation temperature before their use for electrochemical measurements. The polycrystalline CuZn electrode without thermal treatment shows the Faradaic efficiency for CO formation of only 30% at applied potential ~−1.0 V vs. RHE with current density of ~−2.55 mA cm−2. In contrast, the reduction of oxide-based CuZn alloy electrode exhibits 65% Faradaic efficiency for CO at lower applied potential about −1.0 V vs. RHE with current density of −2.55 mA cm−2. Furthermore, stable activity was achieved over several hours of the reduction reaction at the modified electrodes. Based on electrokinetic studies, this improvement could be attributed to further stabilization of the CO2•− on the oxide-based Cu-Zn alloy surface.

  3. Organic/inorganic nanocomposites of ZnO/CuO/chitosan with improved properties

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xingfa, E-mail: xingfamazju@aliyun.com [School of Environmental and Material Engineering, Center of Advanced Functional Materials, Yantai University, Yantai, 264005 (China); State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027 (China); Zhang, Bo; Cong, Qin; He, Xiaochun; Gao, Mingjun [School of Environmental and Material Engineering, Center of Advanced Functional Materials, Yantai University, Yantai, 264005 (China); Li, Guang [National Laboratory of Industrial Control Technology, Institute of Cyber-Systems and Control, Zhejiang University, Hangzhou, 310027 (China)

    2016-08-01

    To extend the visible light response of ZnO, ZnO/CuO heterostructured nanocomposite was synthesized by a hydrothermal approach. At the same time, chitosan (Ch) is considered as a very promising natural polymer. It holds not only abundant resource and low cost, but also has excellent adsorption properties to a broad range of organic pollutants and some heavy metal ions. To improve the adsorption properties of ZnO/CuO nanocomposite, ZnO/CuO/chitosan organic-inorganic composites were prepared with precipitation method. The as-prepared nanocomposites were characterized by TEM (Transmission electron microscopy), SAED pattern (Selected Area Electron Diffraction), SEM (scanning electron microscopy), UV–Vis (Ultraviolet–visible spectroscopy), PL (Photoluminescence), XRD (X-ray diffraction), TGA (Thermo Gravimetric Analyzer), Fourier transform infrared spectroscopy spectra (FTIR) et al. To examine the surface and interface properties of nanocomposites, chemical prototype sensor arrays were constructed based on ZnO, ZnO/CuO, ZnO/Cu{sub 2}O, ZnO/CuO/chitosan, ZnO/Cu{sub 2}O/chitosan nanocomposites and QCM (quartz crystal microbalance) arrays devices. The adsorption response behaviors of the sensor arrays to some typical volatile compounds were examined under similar conditions. The results indicated that with comparison to ZnO nanostructure, the ZnO/CuO nanocomposite exhibited enhanced adsorption properties to some typical volatile compounds greatly, and the adsorption properties of ZnO/CuO/chitosan are much better than that of ZnO/CuO nanocomposite. The adsorption of ZnO/CuO system is super to that of ZnO/Cu{sub 2}O. Therefore, ZnO/CuO/chitosan nanocomposite not only showed broadening visible light response, but also possessed of excellent adsorption properties, and has good potential applications in photocatalysts, chemical sensors, biosensors, self-cleaning coating fields et al. - Highlights: • ZnO/CuO nanocomposites exhibited good response in near whole visible

  4. Colloidal synthesis of Cu-ZnO and Cu@CuNi-ZnO hybrid nanocrystals with controlled morphologies and multifunctional properties

    Science.gov (United States)

    Zeng, Deqian; Gong, Pingyun; Chen, Yuanzhi; Zhang, Qinfu; Xie, Qingshui; Peng, Dong-Liang

    2016-06-01

    Metal-semiconductor hybrid nanocrystals have received extensive attention owing to their multiple functionalities which can find wide technological applications. The utilization of low-cost non-noble metals to construct novel metal-semiconductor hybrid nanocrystals is important and meaningful for their large-scale applications. In this study, a facile solution approach is developed for the synthesis of Cu-ZnO hybrid nanocrystals with well-controlled morphologies, including nanomultipods, core-shell nanoparticles, nanopyramids and core-shell nanowires. In the synthetic strategy, Cu nanocrystals formed in situ serve as seeds for the heterogeneous nucleation and growth of ZnO, and it eventually forms various Cu-ZnO hetero-nanostructures under different reaction conditions. These hybrid nanocrystals possess well-defined and stable heterostructure junctions. The ultraviolet-visible-near infrared spectra reveal morphology-dependent surface plasmon resonance absorption of Cu and the band gap absorption of ZnO. Furthermore, we construct a novel Cu@CuNi-ZnO ternary hetero-nanostructure by incorporating the magnetic metal Ni into the pre-synthesized colloidal Cu nanocrystals. Such hybrid nanocrystals possess a magnetic Cu-Ni intermediate layer between the ZnO shell and the Cu core, and exhibit ferromagnetic/superparamagnetic properties which expand their functionalities. Finally, enhanced photocatalytic activities are observed in the as-prepared non-noble metal-ZnO hybrid nanocrystals. This study not only provides an economical way to prepare high-quality morphology-controlled Cu-ZnO hybrid nanocrystals for potential applications in the fields of photocatalysis and photovoltaic devices, but also opens up new opportunities in designing ternary non-noble metal-semiconductor hybrid nanocrystals with multifunctionalities.Metal-semiconductor hybrid nanocrystals have received extensive attention owing to their multiple functionalities which can find wide technological applications

  5. Synthesis, spectroscopic and DNA binding ability of Co{sup II}, Ni{sup II}, Cu{sup II} and Zn{sup II} complexes of Schiff base ligand (E)-1-(((1H-benzo[d]imidazol-2-yl)methylimino)methyl)naphthalen-2-ol. X-ray crystal structure determination of cobalt (II) complex

    Energy Technology Data Exchange (ETDEWEB)

    Yarkandi, Naeema H. [Chemistry Department, Faculty of Applied Science, Umm Al–Qura University, Makkah (Saudi Arabia); El-Ghamry, Hoda A., E-mail: helghamrymo@yahoo.com [Chemistry Department, Faculty of Applied Science, Umm Al–Qura University, Makkah (Saudi Arabia); Chemistry Department, Faculty of Science, Tanta University, Tanta (Egypt); Gaber, Mohamed [Chemistry Department, Faculty of Science, Tanta University, Tanta (Egypt)

    2017-06-01

    A novel Schiff base ligand, (E)-1-(((1H-benzo[d]imidazol-2-yl)methylimino)methyl)naphthalen-2-ol (HL), has been designed and synthesized in addition to its metal chelates [Co(L){sub 2}]·l2H{sub 2}O, [Ni(L)Cl·(H{sub 2}O){sub 2}].5H{sub 2}O, [Cu(L)Cl] and [Zn(L)(CH{sub 3}COO)]. The structures of the isolated compounds have been confirmed and identified by means of different spectral and physicochemical techniques including CHN analysis, {sup 1}H &{sup 13}C NMR, mass spectral analysis, molar conductivity measurement, UV–Vis, infrared, magnetic moment in addition to TGA technique. The infrared spectral results ascertained that the ligand acts as monobasic tridentate binding to the metal centers via deprotonated hydroxyl oxygen, azomethine and imidazole nitrogen atoms. The UV–Vis, magnetic susceptibility and molar conductivity data implied octahedral geometry for Co(II) & Ni(II) complexes, tetrahedral for Zn(II) complex and square planar for Cu(II) complex. X-ray structural analysis of Co(II) complex 1 has been reported and discussed. Moreover, the type of interaction between the ligand & its complexes towards salmon sperm DNA (SS-DNA) has been examined by the measurement of absorption spectra and viscosity which confirmed that the ligand and its complexes interact with DNA via intercalation interaction as concluded from the values of binding constants (K{sub b}). - Highlights: • Synthesis of Co{sup II}, Ni{sup II}, Cu{sup II} and Zn{sup II} complexes of the Schiff base ligand based on 2-(aminomethyl)benzimidazole moiety. • The constitutions and structures of the ligand and complexes were elucidated. • Molecular structure of Co{sup II} complex was confirmed by single crystal X-ray diffraction method. • The ligand and its complexes interact with SS-DNA via intercalation mods.

  6. Leaching of hydrophobic Cu and Zn from discarded marine antifouling paint residues: Evidence for transchelation of metal pyrithiones

    International Nuclear Information System (INIS)

    Holmes, Luke; Turner, Andrew

    2009-01-01

    Leaching of Cu and Zn from a composite of discarded antifouling paint residues ([Cu] = 288 mg g -1 ; [Zn] = 96 mg g -1 ) into natural sea water has been studied over a period of 75 h. Total Cu and Zn were released according to a pseudo first-order reaction, with rate constants on the order of 0.3 and 2.5 (mg L -1 ) -1 h -1 , respectively, and final concentrations equivalent to the dissolution of about 8 and 2% of respective concentrations in the composite. Time-distributions of hydrophobic metals, determined by solid phase extraction-methanol elution, were more complex. Net release of hydrophobic Cu was greater in the absence of light than under a sequence of light-dark cycles; however, hydrophobic Zn release was not detected under the former conditions but contributed up to 50% of total aqueous Zn when light was present. These observations are interpreted in terms of the relative thermodynamic and photolytic stabilities of biocidal pyrithione complexes. - Hydrophobic Cu and Zn leached from antifouling paint particles into sea water appear to be pyrithione complexes.

  7. Leaching of hydrophobic Cu and Zn from discarded marine antifouling paint residues: Evidence for transchelation of metal pyrithiones

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Luke [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2009-12-15

    Leaching of Cu and Zn from a composite of discarded antifouling paint residues ([Cu] = 288 mg g{sup -1}; [Zn] = 96 mg g{sup -1}) into natural sea water has been studied over a period of 75 h. Total Cu and Zn were released according to a pseudo first-order reaction, with rate constants on the order of 0.3 and 2.5 (mg L{sup -1}){sup -1} h{sup -1}, respectively, and final concentrations equivalent to the dissolution of about 8 and 2% of respective concentrations in the composite. Time-distributions of hydrophobic metals, determined by solid phase extraction-methanol elution, were more complex. Net release of hydrophobic Cu was greater in the absence of light than under a sequence of light-dark cycles; however, hydrophobic Zn release was not detected under the former conditions but contributed up to 50% of total aqueous Zn when light was present. These observations are interpreted in terms of the relative thermodynamic and photolytic stabilities of biocidal pyrithione complexes. - Hydrophobic Cu and Zn leached from antifouling paint particles into sea water appear to be pyrithione complexes.

  8. Dielectric properties of polycrystalline Cu-Zn ferrites at microwave frequencies

    International Nuclear Information System (INIS)

    Lamani, Ashok R.; Jayanna, H.S.; Parameswara, P.; Somashekar, R.; Ramachander,; Rao, Ramchandra; Prasanna, G.D.

    2011-01-01

    Highlights: → Cu 1-x Zn x Fe 2 O 4 at different concentration are suitable for high frequency applications. → Dielectric properties are related with W-H plot. → The anisotropy due to the crystallite size effect is significant in change of dielectric constant. - Abstract: The real dielectric constant ε' and complex dielectric constant ε'' of Cu 1-x Zn x Fe 2 O 4 have been measured at room temperature in the high frequency range 1 MHz to 1.8 GHz. At low frequencies the dielectric loss is found to be constant up to 1.4 GHz and there is a sudden rise at 1.5 GHz. A qualitative explanation is given for the composition, frequency dependence of the dielectric constant and dielectric loss of Cu 1-x Zn x Fe 2 O 4 . These are correlated with the W-H plot which gives the information about change in the average crystal size and strain of the samples. The micro-morphological features of the samples were obtained by Scanning Electron Microscopy (SEM). The micrograph shows that the increase of the Zn content in Cu ferrite increases the grain size.

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

    Science.gov (United States)

    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. Electron paramagnetic resonance in Cu-doped ZnO

    Science.gov (United States)

    Buchheit, R.; Acosta-Humánez, F.; Almanza, O.

    2016-04-01

    In this work, ZnO and Cu-doped ZnO nanoparticles (Zn1-xCuxO, x = 3%), with a calcination temperature of 500∘C were synthesized using the sol-gel method. The particles were analyzed using atomic absorption spectroscopy (AAS), X-ray diffraction (XRD) and electron paramagnetic resonance (EPR) at X-band, measurement in a temperature range from 90 K to room temperature. AAS confirmed a good correspondence between the experimental doping concentration and the theoretical value. XRD reveals the presence of ZnO phase in hexagonal wurtzite structure and a nanoparticle size for the samples synthesized. EPR spectroscopy shows the presence of point defects in both samples with g-values of g = 1.959 for shallow donors and g = 2.004 for ionized vacancies. It is important when these materials are required have been used as catalysts, as suggested that it is not necessary prepare them at higher temperature. A simulation of the Cu EPR signal using an anisotropic spin Hamiltonian was performed and showed good coincidence with the experimental spectra. It was shown that Cu2+ ions enter interstitial octahedral sites of orthorhombic symmetry in the wurtzite crystal structure. Temperature dependence of the EPR linewidth and signal intensity shows a paramagnetic behavior of the sample in the measurement range. A Néel temperature TN = 78 ± 19 K was determined.

  11. Zn vacancy-donor impurity complexes in ZnO

    Science.gov (United States)

    Frodason, Y. K.; Johansen, K. M.; Bjørheim, T. S.; Svensson, B. G.; Alkauskas, A.

    2018-03-01

    Results from hybrid density functional theory calculations on the thermodynamic stability and optical properties of the Zn vacancy (VZn) complexed with common donor impurities in ZnO are reported. Complexing VZn with donors successively removes its charge-state transition levels in the band gap, starting from the most negative one. Interestingly, the presence of a donor leads only to modest shifts in the positions of the VZn charge-state transition levels, the sign and magnitude of which can be interpreted from a polaron energetics model by taking hole-donor repulsion into account. By employing a one-dimensional configuration coordinate model, luminescence lineshapes and positions were calculated. Due to the aforementioned effects, the isolated VZn gradually changes from a mainly nonradiative defect with transitions in the infrared region in n -type material, to a radiative one with broad emission in the visible range when complexed with shallow donors.

  12. Comment on "Active sites for CO2 hydrogenation to methanol on Cu/ZnO catalysts"

    DEFF Research Database (Denmark)

    Nakamura, Junji; Fujitani, Tadahiro; Kuld, Sebastian

    2017-01-01

    Kattel et al (Reports, 24 March 2017, p. 1296) report that a zinc on copper (Zn/Cu) surface undergoes oxidation to zinc oxide/copper (ZnO/Cu) during carbon dioxide (CO2) hydrogenation to methanol and conclude that the Cu-ZnO interface is the active site for methanol synthesis. Similar experiments...... conducted two decades ago by Fujitani and Nakamura et al demonstrated that Zn is attached to formate rather than being fully oxidized....

  13. Fatigue crack behavior on a Cu-Zn-Al SMA

    Directory of Open Access Journals (Sweden)

    V. Di Cocco

    2014-10-01

    Full Text Available In recent years, mechanical property of many SMA has improved in order to introduce these alloys in specific field of industry. Main examples of these alloys are the NiTi, Cu-Zn-Al and Cu-Al-Ni which are used in many fields of engineering such as aerospace or mechanical systems. Cu-Zn-Al alloys are characterized by good shape memory properties due to a bcc disordered structure stable at high temperature called β-phase, which is able to change by means of a reversible transition to a B2 structure after appropriate cooling, and reversible transition from B2 secondary to DO3 order, under other types of cooling. In β-Cu-Zn-Al shape memory alloys, the martensitic transformation is not in equilibrium at room temperature. It is therefore often necessary to obtain the martensitic structure, using a thermal treatment at high temperature followed by quenching. The martensitic phases can be either thermally-induced spontaneous transformation, or stressinduced, or cooling, or stressing the β- phase. Direct quenching from high temperatures to the martensite phase is the most effective because of the non-diffusive character of the transformation. The martensite inherits the atomic order from the β-phase. Precipitation of many kinds of intermetallic phases is the main problem of treatment on cu-based shape memory alloy. For instance, a precipitation of α-phase occurs in many low aluminum copper based SMA alloy and presence of α-phase implies a strong degradation of shape recovery. However, Cu-Zn-Al SMA alloys characterized by aluminum contents less than 5% cover a good cold machining and cost is lower than traditional NiTi SMA alloys. In order to improve the SMA performance, it is always necessary to identify the microstructural changing in mechanical and thermal conditions, using X-Ray analyses. In this work a Cu-Zn-Al SMA alloy obtained in laboratory has been microstructurally and metallographically characterized by means of X-Ray diffraction and Light

  14. Electrodeposition and Characterization of Mn-Cu-Zn Alloys for Corrosion Protection Coating

    Science.gov (United States)

    Tsurtsumia, Gigla; Gogoli, David; Koiava, Nana; Kakhniashvili, Izolda; Jokhadze, Nunu; Lezhava, Tinatin; Nioradze, Nikoloz; Tatishvili, Dimitri

    2017-12-01

    Mn-Cu-Zn alloys were electrodeposited from sulphate bath, containing citrate or EDTA and their mixtures as complexing ligands. The influence of bath composition and deposition parameters on alloys composition, cathodic current efficiency and structural and electrochemical properties were studied. At a higher current density (≥ 37.5 A dm-2) a uniform surface deposit of Mn-Cu-Zn was obtained. Optimal pH of electrolyte (0.3 mol/dm3Mn2+ + 0.6 mol/dm3 (NH4)2SO4 +0.1 mol/dm3Zn2++0.005 mol/dm3 Cu2++ 0.05mol/dm3Na3Cit + 0.15mol/dm3 EDTA; t=300C; τ=20 min) for silvery, nonporous coating of Mn-Cu-Zn alloy was within 6.5-7.5; coating composition: 71-83% Mn, 6-7.8% Cu, 11.5-20% Zn, current efficiency up to 40%. XRD patterns revealed BCT (body centred tetragonal) γ-Mn solid phase solution (lattice constants a=2.68 Å c=3.59 Å). Corrosion measurements of deposited alloys were performed in aerated 3.5% NaCl solution. The corrosion current density (icorr) of the electrodeposited alloys on carbon steel was 10 times lower than corrosion rate of pure zinc and manganese coatings. Triple alloy coatings corrosion potential (Ecorr = -1140 mV vs. Ag/AgCl) preserved negative potential value longer (more than three months) compared to carbon steel substrate (Ecorr = -670 mV vs. Ag/AgCl). Tafel polarization curves taken on Mn-Cu-Zn alloy coating in aerated 3.5% NaCl solution did not show a typical passivation behaviour which can be explained by formation oflow solubility of adherent corrosion products on the alloy surface. Corrosion test of Mn-Cu-Zn electrocoating in chlorine environment shows that it is the best cathodic protective coating for a steel product.

  15. Ab-initio atomic level stress and role of d-orbitals in CuZr, CuZn and CuY

    Science.gov (United States)

    Ojha, Madhusudan; Nicholson, Don M.; Egami, Takeshi

    2015-03-01

    Atomic level stress offers a new tool to characterize materials within the local approximation to density functional theory (DFT). Ab-initio atomic level stresses in B2 structures of CuZr, CuZn and CuY are calculated and results are explained on the basis of d-orbital contributions to Density of States (DOS). The overlap of d-orbital DOS plays an important role in the relative magnitude of atomic level stresses in these structures. The trends in atomic level stresses that we observed in these simple B2 structures are also seen in complex structures such as liquids, glasses and solid solutions. The stresses are however modified by the different coordination and relaxed separation distances in these complex structures. We used the Locally Self-Consistent Multiple Scattering (LSMS) code and Vienna Ab-initio Simulation Package (VASP) for ab-initio calculations.

  16. Massive spalling of Cu-Zn and Cu-Al intermetallic compounds at the interface between solders and Cu substrate during liquid state reaction

    Science.gov (United States)

    Kotadia, H. R.; Panneerselvam, A.; Mokhtari, O.; Green, M. A.; Mannan, S. H.

    2012-04-01

    The interfacial intermetallic compound (IMC) formation between Cu substrate and Sn-3.8Ag-0.7Cu-X (wt.%) solder alloys has been studied, where X consists of 0-5% Zn or 0-2% Al. The study has focused on the effect of solder volume as well as the Zn or Al concentration. With low solder volume, when the Zn and Al concentrations in the solder are also low, the initial Cu-Zn and Al-Cu IMC layers, which form at the solder/substrate interface, are not stable and spall off, displaced by a Cu6Sn5 IMC layer. As the total Zn or Al content in the system increases by increasing solder volume, stable CuZn or Al2Cu IMCs form on the substrate and are not displaced. Increasing concentration of Zn has a similar effect of stabilizing the Cu-Zn IMC layer and also of forming a stable Cu5Zn8 layer, but increasing Al concentration alone does not prevent spalling of Al2Cu. These results are explained using a combination of thermodynamic- and kinetics-based arguments.

  17. Metal based pharmacologically active complexes of Cu(II), Ni(II) and Zn(II): synthesis, spectral, XRD, antimicrobial screening, DNA interaction and cleavage investigation.

    Science.gov (United States)

    Raman, Natarajan; Mahalakshmi, Rajkumar; Arun, T; Packianathan, S; Rajkumar, R

    2014-09-05

    The present contribution reports a thorough characterization of newly obtained metallointercalators incorporating Schiff bases, formed by the condensation of N-acetoacetyl-o-toluidine with 1-amino-4-nitrobenzene (L(1))/1-amino-4-chlorobenzene (L(2)) as main ligand and 1,10-phenanthroline as co-ligand respectively. The characterization of newly formed metallointercalators has been done by (1)H NMR, UV-Vis, IR, EPR spectroscopy and molar conductivity studies. X-ray powder diffraction illustrates that they are crystalline nature. Binding interaction of these complexes with calf thymus (CT-DNA) has been investigated by emission, absorption, viscosity, cyclic voltammetry and differential pulse voltammetry. DNA binding experiments results reveal that the synthesized complexes interact with DNA through intercalative mode. The in vitro antibacterial and antifungal assay indicate that these complexes are good antimicrobial agents against various pathogens. The DNA cleavage exhibits that they act as efficient cleaving agents. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Dynamic Behavior of CuZn Nanoparticles under Oxidizing and Reducing Conditions

    DEFF Research Database (Denmark)

    Holse, Christian; Elkjær, Christian Fink; Nierhoff, Anders Ulrik Fregerslev

    2015-01-01

    migrate to the Cu surface forming a Cu–Zn surface alloy. The oxidation and reduction dynamics of the CuZn nanoparticles is of great importance to industrial methanol synthesis for which the direct interaction of Cu and ZnO nanocrystals synergistically boosts the catalytic activity. Thus, the present......The oxidation and reduction of CuZn nanoparticles was studied using X-ray photoelectron spectroscopy (XPS) and in situ transmission electron microscopy (TEM). CuZn nanoparticles with a narrow size distribution were produced with a gas-aggregation cluster source in conjunction with mass......-filtration. A direct comparison between the spatially averaged XPS information and the local TEM observations was thus made possible. Upon oxidation in O2, the as-deposited metal clusters transform into a polycrystalline cluster consisting of separate CuO and ZnO nanocrystals. Specifically, the CuO is observed...

  19. Adsorption of Cu, As, Pb and Zn by Banana Trunk

    International Nuclear Information System (INIS)

    Nurzulaifa Shaheera Erne Mohd Yasim; Zitty Sarah Ismail; Suhanom Mohd Zaki; Mohd Fahmi Abd Azis

    2016-01-01

    The purpose of this study is to investigate the effectiveness of banana trunk as an adsorbent in removal of heavy metals in aqueous solution. Functional groups of adsorbent were determined using Fourier Transform Infrared spectroscopy (FTIR). Batch experiments were conducted to determine the adsorption percentage of heavy metals (Cu, As, Pb and Zn). The optimum adsorption using banana trunk was based on pH difference, contact time and dosage. Adsorption percentage was found to be proportional to pH, contact time and dosage. Maximum adsorption percentage of Cu, As, Pb and Zn at pH 6, 100 minutes and 8 gram of dosage are 95.80 %, 75.40 %, 99.36 % and 97.24 %, respectively. Langmuir and Freundlich isotherms were used to determine the equilibrium state for heavy metals ion adsorption experiments. All equilibrium heavy metals were well explained by the Freundlich isotherm model with R"2= 0.9441, R"2= 0.8671, R"2= 0.9489 and R"2= 0.9375 for Cu, As, Pb and Zn respectively. It is concluded that banana trunk has considerable potential for the removal of heavy metals from aqueous solution. (author)

  20. Tolerance of spermatogonia to oxidative stress is due to high levels of Zn and Cu/Zn superoxide dismutase.

    Directory of Open Access Journals (Sweden)

    Fritzie T Celino

    Full Text Available BACKGROUND: Spermatogonia are highly tolerant to reactive oxygen species (ROS attack while advanced-stage germ cells such as spermatozoa are much more susceptible, but the precise reason for this variation in ROS tolerance remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using the Japanese eel testicular culture system that enables a complete spermatogenesis in vitro, we report that advanced-stage germ cells undergo intense apoptosis and exhibit strong signal for 8-hydroxy-2'-deoxyguanosine, an oxidative DNA damage marker, upon exposure to hypoxanthine-generated ROS while spermatogonia remain unaltered. Activity assay of antioxidant enzyme, superoxide dismutase (SOD and Western blot analysis using an anti-Copper/Zinc (Cu/Zn SOD antibody showed a high SOD activity and Cu/Zn SOD protein concentration during early spermatogenesis. Immunohistochemistry showed a strong expression for Cu/Zn SOD in spermatogonia but weak expression in advanced-stage germ cells. Zn deficiency reduced activity of the recombinant eel Cu/Zn SOD protein. Cu/Zn SOD siRNA decreased Cu/Zn SOD expression in spermatogonia and led to increased oxidative damage. CONCLUSIONS/SIGNIFICANCE: These data indicate that the presence of high levels of Cu/Zn SOD and Zn render spermatogonia resistant to ROS, and consequently protected from oxidative stress. These findings provide the biochemical basis for the high tolerance of spermatogonia to oxidative stress.

  1. Electrospray ionization mass spectrometric investigations of the complexation behavior of macrocyclic thiacrown ethers with bivalent transitional metals (Cu, Co, Ni and Zn)

    Czech Academy of Sciences Publication Activity Database

    Tsybizova, Alexandra; Tarábek, Ján; Buchta, Michal; Holý, Petr; Schröder, Detlef

    2012-01-01

    Roč. 26, č. 19 (2012), s. 2287-2294 ISSN 0951-4198 R&D Projects: GA AV ČR IAA400550704 Grant - others:European Research Council(XE) AdG HORIZOMS Institutional support: RVO:61388963 Keywords : pendant crown thioethers * gas-phase * copper (II) complexes * stability constants * ESI-MS Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.509, year: 2012

  2. Room-temperature ferromagnetic properties of Cu-doped ZnO rod ...

    Indian Academy of Sciences (India)

    We have investigated properties of the Cu-doped ZnO crystalline film synthesized by the hydrothermal method. X-ray diffraction and X-ray ... DMSs are semiconducting alloys whose lattice is made up in part of substitutional magnetic ... investigate Cu-doped ZnO system (Hou et al 2007a, b), as. Cu is a potential magnetic ion ...

  3. Metallothionein Zn(2+)- and Cu(2+)-clusters from first-principles calculations

    DEFF Research Database (Denmark)

    Greisen, Per Junior; Jespersen, Jakob Berg; Kepp, Kasper Planeta

    2012-01-01

    Detailed electronic structures of Zn(ii) and Cu(ii) clusters from metallothioneins (MT) have been obtained using density functional theory (DFT), in order to investigate how oxidative stress-caused Cu(ii) intermediates affect Zn-binding to MT and cooperatively lead to Cu(i)MT. The inferred accura...

  4. CuO and ZnO nanoparticles: phytotoxicity, metal speciation, and induction of oxidative stress in sand-grown wheat

    Science.gov (United States)

    Dimkpa, Christian O.; McLean, Joan E.; Latta, Drew E.; Manangón, Eliana; Britt, David W.; Johnson, William P.; Boyanov, Maxim I.; Anderson, Anne J.

    2012-09-01

    Metal oxide nanoparticles (NPs) are reported to impact plant growth in hydroponic systems. This study describes the impact of commercial CuO (release did not account for the changes in plant growth. Bioaccumulation of Cu, mainly as CuO and Cu(I)-sulfur complexes, and Zn as Zn-phosphate was detected in the shoots of NP-challenged plants. Total Cu and Zn levels in shoot were similar whether NP or bulk materials were used. Oxidative stress in the NP-treated plants was evidenced by increased lipid peroxidation and oxidized glutathione in roots and decreased chlorophyll content in shoots; higher peroxidase and catalase activities were present in roots. These findings correlate with the NPs causing increased production of reactive oxygen species. The accumulation of Cu and Zn from NPs into edible plants has relevance to the food chain.

  5. Study On Nanohardness Of Phases Occurring In ZnAl22Cu3 And ZnAl40Cu3 Alloys

    Directory of Open Access Journals (Sweden)

    Michalik R.

    2015-06-01

    Full Text Available Zn-Al alloys are mainly used due to their high tribological and damping properties. A very important issue is determination of the hardness of the phases present in the Zn-Al-Cu alloys. Unfortunately, in literature there is lack of studies on the hardness of the phases present in the alloys Zn-Al-Cu. The aim of this research was to determine the hardness of the phases present in the ZnAl22Cu3Si and ZnAl40Cu3Si alloys. The scope of the research included examination of the structure, chemical composition of selected micro-regions and hardness of phases present in the examined alloys. The research carried out has shown, that CuZn4 phase is characterized by a similar hardness as the hardness of the interdendritic areas. The phases present in the structure of ZnAl40Cu3 and ZnAl22Cu3 alloys after soaking at the temperature of 185 °C are characterized by lower hardness than the phase present in the structure of the as-cast alloys.

  6. Complete transformation of ZnO and CuO nanoparticles in ...

    Science.gov (United States)

    Here, we present evidence on complete transformation of ZnO and CuO nanoparticles, which are among the most heavily studied metal oxide particles, during 24 h in vitro toxicological testing with human T-lymphocytes. Synchrotron radiation-based X-ray absorption near edge structure (XANES) spectroscopy results revealed that Zn speciation profiles of 30 nm and 80 nm ZnO nanoparticles, and ZnSO4- exposed cells were almost identical with the prevailing species being Zn-cysteine. This suggests that ZnO nanoparticles are rapidly transformed during a standard in vitro toxicological assay, and are sequestered intracellularly, analogously to soluble Zn. Complete transformation of ZnO in the test conditions was further supported by almost identical Zn spectra in medium to which ZnO nanoparticles or ZnSO4 was added. Likewise, Cu XANES spectra for CuO and CuSO4-exposed cells and cell culture media were similar. These results together with our observation on similar toxicological profiles of ZnO and soluble Zn, and CuO and soluble Cu, underline the importance of dissolution and subsequent transformation of ZnO and CuO nanoparticles during toxicological testing and provide evidence that the nano-specific effect of ZnO and CuO nanoparticulates is negligible in this system. We strongly suggest to account for this aspect when interpreting the toxicological results of ZnO and CuO nanoparticles. Although a number of studies have discussed the transformation of nanoparticles during

  7. White organic light-emitting diodes with Zn-complexes.

    Science.gov (United States)

    Kim, Dong-Eun; Shin, Hoon-Kyu; Kim, Nam-Kyu; Lee, Burm-Jong; Kwon, Young-Soo

    2014-02-01

    This paper reviews OLEDs fabricated using Zn-complexes. Zn(HPB)2, Zn(HPB)q, and Zn(phen)q were synthesized as new electroluminescence materials. The electron affinity (EA) and ionization potential (IP) of Zn complexes were also determined and devices were characterized. Zn complexes such as Zn(HPB)2, Zn(HPB)q, and Zn(phen)q were found to exhibit blue and yellow emissions with wavelengths of 455, 532, and 535 nm, respectively. On the other hand, Zn(HPB)2 and Zn(HPB)q were applied as hole-blocking materials. As a result, the OLED efficiency by using Zn(HPB)2 as a hole-blocking material was improved. In particular, the OLED property of Zn(HPB)2 was found to be better than that of Zn(HPB)q. Moreover, Zn(phen)q was used as an electron-transporting material and compared with Alq3. The performance of the device with Zn(phen)q as an electron-transporting material was improved compared with Alq3-based devices. The Zn complexes can possibly be used as hole-blocking and electron-transporting materials in OLED devices. A white emission was ultimately realized from the OLED devices using Zn-complexes as inter-layer components.

  8. The Cu2ZnSnSe4 thin films solar cells synthesized by electrodeposition route

    Science.gov (United States)

    Li, Ji; Ma, Tuteng; Wei, Ming; Liu, Weifeng; Jiang, Guoshun; Zhu, Changfei

    2012-06-01

    An electrodeposition route for preparing Cu2ZnSnSe4 thin films for thin film solar cell absorber layers is demonstrated. The Cu2ZnSnSe4 thin films are prepared by co-electrodeposition Cu-Zn-Sn metallic precursor and subsequently annealing in element selenium atmosphere. The structure, composition and optical properties of the films were investigated by X-ray diffraction (XRD), Raman spectrometry, energy dispersive spectrometry (EDS) and UV-VIS absorption spectroscopy. The Cu2ZnSnSe4 thin film with high crystalline quality was obtained, the band gap and absorption coefficient were 1.0 eV and 10-4 cm-1, which is quite suitable for solar cells fabrication. A solar cell with the structure of ZnO:Al/i-ZnO/CdS/Cu2ZnSnSe4/Mo/glass was fabricated and achieved an conversion efficiency of 1.7%.

  9. Preparation and characterization of water-soluble ZnSe:Cu/ZnS core/shell quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lei; Cao, Lixin, E-mail: caolixin@ouc.edu.cn; Su, Ge; Liu, Wei; Xia, Chenghui; Zhou, Huajian

    2013-09-01

    The synthesis and luminescent properties of water-soluble ZnSe:Cu/ZnS core/shell quantum dots (QDs) with different shell thickness are reported in this paper. X-ray powder diffraction (XRD) studies present that the ZnSe:Cu/ZnS core/shell QDs with different shell thickness have a cubic zinc-blende structure. The tests of transmission electron microscope (TEM) pictures exhibit that the QDs obtained are spherical-shaped particles and the average grain size increased from 2.7 to 3.8 nm with the growth of ZnS shell. The emission peak position of QDs has a small redshift from 461 to 475 nm with the growth of ZnS shell within the blue spectral window. The photoluminescence (PL) emission intensity and stability of the ZnSe:Cu core d-dots are both enhanced by coating ZnS shell on the surface of core d-dots. The largest PL intensity of the core/shell QDs is almost 3 times larger than that of Cu doped ZnSe quantum dots (ZnSe:Cu d-dots). The redshift of core/shell QDs compared with the core QDs are observed in both the absorption and the photoluminescence excitation spectra.

  10. Quantitative trait loci controlling Cu, Ca, Zn, Mn and Fe content in ...

    Indian Academy of Sciences (India)

    of essential minerals (such as Fe, Zn etc), breeding mineral- efficient crops that produce .... and seven digenic interactions were identified for Cu, Ca,. Zn, Mn and Fe, .... Eva P. 1993 Cadmium, copper and lead in wild rice from central. Canada.

  11. Thermomechanical Treatments on High Strength Al-Zn-Mg(-Cu) Alloys

    National Research Council Canada - National Science Library

    Di Russo, E; Conserva, M; Gatto, F

    1974-01-01

    An investigation was carried out to determine the metallurgical properties of Al-Zn-Mg and Al-Zn-Mg-Cu alloy products processed according to newly developed Final Thermomechanical Treatments (FTMT) of T-AHA type...

  12. Activation of a Cu/ZnO catalyst for methanol synthesis

    DEFF Research Database (Denmark)

    Andreasen, Jens Wenzel; Rasmussen, F.B.; Helveg, S.

    2006-01-01

    The structural changes during activation by temperature-programmed reduction of a Cu/ZnO catalyst for methanol synthesis have been studied by several in situ techniques. The catalyst is prepared by coprecipitation and contains 4.76 wt% Cu, which forms a substitutional solid solution with Zn......O as determined by resonant X-ray diffraction. In situ resonant X-ray diffraction reveals that the Cu atoms are extracted from the solid solution by the reduction procedure, forming metallic Cu crystallites. Cu is redispersed in bulk or surface Zn lattice sites upon oxidation by heating in air. The results...... is highly dispersed and in intimate contact with the surface of the host ZnO particles. The possibility of re-forming the (Zn,Cu)O solid solution by oxidation may provide a means of redispersing Cu in a deactivated catalyst....

  13. Preparation of carrier-free 67Cu by the 68Zn(γ,p) reaction

    International Nuclear Information System (INIS)

    Yagi, M.; Kondo, K.

    1978-01-01

    The preparation of pure, carrier-free 67 Cu using the 68 Zn(γ, p) reaction with an isotopically enriched 68 Zn(98.97%) target is described. The production rates of 67 Cu and contaminants were determined as a function of the maximum bremsstrahlung energies between 30 and 60 MeV. The chemical separation of the carrier-free 67 Cu and the recovery of the 68 Zn target were also studied. (author)

  14. Low Temperature Mechanical Properties of Scandium-Modified Al-Zn-Mg-Cu Alloys

    National Research Council Canada - National Science Library

    Senkov, O

    2002-01-01

    Tensile properties of three wrought alloys, (1) Al-10Zn-3Mg-1.2Cu-0.15Zr, (2) Al-10Zn-3Mg-1.2Cu-0.15Zr-0.39Mn-0.49Sc, and (3) Al-12Zn-3Mg-1.2Cu-0.15Zr-0.39Mn-0.49Sc were studied in T6 and T7 conditions at 298K and 77K...

  15. Formation of ferric flocks for the removal of Zn and Cu from dockyard wastewater

    DEFF Research Database (Denmark)

    Ottosen, Lisbeth M.; Arevalo, Edurado; Stichnothe, Heinz

    2006-01-01

    Wastewater from wash down of boat hulls contains typically Cu, Zn and organometallic biocides, e.g. tributyltin (TBT). In some cases this wastewater is led directly into the marine system. In the present paper a cheap flocculation method (iron flocculants) for removal of Cu and Zn from the wastew......Wastewater from wash down of boat hulls contains typically Cu, Zn and organometallic biocides, e.g. tributyltin (TBT). In some cases this wastewater is led directly into the marine system. In the present paper a cheap flocculation method (iron flocculants) for removal of Cu and Zn from...

  16. Compositional ratio effect on the surface characteristics of CuZn thin films

    Science.gov (United States)

    Choi, Ahrom; Park, Juyun; Kang, Yujin; Lee, Seokhee; Kang, Yong-Cheol

    2018-05-01

    CuZn thin films were fabricated by RF co-sputtering method on p-type Si(100) wafer with various RF powers applied on metallic Cu and Zn targets. This paper aimed to determine the morphological, chemical, and electrical properties of the deposited CuZn thin films by utilizing a surface profiler, atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), UV photoelectron spectroscopy (UPS), and a 4-point probe. The thickness of the thin films was fixed at 200 ± 8 nm and the roughness of the thin films containing Cu was smaller than pure Zn thin films. XRD studies confirmed that the preferred phase changed, and this tendency is dependent on the ratio of Cu to Zn. AES spectra indicate that the obtained thin films consisted of Cu and Zn. The high resolution XPS spectra indicate that as the content of Cu increased, the intensities of Zn2+ decreased. The work function of CuZn thin films increased from 4.87 to 5.36 eV. The conductivity of CuZn alloy thin films was higher than pure metallic thin films.

  17. Enhanced wetting of Cu on ZnO by migration of subsurface oxygen vacancies

    DEFF Research Database (Denmark)

    Beinik, Igor; Helström, Matti; Jensen, Thomas Nørregaard

    2015-01-01

    is of utmost importance. The Cu/ZnO system is among the most investigated of such systems in model studies, but the presence of subsurface ZnO defects and their important role for adhesion on ZnO have been unappreciated so far. Here we reveal that the surface-directed migration of subsurface defects affects...... the Cu adhesion on polar ZnO(0001) in the technologically interesting temperature range up to 550 K. This leads to enhanced adhesion and ultimately complete wetting of ZnO(0001) by a Cu overlayer. On the basis of our experimental and computational results we demonstrate a mechanism which implies...

  18. CuO and ZnO nanoparticles: phytotoxicity, metal speciation, and induction of oxidative stress in sand-grown wheat

    Energy Technology Data Exchange (ETDEWEB)

    Dimkpa, Christian O., E-mail: cdimkpa@usu.edu [Utah State University, Department of Biological Engineering (United States); McLean, Joan E. [Utah State University, Utah Water Research Laboratory (United States); Latta, Drew E. [Argonne National Laboratory, Biosciences Division (United States); Manangon, Eliana [University of Utah, Department of Geology and Geophysics (United States); Britt, David W. [Utah State University, Department of Biological Engineering (United States); Johnson, William P. [University of Utah, Department of Geology and Geophysics (United States); Boyanov, Maxim I. [Argonne National Laboratory, Biosciences Division (United States); Anderson, Anne J. [Utah State University, Department of Biological Engineering (United States)

    2012-09-15

    Metal oxide nanoparticles (NPs) are reported to impact plant growth in hydroponic systems. This study describes the impact of commercial CuO (<50 nm) and ZnO (<100 nm) NPs on wheat (Triticum aestivum) grown in a solid matrix, sand. The NPs contained both metallic and non-metallic impurities to different extents. Dynamic light scattering and atomic force microscopy (AFM) assessments confirmed aggregation of the NPs to submicron sizes. AFM showed transformation of ZnO NPs from initial rhomboid shapes in water to elongated rods in the aqueous phase of the sand matrix. Solubilization of metals occurred in the sand at similar rates from CuO or ZnO NPs as their bulk equivalents. Amendment of the sand with 500 mg Cu and Zn/kg sand from the NPs significantly (p = 0.05) reduced root growth, but only CuO NPs impaired shoot growth; growth reductions were less with the bulk amendments. Dissolved Cu from CuO NPs contributed to their phytotoxicity but Zn release did not account for the changes in plant growth. Bioaccumulation of Cu, mainly as CuO and Cu(I)-sulfur complexes, and Zn as Zn-phosphate was detected in the shoots of NP-challenged plants. Total Cu and Zn levels in shoot were similar whether NP or bulk materials were used. Oxidative stress in the NP-treated plants was evidenced by increased lipid peroxidation and oxidized glutathione in roots and decreased chlorophyll content in shoots; higher peroxidase and catalase activities were present in roots. These findings correlate with the NPs causing increased production of reactive oxygen species. The accumulation of Cu and Zn from NPs into edible plants has relevance to the food chain.

  19. Study of Cu-Al-Zn alloys hardness temperature dependence

    International Nuclear Information System (INIS)

    Kurmanova, D.T.; Skakov, M.K.; Melikhov, V.D.

    2001-01-01

    In the paper the results of studies for the Cu-Al-Zn ternary alloys hardness temperature dependence are presented. The method of 'hot hardness' has been used during study of the solid state phase transformations and under determination of the hot stability boundaries. Due to the samples brittleness a hardness temperature dependence definition is possible only from 350-400 deg. C. Sensitivity of the 'hot hardness' method is decreasing within high plasticity range, so the measurements have been carried out only up to 700-800 deg. C. It is shown, that the alloys hardness dependence character from temperature is close to exponential one within the certain structure modification existence domain

  20. ZnCuInS/ZnSe/ZnS Quantum Dot-Based Downconversion Light-Emitting Diodes and Their Thermal Effect

    Directory of Open Access Journals (Sweden)

    Wenyan Liu

    2015-01-01

    Full Text Available The quantum dot-based light-emitting diodes (QD-LEDs were fabricated using blue GaN chips and red-, yellow-, and green-emitting ZnCuInS/ZnSe/ZnS QDs. The power efficiencies were measured as 14.0 lm/W for red, 47.1 lm/W for yellow, and 62.4 lm/W for green LEDs at 2.6 V. The temperature effect of ZnCuInS/ZnSe/ZnS QDs on these LEDs was investigated using CIE chromaticity coordinates, spectral wavelength, full width at half maximum (FWHM, and power efficiency (PE. The thermal quenching induced by the increased surface temperature of the device was confirmed to be one of the important factors to decrease power efficiencies while the CIE chromaticity coordinates changed little due to the low emission temperature coefficients of 0.022, 0.050, and 0.068 nm/°C for red-, yellow-, and green-emitting ZnCuInS/ZnSe/ZnS QDs. These indicate that ZnCuInS/ZnSe/ZnS QDs are more suitable for downconversion LEDs compared to CdSe QDs.

  1. Microstructure and magnetic studies of Mg-Ni-Zn-Cu ferrites

    International Nuclear Information System (INIS)

    Bachhav, S.G.; Patil, R.S.; Ahirrao, P.B.; Patil, A.M.; Patil, D.R.

    2011-01-01

    Highlights: → Ni x Mg 0.5-x Cu 0.1 Zn 0.4 Fe 2 O 4 ferrite shows spinel structure. → Lattice parameter, X-ray density, porosity increase with increase in Ni content. → The IR spectra show tetrahedral and octahedral complexes. → Initial permeability remains constant with temperature and drops to zero at certain temperature which is in close agreement with Curie temperature. → The Curie temperature shows increasing trend with Ni content. - Abstract: Soft Mg-Ni-Zn-Cu spinel ferrites having general chemical formula Ni x Mg 0.5-x Cu 0.1 Zn 0.4 Fe 2 O 4 (where x 0.1, 0.2, 0.3, 0.4 and 0.5) were prepared by standard double sintering ceramic method. The samples were characterized by X-ray diffraction at room temperature. The X-ray diffraction (XRD) study revealed that lattice parameter decreases with increase in Ni content, resulting in a reduction in lattice strain. The electrical and magnetic properties of the synthesized ferrites have been investigated as a function of temperature. The variation of initial permeability and AC susceptibility with temperature exhibits normal ferrimagnetic behavior. The variation of initial permeability with frequency is studied. The Curie temperature (T C ) in the present work was determined from initial permeability and AC susceptibility. The Curie temperature increases with Ni content.

  2. Synthesis and characterisation of Cu(II), Ni(II), Mn(II), Zn(II) and VO(II ...

    Indian Academy of Sciences (India)

    Unknown

    Synthesis and characterisation of Cu(II), Ni(II), Mn(II), Zn(II) and VO(II) Schiff base complexes derived from o-phenylenediamine and acetoacetanilide. N RAMAN*, Y PITCHAIKANI RAJA and A KULANDAISAMY. Department of Chemistry, VHNSN College, Virudhunagar 626 001, India e-mail: ra_man@123india.com.

  3. Mixed ligand complexes of Cu(II)/Zn(II) ions containing (m-)/(p-) carboxylato phenyl azo pentane 2,4-dione and 2,2‧-bipyridine/1,10 phenanthroline: Synthesis, characterization, DNA binding, nuclease and topoisomerase I inhibitory activity

    Science.gov (United States)

    Hasan, Md. Amin; Kumari, Niraj; Singh, Kanhaiya; Singh, Kiran; Mishra, Lallan

    2016-01-01

    Metal complexes of type [Cu(L1H)2(bpy)] (1), [Zn(L1H)2(bpy)] (2), [Cu(L2H)2(bpy)] (3) and [Cu(L2H)2(Phen)] (4) (L1H2 = 3-[N‧-(1-acetyl-2-oxo-propylidene)-hydrazino]-benzoic acid, L2H2 = 4-[N‧-(1-acetyl-2-oxo-propylidene)-hydrazino]-benzoic acid, bpy = 2,2‧-bipyridine, Phen = 1,10 phenanthroline) are synthesized and characterized using spectroscopic techniques (FT-IR, 1H NMR, 13C NMR, electronic absorption and emission) and elemental analysis data. The assembly of the complexes involving intramolecular H-bonding is displayed using corresponding crystal structure. Binding of the complexes separately with Calf Thymus DNA is monitored using UV-vis spectral titrations. The displacement of ethidium bromide (EB) bound to DNA by the complexes, in phosphate buffer solution (pH ∼ 7.2) is monitored using fluorescence spectral titrations. Nuclease activity of the complexes follow the order 4 > 3 > 1 > 2. The gel electrophoretic mobility assay measurement in presence of minor groove binder 4‧,6-diamidino-2-phenylindole (DAPI), suggests that complexes preferably bind with the minor groove of DNA. Topoisomerase I inhibitory activity of the complexes 3 and 4 inhibit topoisomerase I activity with IC50 values of 112 and 87 μM respectively.

  4. Mixed ligand complexes of Cu(II)/Zn(II) ions containing (m-)/(p-) carboxylato phenyl azo pentane 2,4-dione and 2,2'-bipyridine/1,10 phenanthroline: Synthesis, characterization, DNA binding, nuclease and topoisomerase I inhibitory activity.

    Science.gov (United States)

    Hasan, Md Amin; Kumari, Niraj; Singh, Kanhaiya; Singh, Kiran; Mishra, Lallan

    2016-01-05

    Metal complexes of type [Cu(L1H)2(bpy)] (1), [Zn(L1H)2(bpy)] (2), [Cu(L2H)2(bpy)] (3) and [Cu(L2H)2(Phen)] (4) (L1H2=3-[N'-(1-acetyl-2-oxo-propylidene)-hydrazino]-benzoic acid, L2H2=4-[N'-(1-acetyl-2-oxo-propylidene)-hydrazino]-benzoic acid, bpy=2,2'-bipyridine, Phen=1,10 phenanthroline) are synthesized and characterized using spectroscopic techniques (FT-IR, (1)H NMR, (13)C NMR, electronic absorption and emission) and elemental analysis data. The assembly of the complexes involving intramolecular H-bonding is displayed using corresponding crystal structure. Binding of the complexes separately with Calf Thymus DNA is monitored using UV-vis spectral titrations. The displacement of ethidium bromide (EB) bound to DNA by the complexes, in phosphate buffer solution (pH∼7.2) is monitored using fluorescence spectral titrations. Nuclease activity of the complexes follow the order 4>3>1>2. The gel electrophoretic mobility assay measurement in presence of minor groove binder 4',6-diamidino-2-phenylindole (DAPI), suggests that complexes preferably bind with the minor groove of DNA. Topoisomerase I inhibitory activity of the complexes 3 and 4 inhibit topoisomerase I activity with IC50 values of 112 and 87μM respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Interplay of Cu and oxygen vacancy in optical transitions and screening of excitons in ZnO:Cu films

    International Nuclear Information System (INIS)

    Darma, Yudi; Rusydi, Andrivo; Seng Herng, Tun; Marlina, Resti; Fauziah, Resti; Ding, Jun

    2014-01-01

    We study room temperature optics and electronic structures of ZnO:Cu films as a function of Cu concentration using a combination of spectroscopic ellipsometry, photoluminescence, and ultraviolet-visible absorption spectroscopy. Mid-gap optical states, interband transitions, and excitons are observed and distinguishable. We argue that the mid-gap states are originated from interactions of Cu and oxygen vacancy (Vo). They are located below conduction band (Zn4s) and above valence band (O2p) promoting strong green emission and narrowing optical band gap. Excitonic states are screened and its intensities decrease upon Cu doping. Our results show the importance of Cu and Vo driving the electronic structures and optical transitions in ZnO:Cu films

  6. Interplay of Cu and oxygen vacancy in optical transitions and screening of excitons in ZnO:Cu films

    Science.gov (United States)

    Darma, Yudi; Seng Herng, Tun; Marlina, Resti; Fauziah, Resti; Ding, Jun; Rusydi, Andrivo

    2014-02-01

    We study room temperature optics and electronic structures of ZnO:Cu films as a function of Cu concentration using a combination of spectroscopic ellipsometry, photoluminescence, and ultraviolet-visible absorption spectroscopy. Mid-gap optical states, interband transitions, and excitons are observed and distinguishable. We argue that the mid-gap states are originated from interactions of Cu and oxygen vacancy (Vo). They are located below conduction band (Zn4s) and above valence band (O2p) promoting strong green emission and narrowing optical band gap. Excitonic states are screened and its intensities decrease upon Cu doping. Our results show the importance of Cu and Vo driving the electronic structures and optical transitions in ZnO:Cu films.

  7. Synthesis of Cu and Ce co-doped ZnO nanoparticles: crystallographic, optical, molecular, morphological and magnetic studies

    Directory of Open Access Journals (Sweden)

    Rawat Mohit

    2017-07-01

    Full Text Available In the present research work, crystallographic, optical, molecular, morphological and magnetic properties of Zn1-xCuxO (ZnCu and Zn1-x-yCeyCuxO (ZnCeCu nanoparticles have been investigated. Polyvinyl alcohol (PVA coated ZnCu and ZnCeCu nanoparticles have been synthesized by chemical sol-gel method and thoroughly studied using various characterization techniques. X-ray diffraction pattern indicates the wurtzite structure of the synthesized ZnCu and ZnCeCu particles. Transmission electron microscopy analysis shows that the synthesized ZnCu and ZnCeCu particles are of spherical shape, having average sizes of 27 nm and 23 nm, respectively. The incorporation of Cu and Ce in the ZnO lattice has been confirmed through Fourier transform infrared spectroscopy. Room temperature photoluminescence spectra of the ZnO doped with Cu and co-doped Ce display two emission bands, predominant ultra-violet near-band edge emission at 409.9 nm (3 eV and a weak green-yellow emission at 432.65 nm (2.27 eV. Room temperature magnetic study confirms the diamagnetic behavior of ZnCu and ferromagnetic behavior of ZnCeCu.

  8. Synthesis of highly non-stoichiometric Cu{sub 2}ZnSnS{sub 4} nanoparticles with tunable bandgaps

    Energy Technology Data Exchange (ETDEWEB)

    Hamanaka, Yasushi, E-mail: hamanaka@nitech.ac.jp; Oyaizu, Wataru; Kawase, Masanari [Nagoya Institute of Technology, Department of Materials Science and Engineering (Japan); Kuzuya, Toshihiro [Muroran Institute of Technology, College of Design and Manufacturing Technology (Japan)

    2017-01-15

    Non-stoichiometric Cu{sub 2}ZnSnS{sub 4} nanoparticles with average diameters of 4–15 nm and quasi-polyhedral shape were successfully synthesized by a colloidal method. We found that a non-stoichiometric composition of Zn to Cu in Cu{sub 2}ZnSnS{sub 4} nanoparticles yielded a correlation where Zn content increased with a decrease in Cu content, suggesting formation of lattice defects relating to Cu and Zn, such as a Cu vacancy (V{sub Cu}), antisite with Zn replacing Cu (Zn{sub Cu}), and/or defect cluster of V{sub Cu} and Zn{sub Cu}. The bandgap energy of Cu{sub 2}ZnSnS{sub 4} nanoparticles systematically varies between 1.56 and 1.83 eV depending on the composition ratios of Cu and Zn, resulting in a wider bandgap for Cu-deficient Cu{sub 2}ZnSnS{sub 4} nanoparticles. These characteristics can be ascribed to the modification in electronic band structures due to formation of V{sub Cu} and Zn{sub Cu} on the analogy of ternary copper chalcogenide, chalcopyrite CuInSe{sub 2}, in which the top of the valence band shifts downward with decreasing Cu contents, because much like the structure of CuInSe{sub 2}, the top of the valence band is composed of a Cu 3d orbital in Cu{sub 2}ZnSnS{sub 4}.

  9. Genotoxicity and cytotoxicity response to environmentally relevant complex metal mixture (Zn, Cu, Ni, Cr, Pb, Cd) accumulated in Atlantic salmon (Salmo salar). Part I: importance of exposure time and tissue dependence.

    Science.gov (United States)

    Stankevičiūtė, Milda; Sauliutė, Gintarė; Svecevičius, Gintaras; Kazlauskienė, Nijolė; Baršienė, Janina

    2017-10-01

    Health impact of metal mixture at environment realistic concentrations are difficult to predict especially for long-term effects where cause-and-effect relationships may not be directly obvious. This study was aimed to evaluate metal mixture (Zn-0.1, Cu-0.01, Ni-0.01, Cr-0.01, Pb-0.005 and Cd-0.005 mg/L, respectively for 1, 2, 4, 7, 14 and 28 days at concentrations accepted for the inland waters in EU) genotoxicity (micronuclei, nuclear buds, nuclear buds on filament), cytotoxicity (8-shaped nuclei, fragmented-apoptotic erythrocytes), bioaccumulation, steady-state and the reference level of geno-cytotoxicity in hatchery-reared Atlantic salmon tissues. Metals accumulated mostly in gills and kidneys, to the lesser extent in the muscle. Uptake of metals from an entire mixture in the fish for 14 days is sufficient to reach steady-state Cr, Pb concentrations in all tissues; Zn, Cu-in kidneys and muscle, Ni-in liver, kidneys, muscle and Cd-in muscle. Treatment with metal mixture significantly increased summed genotoxicity levels at 7 days of exposure in peripheral blood and liver erythrocytes, at 14 days of exposure in gills and kidney erythrocytes. Significant elevation of cytotoxicity was detected after 2 and 14 days of exposure in gills erythrocytes and after 28 days-in peripheral blood erythrocytes. The amount of Cu, Cr, Pb and Cd accumulated in tissues was dependent upon duration of exposure; nuclear buds, 8-shaped nuclei frequencies also were dependent upon duration of exposure. This study indicates that metals at low levels when existing in mixture causes significant geno-cytotoxicity responses and metals bioaccumulation in salmon.

  10. Transverse excitations in liquid Fe, Cu and Zn

    International Nuclear Information System (INIS)

    Hosokawa, S; Inui, M; Kajihara, Y; Tsutsui, S; Baron, A Q R

    2015-01-01

    Transverse acoustic (TA) excitation modes were observed in inelastic x-ray scattering spectra of liquid Fe, Cu and Zn. From the analysis of current correlation functions, we concluded that TA excitation modes can experimentally be detected through the quasi-TA branches in the longitudinal current correlation spectra in these liquid metals. The microscopic elastic constants are estimated and a characteristic difference from macroscopic polycrystalline value was found in Poisson's ratio of liquid Fe, which shows an extremely softer value of ∼0.38 compared with the macroscopic value of ∼0.275. The lifetime of the TA modes were determined to be ∼0.45 ps for liquid Fe and Cu and ∼0.55 ps for liquid Zn, reflecting different interatomic correlations between liquid transition metals and non-transition metals. The propagation length of the TA modes are ∼0.85 nm in all of liquid metals, corresponding to the size of icosahedral or similar size of cages formed instantaneously in these liquid metals. (paper)

  11. Cu2+ in layered compounds: origin of the compressed geometry in the model system K2ZnF4:Cu2+.

    Science.gov (United States)

    Aramburu, J A; García-Lastra, J M; García-Fernández, P; Barriuso, M T; Moreno, M

    2013-06-17

    Many relevant properties (including superconductivity and colossal magnetoresistance) of layered materials containing Cu(2+), Ag(2+), or Mn(3+) ions are commonly related to the Jahn-Teller instability. Along this line, the properties of the CuF6(4-) complex in the K2ZnF4 layered perovskite have recently been analyzed using a parametrized Jahn-Teller model with an imposed strain [Reinen, D. Inorg. Chem.2012, 51, 4458]. Here, we present results of ab initio periodic supercell and cluster calculations on K2ZnF4:Cu(2+), showing unequivocally that the actual origin of the unusual compressed geometry of the CuF6(4-) complex along the crystal c axis in that tetragonal lattice is due to the presence of an electric field due to the crystal surrounding the impurity. Our calculations closely reproduce the experimental optical spectrum. The calculated values of the equilibrium equatorial and axial Cu(2+)-F(-) distances are, respectively, R(ax) = 193 pm and R(eq) = 204 pm, and so the calculated distortion R(ax) - R(eq) = 11 pm is three times smaller than the estimated through the parametrized Jahn-Teller model. As a salient feature, we find that if the CuF6(4-) complex would assume a perfect octahedral geometry (R(ax) = R(eq) = 203 pm) the antibonding a(1g)*(∼3z(2) - r(2)) orbital is placed above b(1g)*(∼x(2) - y(2)) with a transition energy E((2)A(1g) → (2)B(1g)) = 0.34 eV. This surprising fact stresses that about half the experimental value E((2)A(1g) → (2)B(1g)) = 0.70 eV is not due to the small shortening of the axial Cu(2+)-F(-) distance, but it comes from the electric field, E(R)(r), created by the rest of the lattice ions on the CuF6(4-) complex. This internal field, displaying tetragonal symmetry, is thus responsible for the compressed geometry in K2ZnF4:Cu(2+) and the lack of symmetry breaking behind the ligand relaxation. Moreover, we show that the electronic energy gain in this process comes from bonding orbitals and not from antibonding ones. The present

  12. Optimization of Cu-Zn Massive Sulphide Flotation by Selective Reagents

    Science.gov (United States)

    Soltani, F.; Koleini, S. M. J.; Abdollahy, M.

    2014-10-01

    Selective floatation of base metal sulphide minerals can be achieved by using selective reagents. Sequential floatation of chalcopyrite-sphalerite from Taknar (Iran) massive sulphide ore with 3.5 % Zn and 1.26 % Cu was studied. D-optimal design of response surface methodology was used. Four mixed collector types (Aer238 + SIPX, Aero3477 + SIPX, TC1000 + SIPX and X231 + SIPX), two depressant systems (CuCN-ZnSO4 and dextrin-ZnSO4), pH and ZnSO4 dosage were considered as operational factors in the first stage of flotation. Different conditions of pH, CuSO4 dosage and SIPX dosage were studied for sphalerite flotation from first stage tailings. Aero238 + SIPX induced better selectivity for chalcopyrite against pyrite and sphalerite. Dextrin-ZnSO4 was as effective as CuCN-ZnSO4 in sphalerite-pyrite depression. Under optimum conditions, Cu recovery, Zn recovery and pyrite content in Cu concentrate were 88.99, 33.49 and 1.34 % by using Aero238 + SIPX as mixed collector, CuCN-ZnSO4 as depressant system, at ZnSO4 dosage of 200 g/t and pH 10.54. When CuCN was used at the first stage, CuSO4 consumption increased and Zn recovery decreased during the second stage. Maximum Zn recovery was 72.19 % by using 343.66 g/t of CuSO4, 22.22 g/t of SIPX and pH 9.99 at the second stage.

  13. Preparation of ZnO/Cu2O compound photocatalyst and application in treating organic dyes

    International Nuclear Information System (INIS)

    Xu Chao; Cao Lixin; Su Ge; Liu Wei; Liu Hui; Yu Yaqin; Qu Xiaofei

    2010-01-01

    ZnO/Cu 2 O compound photocatalysts were prepared by 'soak-deoxidize-air oxidation' with different concentrations of Cu 2+ (0.125, 0.25, 0.5, 1, 1.5 and 2 mol/L). The prepared ZnO/Cu 2 O samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), UV-vis diffuse reflectance spectrometer, and photochemical reaction instrument. The results show that ZnO was hexagonal wurtzite structure and the crystallinity had no change with the increase of Cu 2+ concentration. Cu 2 O belonged to cubic structure and the crystallinity increased with the increase of Cu 2+ concentration. ZnO were rods and bulks which had diameter of about 300-400 nm, some small round Cu 2 O particles which had a diameter of about 50 nm adhered to these rods and bulks. In the compounds the mole ratio of Cu 2 O to ZnO was 0.017, 0.025, 0.076, 0.137, 0.138, and 0.136, respectively. An absorbance in the visible light region between 400 and 610 nm was seen and the reflection rate became less with the mole ratio of Cu 2 O to ZnO increasing. The photocatalytic activities of ZnO/Cu 2 O compound were evaluated using a basic organic dye, methyl orange (MO). It was found that, compared with pure ZnO, the photocatalytic properties of ZnO/Cu 2 O compound were improved greatly and some compounds were better than pure Cu 2 O.

  14. Long-Lived Termite Queens Exhibit High Cu/Zn-Superoxide Dismutase Activity

    Directory of Open Access Journals (Sweden)

    Eisuke Tasaki

    2018-01-01

    Full Text Available In most organisms, superoxide dismutases (SODs are among the most effective antioxidant enzymes that regulate the reactive oxygen species (ROS generated by oxidative energy metabolism. ROS are considered main proximate causes of aging. However, it remains unclear if SOD activities are associated with organismal longevity. The queens of eusocial insects, such as termites, ants, and honeybees, exhibit extraordinary longevity in comparison with the nonreproductive castes, such as workers. Therefore, the queens are promising candidates to study the underlying mechanisms of aging. Here, we found that queens have higher Cu/Zn-SOD activity than nonreproductive individuals of the termite Reticulitermes speratus. We identified three Cu/Zn-SOD sequences and one Mn-SOD sequence by RNA sequencing in R. speratus. Although the queens showed higher Cu/Zn-SOD activity than the nonreproductive individuals, there were no differences in their expression levels of the Cu/Zn-SOD genes RsSOD1 and RsSOD3A. Copper (Cu2+ and Cu+ is an essential cofactor for Cu/Zn-SOD enzyme activity, and the queens had higher concentrations of copper than the workers. These results suggest that the high Cu/Zn-SOD activity of termite queens is related to their high levels of the cofactor rather than gene expression. This study highlights that Cu/Zn-SOD activity contributes to extraordinary longevity in termites.

  15. Structural and elemental characterization of high efficiency Cu2ZnSnS4 solar cells

    Science.gov (United States)

    Wang, Kejia; Shin, Byungha; Reuter, Kathleen B.; Todorov, Teodor; Mitzi, David B.; Guha, Supratik

    2011-01-01

    We have carried out detailed microstructural studies of phase separation and grain boundary composition in Cu2ZnSnS4 based solar cells. The absorber layer was fabricated by thermal evaporation followed by post high temperature annealing on hot plate. We show that inter-reactions between the bottom molybdenum and the Cu2ZnSnS4, besides triggering the formation of interfacial MoSx, results in the out-diffusion of Cu from the Cu2ZnSnS4 layer. Phase separation of Cu2ZnSnS4 into ZnS and a Cu-Sn-S compound is observed at the molybdenum-Cu2ZnSnS4 interface, perhaps as a result of the compositional out-diffusion. Additionally, grain boundaries within the thermally evaporated absorber layer are found to be either Cu-rich or at the expected bulk composition. Such interfacial compound formation and grain boundary chemistry likely contributes to the lower than expected open circuit voltages observed for the Cu2ZnSnS4 devices.

  16. Molecular distortion and charge transfer effects in ZnPc/Cu(111)

    KAUST Repository

    Amin, B.; Nazir, S.; Schwingenschlö gl, Udo

    2013-01-01

    The adsorption geometry and electronic properties of a zinc-phthalocyanine molecule on a Cu(111) substrate are studied by density functional theory. In agreement with experiment, we find remarkable distortions of the molecule, mainly as the central Zn atom tends towards the substrate to minimize the Zn-Cu distance. As a consequence, the Zn-N chemical bonding and energy levels of the molecule are significantly modified. However, charge transfer induces metallic states on the molecule and therefore is more important for the ZnPc/Cu(111) system than the structural distortions.

  17. Molecular distortion and charge transfer effects in ZnPc/Cu(111)

    KAUST Repository

    Amin, B.

    2013-04-23

    The adsorption geometry and electronic properties of a zinc-phthalocyanine molecule on a Cu(111) substrate are studied by density functional theory. In agreement with experiment, we find remarkable distortions of the molecule, mainly as the central Zn atom tends towards the substrate to minimize the Zn-Cu distance. As a consequence, the Zn-N chemical bonding and energy levels of the molecule are significantly modified. However, charge transfer induces metallic states on the molecule and therefore is more important for the ZnPc/Cu(111) system than the structural distortions.

  18. Dielectric relaxation behavior and impedance studies of Cu2+ ion doped Mg - Zn spinel nanoferrites

    Science.gov (United States)

    Choudhary, Pankaj; Varshney, Dinesh

    2018-03-01

    Cu2+ substituted Mg - Zn nanoferrites is synthesized by low temperature fired sol gel auto combustion method. The spinel nature of nanoferrites was confirmed by lab x-ray technique. Williamson - Hall (W-H) analysis estimate the average crystallite size (22.25-29.19 ± 3 nm) and micro strain induced Mg0.5Zn0.5-xCuxFe2O4 (0.0 ≤ x ≤ 0.5). Raman scattering measurements confirm presence of four active phonon modes. Red shift is observed with enhanced Cu concentration. Dielectric parameters exhibit a non - monotonous dispersion with Cu concentration and interpreted with the support of hopping mechanism and Maxwell-Wagner type of interfacial polarization. The ac conductivity of nanoferrites increases with raising the frequency. Complex electrical modulus reveals a non - Debye type of dielectric relaxation present in nanoferrites. Reactive impedance (Z″) detected an anomalous behavior and is related with resonance effect. Complex impedance demonstrates one semicircle corresponding to the intergrain (grain boundary) resistance and also explains conducting nature of nanoferrites. For x = 0.2, a large semicircle is observed revealing the ohmic nature (minimum potential drop at electrode surface). Dielectric properties were improved for nanoferrites with x = 0.2 and is due to high dielectric constant, conductivity and minimum loss value (∼0.009) at 1 MHz.

  19. Cooperative cytotoxic activity of Zn and Cu in bovine serum albumin-conjugated ZnS/CuS nano-composites in PC12 cancer cells

    International Nuclear Information System (INIS)

    Wang, Hua-Jie; Yu, Xue-Hong; Wang, Cai-Feng; Cao, Ying

    2013-01-01

    Series of self-assembled and mono-dispersed bovine serum albumin (BSA)-conjugated ZnS/CuS nano-composites with different Zn/Cu ratios had been successfully synthesized by a combination method of the biomimetic synthesis and ion-exchange strategy under the gentle conditions. High-resolution transmission electron microscopy observation, Fourier transform infrared spectra and zeta potential analysis demonstrated that BSA-conjugated ZnS/CuS nano-composites with well dispersity had the hierarchical structure and BSA was a key factor to control the morphology and surface electro-negativity of final products. The real-time monitoring by atomic absorption spectroscopy and powder X-ray diffraction revealed that the Zn/Cu ratio of nano-composites could be controlled by adjusting the ion-exchange time. In addition, the metabolic and morphological assays indicated that the metabolic proliferation and spread of rat pheochromocytoma (PC12) cells could be inhibited by nano-composites, with the high anti-cancer activity at a low concentration (4 ppm). What were more important, Zn and Cu in nano-composites exhibited a positive cooperativity at inhibiting cancer cell functions. The microscope observation and biochemical marker analysis clearly revealed that the nano-composites-included lipid peroxidation and disintegration of membrane led to the death of PC12 cells. Summarily, the present study substantiated the potential of BSA-conjugated ZnS/CuS nano-composites as anti-cancer drug

  20. Cooperative cytotoxic activity of Zn and Cu in bovine serum albumin-conjugated ZnS/CuS nano-composites in PC12 cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hua-Jie, E-mail: wanghuajie972001@163.com; Yu, Xue-Hong; Wang, Cai-Feng; Cao, Ying, E-mail: caoying1130@sina.com [Henan Normal University, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, College of Chemistry and Chemical Engineering (China)

    2013-11-15

    Series of self-assembled and mono-dispersed bovine serum albumin (BSA)-conjugated ZnS/CuS nano-composites with different Zn/Cu ratios had been successfully synthesized by a combination method of the biomimetic synthesis and ion-exchange strategy under the gentle conditions. High-resolution transmission electron microscopy observation, Fourier transform infrared spectra and zeta potential analysis demonstrated that BSA-conjugated ZnS/CuS nano-composites with well dispersity had the hierarchical structure and BSA was a key factor to control the morphology and surface electro-negativity of final products. The real-time monitoring by atomic absorption spectroscopy and powder X-ray diffraction revealed that the Zn/Cu ratio of nano-composites could be controlled by adjusting the ion-exchange time. In addition, the metabolic and morphological assays indicated that the metabolic proliferation and spread of rat pheochromocytoma (PC12) cells could be inhibited by nano-composites, with the high anti-cancer activity at a low concentration (4 ppm). What were more important, Zn and Cu in nano-composites exhibited a positive cooperativity at inhibiting cancer cell functions. The microscope observation and biochemical marker analysis clearly revealed that the nano-composites-included lipid peroxidation and disintegration of membrane led to the death of PC12 cells. Summarily, the present study substantiated the potential of BSA-conjugated ZnS/CuS nano-composites as anti-cancer drug.

  1. Accumulation of Cu and Zn from antifouling paint particles by the marine macroalga, Ulva lactuca

    International Nuclear Information System (INIS)

    Turner, Andrew; Pollock, Heather; Brown, Murray T.

    2009-01-01

    The marine macroalga, Ulva lactuca, has been exposed to different concentrations of antifouling paint particles (4-200 mg L -1 ) in the presence of a fixed quantity of clean estuarine sediment and its photosynthetic response and accumulation of Cu and Zn monitored over a period of 2 days. An immediate (<2 h) toxic effect was elicited under all experimental conditions that was quantitatively related to the concentration of contaminated particles present. Likewise, the rate of leaching of both Cu and Zn was correlated with the concentration of paint particles added. Copper accumulation by the alga increased linearly with aqueous Cu concentration, largely through adsorption to the cell surface, but significant accumulation of Zn was not observed. Thus, in coastal environments where boat maintenance is practiced, discarded antifouling paint particles are an important source of Cu, but not Zn, to U. lactuca. - The marine macroalga, Ulva lactuca, is able to accumulate Cu but not Zn from discarded antifouling paint particles.

  2. Effect of Cu-Dopant on the Structural, Magnetic and Electrical Properties of ZnO

    Science.gov (United States)

    Aryanto, D.; Kurniawan, C.; Subhan, A.; Sudiro, T.; Sebayang, P.; Ginting, M.; Siregar, S. M. K.; Nasruddin, M. N.

    2017-05-01

    Zn1- x Cu x O (x = 0, 2, 3, and 4 at.%) was synthesized by using solid-state reaction technique. The ZnO and CuO powders were mixed and then milled by using high-speed shaker mill. The influence of Cu dopants on the structure, magnetic, and electrical properties was investigated by using XRD, VSM, and I-V and C-V measurements. The XRD analysis showed that the Zn1- x Cu x O had hexagonal wurtzite polycrystalline. The diffraction intensity decreased and the peak position shifted directly to a higher 2θ angle with increasing the dopant concentration. Furthermore, the lattice parameters decreased when the ZnO was doped with x = 0.04, which indicated that the crystal structure changed. The increase of Cu dopants was believed to affect the magnetic and electrical properties of ZnO.

  3. Accumulation of Cu and Zn from antifouling paint particles by the marine macroalga, Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Pollock, Heather [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Brown, Murray T. [School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2009-08-15

    The marine macroalga, Ulva lactuca, has been exposed to different concentrations of antifouling paint particles (4-200 mg L{sup -1}) in the presence of a fixed quantity of clean estuarine sediment and its photosynthetic response and accumulation of Cu and Zn monitored over a period of 2 days. An immediate (<2 h) toxic effect was elicited under all experimental conditions that was quantitatively related to the concentration of contaminated particles present. Likewise, the rate of leaching of both Cu and Zn was correlated with the concentration of paint particles added. Copper accumulation by the alga increased linearly with aqueous Cu concentration, largely through adsorption to the cell surface, but significant accumulation of Zn was not observed. Thus, in coastal environments where boat maintenance is practiced, discarded antifouling paint particles are an important source of Cu, but not Zn, to U. lactuca. - The marine macroalga, Ulva lactuca, is able to accumulate Cu but not Zn from discarded antifouling paint particles.

  4. The crystallisation of Cu2ZnSnS4 thin film solar cell absorbers from co-electroplated Cu-Zn-Sn precursors

    International Nuclear Information System (INIS)

    Schurr, R.; Hoelzing, A.; Jost, S.; Hock, R.; Voss, T.; Schulze, J.; Kirbs, A.; Ennaoui, A.; Lux-Steiner, M.; Weber, A.; Koetschau, I.; Schock, H.-W.

    2009-01-01

    The best CZTS solar cell so far was produced by co-sputtering continued with vapour phase sulfurization method. Efficiencies of up to 5.74% were reached by Katagiri et al. The one step electrochemical deposition of copper, zinc, tin and subsequent sulfurization is an alternative fabrication technique for the production of Cu 2 ZnSnS 4 based thin film solar cells. A kesterite based solar cell (size 0.5 cm 2 ) with a conversion efficiency of 3.4% (AM1.5) was produced by vapour phase sulfurization of co-electroplated Cu-Zn-Sn films. We report on results of in-situ X-ray diffraction (XRD) experiments during crystallisation of kesterite thin films from electrochemically co-deposited metal films. The kesterite crystallisation is completed by the solid state reaction of Cu 2 SnS 3 and ZnS. The measurements show two different reaction paths depending on the metal ratios in the as deposited films. In copper-rich metal films Cu 3 Sn and CuZn were found after electrodeposition. In copper-poor or near stoichiometric precursors additional Cu 6 Sn 5 and Sn phases were detected. The formation mechanism of Cu 2 SnS 3 involves the binary sulphides Cu 2-x S and SnS 2 in the absence of the binary precursor phase Cu 6 Sn 5 . The presence of Cu 6 Sn 5 leads to a preferred formation of Cu 2 SnS 3 via the reaction educts Cu 2-x S and SnS 2 in the presence of a SnS 2 (Cu 4 SnS 6 ) melt. The melt phase may be advantageous in crystallising the kesterite, leading to enhanced grain growth in the presence of a liquid phase

  5. Research on Cu2ZnSnTe4 crystals and heterojunctions based on such crystals

    Directory of Open Access Journals (Sweden)

    Kovaliuk T. T.

    2015-12-01

    Full Text Available The paper reports on the results of the studies of magnetic, kinetic and optical properties of Cu2ZnSnTe4 crystals. The Cu2ZnSnTe4 crystals showed diamagnetic properties (the magnetic susceptibility almost independent of the magnetic field and temperature. The Cu2ZnSnTe4 crystals possessed p-type of conductivity and the Hall coefficient was independent on temperature. The temperature dependence of the electrical conductivity of the Cu2ZnSnTe4 crystal shows metallic character, i. e. decreases with the increase of temperature, that is caused by the lower charge carrier mobility at higher temperature. Thermoelectric power of the samples ispositive that also indicates on the prevalence of p-type conductivity. Heterojunctions n-TiN/p-Cu2ZnSnTe4, n-TiO2/p-Cu2ZnSnTe4 and n-MoO/p-Cu2ZnSnTe4 were fabricated by the reactive magnetron sputtering of TiN, TiO2 and MoOx thin films, respectively, onto the substrates made of the Cu2ZnSnTe4 crystals. The dominating current transport mechanisms in the n-TiN/p-Cu2ZnSnTe4 and n-TiO2/p-Cu2ZnSnTe4 heterojunctions were established to be the tunnel-recombination mechanism at forward bias and tunneling at reverse bias.

  6. Thermochemistry of paddle wheel MOFs: Cu-HKUST-1 and Zn-HKUST-1.

    Science.gov (United States)

    Bhunia, Manas K; Hughes, James T; Fettinger, James C; Navrotsky, Alexandra

    2013-06-25

    Metal-organic framework (MOF) porosity relies upon robust metal-organic bonds to retain structural rigidity upon solvent removal. Both the as-synthesized and activated Cu and Zn polymorphs of HKUST-1 were studied by room temperature acid solution calorimetry. Their enthalpies of formation from dense assemblages (metal oxide (ZnO or CuO), trimesic acid (TMA), and N,N-dimethylformamide (DMF)) were calculated from the calorimetric data. The enthalpy of formation (ΔHf) of the as-synthesized Cu-HKUST-H2O ([Cu3TMA2·3H2O]·5DMF) is -52.70 ± 0.34 kJ per mole of Cu. The ΔHf for Zn-HKUST-DMF ([Zn3TMA2·3DMF]·2DMF) is -54.22 ± 0.57 kJ per mole of Zn. The desolvated Cu-HKUST-dg [Cu3TMA2] has a ΔHf of 16.66 ± 0.51 kJ/mol per mole Cu. The ΔHf for Zn-HKUST-amorph [Zn3TMA2·2DMF] is -3.57 ± 0.21 kJ per mole of Zn. Solvent stabilizes the Cu-HKUST-H2O by -69.4 kJ per mole of Cu and Zn-HKUST-DMF by at least -50.7 kJ per mole of Zn. Such strong chemisorption of solvent is similar in magnitude to the strongly exothermic binding at low coverage for chemisorbed H2O on transition metal oxide nanoparticle surfaces. The strongly exothermic solvent-framework interaction suggests that solvent can play a critical role in obtaining a specific secondary building unit (SBU) topology.

  7. Kinetics of methanol decomposition on Cu/ZnO/ZrO2 catalysts

    International Nuclear Information System (INIS)

    Grabowski, R.; Kozlowska, A.

    2004-01-01

    Interaction of methanol with Cu/ZnO/ZrO 2 (with different copper content) has been investigated by gravimetric and TPD methods. The TPD measurements of methanol adsorption on these catalysis show that it forms the complexes of two types. The first complex (I) decomposes at low temperature (453 K) yielding H 2 and CO 2 and second (II) decomposes at temperature (573 K) giving CO and H 2 . In the process of decomposition of the complex (I) takes part water which is adsorbed on the surface of the catalyst and the decomposition of the complex (II) occurs without participation of adsorbed water. Gravimetric measurements of methanol and that an increase of copper content leads to the changes in the kinetics of methanol adsorption and its decomposition. On the basis of gravimetric measurements a model of methanol adsorption and decomposition on Cu/ZnO/ZrO 2 catalyst has been proposed and the rate constants of methanol adsorption (k a ) and decomposition with and without participation of water (k 1 and k 2 ) have been determined. (author)

  8. Ag-CuO-ZnO metal-semiconductor multiconcentric nanotubes for achieving superior and perdurable photodegradation.

    Science.gov (United States)

    Xu, Kaichen; Wu, Jiagen; Tan, Chuan Fu; Ho, Ghim Wei; Wei, Ang; Hong, Minghui

    2017-08-17

    Solar energy represents a robust and natural form of resource for environment remediation via photocatalytic pollutant degradation with minimum associated costs. However, due to the complexity of the photodegradation process, it has been a long-standing challenge to develop reliable photocatalytic systems with low recombination rates, excellent recyclability, and high utilization rates of solar energy, especially in the visible light range. In this work, a ternary hetero-nanostructured Ag-CuO-ZnO nanotube (NT) composite is fabricated via facile and low-temperature chemical and photochemical deposition methods. Under visible light irradiation, the as-synthesized ZnO NT based ternary composite exhibits a greater enhancement (∼300%) of photocatalytic activity than its counterpart, Ag-CuO-ZnO nanorods (NRs), in pollutant degradation. The enhanced photocatalytic capability is primarily attributed to the intensified visible light harvesting, efficient charge carrier separation and much larger surface area. Furthermore, our as-synthesised hybrid ternary Ag-CuO-ZnO NT composite demonstrates much higher photostability and retains ∼98% of degradation efficiency even after 20 usage cycles, which can be mainly ascribed to the more stable polar planes of ZnO NTs than those of ZnO NRs. These results afford a new route to construct ternary heterostructured composites with perdurable performance in sewage treatment and photocorrosion suppression.

  9. Fabrication and characterization of Pd/Cu doped ZnO/Si and Ni/Cu doped ZnO/Si Schottky diodes

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Lucky; Singh, Brijesh Kumar; Tripathi, Shweta [Department of Electronics & Communication Engineering, Motilal Nehru National Institute of Technology, Allahabad 211004 (India); Chakrabarti, P., E-mail: pchakrabarti.ece@iitbhu.ac.in [Department of Electronics & Communication Engineering, Motilal Nehru National Institute of Technology, Allahabad 211004 (India); Department of Electronics Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005 (India)

    2016-08-01

    In this paper, fabrication and characterization of copper doped ZnO (Cu doped ZnO) based Schottky devices have been reported. Cu doped ZnO thin films have been deposited on p-Si (100) samples by the sol-gel spin coating method. X-Ray diffraction (XRD) and atomic force microscopy (AFM) studies have been done in order to evaluate the structural and morphological properties of the film. The optical properties of the film have been determined by using variable angle ellipsometry. Further, Seebeck measurement of the deposited Cu doped ZnO film leads to positive Seebeck coefficient confirming the p-type conductivity of the sample. The resistivity and acceptor concentration of the film has also been evaluated using four probe measurement system. Pd and Ni metals have been deposited on separate Cu doped ZnO thin film samples using low cost thermal evaporation method to form Schottky contacts. The electrical characterization of the Schottky diode has been performed by semiconductor device analyzer (SDA). Electrical parameters such as barrier height, ideality factor, reverse saturation current and rectification ratio have also been determined for the as-prepared Schottky diode using conventional thermionic emission model and Cheung's method. - Highlights: • Fabrication of sol-gel derived Cu doped ZnO (p-type) Schottky contact proposed. • The p-type Conductivity of the sample confirmed by Seebeck Measurement. • Pd and Ni deposited on Cu doped ZnO film to form Schottky contacts. • Cu doped ZnO expected to emerge as a potential material for thin film solar cells.

  10. Fabrication and characterization of Pd/Cu doped ZnO/Si and Ni/Cu doped ZnO/Si Schottky diodes

    International Nuclear Information System (INIS)

    Agarwal, Lucky; Singh, Brijesh Kumar; Tripathi, Shweta; Chakrabarti, P.

    2016-01-01

    In this paper, fabrication and characterization of copper doped ZnO (Cu doped ZnO) based Schottky devices have been reported. Cu doped ZnO thin films have been deposited on p-Si (100) samples by the sol-gel spin coating method. X-Ray diffraction (XRD) and atomic force microscopy (AFM) studies have been done in order to evaluate the structural and morphological properties of the film. The optical properties of the film have been determined by using variable angle ellipsometry. Further, Seebeck measurement of the deposited Cu doped ZnO film leads to positive Seebeck coefficient confirming the p-type conductivity of the sample. The resistivity and acceptor concentration of the film has also been evaluated using four probe measurement system. Pd and Ni metals have been deposited on separate Cu doped ZnO thin film samples using low cost thermal evaporation method to form Schottky contacts. The electrical characterization of the Schottky diode has been performed by semiconductor device analyzer (SDA). Electrical parameters such as barrier height, ideality factor, reverse saturation current and rectification ratio have also been determined for the as-prepared Schottky diode using conventional thermionic emission model and Cheung's method. - Highlights: • Fabrication of sol-gel derived Cu doped ZnO (p-type) Schottky contact proposed. • The p-type Conductivity of the sample confirmed by Seebeck Measurement. • Pd and Ni deposited on Cu doped ZnO film to form Schottky contacts. • Cu doped ZnO expected to emerge as a potential material for thin film solar cells.

  11. Petrography, geochemistry and genesis of the Skiftesmyr Cu-Zn VMS deposit, Grong, Norway

    OpenAIRE

    Walsh, Kristoffer Jøtne

    2013-01-01

    The Skiftesmyr Cu-Zn VMS-deposit is located in the Grong municipality of Northern Trøndelag, Norway. The mineralization has been known since at least 1903, when mention of small workings in the area were first published, and has later been the subject of several exploration projects by different companies, of which MetPro AS is the latest. The Skiftesmyr deposit is a part of the Gjersvik Nappe, which is a part of the Köli Nappe Complex, which in turn is a part of the Upper Allo...

  12. First-principle Calculations of Mechanical Properties of Al2Cu, Al2CuMg and MgZn2 Intermetallics in High Strength Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    LIAO Fei

    2016-12-01

    Full Text Available Structural stabilities, mechanical properties and electronic structures of Al2Cu, Al2CuMg and MgZn2 intermetallics in Al-Zn-Mg-Cu aluminum alloys were determined from the first-principle calculations by VASP based on the density functional theory. The results show that the cohesive energy (Ecoh decreases in the order MgZn2 > Al2CuMg > Al2Cu, whereas the formation enthalpy (ΔH decreases in the order MgZn2 > Al2Cu > Al2CuMg. Al2Cu can act as a strengthening phase for its ductile and high Young's modulus. The Al2CuMg phase exhibits elastic anisotropy and may act as a crack initiation point. MgZn2 has good plasticity and low melting point, which is the main strengthening phase in the Al-Zn-Mg-Cu aluminum alloys. Metallic bonding mode coexists with a fractional ionic interaction in Al2Cu, Al2CuMg and MgZn2, and that improves the structural stability. In order to improve the alloys' performance further, the generation of MgZn2 phase should be promoted by increasing Zn content while Mg and Cu contents are decreased properly.

  13. Study on positron annihilation spectroscopy of methanol synthesis catalyst CuO/ZnO

    International Nuclear Information System (INIS)

    Liu Qisheng; Dai Guohuan; Sun Jiying; Ding Yingru; Yao Jianhua

    1989-01-01

    A new method was developed for determining the solid solubility of a metal oxide series prepared by precipitation using the positron lifetime parameters. The positron lifetime spectra of a series of CuO/ZnO catalysts prepared by precipitation were measured, in which the CuO at % contents were different before and after reducing. The relations between the solid solubility of the catalysts and the positron lifetime parameters were obtained, from which a result of solid solubility of 12 CuO at% after reducing had been found. The viewpoint that the Cu + ion acted as the active centre in the CuO/ZnO catalyst was supported

  14. Size Control of Alloyed Cu-In-Zn-S Nanoflowers

    Directory of Open Access Journals (Sweden)

    Björn Kempken

    2015-01-01

    Full Text Available Uniform, alloyed Cu-In-Zn-S nanoflowers with sizes of 11.5±2.1 nm and 31±5 nm composed of aggregated 4.1 nm and 5.6 nm primary crystallites, respectively, were obtained in a one-pot, heat-up reaction between copper, indium, and zinc acetate with tert-dodecanethiol in the presence of trioctylphosphine oxide. Larger aggregates were obtained by diluting tert-dodecanethiol with oleylamine, which lowered the reactivity of the indium and zinc precursors and led to the formation of copper rich particles. The thermal decomposition of tert-dodecanethiol stabilizing the primary crystallites induced their agglomeration, while the presence of trioctylphosphine oxide on the surface of the nanoflowers provided them with colloidal stability and prevented them from further aggregation.

  15. Thermoelastic properties on Cu-Zn-Al shape memory springs

    Directory of Open Access Journals (Sweden)

    Carlos Augusto do Nascimento Oliveira

    2010-06-01

    Full Text Available This paper present a thermomechanical study of actuators in form of helical springs made from shape memory alloy wires that can work as actuator and/or as sensor. These abilities are due to the martensitic transformation. This transformation is a diffusionless phase transition that occurs by a cooperative atomic rearrange mechanism. In this work, helical spring actuators were manufactured from Cu-Zn-Al shape memory alloy wires. The springs were submitted to constant tensile loads and thermal cycles. This procedure allows to determine thermoelastic properties of the shape memory springs. Thermomechanical properties were analyzed during 50 thermal cycles in the temperature range from 20 to 130 °C. Results of variations in critical transformation temperatures, thermoelastic strain and thermal hysteresis are discussed based on defects rearrangement and martensitic transformation theory.

  16. Enhanced bake-hardening response of an Al–Mg–Si–Cu alloy with Zn addition

    Energy Technology Data Exchange (ETDEWEB)

    Guo, M.X., E-mail: mingxingguo@skl.ustb.edu.cn [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China); Sha, G., E-mail: gang.sha@njust.edu.cn [School of Materials Science and Engineering, Nanjing University of Science and Technology, Jiangsu 210094 (China); Cao, L.Y. [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China); Liu, W.Q. [Key Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China); Zhang, J.S.; Zhuang, L.Z. [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-07-15

    This study reports that Zn addition greatly enhances the bake-hardening response of an Al–Mg–Si–Cu alloy. The pre-aged alloy exhibits a high strength increment of 135 MPa after paint baking. Differential scanning calorimetry, atom probe tomography and high-resolution transmission electron microscopy reveal that Zn addition and pre-aging have significant effects on the solute nanostructure formation. Zn atoms partition into solute clusters/GP zones, and reduce the activation energy of β” precipitation in the alloy. - Highlights: • Zn addition can improve the bake-hardening response of an Al–Mg–Si–Cu alloy. • Zn addition can stabilize the solute clusters/GP zones from dissolution. • Zn addition can reduce the size of clusters formed in the pre-aging treatment. • Zn partitioned into solute clusters/GP zones and β” in the Zn-containing Al alloy.

  17. Non-isothermal precipitation behaviors of Al-Mg-Si-Cu alloys with different Zn contents

    International Nuclear Information System (INIS)

    Guo, M.X.; Zhang, Y.; Zhang, X.K.; Zhang, J.S.; Zhuang, L.Z.

    2016-01-01

    The non-isothermal precipitation behaviors of Al–Mg–Si–Cu alloys with different Zn contents were investigated by differential scanning calorimetry (DSC) analysis, hardness measurement and high resolution transmission electron microscope characterization. The results show that Zn addition has a significant effect on the GP zone dissolution and precipitation of Al-Mg-Si-Cu alloys. And their activation energies change with the changes of Zn content and aging conditions. Precipitation kinetics can be improved by adding 0.5 wt% or 3.0 wt%Zn, while be suppressed after adding 1.5 wt%Zn. The Mg-Si precipitates (GP zones and β″) are still the main precipitates in the Al-Mg-Si-Cu alloys after heated up to 250 °C, and no Mg-Zn precipitates are observed in the Zn-added alloy due to the occurrence of Mg-Zn precipitates reversion. The measured age-hardening responses of the alloys are corresponding to the predicted results by the established precipitation kinetic equations. Additionally, a double-hump phenomenon of hardness appears in the artificial aging of pre-aged alloy with 3.0 wt% Zn addition, which resulted from the formation of pre-β″ and β″ precipitates. Finally, the precipitation mechanism of Al-Mg-Si-Cu alloys with different Zn contents was proposed based on the microstructure evolution and interaction forces between Mg, Si and Zn atoms.

  18. Ni(ii)/Cu(ii)/Zn(ii) 5,5-diethylbarbiturate complexes with 1,10-phenanthroline and 2,2'-dipyridylamine: synthesis, structures, DNA/BSA binding, nuclease activity, molecular docking, cellular uptake, cytotoxicity and the mode of cell death.

    Science.gov (United States)

    Yilmaz, Veysel T; Icsel, Ceyda; Suyunova, Feruza; Aygun, Muhittin; Aztopal, Nazlihan; Ulukaya, Engin

    2016-06-21

    New 5,5-diethylbarbiturate (barb) complexes of Ni(ii), Cu(ii) and Zn(ii) with 1,10-phenanthroline (phen) and 2,2'-dipyridylamine (dpya), namely [Ni(phen-κN,N')3]Cl(barb)·7H2O (), [Cu(barb-κN)(barb-κ(2)N,O)(phen-κN,N')]·H2O (), [Cu(barb-κN)2(phen-κN,N')] (), [Zn(barb-κN)2(phen-κN,N')]·H2O (), [Ni(barb-κ(2)N,O)(dpya-κN,N')2]Cl·2H2O (), [Cu(barb-κ(2)N,O)2(dpya-κN,N')]·2H2O () and [Zn(barb-κN)2(dpya-κN,N')] (), were synthesized and characterized by elemental analysis, UV-vis, FT-IR and ESI-MS. The structures of the complexes were determined by X-ray crystallography. Notably, and were fluorescent in MeOH : H2O at rt. The interaction of the complexes with fish sperm (FS) DNA and bovine serum albumin (BSA) was investigated in detail by various techniques. The complexes exhibited groove binding along with a partial intercalative interaction with DNA, while the hydrogen bonding and hydrophobic interactions played a major role in binding to BSA. It is noteworthy that exhibited the highest affinity towards DNA and BSA. Enzyme inhibition assay showed that show a preference for both A/T and G/C rich sequences in pUC19 DNA, while and display a binding specificity to the G/C and A/T rich regions, respectively. These findings were further supported by molecular docking. The cellular uptake studies suggested that was deposited mostly in the membrane fraction of the cells. Among the present complexes, exhibited a very strong cytotoxic effect on A549, MCF-7, HT-29 and DU-145 cancer cells, being more potent than cisplatin. Moreover, induces cell death through the apoptotic mode obtained by flow cytometry.

  19. Investigations of structural, morphological and optical properties of Cu:ZnO/TiO2/ZnO and Cu:TiO2/ZnO/TiO2 thin films prepared by spray pyrolysis technique

    Directory of Open Access Journals (Sweden)

    M.I. Khan

    Full Text Available The aim of this research work is presented a comparison study of Cu:ZnO/TiO2/ZnO (Cu:ZTZ and Cu:TiO2/ZnO/TiO2 (Cu:TZT thin films deposited by spray pyrolysis technique on FTO substrates. After deposition, these films are annealed at 500 °C. XRD confirms the anatase phase of TiO2 and Hexagonal wurtzite phase of ZnO. SEM shows that Cu:TZT has more porous surface than Cu:ZTZ and also the root mean square (RMS roughness of Cu:TZT film is 48.96 and Cu:ZTZ film is 32.69. The calculated optical band gaps of Cu:TZT and Cu:ZTZ thin films are 2.65 eV and 2.6 eV respectively, measured by UV–Vis spectrophotometer. This work provides an environment friendly and low cost use of an abundant material for highly efficient dye sensitized solar cells (DSSCs. Keywords: Multilayer films, ZnO, TiO2, Cu

  20. Effects of Cu(2+) and Zn(2+) on growth and physiological characteristics of green algae, Cladophora.

    Science.gov (United States)

    Cao, De-ju; Xie, Pan-pan; Deng, Juan-wei; Zhang, Hui-min; Ma, Ru-xiao; Liu, Cheng; Liu, Ren-jing; Liang, Yue-gan; Li, Hao; Shi, Xiao-dong

    2015-11-01

    Effects of various concentrations of Cu(2+) and Zn(2+) (0.0, 0.1, 0.25, 0.5, or 1.0 mg/L) on the growth, malondialdehyde (MDA), the intracellular calcium, and physiological characteristics of green algae, Cladophora, were investigated. Low Zn(2+) concentrations accelerated the growth of Cladophora, whereas Zn(2+) concentration increases to 0.25 mg/L inhibited its growth. Cu(2+) greatly influences Cladophora growth. The photosynthesis of Cladophora decreased under Zn(2+) and Cu(2+) stress. Cu(2+) and Zn(2+) treatment affected the content of total soluble sugar in Cladophora and has small increases in its protein content. Zn(2+) induced the intracellular calcium release, and copper induced the intracellular calcium increases in Cladophora. Exposure to Cu(2+) and Zn(2+) induces MDA in Cladophora. The stress concent of Cu(2+) was strictly correlated with the total soluble sugar content, Chla+Chlb, and MDA in Cladophora, and the stress concent of Zn(2+) was strictly correlated with the relative growth rate (RGR) and MDA of Cladophora.

  1. Molecular Cloning and Expression Analysis of Cu/Zn SOD Gene from Gynura bicolor DC.

    Directory of Open Access Journals (Sweden)

    Xin Xu

    2017-01-01

    Full Text Available Superoxide dismutase is an important antioxidant enzyme extensively existing in eukaryote, which scavenges reactive oxygen species (ROS and plays an essential role in stress tolerance of higher plants. A full-length cDNA encoding Cu/Zn SOD was cloned from leaves of Gynura bicolor DC. by rapid amplification of cDNA ends (RACE. The full-length cDNA of Cu/Zn SOD is 924 bp and has a 681 bp open reading frame encoding 227 amino acids. Bioinformatics analysis revealed that belonged to the plant SOD super family. Cu/Zn SODs of the Helianthus annuus, Mikania micrantha, and Solidago canadensis var. scabra all have 86% similarity to the G. bicolor Cu/Zn SOD. Analysis of the expression of Cu/Zn SOD under different treatments revealed that Cu/Zn SOD was a stress-responsive gene, especially to 1-MCP. It indicates that the Cu/Zn SOD gene would be an important gene in the resistance to stresses and will be helpful in providing evidence for future research on underlying molecular mechanism and choosing proper postharvest treatments for G. bicolor.

  2. Tracing contamination sources in soils with Cu and Zn isotopic ratios.

    Science.gov (United States)

    Fekiacova, Z; Cornu, S; Pichat, S

    2015-06-01

    Copper (Cu) and zinc (Zn) are naturally present and ubiquitous in soils and are important micronutrients. Human activities contribute to the input of these metals to soils in different chemical forms, which can sometimes reach a toxic level for soil organisms and plants. Isotopic signatures could be used to trace sources of anthropogenic Cu and Zn pollution. The aim of this paper is to determine whether it is possible to identify (i) Cu and Zn contamination in soils and their sources, on the basis of their isotopic signatures, and (ii) situations that are a priori favorable or not for tracing Cu and Zn pollution using the isotopic approach. Therefore, we compiled data from the literature on Cu and Zn isotopes in soils, rocks and pollutants and added to this database the results of our own research. As only a few studies have dealt with agricultural contamination, we also studied a soil toposequence from Brittany, France, that experienced spreading of pig slurry for tens of years. In the surface horizons of the natural soils, the δ(65)Cu values vary from -0.15 to 0.44‰ and the δ(66)Zn from -0.03 to 0.43‰. Furthermore, vertical variations along soil profiles range from -0.95 to 0.44‰ for δ(65)Cu and from -0.53 to 0.64‰ for δ(66)Zn values. We concluded that pedogenetic processes can produce isotopic fractionation, yet, it is not always discernible and can be overprinted by an exogenous isotopic signature. Furthermore, some contaminants are enriched in heavy Cu or in light Zn compared to the rock or soil, but no generalization can be made. The anthropogenic inputs can be identified based on stable Cu and Zn isotope ratios if the isotope ratios of the sources are different from those of the soil, which needs to be tested for each individual case. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Performance evaluation of ZnO–CuO hetero junction solid state room temperature ethanol sensor

    International Nuclear Information System (INIS)

    Yu, Ming-Ru; Suyambrakasam, Gobalakrishnan; Wu, Ren-Jang; Chavali, Murthy

    2012-01-01

    Graphical abstract: Sensor response (resistance) curves of time were changed from 150 ppm to 250 ppm alcohol concentration of ZnO–CuO 1:1. The response and recovery times were measured to be 62 and 83 s, respectively. The sensing material ZnO–CuO is a high potential alcohol sensor which provides a simple, rapid and highly sensitive alcohol gas sensor operating at room temperature. Highlights: ► The main advantages of the ethanol sensor are as followings. ► Novel materials ZnO–CuO ethanol sensor. ► The optimized ZnO–CuO hetero contact system. ► A good sensor response and room working temperature (save energy). -- Abstract: A semiconductor ethanol sensor was developed using ZnO–CuO and its performance was evaluated at room temperature. Hetero-junction sensor was made of ZnO–CuO nanoparticles for sensing alcohol at room temperature. Nanoparticles were prepared by hydrothermal method and optimized with different weight ratios. Sensor characteristics were linear for the concentration range of 150–250 ppm. Composite materials of ZnO–CuO were characterized using X-ray diffraction (XRD), temperature-programmed reduction (TPR) and high-resolution transmission electron microscopy (HR-TEM). ZnO–CuO (1:1) material showed maximum sensor response (S = R air /R alcohol ) of 3.32 ± 0.1 toward 200 ppm of alcohol vapor at room temperature. The response and recovery times were measured to be 62 and 83 s, respectively. The linearity R 2 of the sensor response was 0.9026. The sensing materials ZnO–CuO (1:1) provide a simple, rapid and highly sensitive alcohol gas sensor operating at room temperature.

  4. First-principles calculations of vacancy formation in In-free photovoltaic semiconductor Cu2ZnSnSe4

    International Nuclear Information System (INIS)

    Maeda, Tsuyoshi; Nakamura, Satoshi; Wada, Takahiro

    2011-01-01

    To quantitatively evaluate the formation energies of Cu, Zn, Sn, and Se vacancies in kesterite-type Cu 2 ZnSnSe 4 (CZTSe), first-principles pseudopotential calculations using plane-wave basis functions were performed. The formation energies of neutral Cu, Zn, Sn and Se vacancies were calculated as a function of the atomic chemical potentials of constituent elements. The obtained results were as follows: (1) the formation energy of Cu vacancy was generally smaller than those of the other Zn, Sn and Se vacancies, (2) under the Cu-poor and Zn-rich condition, the formation energy of Cu vacancy was particularly low, (3) the formation energy of Zn vacancy greatly depended on the chemical potentials of the constituent elements and under the Zn-poor and Se-rich condition, the formation energy of Zn vacancy was smaller than that of Cu vacancy, and (4) the formation energy of Sn vacancy did not greatly depend on the chemical potentials of the constituent elements and was much larger than those of Cu, Zn, and Se vacancies. These results indicate that Cu vacancy is easily formed under Cu-poor and Zn-rich conditions, but Zn vacancy is easily formed under the Zn-poor and Se-rich conditions.

  5. Improved photocatalytic activity of ZnO coupled CuO nanocomposites synthesized by reflux condensation method

    International Nuclear Information System (INIS)

    Mageshwari, K.; Nataraj, D.; Pal, Tarasankar; Sathyamoorthy, R.; Park, Jinsub

    2015-01-01

    Highlights: • CuO–ZnO nanocomposites were synthesized by reflux condensation method. • Photodegradation of methyl orange and methylene blue dyes was investigated. • Morphological studies show 3D flower-like CuO microspheres adorned with ZnO nanorods. • Optical analysis showed characteristic absorption bands of CuO and ZnO. • CuO–ZnO nanocomposites exhibited superior photocatalytic activity than CuO. - Abstract: Nanostructured CuO–ZnO nanocomposites were successfully synthesized for different Zn 2+ concentrations by reflux condensation method without using any surfactant, and their photocatalytic activity was evaluated using methyl orange and methylene blue dyes under UV light irradiation. XRD revealed the formation of CuO–ZnO nanocomposites, composing of monoclinic CuO and hexagonal ZnO. XPS analysis revealed that CuO–ZnO nanocomposites are made up of Cu(II), Zn(II) and O. FESEM and TEM images showed that pure CuO exhibit 3D flower-like microstructure, while the CuO–ZnO nanocomposites prepared for different Zn 2+ concentrations have 3D flower-like CuO, microstructure adorned with rod-like ZnO particles. UV–Vis DRS showed absorption bands corresponding to CuO and ZnO around 960 nm and 395 nm, respectively. PL spectra of CuO–ZnO nanocomposites exhibited reduced PL emissions compared to pure CuO, indicating the low recombination rate of photogenerated electrons and holes. Photodegradation assay revealed that catalytic activity of CuO–ZnO nanocomposites increased with Zn 2+ concentration, and also effectively degrade methyl orange and methylene blue dyes when compared to pure CuO. The enhanced photocatalytic activity of CuO–ZnO nanocomposites were mainly ascribed to the reduced recombination and efficient separation of photogenerated charge carriers. The possible mechanism for the improved photocatalytic activity of CuO–ZnO nanocomposites was proposed

  6. Cu and Zn Isotopes as New Tracers of Early Solar Nebula and Asteroidal processes

    Science.gov (United States)

    LUCK, J.; BEN OTHMAN, D.; ALBAREDE, F.

    2001-12-01

    Cu and Zn isotopic variations are now identified in extra-terrestrial samples, as has been the case for terrestrial samples (1). The main parameters which may cause these variations are : redox state, temperature, biological activity (Earth), and volatility (extra-terrestrial samples). We report data for meteorites from various groups and classes, including carbonaceous chondrites, ordinary and diffentiated chondrites (iron meteorites, SNC and HED). All analyses have been duplicated (from powder aliquot to final measurement). Values are expressed as relative deviations from NIST and JMC standards for 65Cu/63Cu and 66Zn64Zn, respectively (deltas in permil). Carefull chemistry and MC-ICP-MS measurements allow an overall precision of +/-0.04 permil. I- Carbonaceous Chondrites A very important feature is that each group seems to exhibit a specific isotopic signature : Cu gets isotopically lighter from CI to CM to CO to CV, spanning an overall range of 1.5 permil. Zn shows a reverse order, getting heavier from CI to CM to CO. Zn in CV chondrites (whole rock) seems more variable. This order is the same as that observed for trace elements. Cu and Zn isotopic compositions are generally correlated to trace element content from one group to another, particularly those of similar volatility (e.g. Mn for Cu; Ge for Zn). Cu and Zn isotopic signatures exhibit remarkable relationships with Oxygen isotopes. Each group is well identified. Cu is linearly correlated with Oxygen, whereas Zn-O data display strong curvature : the difference in shape can be related to the nearly constant Cu content in all groups, and by the decreasing Zn content from CI to CO. Since Oxygen variations (from CV to CI) are thought to reflect progressive interaction of liquid water with initial solid (asteroid), Cu isotopic variations may also reflect this progressive alteration process. It may be so for Zn too, although its more volatile character might play a role. II-Allende Progressive leaching

  7. Synthesis and characterization of heterobinuclear (La-Zn, Pr-Zn, Nd-Zn, Sm-Zn, Eu-Zn, Gd-Zn, Tb-Zn, Dy-Zn) azine-bridged complexes

    International Nuclear Information System (INIS)

    Singh, Bachcha; Srivastav, A.K.; Singh, P.K.

    1997-01-01

    Zinc(II) complex of 2-acetylpyridine salicyl aldazine (Haps) of the type Zn(aps) 2 (H 2 O) 2 has been synthesised. The reaction of Zn(aps) 2 (H 2 O) 2 with lanthanide chlorides, LnCl 3 (where Ln=La, Pr, Nd, Sm, Eu, Gd, Tb and Dy) yields azine-bridged heterobinuclear complexes of the formulae LnCl 3 Zn(aps) 2 (H 2 O) 2 . These complexes have been characterized by elemental analyses, molecular weight, conductance (solid and solution) and magnetic susceptibility measurements, mass, IR and electronic spectral data. X-ray powder diffraction data indicate the tetragonal unit lattice for Zn(aps) 2 (H 2 O) 2 and PrCl 3 Zn(aps) 2 (H 2 O) 2 . (author)

  8. Cu-Zn-Pb multi isotopic characterization of a small watershed (Loire river basin, France)

    Science.gov (United States)

    Desaulty, A. M.; Millot, R.; Perret, S.; Bourrain, X.

    2015-12-01

    Combating metal pollution in surface water is a major environmental, public health and economic issue. Knowledge of the behavior of metals, such as copper (Cu), zinc (Zn) and lead (Pb) in sediments and dissolved load, is a key factor to improve the management of rivers. Recent advances in mass spectrometry related to the development of MC-ICPMS allow to analyze the isotopic composition of these elements, and previous studies show the effectiveness of isotopic analyses to determine the anthropogenic sources of pollution in environment. The goal of this study is to use the Cu-Zn-Pb multi-isotopic signature to track the pollutions in surface water, and to understand the complex processes causing the metals mobilization and transport in environment. More particularly we investigate the mechanisms of distribution between the dissolved load and particulate load, known to play an important role in the transport of metals through river systems. As case study, we chose a small watershed, poorly urbanized in the Loire river basin. Its spring is in a pristine area, while it is only impacted some kilometers further by the releases rich in metals coming from a hospital water treatment plant. First a sampling of these liquid effluents as well as dissolved load and sediment from upstream to downstream was realized and their concentrations and isotopic data were determined. Then to simulate a lot of potential natural and anthropogenic modifications of environmental conditions, we made sequential extraction protocol using various reagents on the sediments. Isotopic analyzes were performed also on the various extracting solutions. Isotopic ratios were measured using a Neptune MC-ICPMS at the BRGM, after a protocol of purification for Zn and Cu. The results showed that, these isotopic systematics reveal important informations about the mechanists of mobilization and transport of metals through river systems. However experiments performed under laboratory conditions will be necessary

  9. Facile synthesis of Zn doped CuO hierarchical nanostructures: Structural, optical and antibacterial properties

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Javed, E-mail: tariqjan84@gmail.com, E-mail: javed.suggau@iiu.edu.pk; Jan, Tariq, E-mail: tariqjan84@gmail.com, E-mail: javed.suggau@iiu.edu.pk; Ul-Hassan, Sibt; Umair Ali, M.; Abbas, Fazal [Laboratory of Nanoscience and Technology, Department of Physics, International Islamic University, H-10, Islamabad (Pakistan); Ahmed, Ishaq [Experimental Physics Labs, National Center for Physics, Islamabad (Pakistan); Mansoor, Qaisar; Ismail, Muhammad [Institute of Biomedical and Genetic Engineering (IBGE), Islamabad (Pakistan)

    2015-12-15

    Zn{sub x}Cu{sub 1−x}O (where x= 0, 0.01, 0.03, 0.05, 0.07 and 0.1 mol%) hierarchical nanostructures have been prepared via soft chemical route. X-ray diffraction (XRD) results of the synthesized samples reveal the monoclinic structure of CuO without any impurity related phases. The micro-structural parameters such as crystallite size and microstrain have been strongly influenced by Zn doping. Scanning electron microscope (SEM) analyses depict the formation of hierarchical nanostructures having average particle size in the range of 26-43 nm. The surface area of CuO nanostructures has been reduced systematically with the increase in Zn content which is linked with the variations in particle size. An obvious decrease in the optical band gap energy of the synthesized CuO hierarchical nanostructures has been observed with Zn doping which is assigned to the formation of shallow levels in the band gap of CuO and combined transition from oxygen 2p states to d sates of Cu and Zn ions. The bactericidal potency of the CuO hierarchical nanostructures have been found to be enhanced remarkably with Zn doping.

  10. Design, synthesis, characterization and antibacterial and antifungal activity of a new 2-{(E-[(4-aminophenylimino]-methyl}-4,6-dichlorophenol and its complexes with Co(II, Ni(II, Cu(II and Zn(II: An experimental and DFT study

    Directory of Open Access Journals (Sweden)

    Bakirdere Emine Gulhan

    2016-01-01

    Full Text Available In this study, the complexes of Co (II, Ni (II, Cu (II and Zn (II with 2-(E-(4-aminophenyliminomethyl-4,6-dichlorophenol were prepared and characterized by physical, spectral and analytical data. The metal: ligand stoichiometric ratio is 1:2 in all the complexes. The results suggested that the Schiff bases are coordinated to the metal ions through the phenolic oxygens and azomethine nitrogen to give mononuclear complexes. Their structures were elucidated on the basis of elemental analysis, IR, 1H and 13C NMR spectra, UV-VIS, magnetic susceptibility measurements and thermogravimetric analyses. Both the antibacterial and antifungal activities and MIC values of compounds were reported. Among the tested compounds, the most effective compound providing a MIC value of 64 μg/mL is Zn(L2 against C. tropicalis and B. subtilis. The theoretically optimized geometries of complexes have tetrahedral structures. The computed stretching frequencies of C=N, C-O and N-H bonds were found to be in good agreement with experimental data. All calculated frequencies fall within about 5% of the experimental frequency regions.

  11. Photoemission studies of zinc-noble metal alloys: Zn--Cu, Zn--Ag, and Zn--Au films on Ru(001)

    International Nuclear Information System (INIS)

    Rodriguez, J.A.; Hrbek, J.

    1993-01-01

    Zn and the noble metals alloy when coadsorbed on Ru(001). The properties of Zn--Cu, Zn--Ag, and Zn--Au alloys have been studied using core- and valence-level photoemission and temperature programmed desorption. Alloy formation induces only small shifts (-0.2 to -0.3 eV) in the position of the Zn 2p, 3s, and 3d levels. In contrast, the core and valence levels of the noble metals show large shifts toward higher binding energy. For small amounts of Cu, Ag, and Au dissolved in Zn multilayers, the shifts in the core levels of the nobel metals follow the sequence: Cu(2p 3/2 ), 0.8 eV∼Ag(3d 5/2 ), 0.8 eV 7/2 ), 1.4 eV. The magnitude of the shift increases as the Pauling electronegativity of the noble metal increases. However, the sign of the shifts for the Cu(2p 3/2 ), Ag(3d 5/2 ), or Au(4f 7/2 ) levels is not directly determined by the direction of charge transfer within the corresponding Zn-noble metal bond

  12. Nanoparticles from Cu-Zn-Al shape memory alloys physically synthesized by ion milling deposition

    Energy Technology Data Exchange (ETDEWEB)

    Pavon, Luis Alberto Lopez [Universidad Autonoma de Nuevo Leon (UANL), Nuevo Leon (Mexico); Cuellara, Enrique Lopez; Castro, Alejandro Torres; Cruza, Azael Martinez de la [Universidad Autonoma de Nuevo Leon (CIIDIT/UANL), Nuevo Leon (Mexico). Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia; Ballesteros, Carmen [Universidad Carlos III de Madrid, Madrid (Spain). Departamento de Fisica; Araujo, Carlos Jose de [Universidade Federal de Campina Grande (UFCG), Campina Grande, PB (Brazil). Departamento de Engenharia Mecanica

    2012-05-15

    In this research, an ion milling equipment was used to elaborate nanoparticles from Cu-Zn-Al alloys with shape memory effect. Two different compositions were used, target A: 75.22Cu-17.12Zn-7.66Al at % with an Ms of -9 deg C and target B: 76.18Cu-15.84Zn-7.98Al with an Ms of 20 degree C. Nanoparticles were characterized by High Resolution Transmission Electron Microscopy, Electron Diffraction and Energy Dispersive X-ray Spectroscopy. The obtained nanoparticles showed a small dispersion, with a size range of 3.2-3.5 nm. Their crystal structure is in good agreement with the bulk martensitic structure of the targets. In this sense, results on morphology, composition and crystal structure have indicated that it is possible to produce nanoparticles of CuZnAl shape memory alloys with martensitic structure in a single process using Ion Milling. (author)

  13. Nanoparticles from Cu-Zn-Al shape memory alloys physically synthesized by ion milling deposition

    International Nuclear Information System (INIS)

    Pavon, Luis Alberto Lopez; Cuellara, Enrique Lopez; Castro, Alejandro Torres; Cruza, Azael Martinez de la; Ballesteros, Carmen; Araujo, Carlos Jose de

    2012-01-01

    In this research, an ion milling equipment was used to elaborate nanoparticles from Cu-Zn-Al alloys with shape memory effect. Two different compositions were used, target A: 75.22Cu-17.12Zn-7.66Al at % with an Ms of -9 deg C and target B: 76.18Cu-15.84Zn-7.98Al with an Ms of 20 degree C. Nanoparticles were characterized by High Resolution Transmission Electron Microscopy, Electron Diffraction and Energy Dispersive X-ray Spectroscopy. The obtained nanoparticles showed a small dispersion, with a size range of 3.2-3.5 nm. Their crystal structure is in good agreement with the bulk martensitic structure of the targets. In this sense, results on morphology, composition and crystal structure have indicated that it is possible to produce nanoparticles of CuZnAl shape memory alloys with martensitic structure in a single process using Ion Milling. (author)

  14. Chemical bath deposition of CdS thin films doped with Zn and Cu

    Indian Academy of Sciences (India)

    Abstract. Zn- and Cu-doped CdS thin films were deposited onto glass substrates by the chemical bath technique. ... Cadmium sulfide; chemical bath deposition; doping; optical window. 1. ..... at low temperature (10 K), finding similar trends than.

  15. Relative Humidity Sensing Properties Of Cu2O Doped ZnO Nanocomposite

    International Nuclear Information System (INIS)

    Pandey, N. K.; Tiwari, K.; Tripathi, A.; Roy, A.; Rai, A.; Awasthi, P.

    2009-01-01

    In this paper we report application of Cu 2 O doped ZnO composite prepared by solid state reaction route as humidity sensor. Pellet samples of ZnO-Cu 2 O nanocrystalline powders with 2, 5 and 10 weight% of Cu 2 O in ZnO have been prepared. Pellets have been annealed at temperatures of 200-500 deg. C and exposed to humidity. It is observed that as relative humidity increases, resistance of the pellet decreases for the humidity from 10% to 90%. Sample with 5% of Cu 2 O doped in ZnO and annealed at 500 deg. C shows best results with sensitivity of 1.50 MΩ/%RH. In this case the hysteresis is low and the reproducibility high, making it the suitable candidate for humidity sensing.

  16. Enhanced Solar Photoelectrochemical Conversion Efficiency of ZnO:Cu Electrodes for Water-Splitting Application

    Directory of Open Access Journals (Sweden)

    Rekha Dom

    2013-01-01

    Full Text Available n-type ZnO:Cu photoanodes were fabricated by simple spray pyrolysis deposition technique. Influence of low concentration (range ~10−4–10−1% of Cu doping in hexagonal ZnO lattice on its photoelectrochemical performance has been investigated. The doped photoanodes displayed 7-time enhanced conversion efficiencies with respect to their undoped counterpart, as estimated from the photocurrents generated under simulated solar radiation. This is the highest enhancement in the solar conversion efficiency reported so far for the Cu-doped ZnO. This performance is attributed to the red shift in the band gap of the Cu-doped films and is in accordance with the incident-photon-current-conversion efficiency (IPCE measurements. Electrochemical studies reveal an n-type nature of these photoanodes. Thus, the study indicates a high potential of doped ZnO films for solar energy applications, in purview of the development of simple nanostructuring methodologies.

  17. Physical characterization of Cu{sub 2}ZnGeSe{sub 4} thin films from annealing of Cu-Zn-Ge precursor layers

    Energy Technology Data Exchange (ETDEWEB)

    Buffière, M., E-mail: buffiere@imec.be [Imec—Partner in Solliance, Leuven (Belgium); Department of Electrical Engineering (ESAT), KU Leuven, Heverlee (Belgium); ElAnzeery, H. [Imec—Partner in Solliance, Leuven (Belgium); KACST-Intel Consortium Center of Excellence in Nano-manufacturing Applications (CENA), Riyadh (Saudi Arabia); Microelectronics System Design department, Nile University, Cairo (Egypt); Oueslati, S.; Ben Messaoud, K. [Imec—Partner in Solliance, Leuven (Belgium); KACST-Intel Consortium Center of Excellence in Nano-manufacturing Applications (CENA), Riyadh (Saudi Arabia); Department of Physics, Faculty of Sciences of Tunis, El Manar (Tunisia); Brammertz, G.; Meuris, M. [Imec Division IMOMEC — Partner in Solliance, Diepenbeek (Belgium); Institute for Material Research (IMO) Hasselt University, Diepenbeek (Belgium); Poortmans, J. [Imec—Partner in Solliance, Leuven (Belgium); Department of Electrical Engineering (ESAT), KU Leuven, Heverlee (Belgium)

    2015-05-01

    Cu{sub 2}ZnGeSe{sub 4} (CZGeSe) can be considered as a potential alternative for wide band gap thin film devices. In this work, CZGeSe thin films were deposited on Mo-coated soda lime glass substrates by sequential deposition of sputtered Cu, Zn and e-beam evaporated Ge layers from elemental targets followed by annealing at high temperature using H{sub 2}Se gas. We report on the effect of the precursor stack order and composition and the impact of the annealing temperature on the physical properties of CZGeSe thin films. The optimal layer morphology was obtained when using a Mo/Cu/Zn/Ge precursor stack annealed at 460 °C. We have observed that the formation of secondary phases such as ZnSe can be prevented by tuning the initial composition of the stack, the stack order and the annealing conditions. This synthesis process allows synthesizing CZGeSe absorber with an optical band gap of 1.5 eV. - Highlights: • Cu{sub 2}ZnGeSe{sub 4} (CZGeSe) thin films were deposited using a two-step process. • CZGeSe dense layers were obtained using a Mo/Cu/Zn/Ge precursor annealed at 460 °C. • Formation of ZnSe can be avoided by tuning the composition and order of the initial stack. • P-type CZGeSe absorber with an optical band gap of 1.5 eV was obtained.

  18. Spray pyrolysis deposition of Cu-ZnO and Zn-SnO{sub 2} solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Khelfane, A.; Tarzalt, H.; Sebboua, B.; Zerrouki, H.; Kesri, N., E-mail: kesri5n@gmail.com [Faculty of Physics, University of Science and Technology of Houari Boumediene, Algiers (Algeria)

    2015-12-31

    Large-gap metal oxides, such as titanium, tin, and zinc oxides, have attracted great interest because of their remarkable potential in dye-sensitized solar cells (DSSC) and their low cost and simple preparation procedure. In this work, we investigated several Zn-SnO{sub 2} and Cu-ZnO thin films that were sprayed under different experimental conditions. We varied [Zn/[Sn] and [Cu/[Zn] ratios, calculated on atomic percent in the starting solution. We report some structural results of the films using X-ray diffraction. Optical reflection and transmission spectra investigated by an UV/VIS/NIR spectrophotometer permit the determination of optical constants. The direct band gap was deduced from the photon energy dependence of the absorption coefficient.

  19. Tracing contamination sources in soils with Cu and Zn isotopic ratios

    Energy Technology Data Exchange (ETDEWEB)

    Fekiacova, Z.; Cornu, S. [INRA, UR 1119 Géochimie des Sols et des Eaux, F-13100 Aix en Provence (France); Pichat, S. [Laboratoire de Géologie de Lyon (LGL-TPE), Ecole Normale Supérieure de Lyon, CNRS, UMR 5276, 69007 Lyon (France)

    2015-06-01

    Copper (Cu) and zinc (Zn) are naturally present and ubiquitous in soils and are important micronutrients. Human activities contribute to the input of these metals to soils in different chemical forms, which can sometimes reach a toxic level for soil organisms and plants. Isotopic signatures could be used to trace sources of anthropogenic Cu and Zn pollution. The aim of this paper is to determine whether it is possible to identify (i) Cu and Zn contamination in soils and their sources, on the basis of their isotopic signatures, and (ii) situations that are a priori favorable or not for tracing Cu and Zn pollution using the isotopic approach. Therefore, we compiled data from the literature on Cu and Zn isotopes in soils, rocks and pollutants and added to this database the results of our own research. As only a few studies have dealt with agricultural contamination, we also studied a soil toposequence from Brittany, France, that experienced spreading of pig slurry for tens of years. In the surface horizons of the natural soils, the δ{sup 65}Cu values vary from − 0.15 to 0.44‰ and the δ{sup 66}Zn from − 0.03 to 0.43‰. Furthermore, vertical variations along soil profiles range from − 0.95 to 0.44‰ for δ{sup 65}Cu and from − 0.53 to 0.64‰ for δ{sup 66}Zn values. We concluded that pedogenetic processes can produce isotopic fractionation, yet, it is not always discernible and can be overprinted by an exogenous isotopic signature. Furthermore, some contaminants are enriched in heavy Cu or in light Zn compared to the rock or soil, but no generalization can be made. The anthropogenic inputs can be identified based on stable Cu and Zn isotope ratios if the isotope ratios of the sources are different from those of the soil, which needs to be tested for each individual case. - Highlights: • Pedogenetic processes produce some Cu and Zn isotope fractionation. • Pollution with distinct isotopic signatures can be traced using Cu and Zn isotopes. • Tracing

  20. Tracing contamination sources in soils with Cu and Zn isotopic ratios

    International Nuclear Information System (INIS)

    Fekiacova, Z.; Cornu, S.; Pichat, S.

    2015-01-01

    Copper (Cu) and zinc (Zn) are naturally present and ubiquitous in soils and are important micronutrients. Human activities contribute to the input of these metals to soils in different chemical forms, which can sometimes reach a toxic level for soil organisms and plants. Isotopic signatures could be used to trace sources of anthropogenic Cu and Zn pollution. The aim of this paper is to determine whether it is possible to identify (i) Cu and Zn contamination in soils and their sources, on the basis of their isotopic signatures, and (ii) situations that are a priori favorable or not for tracing Cu and Zn pollution using the isotopic approach. Therefore, we compiled data from the literature on Cu and Zn isotopes in soils, rocks and pollutants and added to this database the results of our own research. As only a few studies have dealt with agricultural contamination, we also studied a soil toposequence from Brittany, France, that experienced spreading of pig slurry for tens of years. In the surface horizons of the natural soils, the δ 65 Cu values vary from − 0.15 to 0.44‰ and the δ 66 Zn from − 0.03 to 0.43‰. Furthermore, vertical variations along soil profiles range from − 0.95 to 0.44‰ for δ 65 Cu and from − 0.53 to 0.64‰ for δ 66 Zn values. We concluded that pedogenetic processes can produce isotopic fractionation, yet, it is not always discernible and can be overprinted by an exogenous isotopic signature. Furthermore, some contaminants are enriched in heavy Cu or in light Zn compared to the rock or soil, but no generalization can be made. The anthropogenic inputs can be identified based on stable Cu and Zn isotope ratios if the isotope ratios of the sources are different from those of the soil, which needs to be tested for each individual case. - Highlights: • Pedogenetic processes produce some Cu and Zn isotope fractionation. • Pollution with distinct isotopic signatures can be traced using Cu and Zn isotopes. • Tracing of the metal

  1. Cu-implanted ZnO nanorods array film: An aqueous synthetic approach

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Ajaya Kumar, E-mail: ajayaksingh_au@yahoo.co.in [Department of Chemistry, Govt. VYT PG. Autonomous College Durg, Chhattisgarh (India); Thool, Gautam Sheel [Department of Chemistry, Govt. VYT PG. Autonomous College Durg, Chhattisgarh (India); Singh, R.S. [Department of Physics, Govt. D.T. College, Utai, Durg, Chhattisgarh (India); Singh, Surya Prakash, E-mail: spsingh@iict.res.in [Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal road, Tarnaka, Hyderabad 500007 (India)

    2015-01-05

    Highlights: • Cu doped ZnO nanorods were synthesized using low temperature aqueous solution method. • We demonstrated the capping action of TEA via theoretical simulation. • Raman analysis revealed the presence of tensile strain in Cu doped ZnO nanorods. • Growth rate was found to be high in Cu doped ZnO nanorods. - Abstract: Pure and Cu doped ZnO nanorods array are synthesized via two step chemical bath deposition method. The seed layer is prepared by successive ionic layer adsorption reaction (SILAR) method. The synthesized materials have been systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDAX), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and photoluminescence (PL) spectroscopy. SEM pictures show the existence of vertically well aligned hexagonal ZnO nanorods. EDAX spectrum confirms the presence of Cu in ZnO nanorods. High intense peak of (0 0 2) plane and E{sub 2}{sup high} mode for XRD and Raman spectrum respectively, suggest the ZnO nanorods are adopted c-axis orientation perpendicular to substrate. XRD and Raman analysis shows the presence of tensile strain in Cu doped ZnO nanorods. Effect of Cu doping on lattice constants, unit cell volume and Zn–O bond length of ZnO nanorods have also been studied. Room temperature PL measurement exhibits two luminescence bands in the spectra i.e. UV emission centered at 3.215 eV and a broad visible band. Theoretical investigation for capping action of triethanolamine is done by Hartree–Fock (HF) method with 3-21G basis set using Gaussian 09 program package.

  2. Inkjet?Printed Cu2ZnSn(S, Se)4 Solar Cells

    OpenAIRE

    Lin, Xianzhong; Kavalakkatt, Jaison; Lux?Steiner, Martha Ch.; Ennaoui, Ahmed

    2015-01-01

    Cu2ZnSn(S, Se)4?based solar cells with total area (0.5 cm2) power conversion efficiency of 6.4% are demonstrated from thin film absorbers processed by inkjet printing technology of Cu?Zn?Sn?S precursor ink followed by selenization. The device performance is limited by the low fill factor, which is due to the high series resistance.

  3. Inkjet-Printed Cu2ZnSn(S, Se)4 Solar Cells.

    Science.gov (United States)

    Lin, Xianzhong; Kavalakkatt, Jaison; Lux-Steiner, Martha Ch; Ennaoui, Ahmed

    2015-06-01

    Cu 2 ZnSn(S, Se) 4 -based solar cells with total area (0.5 cm 2 ) power conversion efficiency of 6.4% are demonstrated from thin film absorbers processed by inkjet printing technology of Cu-Zn-Sn-S precursor ink followed by selenization. The device performance is limited by the low fill factor, which is due to the high series resistance.

  4. A Question of Balance: Facing the challenges of Cu, Fe and Zn Homeostasis

    OpenAIRE

    Palmer, Christine; Guerinot, Mary Lou

    2009-01-01

    Plants have recently moved into the spotlight with the growing realization that the world needs solutions to energy and food production that are sustainable and environmentally sound. Iron (Fe), copper (Cu), and zinc (Zn) are essential for plant growth and development, yet the same properties that make these transition metals indispensable can also make them deadly in excess. Fe and Cu are most often utilized for their redox properties, while Zn is primarily utilized for is ability to act as ...

  5. Adsorption of Pb, Cd, Zn, Cu and Hg ions on Formaldehyde and ...

    African Journals Online (AJOL)

    Adsorption of Pb(II), Cd(II), Zn(II), Cu(II) and Hg(II) ions on formaldehyde and Pyridine modified bean husks were determined. The adsorption capacity of formaldehyde modified bean husks (mg/g) was: Pb2+, 5.01; Cd2+, 3.63; Zn2+, 2.18; Hg2+, 1.82; Cu2+, 1.58 and that of pyridine modified bean husk was: Hg2+, 6.92; Cd2+ ...

  6. Construction and evaluation of multi-component Zn-Al based bearing alloys (Zn-Al-Si, Zn-Al-Cu)

    International Nuclear Information System (INIS)

    Shahmiri, M.; Shahin, K.

    2001-01-01

    Zn-Al based alloys, with excellent mechanical properties, are finding increasing applications in various industries, especially bearing and bushing fields. Observed dimensional instabilities, in their multicomponent systems, (e. g. Zn-Al-Si and, Zn-Al Si-Cu), is believed to be as the result of some kinds of phase transformation, due to the temperature variations, while in service. Profound understanding of the phase transformations due to the temperature variation, requires detailed evaluations of the isothermal sections of the multi-components phase diagrams of Zn-Al-Si and, Zn-Al-Si-Cu alloy systems. In the present article, the isothermal sections of the aforementioned ternary and quaternary systems in the solid state regions have been investigated and observed phase transitions have been critically evaluated

  7. Abnormal room temperature ferromagnetism in CuO/ZnO nanocomposites via hydrothermal method

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ping; Zhou, Wei; Li, Ying; Wang, Jianchun; Wu, Ping, E-mail: pingwu@tju.edu.cn

    2017-03-31

    Highlights: • CuO/ZnO nanocomposites have been synthesized by a one-step hydrothermal method. • The interaction between ZnO and CuO causes a modification of electronic structure. • The abnormal RTFM is discovered at the interface of CuO/ZnO. • The M{sub S} can be tuned by changing the phase ratios of the CuO and ZnO. • The indirect double-exchange model was employed to explain the origin of magnetism. - Abstract: CuO/ZnO nanocomposites have been successfully synthesized by a one-step hydrothermal method with different phase ratios. Field emission scanning electron microscopy and transmission electron microscopy results show that the obtained products of nanosheets are composed of small primary particles with an average size of about 20 nm. With the increasing proportion of CuO phase, nanosheets have significant collapse and the amount of small sheets increases obviously. The abnormal room temperature ferromagnetism was discovered at the interface between diamagnetic ZnO and antiferromagnetic CuO, which can be tuned by changing the phase ratios. Optical spectra indicate that the interaction between ZnO and CuO modifies the electronic structure of nanocomposites. XPS results verify the valence change of Cu ions and the presence of oxygen vacancies, which are ultimately responsible for the observed ferromagnetism. The indirect double-exchange model was employed to explain the origin of magnetism. Our study suggests that magnetically functional interfaces exhibit very appealing properties for novel devices.

  8. One-pot synthesis of Cu/ZnO/ZnAl2O4 catalysts and their catalytic performance in glycerol hydrogenolysis

    KAUST Repository

    Tan, Hua

    2013-01-01

    In this work, a series of Cu/ZnO/ZnAl2O4 catalysts with different metal molar fractions (Cu:Zn:Al) were successfully prepared using a one-pot method via the evaporation-induced self-assembly (EISA) of Pluronic P123 and the corresponding metal precursors. The catalysts were characterized using N2 adsorption, H2 temperature-programmed reduction (H2-TPR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectra (XPS). The catalytic properties of the resulting Cu/ZnO/ZnAl2O4 with different molar fractions of metals were investigated for the selective hydrogenolysis of glycerol to 1,2-propanediol (1,2-PDO). It was observed that the ZnAl2O 4 support exerts a strong positive effect on the catalytic activity of the copper-based catalysts, and the presence of ZnO further improves the catalytic activity of the Cu/ZnAl2O4 catalysts. The Cu/ZnO/ZnAl2O4 catalyst (Cu10Zn 30Al60, Cu/Zn/Al molar ratio is 10:30:60), which was the best catalyst, exhibited the highest yield (79%) of 1,2-PDO with 85.8% glycerol conversion and 92.1% 1,2-PDO selectivity at 180 °C reaction temperature in 80 wt% glycerol aqueous solution over 10 h reaction time. The high catalytic activity was attributed to the presence of the ZnAl2O4 support, the strong interaction between ZnO and Cu nanoparticles and the small particle size of ZnO and Cu. Moreover, the Cu/ZnO/ZnAl2O4 catalysts exhibited higher stability than Cu/ZnO and Cu/ZnO/Al2O 3 catalysts prepared by a co-precipitation method during consecutive cycling experiments, which is due to the high chemical and thermal stability of crystalline ZnAl2O4 under harsh reaction conditions. This journal is © The Royal Society of Chemistry.

  9. Synthesis and description of complexes of Cu(I), Mn(II) and Zn(II) using the linking N,N'-bis(2-sulphide benzil)-3,3'-diamine N'-methyldipropylamine of sodium

    International Nuclear Information System (INIS)

    Amador Godoy, Ginnette

    2000-01-01

    This work optimized the synthesis's procedure of the linking called N,N ' -bis(2-sulphide benzil)-3,3 ' -diamino - N ' -methyldipropylamine of sodium. It described the synthesis's intermediate products of the linking by 1 H-NMR. It synthesized complexes utilizing the linking mentioned previously and the metal salts of cooper and manganese. The description of the complexes was realized by electrochemical, magnetic and spectroscopic methods. To the (I) cooper's complex, it was gotten an effective magnetic moment of 0.62 M.B. and the molecular formula proposed is: C 2 1H 2 9N 3 S 2 Cu.CH 3 OH. It determined that the oxide-reduction process is quasi reversible. The (II) manganese's complex has an effective magnetic moment of 5.2 M.B. that corresponds to a configuration d 5 of tall porcupine. It proposes the molecular formula C 2 1H 2 9N 3 S 2 Mn and the metal/nitrogen relation is 3/1. The oxide-reduction process is quasi reversible. It described the zinc's complex in dissolution by 1 H-NMR and 1 3C-NMR to different temperatures, it observed an increase of the separation and definition of the signals when the temperature increased until to get an spectro 1 H-NMR to 130 centigrade with the standard signals of the different shapes that can adopt the molecule, besides it got an spectro of 1 3C-NMR to 100 centigrade [es

  10. Dielectric properties investigation of Cu2O/ZnO heterojunction thin films by electrodeposition

    International Nuclear Information System (INIS)

    Li, Qiang; Xu, Mengmeng; Fan, Huiqing; Wang, Hairong; Peng, Biaolin; Long, Changbai; Zhai, Yuchun

    2013-01-01

    Highlights: ► Bottom-up self-assembly Cu 2 O/ZnO heterojunction was fabricated by electrochemical deposition on indium tin oxide (ITO) flexible substrate (polyethylene terephthalate-PET). ► The dielectric response of Cu 2 O/ZnO heterojunction thin films had been investigated. ► The universal dielectric response was used to investigate the hopping behavior in Cu 2 O/ZnO heterojunction. -- Abstract: Structures and morphologies of the Cu 2 O/ZnO heterojunction electrodeposited on indium tin oxide (ITO) flexible substrate (polyethylene terephthalate-PET) were investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM), high resolution transmission electron microscopy (HRTEM), respectively. The dielectric response of bottom-up self-assembly Cu 2 O/ZnO heterojunction was investigated. The low frequency dielectric dispersion (LFDD) was observed. The universal dielectric response (UDR) was used to investigate the frequency dependence of dielectric response for Cu 2 O/ZnO heterojunction, which was attributed to the long range and the short range hopping charge carriers at the low frequency and the high frequency region, respectively

  11. Modification and inactivation of Cu,Zn-superoxide dismutase by the lipid peroxidation product, acrolein

    Directory of Open Access Journals (Sweden)

    Jung Hoon Kang

    2013-11-01

    Full Text Available Acrolein is the most reactive aldehydic product of lipidperoxidation and is found to be elevated in the brain whenoxidative stress is high. The effects of acrolein on the structureand function of human Cu,Zn-superoxide dismutase (SOD wereexamined. When Cu,Zn-SOD was incubated with acrolein, thecovalent crosslinking of the protein was increased, and the loss ofenzymatic activity was increased in a dose-dependent manner.Reactive oxygen species (ROS scavengers and copper chelatorsinhibited the acrolein-mediated Cu,Zn-SOD modification and theformation of carbonyl compound. The present study shows thatROS may play a critical role in acrolein-induced Cu,Zn-SODmodification and inactivation. When Cu,Zn-SOD that has beenexposed to acrolein was subsequently analyzed by amino acidanalysis, serine, histidine, arginine, threonine and lysine residueswere particularly sensitive. It is suggested that the modificationand inactivation of Cu,Zn-SOD by acrolein could be produced bymore oxidative cell environments. [BMB Reports 2013; 46(11:555-560

  12. Comparison of Cu2+ and Zn2+ thermalcatalyst in treating diazo dye

    Science.gov (United States)

    Lau, Y. Y.; Wong, Y. S.; Ong, S. A.; Lutpi, N. A.; Ho, L. N.

    2018-05-01

    This research demonstrates the comparison between copper (II) sulphate (CuSO4) and zinc oxide (ZnO) as thermalcatalysts in thermolysis process for the treatment of diazo reactive black 5 (RB 5) wastewater. CuSO4 was found to be the most effective thermalcatalyst in comparison to ZnO. The color removal efficiency of RB 5 catalysed by CuSO4 and ZnO were 91.55 % at pH 9.5 and 7.36 % at pH 2, respectively. From the UV-Vis wavelength scan, CuSO4 catalyst is able to cleave the molecular structure bonding more efficiently compared to ZnO. ZnO which only show a slight decay on the main chemical network strands: azo bond, naphthalene and benzene rings whereas CuSO4 catalyst is able to fragment azo bond and naphthalene more effectively. The degradation reactions of CuSO4 and ZnO as thermalcatalysts in thermolysis process were compared.

  13. Mesoporous CuO–ZnO binary metal oxide nanocomposite for decontamination of sulfur mustard

    International Nuclear Information System (INIS)

    Praveen Kumar, J.; Prasad, G.K.; Ramacharyulu, P.V.R.K.; Garg, P.; Ganesan, K.

    2013-01-01

    Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. They were prepared by precipitation pyrolysis method and characterized by means of X-ray diffraction, transmission electron microscopy, nitrogen adsorption, Fourier transform infrared spectroscopy techniques. Obtained data indicated the presence of mesopores with diameter ranging from 2 to 80 nm and the materials exhibited relatively high surface area 86 m 2 g −1 when compared to the individual metal oxide nanoparticles. Reactive sites of mesoporous CuO–ZnO binary metal oxide nanocomposites were studied by infrared spectroscopy technique using pyridine as a probe molecule. These materials demonstrated superior decontamination properties against sulfur mustard when compared to single component metal oxides and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Graphical abstract: Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. These materials demonstrated superior decontamination properties against sulfur mustard and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Highlights: • Preparation of mesoporous CuO–ZnO binary metal oxide nanocomposite. • CuO–ZnO with better surface area was synthesized by precipitation pyrolysis. • Decontamination of HD using mesoporous CuO–ZnO binary metal oxide nanocomposite. • HD decontaminated by elimination and hydrolysis reactions

  14. Mesoporous CuO–ZnO binary metal oxide nanocomposite for decontamination of sulfur mustard

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, J.; Prasad, G.K., E-mail: gkprasad2001@yahoo.com; Ramacharyulu, P.V.R.K.; Garg, P.; Ganesan, K.

    2013-11-01

    Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. They were prepared by precipitation pyrolysis method and characterized by means of X-ray diffraction, transmission electron microscopy, nitrogen adsorption, Fourier transform infrared spectroscopy techniques. Obtained data indicated the presence of mesopores with diameter ranging from 2 to 80 nm and the materials exhibited relatively high surface area 86 m{sup 2} g{sup −1} when compared to the individual metal oxide nanoparticles. Reactive sites of mesoporous CuO–ZnO binary metal oxide nanocomposites were studied by infrared spectroscopy technique using pyridine as a probe molecule. These materials demonstrated superior decontamination properties against sulfur mustard when compared to single component metal oxides and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Graphical abstract: Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. These materials demonstrated superior decontamination properties against sulfur mustard and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Highlights: • Preparation of mesoporous CuO–ZnO binary metal oxide nanocomposite. • CuO–ZnO with better surface area was synthesized by precipitation pyrolysis. • Decontamination of HD using mesoporous CuO–ZnO binary metal oxide nanocomposite. • HD decontaminated by elimination and hydrolysis reactions.

  15. Migration behavior of Cu and Zn in landfill with different operation modes

    International Nuclear Information System (INIS)

    Long Yuyang; Shen Dongsheng; Wang Hongtao; Lu Wenjing

    2010-01-01

    Cu and Zn were chosen to study the heavy metal migration behavior and mechanism in three simulated landfills with different operation modes, namely conventional landfill (CL), leachate directly recirculated landfill (RL) and leachate pre-treated bioreactor landfill (BL). It showed that Cu and Zn in refuse experienced periodic migration and retention gradually during decomposition, and the variation of Cu(II) and Zn(II) in leachate correspondingly reflected the releasing behavior of Cu and Zn in landfill refuse at different stabilization stages. Except for their accumulated leaching amounts, Cu(II) and Zn(II) concentrations in leachate from landfills with different operation modes had no significant difference. The accumulated leaching amounts of Cu and Zn from CL showed exponential increase, while those of RL and BL showed exponential decay. The operation of bioreactor landfill with leachate recirculation can obviously attenuate the heavy metal leaching than conventional operation. The introduction of methanogenic reactor (MR) in bioreactor landfill can further promote the immobilization of heavy metal in refuse than leachate recirculation directly.

  16. Phytoremediation of Sb, As, Cu, and Zn from contaminated water by the aquatic macrophyte eleocharis acicularis

    Energy Technology Data Exchange (ETDEWEB)

    Sakakibara, Masayuki [Graduate School of Science and Engineering, Ehime University, Ehime (Japan); Sano, Sakae [Faculty of Education, Ehime University, Ehime (Japan); Ha, Nguyen Thi Hoang

    2009-09-15

    Sb, As, Cu, and Zn toxicity and contamination have become a growing concern in recent years. Phytoremediation, a plant based and cost effective technology, may be an effective approach in the cleanup of water contaminated by these metals. In this study, the aquatic macrophyte Eleocharis acicularis was used in laboratory and field experiments to assess its capability to accumulate Sb, As, Cu, and Zn, and thereby investigate its potential application in phytoremediation. The results showed that E. acicularis adapted well to water contaminated by these metals. The removal rates of Sb, As, Cu, and Zn in the laboratory experiment were 3.04, 2.75, 0.417, and 1.49 {mu}g/L/day, respectively. The highest concentrations of these metals accumulated in E. acicularis after 10 days of the laboratory experiment were 6.29, 6.44, 20.5, and 73.5 mg/kg dry weight, respectively. Only 8% of As, 12% of Sb, 87% of Cu and 93% of Zn removed from the water were used by E. acicularis. The highest concentrations of Sb, As, Cu, and Zn accumulated in E. acicularis after 10 wk of the field experiment were 76.0, 22.4, 33.9, and 266 mg/kg dry weight, respectively. The results indicate that E. acicularis has the ability to accumulate Sb, As, Cu, and Zn from contaminated water. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  17. Percolation-induced plasmonic state and double negative electromagnetic properties of Ni-Zn Ferrite/Cu granular composite materials

    Science.gov (United States)

    Massango, Herieta; Kono, Koji; Tsutaoka, Takanori; Kasagi, Teruhiro; Yamamoto, Shinichiro; Hatakeyama, Kenichi

    2018-05-01

    Complex permeability and permittivity spectra of Ni-Zn Ferrite/Cu hybrid granular composite materials have been studied in the RF to microwave frequency range. The electrical conductivity σ shows insulating properties in the volume fraction of Cu particles below φ = 0.14. A large jump in conductivity was observed between φ = 0.14 and 0.24 indicating that the Cu particles make metallic conduction between this interval. Hence, the percolation threshold φC, was estimated to be 0.14. A percolation-induced low frequency plasmonic state with negative permittivity spectrum was observed from φ = 0.14-0.24. Meanwhile the negative permeability was observed at φ = 0.16, 0.19 and 0.24. Hence the DNG characteristic was realized in these Cu volume content in the frequency range from 105 MHz to 2 GHz.

  18. Spectroscopic ellipsometry study of Cu2ZnSnSe4 bulk crystals

    International Nuclear Information System (INIS)

    León, M.; Lopez, N.; Merino, J. M.; Caballero, R.; Levcenko, S.; Gurieva, G.; Serna, R.; Bodnar, I. V.; Nateprov, A.; Guc, M.; Arushanov, E.; Schorr, S.; Perez-Rodriguez, A.

    2014-01-01

    Using spectroscopic ellipsometry we investigated and analyzed the pseudo-optical constants of Cu 2 ZnSnSe 4 bulk crystals, grown by the Bridgman method, over 0.8–4.5 eV photon energy range. The structures found in the spectra of the complex pseudodielectric functions were associated to E 0 , E 1A , and E 1B interband transitions and were analyzed in frame of the Adachi's model. The interband transition parameters such as strength, threshold energy, and broadening were evaluated by using the simulated annealing algorithm. In addition, the pseudo-complex refractive index, extinction coefficient, absorption coefficient, and normal-incidence reflectivity were derived over 0.8–4.5 eV photon energy range

  19. Spectroscopic ellipsometry study of Cu{sub 2}ZnSnSe{sub 4} bulk crystals

    Energy Technology Data Exchange (ETDEWEB)

    León, M., E-mail: maximo.leon@uam.es; Lopez, N.; Merino, J. M.; Caballero, R. [Department of Applied Physics M12, Universidad Autónoma de Madrid, Madrid (Spain); Levcenko, S.; Gurieva, G. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Serna, R. [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain); Bodnar, I. V. [Department of Chemistry, Belarusian State University of Informatics and Radioelectronics, Minsk (Belarus); Nateprov, A.; Guc, M.; Arushanov, E. [Institute of Applied Physics, Academy of Sciences of Moldova, Chisinau MD 2028 (Moldova, Republic of); Schorr, S. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Institute of Geological Sciences, Free University Berlin, Malteserstr. 74-100, Berlin (Germany); Perez-Rodriguez, A. [IREC, Catalonia Institute for Energy Research, C. Jardins de les Dones de Negre 1, 08930 Sant Adrià del Besòs (Barcelona) (Spain); IN2UB, Departament d' Electrònica, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain)

    2014-08-11

    Using spectroscopic ellipsometry we investigated and analyzed the pseudo-optical constants of Cu{sub 2}ZnSnSe{sub 4} bulk crystals, grown by the Bridgman method, over 0.8–4.5 eV photon energy range. The structures found in the spectra of the complex pseudodielectric functions were associated to E{sub 0}, E{sub 1A}, and E{sub 1B} interband transitions and were analyzed in frame of the Adachi's model. The interband transition parameters such as strength, threshold energy, and broadening were evaluated by using the simulated annealing algorithm. In addition, the pseudo-complex refractive index, extinction coefficient, absorption coefficient, and normal-incidence reflectivity were derived over 0.8–4.5 eV photon energy range.

  20. Effects of Cu content on the photoelectrochemistry of Cu2ZnSnS4 nanocrystal thin films

    International Nuclear Information System (INIS)

    Khoshmashrab, Saghar; Turnbull, Matthew J.; Vaccarello, Daniel; Nie, Yuting; Martin, Spencer; Love, David A.; Lau, Po K.; Sun, Xuhui; Ding, Zhifeng

    2015-01-01

    Highlights: • Two compositions of CZTS were synthesized, one yielding Cu-poor and the other Cu-stoichiometric nanocrystals (NCs). • Physical and electronic properties of both films were probed using various analytical techniques. • Films comprised of Cu-poor CZTS showed tighter packing with less defects compared to those of stoichiometric-Cu. • Photoelectrochemical measurements exhibited increased photoconversion and increased photostability of the Cu-poor films. • Intensity modulated photocurrent spectroscopy showed that the Cu-deficient NCs had half the recombination rate as that of stoichiometric-Cu films. - Abstract: Cu 2 ZnSnS 4 (CZTS) nanocrystals (NCs) were prepared via a one-pot solvothermal method. Given that the composition affects the electronic properties of this p-type semiconductor, two compositional ratios were chosen from 10 designed and synthesized analogues, one yielding Cu-poor and the other Cu-stoichiometric CZTS. NCs in which the Cu concentration was slightly below stoichiometric yielded more uniform films with greater photovoltaic performance. The lower Cu content also lead to slightly better crystallinity within the film, as demonstrated by XRD, Raman spectroscopy and transmission electron microscopy. Chronophotoelectrochemical measurements indicated that both types of NC films displayed good stability; however, with a decrease in potential, an increase in resistance for the Cu-stoichiometric film was observed. As determined by intensity modulated photocurrent spectroscopy, the product separation rate of the photoinduced holes and electrons in the Cu-poor films were more than 3 times that of the Cu-stoichiometric, confirming that the lower Cu content led to an improved photoperformance

  1. Cu,Zn superoxide dismutase: cloning and analysis of the Taenia solium gene and Taenia crassiceps cDNA.

    Science.gov (United States)

    Parra-Unda, Ricardo; Vaca-Paniagua, Felipe; Jiménez, Lucia; Landa, Abraham

    2012-01-01

    Cytosolic Cu,Zn superoxide dismutase (Cu,Zn-SOD) catalyzes the dismutation of superoxide (O(2)(-)) to oxygen and hydrogen peroxide (H(2)O(2)) and plays an important role in the establishment and survival of helminthes in their hosts. In this work, we describe the Taenia solium Cu,Zn-SOD gene (TsCu,Zn-SOD) and a Taenia crassiceps (TcCu,Zn-SOD) cDNA. TsCu,Zn-SOD gene that spans 2.841 kb, and has three exons and two introns; the splicing junctions follow the GT-AG rule. Analysis in silico of the gene revealed that the 5'-flanking region has three putative TATA and CCAAT boxes, and transcription factor binding sites for NF1 and AP1. The transcription start site was a C, located at 22 nucleotides upstream of the translation start codon (ATG). Southern blot analysis showed that TcCu,Zn-SOD and TsCu,Zn-SOD genes are encoded by a single copy. The deduced amino acid sequences of TsCu,Zn-SOD gene and TcCu,Zn-SOD cDNA reveal 98.47% of identity, and the characteristic motives, including the catalytic site and β-barrel structure of the Cu,Zn-SOD. Proteomic and immunohistochemical analysis indicated that Cu,Zn-SOD does not have isoforms, is distributed throughout the bladder wall and is concentrated in the tegument of T. solium and T. crassiceps cysticerci. Expression analysis revealed that TcCu,Zn-SOD mRNA and protein expression levels do not change in cysticerci, even upon exposure to O(2)(-) (0-3.8 nmol/min) and H(2)O(2) (0-2mM), suggesting that this gene is constitutively expressed in these parasites. Published by Elsevier Inc.

  2. Facile synthesis of Zn doped CuO hierarchical nanostructures: Structural, optical and antibacterial properties

    Directory of Open Access Journals (Sweden)

    Javed Iqbal

    2015-12-01

    Full Text Available ZnxCu1−xO (where x= 0, 0.01, 0.03, 0.05, 0.07 and 0.1 mol% hierarchical nanostructures have been prepared via soft chemical route. X-ray diffraction (XRD results of the synthesized samples reveal the monoclinic structure of CuO without any impurity related phases. The micro-structural parameters such as crystallite size and microstrain have been strongly influenced by Zn doping. Scanning electron microscope (SEM analyses depict the formation of hierarchical nanostructures having average particle size in the range of 26-43 nm. The surface area of CuO nanostructures has been reduced systematically with the increase in Zn content which is linked with the variations in particle size. An obvious decrease in the optical band gap energy of the synthesized CuO hierarchical nanostructures has been observed with Zn doping which is assigned to the formation of shallow levels in the band gap of CuO and combined transition from oxygen 2p states to d sates of Cu and Zn ions. The bactericidal potency of the CuO hierarchical nanostructures have been found to be enhanced remarkably with Zn doping.

  3. Re-partitioning of Cu and Zn isotopes by modified protein expression

    Directory of Open Access Journals (Sweden)

    Ragnarsdottir K Vala

    2008-10-01

    Full Text Available Abstract Cu and Zn have naturally occurring non radioactive isotopes, and their isotopic systematics in a biological context are poorly understood. In this study we used double focussing mass spectroscopy to determine the ratios for these isotopes for the first time in mouse brain. The Cu and Zn isotope ratios for four strains of wild-type mice showed no significant difference (δ65Cu -0.12 to -0.78 permil; δ66Zn -0.23 to -0.48 permil. We also looked at how altering the expression of a single copper binding protein, the prion protein (PrP, alters the isotope ratios. Both knockout and overexpression of PrP had no significant effect on the ratio of Cu isotopes. Mice brains expressing mutant PrP lacking the known metal binding domain have δ65Cu isotope values of on average 0.57 permil higher than wild-type mouse brains. This implies that loss of the copper binding domain of PrP increases the level of 65Cu in the brain. δ66Zn isotope values of the transgenic mouse brains are enriched for 66Zn to the wild-type mouse brains. Here we show for the first time that the expression of a single protein can alter the partitioning of metal isotopes in mouse brains. The results imply that the expression of the prion protein can alter cellular Cu isotope content.

  4. Effects of Cu, Zn and Pb Combined Pollution on Soil Hydrolase Activities

    Directory of Open Access Journals (Sweden)

    FENG Dan

    2015-08-01

    Full Text Available To study the relations between soil enzyme activities and heavy metal pollution, the combined effects of Cu, Zn and Pb on the three hydrolase activities, including invertase(IN, urease(Uand alkaline phosphatase(ALPwere investigated via an orthogonal experiment. Results showed as the following: When the concentration of Cu was 400 mg·kg-1, the U and ALP activities were decreased 51% and 44%, separately; When Zn was at 500 mg·kg-1, IN and ALP activities were only decreased 3% and 9%, while U activity was increased; When Pb was at 500 mg·kg-1, IN and U activities were increased, while ALP activity was decreased 13%. As a whole, Cu was considered as the most remarkable influence factor for IN, U and ALP activity regardless of interactions among the heavy metals, Zn came second, and Pb mainly showed activation. Considering interactions, Cu×Zn could significantly influence U activity(P<0.05, effects of Cu×Pb and Cu×Zn on ALP activity were remarkable(95% confidence interval. The response of ALP activity was more sensitive than the other two enzymes. Soil ALP activity might be a sensitive tool for assessing the pollution degree of Cu.

  5. The crystallisation of Cu{sub 2}ZnSnS{sub 4} thin film solar cell absorbers from co-electroplated Cu-Zn-Sn precursors

    Energy Technology Data Exchange (ETDEWEB)

    Schurr, R. [Chair for Crystallography and Structural Physics, University of Erlangen-Nuernberg, Staudtstrasse 3, D-91058 Erlangen (Germany)], E-mail: schurr@krist.uni-erlangen.de; Hoelzing, A.; Jost, S.; Hock, R. [Chair for Crystallography and Structural Physics, University of Erlangen-Nuernberg, Staudtstrasse 3, D-91058 Erlangen (Germany); Voss, T.; Schulze, J.; Kirbs, A. [Atotech Deutschland GmbH, Erasmusstrasse 20, D-10553 Berlin (Germany); Ennaoui, A.; Lux-Steiner, M. [Heterogeneous Material Systems SE II, Hahn-Meitner-Institut, Glienickerstr.100, D-14109 Berlin (Germany); Weber, A.; Koetschau, I.; Schock, H.-W. [Technology SE III, Hahn-Meitner-Institut, Glienickerstr.100, D-14109 Berlin (Germany)

    2009-02-02

    The best CZTS solar cell so far was produced by co-sputtering continued with vapour phase sulfurization method. Efficiencies of up to 5.74% were reached by Katagiri et al. The one step electrochemical deposition of copper, zinc, tin and subsequent sulfurization is an alternative fabrication technique for the production of Cu{sub 2}ZnSnS{sub 4} based thin film solar cells. A kesterite based solar cell (size 0.5 cm{sup 2}) with a conversion efficiency of 3.4% (AM1.5) was produced by vapour phase sulfurization of co-electroplated Cu-Zn-Sn films. We report on results of in-situ X-ray diffraction (XRD) experiments during crystallisation of kesterite thin films from electrochemically co-deposited metal films. The kesterite crystallisation is completed by the solid state reaction of Cu{sub 2}SnS{sub 3} and ZnS. The measurements show two different reaction paths depending on the metal ratios in the as deposited films. In copper-rich metal films Cu{sub 3}Sn and CuZn were found after electrodeposition. In copper-poor or near stoichiometric precursors additional Cu{sub 6}Sn{sub 5} and Sn phases were detected. The formation mechanism of Cu{sub 2}SnS{sub 3} involves the binary sulphides Cu{sub 2-x}S and SnS{sub 2} in the absence of the binary precursor phase Cu{sub 6}Sn{sub 5}. The presence of Cu{sub 6}Sn{sub 5} leads to a preferred formation of Cu{sub 2}SnS{sub 3} via the reaction educts Cu{sub 2-x}S and SnS{sub 2} in the presence of a SnS{sub 2}(Cu{sub 4}SnS{sub 6}) melt. The melt phase may be advantageous in crystallising the kesterite, leading to enhanced grain growth in the presence of a liquid phase.

  6. Chelation of Cu(II, Zn(II, and Fe(II by Tannin Constituents of Selected Edible Nuts

    Directory of Open Access Journals (Sweden)

    Magdalena Karamać

    2009-12-01

    Full Text Available The tannin fractions isolated from hazelnuts, walnuts and almonds were characterised by colorimetric assays and by an SE-HPLC technique. The complexation of Cu(II and Zn(II was determined by the reaction with tetramethylmurexide, whereas for Fe(II, ferrozine was employed. The walnut tannins exhibited a significantly weaker reaction with the vanillin/HCl reagent than hazelnut and almond tannins, but the protein precipitation capacity of the walnut fraction was high. The SE-HPLC chromatogram of the tannin fraction from hazelnuts revealed the presence of oligomers with higher molecular weights compared to that of almonds. Copper ions were most effectively chelated by the constituents of the tannin fractions of hazelnuts, walnuts and almonds. At a 0.2 mg/assay addition level, the walnut tannins complexed almost 100% Cu(II. The Fe(II complexation capacities of the tannin fractions of walnuts and hazelnuts were weaker in comparison to that of the almond tannin fraction, which at a 2.5 mg/assay addition level, bound Fe(II by ~90%. The capacity to chelate Zn(II was quite varied for the different nut tannin fractions: almond tannins bound as much as 84% Zn(II, whereas the value for walnut tannins was only 8.7%; and for hazelnut tannins, no Zn(II chelation took place at the levels tested.

  7. Elimination of Cu (II) and Zn (II) ions in mono-element and the bi ...

    African Journals Online (AJOL)

    Elimination of Cu (II) and Zn (II) ions in mono-element and the bi-element aqueous solutions by adsorption on natural clay of Bikougou (Gabon) ... The modeling of the experimental results is better achieved by application of. Freundlich adsorption isotherm and Langmuir adsorption isotherm concerning the adsorption of Cu ...

  8. Zn incorporation in CuInSe2: Particle size and strain effects on ...

    Indian Academy of Sciences (India)

    Administrator

    Zn incorporation in CuInSe2: Particle size and strain effects on microstructural ... size as well as tensile strain. The calculated ... X-ray diffraction analysis of CuInSe2 samples reported in figure 2 ... To estimate qualitative information regarding ...

  9. Structural and optical properties of Zn doped CuInS 2 thin films

    Indian Academy of Sciences (India)

    Copper indium sulphide (CIS) films were deposited by spray pyrolysis onto glass ... The effects of Zn (0–5%)molecular weight compared with CuInS2 Source and ... candidates for use as doped acceptors to fabricate CuInS2-based solar cells.

  10. Influence of cold isostatic pressing on the magnetic properties of Ni-Zn-Cu ferrite

    Science.gov (United States)

    Le, Trong Trung; Valdez-Nava, Zarel; Lebey, Thierry; Mazaleyrat, Frédéric

    2018-04-01

    In power electronics, there is the need to develop solutions to increase the power density of converters. Interleaved multicellular transformers allow interleaving many switching cells and, as a result, a possible increase in the power density. This converter is often composed of a magnetic core having the function of an intercell transformer (ICT) and, depending on the complexity of the designed architecture, its shape could be extremely complex. The switching frequencies (1-10 MHz) for the new wide band gap semiconductors (SiC, GaN) allow to interleave switching cell at higher frequencies than silicon-based semiconductors (materials, but their limit in frequency drive raises the need of higher frequency magnetic materials, such Ni-Zn ferrites. These materials can operate in medium and high power converters up to 10 MHz. We propose to use Ni0,30Zn0,57Cu0,15Fe2O4 ferrite and to compress it by cold isostatic pressing (CIP) into a a green ceramic block and to machine it to obtain the desired ICT of complex shape prior sintering. We compare the magnetic permeability spectra and hysteresis loops the CIP and uniaxially pressed ferrites. The effect of temperature and sintering time as well as high-pressure on properties will be presented in detail. The magnetic properties of the sintered cores are strongly dependent on the microstructure obtained.

  11. Preparation of highly oriented Al:ZnO and Cu/Al:ZnO thin films by sol-gel method and their characterization

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaprasath, G.; Murugan, R. [School of Physics, Alagappa University, Karaikudi 630 004, Tamil Nadu (India); Mahalingam, T. [Department of Electrical and Computer Engineering, Ajou University, Suwon 443-749 (Korea, Republic of); Hayakawa, Y. [Research Institute of Electronics, Shizuoka University, Hamamatsu 432-8011 (Japan); Ravi, G., E-mail: gravicrc@gmail.com [School of Physics, Alagappa University, Karaikudi 630 004, Tamil Nadu (India)

    2015-11-15

    Highly oriented thin films of Al doped ZnO (Al:ZnO) and Cu co-doped Al:ZnO (Cu/Al:ZnO) thin films were successfully deposited by sol–gel spin coating on glass substrates. The deposited films were characterized using X-ray diffraction analysis and found to exhibit hexagonal wurtzite structure with c-axis orientation. SEM images revealed that hexagonal rod shaped morphologies were grown perpendicular to the substrate surface due to repeated deposition process. High transmittance values were observed for pure ZnO compared to Al:ZnO and Cu/Al:ZnO thin films. The band gap widening is caused by the increase of carrier concentration, which is believed to be due to Burstein-Moss effect due to Al and Cu doping. PL spectra of Cu/Al:ZnO thin films indicate that the UV emission peaks slightly shifted towards lower energy side. XPS study was carried out for Zn{sub 0.80}Al{sub 0.10}Cu{sub 0.10}O thin films to analyze the binding energy of Al, Cu, Zn and O. Magnetic measurement studies exhibited ferromagnetic behavior at room temperature, which may be due to the increase in copper concentration in the doped films. The ferromagnetic behavior can be understood from the exchange coupling between localized ‘d’ spin of Cu ion mediated by free delocalized carriers. - Highlights: • High quality of Al:ZnO and Cu co-doped Al:ZnO thin films were fabricated by sol–gel method. • The XRD analyses revealed that the deposited thin films have hexagonal wurtzite structure. • XPS was carried out for Zn{sub 0.80}Al{sub 0.10}Cu{sub 0.10}O films to analyze the binding energy of Al, Cu, Zn and O. • SEM studies were made for Al:ZnO and Cu/Al:ZnO thin films. • RTFM was observed in Cu co-doped Al:ZnO thin films.

  12. Properties of ZnO/CuInSe/sub 2/ heterojunctions

    International Nuclear Information System (INIS)

    Qiu, C.X.; Shih, I.

    1986-01-01

    Low resistivity thin films of ZnO have been prepared by an rf sputtering technique with a target containing indium. It was found that the electrical resistivity of the deposited ZnO films was dependent on the indium content in the films. The deposition method was used to form ZnO/CuInSe/sub 2/ heterojunctions on Bridgman-grown monocrystalline CuInSe/sub 2/ samples. Electrical properties of the heterojunctions have been investigated. Spectral photovoltage variation was also measured

  13. A first-principles study of short range order in Cu-Zn

    International Nuclear Information System (INIS)

    Slutter, M.; Turchi, P.E.A.; Johnson, D.D.; Nicholson, D.M.; Stocks, G.M.; Pinski, F.J.

    1990-01-01

    Recently, measurements of short-range order (SRO) diffuse neutron scattering intensity have been performed on quenched Cu-Zn alloys with 22.4 to 31.1 atomic percent (a/o) Zn, and pair interactions were obtained by inverse Monte Carlo simulation. These results are compared to SRO intensities and effective pair interactions obtained from first-principles electronic structure calculations. The theoretical SRO intensities were calculated with the cluster variation method (CVM) in the tetrahedron-octahedron approximation with first-principles pain interactions as input. More generally, phase stability in the Cu-Zn alloy system is discussed, using ab-initio energetic properties

  14. Simultaneous increase in strength and ductility by decreasing interface energy between Zn and Al phases in cast Al-Zn-Cu alloy.

    Science.gov (United States)

    Han, Seung Zeon; Choi, Eun-Ae; Park, Hyun Woong; Lim, Sung Hwan; Lee, Jehyun; Ahn, Jee Hyuk; Hwang, Nong-Moon; Kim, Kwangho

    2017-09-22

    Cast-Al alloys that include a high amount of the second element in their matrix have comparatively high strength but low ductility because of the high volume fraction of strengthening phases or undesirable inclusions. Al-Zn alloys that have more than 30 wt% Zn have a tensile strength below 300 MPa, with elongation under 5% in the as-cast state. However, we found that after substitution of 2% Zn by Cu, the tensile strength of as-cast Al-Zn-Cu alloys was 25% higher and ductility was four times higher than for the corresponding Al-35% Zn alloy. Additionally, for the Al-43% Zn alloy with 2% Cu after 1 h solution treatment at 400 °C and water quenching, the tensile strength unexpectedly reached values close to 600 MPa. For the Al-33% Zn alloy with 2% Cu, the tensile strength was 500 MPa with 8% ductility. The unusual trends of the mechanical properties of Al-Zn alloys with Cu addition observed during processing from casting to the subsequent solution treatment were attributed to the precipitation of Zn in the Al matrix. The interface energy between the Zn particles and the Al matrix decreased when using a solution of Cu in Zn.

  15. Effect of foliar applied (Zn, Fe, Cu and Mn) in citrus production

    International Nuclear Information System (INIS)

    Khurshid, F.; Sarwar, S.; Khattak, R.A.

    2008-01-01

    A study was conducted to evaluate the impact of micronutrients (Zn, Fe, Cu and Mn) on sweet orange (Citrus Sinensis L.), blood red var., on farmer's orchard at Khanpur, district Haripur, NWFP, during 2002-03. Micronutrients were applied in foliar sprays over the canopy of each tree. The main effects and interactions of Zinc sulphate (Zn), iron sulphate (Fe), Copper Sulphate (Cu) and Manganese Sulphate (Mn) were studied in factorial combinations. A basal dose of nitrogen, phosphorus and potassium was applied at the rate 1.5, 1 and 1 kg tree/sup -1/. Zn, Fe, Cu and Mn were applied alone and in various combinations at the rate 0.115, 0.057, 0.05 and 0.13 kg in 100 liters of water. Application of micronutrients significantly increased Zn, Fe, Cu and Mn concentrations in leaves, compared with control. Zn treatments significantly increased the yield, number of fruit and total sugar. Manganese treatments significantly increased the total soluble solids and reduced the acidity of fruit juice. Other quality parameters, including fruit size, percent peel, percent pulp, sugar as well as total soluble solids, were improved with the application of Zn, Fe, Cu and Mn. (author)

  16. ZnO/Cu nanocomposite: a platform for direct electrochemistry of enzymes and biosensing applications.

    Science.gov (United States)

    Yang, Chi; Xu, Chunxiang; Wang, Xuemei

    2012-03-06

    Unique structured nanomaterials can facilitate the direct electron transfer between redox proteins and the electrodes. Here, in situ directed growth on an electrode of a ZnO/Cu nanocomposite was prepared by a simple corrosion approach, which enables robust mechanical adhesion and electrical contact between the nanostructured ZnO and the electrodes. This is great help to realize the direct electron transfer between the electrode surface and the redox protein. SEM images demonstrate that the morphology of the ZnO/Cu nanocomposite has a large specific surface area, which is favorable to immobilize the biomolecules and construct biosensors. Using glucose oxidase (GOx) as a model, this ZnO/Cu nanocomposite is employed for immobilization of GOx and the construction of the glucose biosensor. Direct electron transfer of GOx is achieved at ZnO/Cu nanocomposite with a high heterogeneous electron transfer rate constant of 0.67 ± 0.06 s(-1). Such ZnO/Cu nanocomposite provides a good matrix for direct electrochemistry of enzymes and mediator-free enzymatic biosensors.

  17. Preparation of Cu{sub 2}ZnSnS{sub 4} thin films by sulfurization of co-electroplated Cu-Zn-Sn precursors

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Hideaki; Kubo, Yuki; Jimbo, Kazuo; Maw, Win Shwe; Katagiri, Hironori; Yamazaki, Makoto; Oishi, Koichiro; Takeuchi, Akiko [Nagaoka National College of Technology, 888 Nishikatakai, Nagaoka, Niigata 940-8532 (Japan)

    2009-05-15

    Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films were prepared by sulfurization of electrodeposited Cu-Zn-Sn precursors. The Cu-Zn-Sn precursors were deposited on Mo-coated glass substrates in a one-step process from an electrolyte containing copper (II) sulfate pentahydrate, zinc sulfate heptahydrate, tin (II) chloride dehydrate and tri-sodium citrate dehydrate. The precursors were sulfurized by annealing with sulfur at temperatures of 580 C and 600 C in an N{sub 2} atmosphere. X-ray diffraction peaks attributable to CZTS were detected in the sulfurized films. Photovoltaic cells with the structure glass/Mo/CZTS/ CdS/ZnO:Al/Al were fabricated using the CZTS films by sulfurizing the electrodeposited precursors. The best photovoltaic cell performance was obtained with Zn-rich samples. An open-circuit voltage of 540 mV, a short-circuit current of 12.6 mA/cm{sup 2} and an efficiency of 3.16% were achieved. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Cu2ZnSnS4 solar cells fabricated by short-term sulfurization of sputtered Sn/Zn/Cu precursors under an H2S atmosphere

    International Nuclear Information System (INIS)

    Emrani, Amin; Rajbhandari, Pravakar P.; Dhakal, Tara P.; Westgate, Charles R.

    2015-01-01

    Synthesis of Cu 2 ZnSnS 4 (CZTS) thin films by short-term sulfurization of sputtered Sn/Zn/Cu precursors under ambient H 2 S is studied. The effect of the sulfurization processes on the film morphology, surface roughness, composition of the CZTS, and the crystallinity was investigated by using scanning electron microscopy, optical profiler, energy dispersive spectroscopy, and X-ray diffraction respectively. To further explore the CZTS layer, the following additional layers were deposited to complete the solar cells: CdS with chemical bath deposition; ZnO and Al 2 O 3 -doped ZnO with RF magnetron deposition; and, silver fingers as the front contact as the last layer. The optical and morphological properties of the CZTS films were investigated and compared. Subsequently, the electrical characteristics and the efficiencies of the regarding solar cells were analyzed. A maximum efficiency of 3.8% has been obtained for the fast sulfurization (30 min at 580 °C) and finally, the performance is compared with our best cell fabricated through the more common slow annealing. - Highlights: • Development of Cu 2 ZnSnS 4 (CZTS) solar cells using elemental metal sputtering • 112-oriented CZTS films with well-defined morphology obtained • Reported efficiency of 3.8% for a short-term annealing (less than 30 min) under ambient H 2 S • A detailed comparison between the fast and the more common slow annealing is reported

  19. Determination of toxicity limiting values of Zn, Cu, and Pb for oat and red clover

    Energy Technology Data Exchange (ETDEWEB)

    Hodenberg, A V; Finck, A

    1975-01-01

    Toxicity limiting values of Zn, Cu and Pb are determined in order to investigate the causes of growth damages in certain fields. Since the true toxicity limit is difficult to estimate, a somewhat higher content is called the toxicity limiting value resulting after the subtraction of a significant yield difference. The pot experiments with increasing fertilization of Zn, Cu and Pb in soil cultures gave the following results. For Zn, the toxicity limit is 410 ppm in oats at the beginning of tilling. In red clover six weeks of age, it is only 290 ppm of Zn and therefore much lower. For Cu, the toxicity limit is 20 ppm in oats at the beginning of tilling and 18 ppm in six weeks old red clover. For Pb, a toxic effect could be observed above 50 ppm, but this does not seem to be the true limit because of disturbing salt effects.

  20. Biosolids conditioning and the availability of Cu and Zn for rice Condicionamento de biossólidos e a disponibilidade de Cu e Zn para arroz

    Directory of Open Access Journals (Sweden)

    Adriana Marlene Moreno Pires

    2003-02-01

    Full Text Available Sewage treatment process is a factor to be considered for biosolid use in agriculture. The greatest sewage treatment facility of São Paulo State (Barueri/SP altered in the year 2000 of its sludge treatment. The addition of ferric chloride and calcium oxide was substituted by the addition of polymers. This change can modify heavy metal phytoavailability. A green house experiment, using 2 soils treated with biosolids (three with and one without polymers with and without polymers was performed to evaluate Cu and Zn phytoavailability using rice (Oryza sativa L. as test plant. Three kilograms of two soils (Haphorthox abd Hapludox were placed in pots and the equivalent to 50 Mg ha-1 (dry basis of biosolid was added and incorporated. The statistical design adopted was completely randomized experiment, with five treatments (control plus four different biossolids each soil and four replications. Soil pH before and after harvesting, Cu and Zn concentrations in shoot were evaluated. Tukey (5% was used to compare the results. DTPA, HCl 0.1 mol L-1 and Mehlich 3 were used to estimate soil available Cu and Zn. Amounts extracted were correlated to those presented in rice shoot, to evaluate the efficiency of predicting Cu and Zn phytoavailabilities. Biosolids with polymers presented higher Cu and Zn phytoavailabilities, possibly due to the lower pH of these residues. In this case soil presented lowest values of pH and plant shoot had highest. All extractants were representative of Cu and Zn availability to rice plants.O processo gerador do biossólido é um fator a ser considerado na avaliação do uso agrícola deste resíduo. Em 2000, a adição de cloreto férrico+cal virgem durante o tratamento do esgoto foi substituída pela adição de polieletrólitos na maior Estação de Tratamento de Esgotos de São Paulo (Barueri, o que pode gerar mudanças na fitodisponibilidade dos metais pesados. Um experimento em casa de vegetação, com dois solos (Latossolo

  1. Structural and optical properties of Cu2ZnSnS4 thin film absorbers from ZnS and Cu3SnS4 nanoparticle precursors

    International Nuclear Information System (INIS)

    Lin, Xianzhong; Kavalakkatt, Jaison; Kornhuber, Kai; Levcenko, Sergiu; Lux-Steiner, Martha Ch.; Ennaoui, Ahmed

    2013-01-01

    Cu 2 ZnSnS 4 (CZTS) has been considered as an alternative absorber layer to Cu(In,Ga)Se 2 due to its earth abundant and environmentally friendly constituents, optimal direct band gap of 1.4–1.6 eV and high absorption coefficient in the visible range. In this work, we propose a solution-based chemical route for the preparation of CZTS thin film absorbers by spin coating of the precursor inks composed of Cu 3 SnS 4 and ZnS NPs and annealing in Ar/H 2 S atmosphere. X-ray diffraction and Raman spectroscopy were used to characterize the structural properties. The chemical composition was determined by energy dispersive X-ray spectroscopy. Optical properties of the CZTS thin film absorbers were studied by transmission, reflection and photoluminescence spectroscopy

  2. Defects related room temperature ferromagnetism in Cu-implanted ZnO nanorod arrays

    International Nuclear Information System (INIS)

    Li, D.; Li, D.K.; Wu, H.Z.; Liang, F.; Xie, W.; Zou, C.W.; Shao, L.X.

    2014-01-01

    Highlights: • Room temperature ferromagnetism was observed in Cu-implanted ZnO nanorod arrays. • Cu-implanted ZnO nanorods show a saturation magnetization value of 1.82 μ B /Cu. • The origin of ferromagnetism can be explained by the defects related bound magnetic polarons. -- Abstract: Room temperature ferromagnetism (FM) was observed in Cu-implanted ZnO nanorod arrays. The implantation dose for Cu ions was 1 × 10 16 cm −2 and the implantation energy was 100 keV. The ion implantation induced defects and disorder has been observed by the XRD, PL and TEM experiments. The PL spectrum revealed a dominant luminescence peaks at 390 nm and a broad and strong green emission at 500–700 nm, which is considered to be related to the ionized oxygen vacancy. Cu-implanted ZnO nanorods annealed at 500 °C show a saturation magnetization value of 1.82 μ B /Cu and a positive coercive field of 68 Oe. The carrier concentration is not much improved after annealing and in the order of 10 16 cm −3 , which suggests that FM does not depend upon the presence of a significant carrier concentration. The origin of ferromagnetism behavior can be explained on the basis of electrons and defects that form bound magnetic polarons, which overlap to create a spin-split impurity band

  3. Effect of substrate on texture and mechanical properties of Mg-Cu-Zn thin films

    Science.gov (United States)

    Eshaghi, F.; Zolanvari, A.

    2018-04-01

    In this work, thin films of Mg-Cu-Zn with 60 nm thicknesses have been deposited on the Si(100), Al, stainless steel, and Cu substrates using DC magnetron sputtering. FESEM images displayed uniformity of Mg-Cu-Zn particles on the different substrates. AFM micrograph revealed the roughness of thin film changes due to the different kinds of the substrates. XRD measurements showed the existence of strong Mg (002) reflections and weak Mg (101) peaks. Residual stress and adhesion force have been measured as the mechanical properties of the Mg-Cu-Zn thin films. The residual stresses of thin films which have been investigated by X-ray diffraction method revealed that the thin films sputtered on the Si and Cu substrates endure minimum and maximum stresses, respectively, during the deposition process. However, the force spectroscopy analysis indicated that the films grew on the Si and Cu experienced maximum and minimum adhesion force. The texture analysis has been done using XRD instrument to make pole figures of Mg (002) and Mg (101) reflections. ODFs have been calculated to evaluate the distribution of the orientations within the thin films. It was found that the texture and stress have an inverse relation, while the texture and the adhesion force of the Mg-Cu-Zn thin films have direct relation. A thin film that sustains the lowest residual stresses and highest adhesive force had the strongest {001} basal fiber texture.

  4. Influence of cold isostatic pressing on the magnetic properties of Ni-Zn-Cu ferrite

    Directory of Open Access Journals (Sweden)

    Trong Trung Le

    2018-04-01

    Full Text Available In power electronics, there is the need to develop solutions to increase the power density of converters. Interleaved multicellular transformers allow interleaving many switching cells and, as a result, a possible increase in the power density. This converter is often composed of a magnetic core having the function of an intercell transformer (ICT and, depending on the complexity of the designed architecture, its shape could be extremely complex. The switching frequencies (1-10 MHz for the new wide band gap semiconductors (SiC, GaN allow to interleave switching cell at higher frequencies than silicon-based semiconductors (<1 MHz. Intercell transformers must follow this increase in frequency times-fold the number of switching cells. Current applications for ICT transformers use Mn-Zn based materials, but their limit in frequency drive raises the need of higher frequency magnetic materials, such Ni-Zn ferrites. These materials can operate in medium and high power converters up to 10 MHz. We propose to use Ni0,30Zn0,57Cu0,15Fe2O4 ferrite and to compress it by cold isostatic pressing (CIP into a a green ceramic block and to machine it to obtain the desired ICT of complex shape prior sintering. We compare the magnetic permeability spectra and hysteresis loops the CIP and uniaxially pressed ferrites. The effect of temperature and sintering time as well as high-pressure on properties will be presented in detail. The magnetic properties of the sintered cores are strongly dependent on the microstructure obtained.

  5. Porphyry Cu-Au mineralization in the Mirkuh Ali Mirza magmatic complex, NW Iran

    Science.gov (United States)

    Maghsoudi, A.; Yazdi, M.; Mehrpartou, M.; Vosoughi, M.; Younesi, S.

    2014-01-01

    The Mirkuh Ali Mirza Cu-Au porphyry system in East Azerbaijan Province is located on the western part of the Cenozoic Alborz-Azerbaijan volcanic belt. The belt is also an important Cu-Mo-Au metallogenic province in northwestern Iran. The exposed rocks in the study area consist of a volcaniclastic sequence, subvolcanic rocks and intermediate to mafic lava flows of Neogene age. The volcanic rocks show a typical subduction-related magmatic arc geological and geochemical signature, with low concentration of Nb, Ta, and Ti. Mineralization is hosted by Neogene dacitic tuff and porphyritic dacite situated at the intersections of northeast and northwest faults. Field observations, alteration zonation, geochemical haloes and isotopic data of the Mirkuh Ali Mirza magmatic complex show similarities with typical convergent margin Cu-Au porphyry type deposits. The following features confirm the classic model for Cu-Au porphyry systems: (a) close spatial association with high-K calcalkaline to shoshonitic rock related to post-collision extensional setting (b) low grade Cu (0.57%) (c) stockworks as well as disseminated sulfides (c) zonality of the alteration patterns from intense phyllic at the center to outward weak-phyllic, argillic, and propylitic (d) the presence of a pyritic halo (e) accompanied by sheeted veins and low-sulfidation epithermal gold (f) mineralization spatially associated with intersection of structures, (g) genetically related to diorite porphyry stocks at depth (h) geochemical zonation of (Cu ± Au ± Ag ± Bi) → (Cu + Mo ± Bi ± Au ± Pb ± Zn ± As) → (Au + Mo ± Pb ± Zn) → (As + Ag + Sb + Mn + Ba + Pb + Zn + Hg) → Hg from center to outwards (i) The range of sulfur isotopic values is approximately zero (interpreted to have magmatic source) and similar to other subduction-related porphyry Cu deposits.

  6. The determination of extinction coefficient of CuInS2, and ZnCuInS3 multinary nanocrystals.

    Science.gov (United States)

    Qin, Lei; Li, Dongze; Zhang, Zhuolei; Wang, Kefei; Ding, Hong; Xie, Renguo; Yang, Wensheng

    2012-10-21

    A pioneering work for determining the extinction coefficient of colloidal semiconductor nanocrystals (NCs) has been cited over 1500 times (W. Yu, W. Guo, X. G. Peng, Chem. Mater., 2003, 15, 2854-2860), indicating the importance of calculating NC concentration for further research and applications. In this study, the size-dependent nature of the molar extinction coefficient of "greener" CuInS(2) and ZnCuInS(3) NCs with emission covering the whole visible to near infrared (NIR) is presented. With the increase of NC size, the resulting quantitative values of the extinction coefficients of ternary CuInS(2) and quaternary ZnCuInS(3) NCs are found to follow a power function with exponents of 2.1 and 2.5, respectively. Obviously, a larger value of extinction coefficient is observed in quaternary NCs for the same size of particles. The difference of the extinction coefficient from both samples is clearly demonstrated due to incorporating ZnS with a much larger extinction coefficient into CuInS(2) NCs.

  7. Adsorption of multi-heavy metals Zn and Cu onto surficial sediments: modeling and adsorption capacity analysis.

    Science.gov (United States)

    Li, Shanshan; Zhang, Chen; Wang, Meng; Li, Yu

    2014-01-01

    Improved multiple regression adsorption models (IMRAMs) was developed to estimate the adsorption capacity of the components [Fe oxides (Fe), Mn oxides (Mn), organic materials (OMs), residuals] in surficial sediments for multi-heavy metal Zn and Cu. IMRAM is an improved version over MRAM, which introduces a computer program in the model developing process. As MRAM, Zn(Cu) IMRAM, and Cu(Zn) IMRAM again confirmed that there is significant interaction effects that control the adsorption of compounded Zn and Cu, which was neglected by additional adsorption model. The verification experiment shows that the relative deviation of the IMRAMs is less than 13%. It is revealed by the IMRAMs that Mn, which has the greatest adsorption capability for compounded Zn and Cu (54.889 and 161.180 mg/l, respectively), follows by interference adsorption capacity of Fe/Mn (-1.072 and -24.591 mg/l respectively). Zn and Cu influence each other through different mechanisms. When Zn is the adsorbate, compounded Cu mainly affects the adsorption capacities of Fe/Mn and Fe/Mn/OMs; while when Cu is the adsorbate, compounded Zn mainly exerts its effect on Mn, Fe/Mn, and Mn/OMs. It also shows that the compounded Zn or Cu weakened the interference adsorption of Fe/Mn, and meanwhile, strengthened the interference adsorption of Mn/OMs.

  8. Effect of Recrystallization and Natural Aging on Mechanical Properties of Al-Zn-Mg-Cu-Sc Alloys

    International Nuclear Information System (INIS)

    Yu, Min Kyu; Hong, Soon Hyung; Kwon, Oh Yeol; Lee, Yong Yeon

    2015-01-01

    In this study, the recrystallization volume fraction of the Al-Zn-Mg-Cu-Sc alloy after solid solution heat treatment varied with different temperatures (445℃ - 465℃). The highest elongation of the Al-Zn-Mg-Cu-Sc alloy was obtained at 465℃. Further, the hardness and strength of the solid solution heat treated Al-Zn-Mg-Cu-Sc alloy increased at room temperature due to G.P zone precipitates. The results confirmed that we can obtain advanced mechanical properties for the Al-Zn-Mg-Cu-Sc alloy from solid solution heat treatment and natural aging.

  9. Microstructure and properties of hot extruded Mg-3Zn-Y-xCu (x = 0, 1, 3, 5) alloys

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bao-sheng; Kuang, Ya-fei; Fang, Da-qing; Chai, Yue-sheng [Taiyuan Univ. of Science and Technology (China). College of Materials Science and Engineering; Taiyuan Univ. of Science and Technology (China). Engineering Research Center for Magnesium Alloys of Shanxi Province; Zhang, Yue-zhong [Taiyuan Univ. of Science and Technology (China). Engineering Research Center for Magnesium Alloys of Shanxi Province; Taiyuan Univ. of Science and Technology (China). College of Chemical and Biological Engineering

    2017-04-15

    In petroleum drilling engineering, materials with high strength and rapid degradation are required for degradable fracturing ball applications. In this work, the microstructure, mechanical properties, and corrosion behavior of extruded Mg-3Zn-Y-xCu (x = 0, 1, 3, 5 weight percent) alloys are investigated using optical microscopy, scanning electronic microscopy equipped with energy dispersive X-ray spectroscopy, X-ray diffraction, transmission electronic microscopy, compression tests, electrochemical measurements, and hydrogen evolution tests, to explore their potential as excellent candidate alloys for degradable fracturing ball applications. It is found that the Mg-3Zn-Y alloy is mainly composed of α-Mg, Mg{sub 3}Zn{sub 3}Y{sub 2}, and Mg{sub 3}Zn{sub 6}Y phases. After Cu addition, a new MgZnCu phase is formed, while the Mg{sub 3}Zn{sub 3}Y{sub 2} phase disappears. The Mg-3Zn-Y-3Cu alloy shows the highest compressive strength (473 MPa) and yield strength (402 MPa), mainly attributed to the combined effect of the fine-grain and dispersed precipitation of Mg{sub 3}Zn{sub 6}Y and MgZnCu. The corrosion rate of Mg-3Zn-Y-3Cu reaches 0.41 mm day{sup -1} in 3.5 wt.% KCl solution. Consequently, Mg-3Zn-Y-3Cu alloy is a suitable degradable fracturing ball-seat material.

  10. Pb, Cu, and Zn distributions at humic acid-coated metal-oxide surfaces

    Science.gov (United States)

    Wang, Yingge; Michel, F. Marc; Choi, Yongseong; Eng, Peter J.; Levard, Clement; Siebner, Hagar; Gu, Baohua; Bargar, John R.; Brown, Gordon E.

    2016-09-01

    Mineral surfaces are often coated by natural organic matter (NOM), which has a major influence on metal-ion sorption and sequestration because of the abundance of binding sites in such coatings and the changes they cause in local nanoscale environments. The effects of NOM coatings on mineral surfaces are, however, still poorly understood at the molecular level due to the complexity of these systems. In this study, we have applied long-period X-ray standing wave-fluorescence yield (LP-XSW-FY) spectroscopy to measure the partitioning of naturally present Cu(II) (0.0226%), Zn(II) (0.009%), and Pb(II) (∼0.0004%) between Elliott Soil Humic Acid (ESHA) coatings and three model single-crystal metal-oxide substrates: α-Al2O3 (0 0 0 1), α-Al2O3 (1 -1 0 2), and α-Fe2O3 (0 0 0 1). The competitive sorption effects among these metal ions for binding sites in the ESHA coatings and on the metal-oxide surfaces were investigated as a function of reaction time, calcium content, and solution pH. Pb(II) ions present in the ESHA coatings were found to redistribute to reactive α-Al2O3 (1 -1 0 2) and α-Fe2O3 (0 0 0 1) surfaces after 3 h of reaction (pH = 6.0, [Ca(II)] = 2 mM). Pb(II) partitioning onto these reactive metal-oxide surfaces increased with increasing reaction time (up to 7 d). In addition, the partitioning of Cu(II) and Zn(II) from the ESHA coating to the α-Fe2O3 (0 0 0 1) substrate increased slightly with reaction time (2.4% and 3.7% for Cu(II) and Zn(II), respectively, after 3 h and 6.4% and 7.7% for Cu(II) and Zn(II), respectively, after 72 h of reaction time). However, no changes in the partitioning of Cu(II) and Zn(II) onto the α-Al2O3 (1 -1 0 2) surface were observed with increasing reaction time, suggesting that these ions strongly complex with functional groups in the ESHA coatings. Similar results were obtained for Cu(II) and Zn(II) on the ESHA-coated α-Al2O3 (1 -1 0 2) surfaces in samples without the addition of calcium. However, the amounts of Pb

  11. Functional Performances of CuZnAl Shape Memory Alloy Open-Cell Foams

    Science.gov (United States)

    Biffi, C. A.; Casati, R.; Bassani, P.; Tuissi, A.

    2018-01-01

    Shape memory alloys (SMAs) with cellular structure offer a unique mixture of thermo-physical-mechanical properties. These characteristics can be tuned by changing the pore size and make the shape memory metallic foams very attractive for developing new devices for structural and functional applications. In this work, CuZnAl SMA foams were produced through the liquid infiltration of space holder method. In comparison, a conventional CuZn brass alloy was foamed trough the same method. Functional performances were studied on both bulk and foamed SMA specimens. Calorimetric response shows similar martensitic transformation (MT) below 0 °C. Compressive response of CuZnAl revealed that mechanical behavior is strongly affected by sample morphology and that damping capacity of metallic foam is increased above the MT temperatures. The shape memory effect was detected in the CuZnAl foams. The conventional brass shows a compressive response similar to that of the martensitic CuZnAl, in which plastic deformation accumulation occurs up to the cellular structure densification after few thermal cycles.

  12. Investigations on structural, vibrational and dielectric properties of nanosized Cu doped Mg-Zn ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Anand [School of Physics, Vigyan Bhavan, Devi Ahilya University, Khandwa Road Campus, Indore 452001 (India); Department of Physics, MEDICAPS Institute of Science and Technology, Pithampur 453331 (India); Rajpoot, Rambabu; Dar, M. A.; Varshney, Dinesh, E-mail: vdinesh33@rediffmail.com, E-mail: anand.212@gmail.com [School of Physics, Vigyan Bhavan, Devi Ahilya University, Khandwa Road Campus, Indore 452001 (India)

    2016-05-23

    Transition metal Cu{sup 2+} doped Mg-Zn ferrite [Mg{sub 0.5}Zn{sub 0.5-x}Cu{sub x}Fe{sub 2}O{sub 4} (0.0 ≤ x ≤ 0.5)] were prepared by sol gel auto combustion (SGAC) method to probe the structural, vibrational and electrical properties. X-ray diffraction (XRD) pattern reveals a single-phase cubic spinel structure without the presence of any secondary phase corresponding to other structure. The average particle size of the parent Mg{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} is found to be ~29.8 nm and is found to increase with Cu{sup 2+} doping. Progressive reduction in lattice parameter of Mg{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} has been observed due to difference in ionic radii of cations with improved Cu doping. Spinel cubic structure is further confirmed by Raman spectroscopy. Small shift in Raman modes towards higher wave number has been observed in doped Mg-Zn ferrites. The permittivity and dielectric loss decreases at lower doping and increases at higher order doping of Cu{sup 2+}.

  13. Hume-Rothery electron concentration rule across a whole solid solution range in a series of gamma-brasses in Cu-Zn, Cu-Cd, Cu-Al, Cu-Ga, Ni-Zn and Co-Zn alloy systems

    Science.gov (United States)

    Mizutani, U.; Noritake, T.; Ohsuna, T.; Takeuchi, T.

    2010-05-01

    The aim of the present work is to examine if the Hume-Rothery stabilisation mechanism holds across whole solid solution ranges in a series of gamma-brasses with especial attention to the role of vacancies introduced into the large unit cell. The concentration dependence of the number of atoms in the unit cell, N, for gamma-brasses in the Cu-Zn, Cu-Cd, Cu-Al, Cu-Ga, Ni-Zn and Co-Zn alloy systems was determined by measuring the density and lattice constants at room temperature. The number of itinerant electrons in the unit cell, e/uc, is evaluated by taking a product of N and the number of itinerant electrons per atom, e/a, for the transition metal element deduced earlier from the full-potential linearised augmented plane wave (FLAPW)-Fourier analysis. The results are discussed within the rigid-band model using as a host the density of states (DOS) derived earlier from the FLAPW band calculations for the stoichiometric gamma-brasses Cu5Zn8, Cu9Al4 and TM2Zn11 (TM = Co and Ni). A solid solution range of gamma-brasses in Cu-Zn, Cu-Cd, Cu-Al, Cu-Ga and Ni-Zn alloy systems is found to fall inside the existing pseudogap at the Fermi level. This is taken as confirmation of the validity of the Hume-Rothery stability mechanism for a whole solute concentration range of these gamma-brasses. An exception to this behaviour was found in the Co-Zn gamma-brasses, where orbital hybridisation effects are claimed to play a crucial role in stabilisation.

  14. Influence of Solution Heat Treatment on Structure and Mechanical Properties of ZnAl22Cu3 Alloy

    Directory of Open Access Journals (Sweden)

    Michalik R.

    2016-09-01

    Full Text Available The influence of solution heat treatment at 385°C over 10 h with cooling in water on the structure, hardness and strength of the ZnAl22Cu3 eutectoid alloy is presented in the paper. The eutectoid ZnAl22Cu3 alloy is characterized by a dendritic structure. Dendrites are composed of a supersaturated solid solution of Al in Zn. In the interdendritic spaces a eutectoid mixture is present, with an absence of the ε (CuZn4 phase. Solution heat treatment of the ZnAl22Cu3 alloy causes the occurrence of precipitates rich in Zn and Cu, possibly ε phase. Solution heat treatment at 385°C initially causes a significant decrease of the alloy hardness, although longer solution heat treatment causes a significant increase of the hardness as compared to the as-cast alloy.

  15. Phase controlled solvothermal synthesis of Cu_2ZnSnS_4, Cu_2ZnSn(S,Se)_4 and Cu_2ZnSnSe_4 Nanocrystals: The effect of Se and S sources on phase purity

    International Nuclear Information System (INIS)

    Pal, Mou; Mathews, N.R.; Paraguay-Delgado, F.; Mathew, X.

    2015-01-01

    In this study, we have reported the synthesis of Cu_2ZnSnSe_4 (CZTSe), Cu_2ZnSnS_4 (CZTS) and Cu_2ZnSn(S,Se)_4 (CZTSSe) nanocrystals with tunable band gap and composition obtained by solvothermal method. The crystalline structure, composition, morphology and optical properties of the nanoparticles were characterized by X-ray diffraction (XRD), Raman scattering, energy dispersive X-ray spectroscopy, transmission electron microscopy and diffuse reflectance (DR) spectroscopy. While the XRD patterns of CZTS and CZTSe nanoparticles prepared with elemental S/Se powder revealed the presence of phase pure nanoparticles, the CZTSSe nanoparticles obtained using a mixture of S and Se, were found to contain many secondary phases under the same synthesis protocol. Formation of impurity phases in CZTSSe sample, can be avoided by using a mixture of 1-dodecanethiol (DT; CH_3(CH_2)_1_1SH)/oleylamine (OLA) instead of S powder and following the same experimental procedure. The incorporation of S in CZTSe nanocrystals prepared in presence of DDT/OLA mixture was confirmed through structural and optical characterizations. The optical properties of the quaternary chalcogenide nanocrystals were found to vary with the chemical composition of the material. - Highlights: • Solvothermal synthesis of CZTS, CZTSSe and CZTSe nanocrystals and discussion on possible formation mechanism. • Use of dodecanethiol/oleylamine mixture to synthesize phase-pure CZTSSe nanocrystals. • Formation of impurity phases can be controlled with proper S and Se sources.

  16. Facile synthesis of core-shell Cu2O@ ZnO structure with enhanced photocatalytic H2 production

    Science.gov (United States)

    Zhang, Yong-Hui; Jiu, Bei-Bei; Gong, Fei-Long; Lu, Kuan; Jiang, Nan; Zhang, Hao-Li; Chen, Jun-Li

    2018-05-01

    Core-shell Cu2O@ZnO composites were synthesized successfully based on a one-pot hydrothermal method in the presence of dioctyl sulfosuccinate sodium salt (AOT) surfactant. The Cu2O can be converted to rough core-shell Cu2O@ZnO structure by adjusting the amount of zinc powder added. The as-synthesized Cu2O@ZnO composites exhibited excellent photocatalytic activity and the amount of H2 generated using these composites was 4.5-fold more than that produced with Cu2O cubes. A possible photocatalytic mechanism for the Cu2O@ZnO composites with enhanced photocatalytic activity could be the separation by ZnO of the effective charge carriers.

  17. Intrinsic point defects in off-stoichiometric Cu2ZnSnSe4: A neutron diffraction study

    Science.gov (United States)

    Gurieva, Galina; Valle Rios, Laura Elisa; Franz, Alexandra; Whitfield, Pamela; Schorr, Susan

    2018-04-01

    This work is an experimental study of intrinsic point defects in off-stoichiometric kesterite type CZTSe by means of neutron powder diffraction. We revealed the existence of copper vacancies (VCu), various cation anti site defects (CuZn, ZnCu, ZnSn, SnZn, and CuZn), as well as interstitials (Cui, Zni) in a wide range of off-stoichiometric polycrystalline powder samples synthesized by the solid state reaction. The results show that the point defects present in off-stoichiometric CZTSe agree with the off-stoichiometry type model, assuming certain cation substitutions accounting for charge balance. In addition to the known off-stoichiometry types A-H, new types (I-L) have been introduced. For the very first time, a correlation between the chemical composition of the CZTSe kesterite type phase and the occurring intrinsic point defects is presented. In addition to the off-stoichiometry type specific defects, the Cu/Zn disorder is always present in the CZTSe phase. In Cu-poor/Zn-rich CZTSe, a composition considered as the one that delivers the best photovoltaic performance, mainly copper vacancies, ZnCu and ZnSn anti sites are present. Also, this compositional region shows the lowest degree of Cu/Zn disorder.

  18. Effect of ageing time 200 °C on microstructure behaviour of Al-Zn-Cu-Mg cast alloys

    Directory of Open Access Journals (Sweden)

    Pratiwi Diah Kusuma

    2017-01-01

    Full Text Available Al-Zn-Cu-Mg is heat treatable alloy that can be used in many hightech applications, such as aerospace and military. The main objective of this study is to investigate the influence of ageing process in microstrucure behaviour of Al-9Zn-5Cu-4Mg cast alloy by performing SEM analysis and its correlation with hardness tests of as-cast Al-9Zn-5Cu-4Mg alloy and heat treated Al-9Zn-5Cu-4Mg cast alloy. The results show the deployment of precipitation spread over the dendrite and also the presence of second phases Mg3Zn3Al2 , Cu2FeAl7 , CuAl2, and CuMgAl2 in as-cast Al-9Zn-5Cu-4Mg alloy. The presence of all these second phases are affecting to the toughness of aluminium alloy and the presence of MgZn2 leads the impairment of hardness value of heat-treated Al-9Zn-5Cu-5Mg cast alloy.

  19. Syntheses, spectroscopic and thermal analyses of cyanide bridged heteronuclear polymeric complexes: [M(L)2Ni(CN)4]n (Ldbnd N-methylethylenediamine or N-ethylethylenediamine; Mdbnd Ni(II), Cu(II), Zn(II) or Cd(II))

    Science.gov (United States)

    Karaağaç, Dursun; Kürkçüoğlu, Güneş Süheyla

    2016-02-01

    Polymeric tetracyanonickelate(II) complexes of the type [M(L)2Ni(CN)4]n (Ldbnd N-methylethylenediamine (men) or N-ethylethylenediamine (neen); Mdbnd Ni(II), Cu(II), Zn(II) or Cd(II)) have been prepared and characterized by FT-IR, Raman spectroscopy, thermal and elemental analysis techniques. Additionally, FT-IR and Raman spectral analyses of men and neen have experimentally and theoretically investigated in the range of 4000-250 cm-1. The corresponding vibration assignments of men and neen are performed by using B3LYP density functional theory (DFT) method together with 6-31 G(d) basis set. The spectral features of the complexes suggest that the coordination environment of the M(II) ions are surrounded by the two symmetry related men and neen ligands and the two symmetry related N atom of cyanide groups, whereas the Ni(II) atoms are coordinated with a square-planar to four C atoms of the cyanide groups. Polymeric structures of the complexes consist of one dimensional alternative chains of [M(L)2]2+ and [Ni(CN)4]2- moieties. The thermal decompositions in the temperature range 30-700 °C of the complexes were investigated in the static air atmosphere.

  20. Changes in urinary Cu, Zn, and Se levels in cancer patients after treatment with Sha Shen Mai Men Dong Tang

    Directory of Open Access Journals (Sweden)

    Tung-Yuan Lai

    2016-04-01

    Full Text Available Sha Shen Mai Men Dong Tang (SMD-2; 沙參麥冬湯 shā shēn mài dōng tāng is a Chinese medicinal herb (CMH; 中草藥 zhōng cǎo yào used to treat symptoms associated with cancer therapy. The objective of this study was to assess the effect of SMD-2 on the levels of urinary copper (Cu, zinc (Zn, and selenium (Se in lung cancer patients and head and neck cancer patients receiving chemoradiotherapy. Forty-two head and neck cancer patients and 10 lung cancer patients participated in our clinical trial. Each patient received chemoradiotherapy for 4 weeks. In addition, each patient was treated with SMD-2 for 8 weeks, including 2 weeks prior to and after the chemoradiotherapy treatment. Comparison of urinary Cu, Zn, and Se levels and the ratios of Zn to Cu and Se to Cu at three time points in the two types of cancer were assessed using the generalized estimating equations (GEEs. After the patients received chemoradiotherapy for 4 weeks, SMD-2 treatment was found to be associated with a significant decrease in urinary Cu levels, whereas urinary Zn and Se levels increased significantly. In addition, the ratios of Zn to Cu and Se to Cu in the urine samples of these patients also increased significantly. Both the urinary Zn levels and the ratio of Zn to Cu in head and neck cancer patients were significantly higher than in lung cancer patients. Urinary Zn and Se levels and the ratios of Zn to Cu and Se to Cu, but not urinary Cu levels, increased significantly during and after treatment when assessed using the GEE model. The SMD-2 treatments significantly increased Zn and Se levels in the urine of head and neck cancer patients. Increased Zn and Se levels in urine strengthened immune system.

  1. Enhancement of ferromagnetic properties in Zn0.98Cu0.02O by additional Co doping

    International Nuclear Information System (INIS)

    Liu, Huilian; Zhang, Xu; Liu, Hongbo; Yang, Jinghai; Liu, Yang; Liu, Xiaoyan; Gao, Ming; Wei, Maobin; Cheng, Xin; Wang, Jian

    2013-01-01

    Highlights: •The samples were synthesized by sol–gel technology to dope up to 3% Co in ZnCuO. •After Co doped into Zn 0.98 Cu 0.02 O sample photoluminescence shows an increase in green emission. •The saturation magnetization increased with Co doping. -- Abstract: Zn 0.98 Cu 0.02 O and Zn 0.95 Cu 0.02 Co 0.03 O powders were synthesized by sol–gel method, and the effects of Co codoping on the structure, optical and magnetic properties of the Zn 0.98 Cu 0.02 O powders were studied in detail. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurement shows the Zn 0.98 Cu 0.02 O and Zn 0.95 Cu 0.02 Co 0.03 O powders were single phase with the ZnO wurtzite structure, and there was no ferromagnetic-related secondary phase in these powders. Moreover, these powders exhibited ferromagnetism at the room temperature investigated by the magnetic measurement, and the ferromagnetism of the Zn 0.98 Cu 0.02 O and Zn 0.95 Cu 0.02 Co 0.03 O samples were originated from the fact that the Cu ions and Co, Cu ions doped into the ZnO lattices, respectively. In addition, the saturation magnetization (Ms) was significantly increased with Co codoping due to the increased density of oxygen vacancies

  2. Composition controlled preparation of Cu–Zn–Sn precursor films for Cu{sub 2}ZnSnS{sub 4} solar cells using pulsed electrodeposition

    Energy Technology Data Exchange (ETDEWEB)

    Dang, Wenping; Ren, Xiaodong; Zi, Wei; Jia, Lujian [Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Liu, Shengzhong, E-mail: szliu@dicp.ac.cn [Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Dalian Institute of Chemical Physics, Dalian National Laboratory for Clean Energy, Chinese Academy of Sciences, Dalian, 116023 (China)

    2015-11-25

    A pulsed electrodeposition technique is developed to prepare Cu–Zn–Sn (CZT) precursor films for the Cu{sub 2}ZnSnS{sub 4} (CZTS) solar cells. The CZT precursor films are co-deposited on Mo-coated substrate using a cyanide-free electrolyte containing Zn (II) and Sn (II) salts. During the deposition, CuSO{sub 4} solution is supplied at controlled rate using a peristaltic pump to effectively regulate Cu{sup 2+} concentration. In addition, C{sub 6}H{sub 5}Na{sub 3}O{sub 7} is used as a coordination ligand to further balance activities of the Cu{sup 2+}, Sn{sup 2+} and Zn{sup 2+}. The CZTS films are then prepared using a sulfurization process to convert the electrodeposited CZT precursors at 580 °C in a sulphur atmosphere. The annealed thin films are characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), EDAX and X-ray photoelectron spectroscopy (XPS) techniques for their structural, morphological, compositional and chemical properties. It is found that the addition rate of Cu (II) has significant effects on the properties of the CZTS thin films. The CZTS film prepared using the optimized copper addition rate (0.15 ml/min) shows pure kesterite phase, Cu-poor and Zn-rich composition, compact morphology and good band gap ∼1.45 eV. Solar cells using the structure glass/Mo/CZTS/CdS/i-ZnO/ZnO:Al achieves a respectable external quantum efficiency and solar cell efficiency. - Highlights: • Developed a composition controlled pulsed electrodeposition for CZTS solar cells. • Electrochemistry and CZT composition regulated by measured Cu supply rate. • Complex chemistry used to regulate ion activities and electrodeposition. • Achieved a respectable CZTS solar cell quantum efficiency.

  3. Article Expression, Purification, and Characterization of Cu/ZnSOD from Panax Ginseng

    Directory of Open Access Journals (Sweden)

    Dayong Ding

    2014-06-01

    Full Text Available Superoxide dismutase (SOD has a strong antioxidant effect, but the traditional SOD extraction method is not the most efficient method of SOD amplification. In this study, we report the cloning of the Cu/ZnSOD gene from Panax ginseng into a temperature-regulated expression plasmid, pBV220. Cu/ZnSOD inclusion bodies were expressed in E. coli at a high level. Then, the inclusion bodies were purified by ion-exchange chromatography and molecular sieve chromatography. Finally, we obtained stable SOD in the bacterial broth, with a protein content of 965 mg/L and enzyme specific activity of 9389.96 U/mg. These results provide a foundation for future studies on the antioxidant mechanisms of ginseng and the development and application of ginseng Cu/ZnSOD.

  4. Novel inhibitors to Taenia solium Cu/Zn superoxide dismutase identified by virtual screening

    Science.gov (United States)

    García-Gutiérrez, P.; Landa-Piedra, A.; Rodríguez-Romero, A.; Parra-Unda, R.; Rojo-Domínguez, A.

    2011-12-01

    We describe in this work a successful virtual screening and experimental testing aimed to the identification of novel inhibitors of superoxide dismutase of the worm Taenia solium ( TsCu/Zn-SOD), a human parasite. Conformers from LeadQuest® database of drug-like compounds were selected and then docked on the surface of TsCu/Zn-SOD. Results were screened looking for ligand contacts with receptor side-chains not conserved in the human homologue, with a subsequent development of a score optimization by a set of energy minimization steps, aimed to identify lead compounds for in vitro experiments. Six out of fifty experimentally tested compounds showed μM inhibitory activity toward TsCu/Zn-SOD. Two of them showed species selectivity since did not inhibit the homologous human enzyme when assayed in vitro.

  5. Linking biosensor responses to Cd, Cu and Zn partitioning in soils

    International Nuclear Information System (INIS)

    Dawson, J.J.C.; Campbell, C.D.; Towers, W.; Cameron, C.M.; Paton, G.I.

    2006-01-01

    Soils bind heavy metals according to fundamental physico-chemical parameters. Bioassays, using bacterial biosensors, were performed in pore waters extracted from 19 contrasting soils individually amended with Cd, Cu and Zn concentrations related to the EU Sewage Sludge Directive. The biosensors were responsive to pore waters extracted from Zn amended soils but less so to those of Cu and showed no toxicity to pore water Cd at these environmentally relevant amended concentrations. Across the range of soils, the solid-solution heavy metal partitioning coefficient (K d ) decreased (p d values. Gompertz functions of Cu and Zn, K d values against luminescence explained the relationship between heavy metals and biosensors. Consequently, biosensors provide a link between biologically defined hazard assessments of metals and standard soil-metal physico-chemical parameters for determining critical metal loadings in soils. - Biosensors link biological hazard assessments of metals in soils with physico-chemical partitioning

  6. Decreasing Ni, Cu, Cd, and Zn heavy metal magnetite-bentonite nanocomposites and adsorption isotherm study

    Science.gov (United States)

    Eskandari, M.; Zakeri Khatir, M.; Khodadadi Darban, A.; Meshkini, M.

    2018-04-01

    This present study was conducted to investigate the effect of magnetite-bentonite nanocomposite on heavy metal removal from an effluent. For this purpose, magnetite-bentonite nanocomposite was prepared through the chemical method and characterized using x-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques, followed by studying the effect of produced nanocomposite on the removal of Ni2+, Cu2+, Cd2+, and Zn2+ heavy metal ions. The results showed that adsorption capacity of magnetite-bentonite nanocomposites for the studied ions is in the order of Zn2+ > Cd2+ > Cu2+ > Ni2+. Adsorption isotherms were drawn for Ni2+, Cu2+, Cd2+, and Zn2+ cations and found that cations adsorption on nanocomposite fit into Langmuir model.

  7. Cumulation of Cu, Zn, Cd, and Mn in Plants of Gardno Lake

    Directory of Open Access Journals (Sweden)

    Trojanowski J.

    2013-04-01

    Full Text Available In the present paper there have been shown the results of research on yhe content of Zn, Cd, Cu, Mn and Pb in chosen plants of Lake Gardno.The biggest concentration of those metals has been observed in Potamogton natans and Elodea canadensis, on average Zn – 34.9, Pb -2.77, Cd – 0.62, Cu – 3.24 and Mn – 257.4 μg g-1. It has been found that the over-ground parts of the plants under analysis cumulate several times less of heavy metals than their roots. The determined enrichment factors enabled the researchers to state that Cu in the examined plants is of natural origin while Mn, Cd and Zn – of anthropogenic origin.

  8. Optical properties of Cu implanted ZnO

    International Nuclear Information System (INIS)

    Cetin, A.; Kibar, R.; Ayvacikli, M.; Can, N.; Buchal, Ch.; Townsend, P.D.; Stepanov, A.L.; Karali, T.; Selvi, S.

    2006-01-01

    Nanoparticles of Cu have been made in zinc oxide crystals by ion implantation. The Cu ions were implanted at 400 keV into the (0 0 0 1) face of a single crystal. After implantation and after post-irradiation annealing there are numerous changes in the luminescence responses which include a variety of green and yellow emission bands. Following annealing at temperatures up to 1000 o C a green luminescence near 525 nm was observed which has been associated with the isolated Cu ions. The changes between as implanted and annealed luminescence signals suggests that the implants generate clustering or nanoparticle formation of Cu but anneals dissociate them

  9. ANTIMICROBIAL ACTIVITY OF Ag+, Cu2+, Zn2+, Mg2+ IONS DOPED CHITOSAN NANOPARTICLES

    Directory of Open Access Journals (Sweden)

    Sukhodub LB

    2015-04-01

    Full Text Available Modification by polymers and inorganic ions of the bioactive materials for orthopedic implants with the purpose of initiating controlled reactions in tissues that surround the implant, is one of the modern approaches in medical materials. A key feature of functional polymers is their ability to form complexes with various metal ions in solution. Chitosan is natural biopolymer with pronounced affinity to transition metal ions. Some researches prove the higher antimicrobial activity of Chitosan-metal complexes compared with pure Chitosan. The purpose of this work was the study of antimicrobial activity of Chitosan nanoparticles modified by metal ions Ag+, Cu2+, Zn2+, Mg2+ against reference strains S. aureus 25923 ATSS, E. coli ATCC 25922, C. albicans ATCC 885653 for their further use as components of the composite biomaterials for medical purpose.Chitosan nanoparticles suspension was prepared by known method based on the ionotropic gelation between chitosan and sodium tripolyphosphate.To obtain Chitosan-metal nanoparticles to the Chitosan suspension were added the corresponding metal ions aqueous solutions in quantity to match the concentration of metal ions of 200 ppm . Antibacterial activities of Ag+, Cu2+, Zn2+, Mg2+ ions doped Chitosan nanoparticles, pure Chitosan nanoparticles, metal ions and 1% (v/v acetic acid solution (it was used as solvent for Chitosan against bacteria were evaluated by determination of minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC in vitro. Muller– Hinton (MH broth and MH agar (Russia were used as growth media. The bacteria suspension for further use was prepared with concentration that corresponded 0,5units by McFarland scale. The MIC was determined by a broth dilution method. The results were read after 24 hours of experimental tubes incubation at 37 oC as equivalent to the concentration of the tube without visible growth. To evaluate MBC, a sample of 0,1 ml was transferred from

  10. Preparation and electrical properties of ZnO/CdS/Cu (In, Zn) Se2 (ZCIS) heterojunctions

    International Nuclear Information System (INIS)

    Ivanov, V.A.; Gremenok, V.F.; Zalesski, V.B.; Kovalevski, V.I.; Bente, K.

    2010-01-01

    Full text : Cu(In,Zn)Se 2 (ZCIS) is one of the most promising materials for commercial photovoltaic applications. This is due to the high absorption coefficient of approximately 105 cm - 1 in a wide spectral region and a band gap that is in principle adjustable between 1.05 eV for CuInSe 2 and 2.60 eV for ZnSe. Therefore they are suggested to be used in thin film solar cells as absorber as well a wide-gap window layers. The Cu/(In+Zn) ratio of the ZCIS layers is the important parameter for the physical properties of the semiconductor material as well for the solar cell applications. The presented results consider the preparation as well as the chemical, structural and physical characterization of the electrical properties of the ZnO/CdS/CuIn0, 94Zn0, 06Se2 thin films hetero junctions. The ZCIS films were prepared by two-step selenization of Cu-In-ZnSe layers under N2 flow by evaporating a solid Se source close to samples. Such technology is especially suited for developments of industrial processing of large area ZCIS films suitable for solar cells. Cu-In-ZnSe layers were deposited onto Mo-coated soda lime glass substrates by thermal evaporation or sputtering. The Zn content in the ZCIS films was controlled by choise of In/ZnSe ratio in the initial alloy. Buffer layers of CdS were deposited onto the ZCIS films in the chemical bath. The ZnO films were deposited onto CdS by thermal evaporation. The ZnO and CdS films were detected to be polycrystalline with thicknesses of 0.4im and 0.06im respectively and revealed n-type conductivity. The ''Leit-C'' conductive glue was used as electrical contacts. The effective area of each cell was about 0.8 cm2. Under non-illuminated conditions, I - V characteristics of the heterojunctions were approximately exponential at low voltages according to the standard diode equation I=Io[exp(eV/nkT)-1], with a slight deviation from this behaviour at high voltages due to a series of resistance effects. The capacitance of the heterojunctions

  11. Theoretical study of the magnetic behavior of hexanuclear Cu(II) and Ni(II) polysiloxanolato complexes.

    Science.gov (United States)

    Ruiz, Eliseo; Cano, Joan; Alvarez, Santiago; Caneschi, Andrea; Gatteschi, Dante

    2003-06-04

    A theoretical density functional study of the exchange coupling in hexanuclear polysiloxanolato-bridged complexes of Cu(II) and Ni(II) is presented. By calculating the energies of three different spin configurations, we can obtain estimates of the first-, second-, and third-neighbor exchange coupling constants. The study has been carried out for the complete structures of the Cu pristine cluster and of the chloroenclathrated Ni complex as well as for the hypotethical pristine Ni compound and for magnetically dinuclear analogues M(2)Zn(4) (M = Cu, Ni).

  12. Distribution of Ca, Fe, Cu and Zn in primary colorectal cancer and secondary colorectal liver metastases

    International Nuclear Information System (INIS)

    Al-Ebraheem, A.; Mersov, A.; Gurusamy, K.; Farquharson, M.J.

    2010-01-01

    A microbeam synchrotron X-ray fluorescence (μSRXRF) technique has been used to determine the localization and the relative concentrations of Zn, Cu, Fe and Ca in primary colorectal cancer and secondary colorectal liver metastases. 24 colon and 23 liver samples were examined, all of which were formalin fixed tissues arranged as microarrays of 1.0 mm diameter and 10 μm thickness. The distribution of these metals was compared with light transmission images of adjacent sections that were H and E stained to reveal the location of the cancer cells. Histological details were provided for each sample which enable concentrations of all elements in different tissue types to be compared. In the case of liver, significant differences have been found for all elements when comparing tumour, normal, necrotic, fibrotic, and blood vessel tissues (Kruskal Wallis Test, P<0.0001). The concentrations of all elements have also been found to be significantly different among tumour, necrotic, fibrotic, and mucin tissues in the colon samples (Kruskal Wallis Test, P<0.0001). The concentrations of all elements have been compared between primary colorectal samples and colorectal liver metastases. Concentration of Zn, Cu, Fe and Ca are higher in all types of liver tissues compared to those in the colon tissues. Comparing liver tumour and colon tumour samples, significant differences have been found for all elements (Mann Whitney, P<0.0001). For necrotic tissues, significant increase has been found for Zn, Ca, Cu and Fe (Mann Whitney, P<0.0001 for Fe and Zn, 0.014 for Ca, and 0.001 for Cu). The liver fibrotic levels of Zn, Ca, Cu and Fe were higher than the fibrotic colon areas (independent T test, P=0.007 for Zn and Mann Whitney test P<0.0001 for Cu, Fe and Ca). For the blood vessel tissue, the analysis revealed that the difference was only significant for Fe (P=0.009) from independent T test.

  13. Isolation and characterization of Cu/Zn-superoxide dismutase in Fasciola gigantica.

    Science.gov (United States)

    Lalrinkima, H; Raina, O K; Chandra, Dinesh; Jacob, Siju Susan; Bauri, R K; Chandra, Subhash; Yadav, H S; Singh, M N; Rialch, A; Varghese, A; Banerjee, P S; Kaur, Navneet; Sharma, Arvind

    2015-01-01

    A full-length complementary DNA (cDNA) encoding Cu/Zn-superoxide dismutase was isolated from Fasciola gigantica that on nucleotide sequencing showed a close homology (98.9%) with Cu/Zn-superoxide dismutase (SOD) of the temperate liver fluke, F. hepatica. Expression of the gene was found in all the three developmental stages of the parasite viz. adult, newly excysted juvenile and metacercaria at transcriptional level by reverse transcription-polymerase chain reaction (RT-PCR) and at the protein level by Western blotting. F. gigantica Cu/Zn-SOD cDNA was cloned and expressed in Escherichia coli. Enzyme activity of the recombinant protein was determined by nitroblue tetrazolium (NBT)-polyacrylamide gel electrophoresis (PAGE) and this activity was inactivated by hydrogen peroxide but not by sodium azide, indicating that the recombinant protein is Cu/Zn-SOD. The enzyme activity was relatively stable at a broad pH range of pH 4.0-10.0. Native Cu/Zn-superoxide dismutase protein was detected in the somatic extract and excretory-secretory products of the adult F. gigantica by Western blotting. NBT-PAGE showed a single Cu/Zn-SOD present in the somatic extract while three SODs are released ex vivo by the adult parasite. The recombinant superoxide dismutase did not react with the serum from buffaloes infected with F. gigantica. The role of this enzyme in defense by the parasite against the host reactive oxygen species is discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Synthesis of ZnO Nanowires via Hotwire Thermal Evaporation of Brass (CuZn) Assisted by Vapor Phase Transport of Methanol

    OpenAIRE

    Tamil Many K. Thandavan; Siti Meriam Abdul Gani; Chiow San Wong; Roslan Md Nor

    2014-01-01

    Zinc oxide (ZnO) nanowires (NWs) were synthesized using vapor phase transport (VPT) and thermal evaporation of Zn from CuZn. Time dependence of ZnO NWs growth was investigated for 5, 10, 15, 20, 25, and 30 minutes. Significant changes were observed from the field electron scanning electron microscopy (FESEM) images as well as from the X-ray diffraction (XRD) profile. The photoluminescence (PL) profile was attributed to the contribution of oxygen vacancy, zinc interstitials, and hydrogen defec...

  15. Leaching potential of pervious concrete and immobilization of Cu, Pb and Zn using pervious concrete.

    Science.gov (United States)

    Solpuker, U; Sheets, J; Kim, Y; Schwartz, F W

    2014-06-01

    This paper investigates the leaching potential of pervious concrete and its capacity for immobilizing Cu, Pb and Zn, which are common contaminants in urban runoff. Batch experiments showed that the leachability of Cu, Pb and Zn increased when pHconcrete might function to attenuate contaminant migration. A porous concrete block was sprayed with low pH water (pH=4.3±0.1) for 190 h. The effluent was highly alkaline (pH~10 to 12). In the first 50 h, specific conductance and trace-metal were high but declined towards steady state values. PHREEQC modeling showed that mixing of interstitial alkaline matrix waters with capillary pore water was required in order to produce the observed water chemistry. The interstitial pore solutions seem responsible for the high pH values and relatively high concentrations of trace metals and major cations in the early stages of the experiment. Finally, pervious concrete was sprayed with a synthetic contaminated urban runoff (10 ppb Cu, Pb and Zn) with a pH of 4.3±0.1 for 135 h. It was found that Pb immobilization was greater than either Cu or Zn. Zn is the most mobile among three and also has the highest variation in the observed degree of immobilization. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Theoretical and experimental studies of the ZnSe/CuInSe2 heterojunction band offset

    International Nuclear Information System (INIS)

    Nelson, A.J.; Schwerdtfeger, C.R.; Wei, S.; Zunger, A.; Rioux, D.; Patel, R.; Hoechst, H.

    1993-01-01

    We report first-principles band structure calculations that show that ZnSe/CuInSe 2 has a significant valence band offset (VBO, ΔE v ): 0.70±0.05 eV for the relaxed interface and 0.60±0.05 eV for the coherent interface. These large values demonstrate the failure of the common anion rule. This is traced to a stronger Cu,d-Se,p level repulsion in CuInSe 2 than the Zn,d-Se,p repulsion in ZnSe. The VBO was then studied by synchrotron radiation soft x-ray photoemission spectroscopy. ZnSe overlayers were sequentially grown in steps on n-type CuInSe 2 (112) single crystals at 200 degree C. In situ photoemission measurements were acquired after each growth in order to observe changes in the valence band electronic structure as well as changes in the In 4d and Zn 3d core lines. Results of these measurements reveal that the VBO is ΔE v =0.70±0.15 eV, in good agreement with the first-principles prediction

  17. Passivation of Cu-Zn alloy on low carbon steel electrodeposited from a pyrophosphate medium

    Science.gov (United States)

    Yavuz, Abdulcabbar; Yakup Hacıibrahimoğlu, M.; Bedir, Metin

    2018-01-01

    The motivation of this study is to understand whether zinc-based alloy also has a passivation behaviour similar to zinc itself. Cu-Zn alloys were electrodeposited potentiostatically from a pyrophosphate medium on a carbon steel electrode and their corrosion behaviours were studied. Pt and carbon steel electrodes were used in order to examine the corrosion/passivation behaviour of bare Cu, bare Zn and Cu-Zn alloy coatings. The passivation behaviour of all brass-modified electrodes having Zn content between 10% and 100% was investigated. The growth potential affects the morphology and structure of crystals. The brass coatings are more porous than their pure components. The crystalline structure of Cu-Zn alloys can be obtained by changing the deposition potential. The zinc content in brass increases when the deposition voltage applied decreases. However, the growth potential and the ratio of zinc in brass do not affect the passivation behaviour of the resulting alloys. The coatings obtained by applying different growth potentials were immersed in tap water for 24 h to compare their corrosion behaviours with carbon steel having pitting formation.

  18. Analysis on Cu and Zn Concentrations in Agricultural Soils of Ili District, Xinjiang Autonomous Region, China

    Directory of Open Access Journals (Sweden)

    YANG Jing-na

    2015-02-01

    Full Text Available The aim of this work is mainly to investigate the contents of copper(Cuand zinc(Znin agricultural soils to provide basic infor-mation for the establishment of green and organic production base in Ili District, Xinjiang Autonomous Region. 600 topsoil samples of the a-gricultural land were collected from eight counties of Ili District, and the contents of Cu and Zn were determined by AAS after microwave di-gestion. The statistics analysis showed that the mean contents of Cu and Zn in the agricultural soils of Ili District were 28.68 mg·kg-1 and 83.17 mg·kg-1, respectively. The concentrations of Cu in the agricultural soils of Ili District ranged from 11.07 mg·kg-1 to 59.90 mg·kg-1, 85% of which ranged from 20 mg·kg-1 to 40 mg·kg-1; and the concentrations of Zn in the agricultural soils of Ili District ranged from 39.58 mg·kg-1 to 160.40 mg·kg-1, 90%of which ranged from 60 mg·kg-1 to 110 mg·kg-1. Furthermore, compared the Cu and Zn contents of the tested soils among the eight counties, Cu contents in Tekes County were higher than other counties, while Zn contents showed little difference. The con-tents of Cu and Zn in the tested soils were all below the threshold values that were established in the national environmental quality standard for soils(secondary standards, GB 15618-1995, but about 7% and 21% were higher than the Cu and Zn background values of soil in Ili District, respectively. Furthermore, the concentrations of Cu and Zn in soils of Ili District accord with the environmental requirements for or-ganic and green production base regulated by national standard of organic products(GB/T 19630-2011and industrial standard of green food(NY/T 391-2013.

  19. Determination of Ca, Fe, Cu and Zn content in hair by EDXRF method

    International Nuclear Information System (INIS)

    Yang Mingtai; Chen Jinhua; Qi Honglian; Gao Ge

    1994-01-01

    The authors introduce an analysing method that can determine simultaneously Ca, Fe, Cu and Zn in hair by using energy-dispersive X ray fluorescence analyzer of tube-excite type made in China. The added element Y is used as internal standard in hair sample. The hair is resolved by chemical reagent to make test sample, then the energy-dispersive X ray fluorescence analyzer is used to determine Ca, fe, Cu and Zn contents in hair sample. The lower limits of detection are 7 x 10 -6 , 1 x 10 -6 , 4 x 10 -6 , 3 x 10 -6 , respectively. Correlative coefficients of variations are 6%, 1%, 2%, 2%

  20. HEAVY METALS (Ni, Cu, Zn AND Cd CONTENT IN SERUM OF RAT FED GREEN MUSSELS

    Directory of Open Access Journals (Sweden)

    Muhammad Yudhistira Azis

    2015-11-01

    Full Text Available Green mussel (Perna viridis can playing role as bio-indicator or biomonitoring agent for heavy-metalcontaminations in the sea. In this research, the concentrations of four elements Ni, Cu, Zn and Cd in P. viridis and in the serum of rat which orally feed by P. viridis were determined by Atomic Absorption Spectrometry (AAS following dry acid digestion. Parameter analysis was evaluated by determining confidence limit for the obtained results. The result showed that there was a sequence of heavy-metal content in green mussels sample and laboratory rats serum, such as Ni < Cd < Cu < Zn. Keywords: heavy metals, green mussels, laboratory rats serum, AAS

  1. Structure and Function of Cu(I)- and Zn(II)-ATPases

    DEFF Research Database (Denmark)

    Sitsel, Oleg; Grønberg, Christina; Autzen, Henriette Elisabeth

    2015-01-01

    Copper and zinc are micronutrients essential for the function of many enzymes while also being toxic at elevated concentrations. Cu(I)- and Zn(II)-transporting P-type ATPases of subclass 1B are of key importance for the homeostasis of these transition metals, allowing ion transport across cellular...... membranes at the expense of ATP. Recent biochemical studies and crystal structures have significantly improved our understanding of the transport mechanisms of these proteins, but many details about their structure and function remain elusive. Here we compare the Cu(I)- and Zn(II)-ATPases, scrutinizing...

  2. Ultra-thin Cu2ZnSnS4 solar cell by pulsed laser deposition

    DEFF Research Database (Denmark)

    Cazzaniga, Andrea Carlo; Crovetto, Andrea; Yan, Chang

    2017-01-01

    We report on the fabrication of a 5.2% efficiency Cu2ZnSnS4 (CZTS) solar cell made by pulsed laser deposition (PLD) featuring an ultra-thin absorber layer (less than 450 nm). Solutions to the issues of reproducibility and micro-particulate ejection often encountered with PLD are proposed. At the ......We report on the fabrication of a 5.2% efficiency Cu2ZnSnS4 (CZTS) solar cell made by pulsed laser deposition (PLD) featuring an ultra-thin absorber layer (less than 450 nm). Solutions to the issues of reproducibility and micro-particulate ejection often encountered with PLD are proposed...

  3. Phytotoxic effects of Cu and Zn on soybeans grown in field-aged soils: their additive and interactive actions.

    Science.gov (United States)

    Kim, Bojeong; McBride, Murray B

    2009-01-01

    A field pot experiment was conducted to investigate the interactive phytotoxicity of soil Cu and Zn on soybean plants [Glycine max (L.) Merr.]. Two soils (Arkport sandy loam [coarse-loamy, mixed, active, mesic Lamellic Hapludalf] and Hudson silty clay loam [fine, illitic, mesic Glossaquic Hapludalf]) spiked with Cu, Zn, and combinations of both to reach the final soil metal range of 0 to 400 mg kg(-1) were tested in a 2-yr bioassay after 1 yr of soil-metal equilibration in the field. The soluble and easily-extractable fraction of soil Zn (or Cu), estimated by dilute CaCl2, increased linearly in response to the total Zn (or Cu) added. This linearity was, however, strongly affected where soils were treated with both metals in combination, most notably for Zn, as approximately 50% more of soil Zn was extracted into solution when the Cu level was high. Consequently, added Zn is less likely to be stabilized by aging than added Cu when both metals are present in field soils. The predictive model relating soil metal extractability to plant Zn concentration also revealed a significant Cu-Zn interaction. By contrast, the interaction between the two metals contributed little to explain plant Cu uptake. The additive action of soil Cu and Zn was of considerable importance in explaining plant biomass reduction. This work clearly demonstrates the critical roles of the properties of the soil, the nature of the metal, and the level of other toxic metals present on the development of differential phytotoxicity due to soil Cu and Zn.

  4. Cyclotron production of {sup 64}Cu by deuteron irradiation of {sup 64}Zn

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, K. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (Vatican City State, Holy See,) (Italy)]. E-mail: kamel.abbas@jrc.it; Kozempel, J. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Charles University Prague, Faculty of Science, Department of Organic and Nuclear Chemistry, 128 43 Prague (Czech Republic); Bonardi, M. [LASA, Radiochemistry Laboratory, University and INFN, via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Groppi, F. [LASA, Radiochemistry Laboratory, University and INFN, via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Alfarano, A. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Holzwarth, U. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Simonelli, F. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Hofman, H. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Horstmann, W. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Menapace, E. [ENEA, Applied Physics Division, Bologna (Italy); Leseticky, L. [Charles University Prague, Faculty of Science, Department of Organic and Nuclear Chemistry, 128 43 Prague (Czech Republic); Gibson, N. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy)

    2006-09-15

    The short-lived (12.7 h half-life) {sup 64}Cu radioisotope is both a {beta} {sup +} and a {beta} {sup -} emitter. This property makes {sup 64}Cu a promising candidate for novel medical applications, since it can be used simultaneously for therapeutic application of radiolabelled biomolecules and for diagnosis with PET. Following previous work on {sup 64}Cu production by deuteron irradiation of natural zinc, we report here the production of this radioisotope by deuteron irradiation of enriched {sup 64}Zn. In addition, yields of other radioisotopes such as {sup 61}Cu, {sup 67}Cu, {sup 65}Zn, {sup 69m}Zn, {sup 66}Ga and {sup 67}Ga, which were co-produced in this process, were also measured. The evaporation code ALICE-91 and the transport code SRIM 2003 were used to determine the excitation functions and the stopping power, respectively. All the nuclear reactions yielding the above-mentioned radioisotopes were taken into account in the calculations both for the natural and enriched Zn targets. The experimental and calculated yields were shown to be in reasonable agreement. The work was carried out at the Scanditronix MC-40 Cyclotron of the Institute for Health and Consumer Protection of the Joint Research Centre of the European Commission (Ispra site, Italy). The irradiations were carried out with 19.5 MeV deuterons, the maximum deuteron energy obtainable with the MC-40 cyclotron.

  5. Ab initio investigation on hydrogen adsorption capability in Zn and Cu-based metal organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Tanuwijaya, V. V., E-mail: viny.veronika@gmail.com [Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung Jalan Ganeca 10 Gd. T.P. Rachmat, Bandung 40132 (Indonesia); Hidayat, N. N., E-mail: avantgarde.vee@gmail.com; Agusta, M. K., E-mail: kemal@fti.itb.ac.id; Dipojono, H. K., E-mail: dipojono@tf.itb.ac.id

    2015-09-30

    One of the biggest challenge in material technology for hydrogen storage application is to increase hydrogen uptake in room temperature and pressure. As a class of highly porous material, Metal-Organic Frameworks (MOF) holds great potential with its tunable structure. However, little is known about the effect of metal cluster to its hydrogen storage capability. Investigation on this matter has been carried out carefully on small cluster of Zn and Cu-based MOF using first principles method. The calculation of two distinct building units of MOFs, namely octahedral and paddle-wheel models, have been done with B3LYP density functional method using 6-31G(d,p) and LANL2DZ basis sets. From geometry optimization of Zn-based MOF linked by benzene-dicarboxylate (MOF-5), it is found that hydrogen tends to keep distance from metal cluster group and stays above benzene ring. In the other hand, hydrogen molecule prefers to stay atop of the exposed Cu atom in Cu-based MOF system linked by the same linker group (Cu-bdc). Calculated hydrogen binding enthalpies for Zn and Cu octahedral cages at ZnO{sub 3} sites are 1.64kJ/mol and 2.73kJ/mol respectively, while hydrogen binding enthalpies for Zn and Cu paddle-wheel cages calculated on top of metal atoms are found to be at 6.05kJ/mol and 6.10kJ/mol respectively. Major difference between Zn-MOF-5 and Cu-bdc hydrogen uptake performance might be caused by unsaturated metal sites present in Cu-bdc system and the influence of their geometric structures, although a small difference on binding energy in the type of transition metal used is also observed. The comparison between Zn and Cu-based MOF may contribute to a comprehensive understanding of metal clusters and the importance of selecting best transition metal for design and synthesis of metal-organic frameworks.

  6. Gelsolin-Cu/ZnSOD interaction alters intracellular reactive oxygen species levels to promote cancer cell invasion

    KAUST Repository

    Tochhawng, Lalchhandami; Deng, Shuo; Ganesan, Pugalenthi; Kumar, Alan Prem; Lim, Kiat Hon; Yang, Henry; Hooi, Shing Chuan; Goh, Yaw Chong; Maciver, Sutherland K.; Pervaiz, Shazib; Yap, Celestial T.

    2016-01-01

    , and this is mediated via gelsolin's effects in elevating intracellular superoxide (O2 .-) levels. We also provide evidence for a novel physical interaction between gelsolin and Cu/ZnSOD, that inhibits the enzymatic activity of Cu/ZnSOD, thereby resulting in a sustained

  7. Overexpressing the Sedum alfredii Cu/Zn Superoxide Dismutase Increased Resistance to Oxidative Stress in Transgenic Arabidopsis

    Directory of Open Access Journals (Sweden)

    Zhen Li

    2017-06-01

    Full Text Available Superoxide dismutase (SOD is a very important reactive oxygen species (ROS-scavenging enzyme. In this study, the functions of a Cu/Zn SOD gene (SaCu/Zn SOD, from Sedum alfredii, a cadmium (Cd/zinc/lead co-hyperaccumulator of the Crassulaceae, was characterized. The expression of SaCu/Zn SOD was induced by Cd stress. Compared with wild-type (WT plants, overexpression of SaCu/Zn SOD gene in transgenic Arabidopsis plants enhanced the antioxidative defense capacity, including SOD and peroxidase activities. Additionally, it reduced the damage associated with the overproduction of hydrogen peroxide (H2O2 and superoxide radicals (O2•-. The influence of Cd stress on ion flux across the root surface showed that overexpressing SaCu/Zn SOD in transgenic Arabidopsis plants has greater Cd uptake capacity existed in roots. A co-expression network based on microarray data showed possible oxidative regulation in Arabidopsis after Cd-induced oxidative stress, suggesting that SaCu/Zn SOD may participate in this network and enhance ROS-scavenging capability under Cd stress. Taken together, these results suggest that overexpressing SaCu/Zn SOD increased oxidative stress resistance in transgenic Arabidopsis and provide useful information for understanding the role of SaCu/Zn SOD in response to abiotic stress.

  8. ZnSe passivation layer for the efficiency enhancement of CuInS2 quantum dots sensitized solar cells

    International Nuclear Information System (INIS)

    Peng, Zhuoyin; Liu, Yueli; Zhao, Yinghan; Chen, Keqiang; Cheng, Yuqing; Kovalev, Valery; Chen, Wen

    2014-01-01

    Highlights: • ZnSe is employed as passivation layer in CuInS 2 quantum dots sensitized solar cells. • Slight red-shift has been occurred in UV–vis absorption spectra with ZnSe coating. • CuInS 2 based solar cells coated by ZnSe have better efficiency than that of ZnS. • Higher rate of charge transport can be produced after coating with ZnSe. -- Abstract: The effect of ZnSe passivation layer is investigated in the CuInS 2 quantum dot sensitized solar cells, which is used to improve the photovoltaic performance. The CuInS 2 quantum dot sensitized TiO 2 photo-anodes are prepared by assembly linking technique, and then deposited by the ZnSe passivation layer using the successive ionic layer absorption and reaction technique. The optical absorption edge and photoluminescence peak have slightly red-shifted after the passivation layer coating. Under solar light illumination, the ZnSe passivation layer based CuInS 2 quantum dot sensitized solar cells have the higher photovoltaic efficiency of 0.95% and incident photon conversion efficiency response than that of pure CuInS 2 based solar cells and ZnS passivation layer based solar cells, as the electron injection rate becomes faster after coating with ZnSe passivation layer

  9. Effect of electrodeposition and annealing of ZnO on optical and photovoltaic properties of the p-Cu2O/n-ZnO solar cells

    International Nuclear Information System (INIS)

    Hussain, Sajad; Cao Chuanbao; Nabi, Ghulam; Khan, Waheed S.; Usman, Zahid; Mahmood, Tariq

    2011-01-01

    Highlights: → The p-Cu 2 O/n-ZnO heterojunction was fabricated by using electrodeposition and rf sputtering techniques, respectively. → The effect of electrodeposition on optical and photovoltaic properties of the p-Cu 2 O/n-ZnO solar cells has been examined. → The preannealing of ZnO thin films has enhanced the efficiency of solar cells. → The efficiency of the solar cell was measured 0.46%. - Abstract: Cu 2 O/ZnO p-n heterojunction solar cells were fabricated by rf sputtering deposition of n-ZnO layer, followed by electrodeposition of p-Cu 2 O layer. The different electrodeposition potentials were applied to deposit Cu 2 O on ZnO. The particle size, crystal faces, crystallinity of Cu 2 O is important factor which determine the p-n junction interface and consequently their effect on the performance of the heterojunction solar cell. It is observed that at -0.6 V, p-Cu 2 O film generates fewer surface states in the interband region due to the termination of [1 1 0] resulting in higher efficiency (0.24%) with maximum particle size (53 nm). The bandgap of Cu 2 O at this potential is found to be 2.17 eV. Furthermore, annealing of ZnO film was performed to get rid of deteriorating one and two dimensional defects, which always reduce the performance of solar cell significantly. We found that the solar cell performance efficiency is nearly doubled by increasing the annealing temperature of ZnO thin films due to increasing electrical conductance and electron mobility. Doping studies and fine tuning of the junction morphology will be necessary to further improve the performance of Cu 2 O/ZnO heterojunction solar cells.

  10. EXAFS analysis of a human Cu,Zn SOD isoform focused using non-denaturing gel electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Chevreux, Sylviane; Roudeau, Stephane; Deves, Guillaume; Ortega, Richard [Laboratoire de Chimie Nucleaire Analytique et Bioenvironnementale, CNRS UMR5084, Universite Bordeaux 1, Chemin du Solarium, F-33175 Gradignan cedex (France); Solari, Pier Lorenzo [Synchrotron SOLEIL, L' Orme des Merisiers, BP 48, F-91192 Gif-sur-Yvette cedex, Saint-Aubin (France); Alliot, Isabelle; Testemale, Denis; Hazemann, Jean Louis, E-mail: ortega@cenbg.in2p3.f [FAME, ESRF, 6 rue Jules Horowitz, BP220, F-38043 Grenoble cedex (France)

    2009-11-15

    Isoelectric point isoforms of a metalloprotein, copper-zinc superoxide dismutase (CuZnSOD), separated on electrophoresis gels were analyzed using X-ray Absorption Spectroscopy. Mutations of this protein are involved in familial cases of amyotrophic lateral sclerosis. The toxicity of mutants could be relied to defects in the metallation state. Our purpose is to establish analytical protocols to study metallation state of protein isoforms such as those from CuZnSOD. We previously highlighted differences in the copper oxidation state between CuZnSOD isoforms using XANES. Here, we present the first results for EXAFS analyses performed at Cu and Zn K-edge on the majoritary expressed isoform of human CuZnSOD separated on electrophoresis gels.

  11. EXAFS analysis of a human Cu,Zn SOD isoform focused using non-denaturing gel electrophoresis

    Science.gov (United States)

    Chevreux, Sylviane; Solari, Pier Lorenzo; Roudeau, Stéphane; Deves, Guillaume; Alliot, Isabelle; Testemale, Denis; Hazemann, Jean Louis; Ortega, Richard

    2009-11-01

    Isoelectric point isoforms of a metalloprotein, copper-zinc superoxide dismutase (CuZnSOD), separated on electrophoresis gels were analyzed using X-ray Absorption Spectroscopy. Mutations of this protein are involved in familial cases of amyotrophic lateral sclerosis. The toxicity of mutants could be relied to defects in the metallation state. Our purpose is to establish analytical protocols to study metallation state of protein isoforms such as those from CuZnSOD. We previously highlighted differences in the copper oxidation state between CuZnSOD isoforms using XANES. Here, we present the first results for EXAFS analyses performed at Cu and Zn K-edge on the majoritary expressed isoform of human CuZnSOD separated on electrophoresis gels.

  12. EXAFS analysis of a human Cu,Zn SOD isoform focused using non-denaturing gel electrophoresis

    International Nuclear Information System (INIS)

    Chevreux, Sylviane; Roudeau, Stephane; Deves, Guillaume; Ortega, Richard; Solari, Pier Lorenzo; Alliot, Isabelle; Testemale, Denis; Hazemann, Jean Louis

    2009-01-01

    Isoelectric point isoforms of a metalloprotein, copper-zinc superoxide dismutase (CuZnSOD), separated on electrophoresis gels were analyzed using X-ray Absorption Spectroscopy. Mutations of this protein are involved in familial cases of amyotrophic lateral sclerosis. The toxicity of mutants could be relied to defects in the metallation state. Our purpose is to establish analytical protocols to study metallation state of protein isoforms such as those from CuZnSOD. We previously highlighted differences in the copper oxidation state between CuZnSOD isoforms using XANES. Here, we present the first results for EXAFS analyses performed at Cu and Zn K-edge on the majoritary expressed isoform of human CuZnSOD separated on electrophoresis gels.

  13. Solid Liquid Interdiffusion Bonding of Zn4Sb3 Thermoelectric Material with Cu Electrode

    Science.gov (United States)

    Lin, Y. C.; Lee, K. T.; Hwang, J. D.; Chu, H. S.; Hsu, C. C.; Chen, S. C.; Chuang, T. H.

    2016-10-01

    The ZnSb intermetallic compound may have thermoelectric applications because it is low in cost and environmentally friendly. In this study, a Zn4Sb3 thermoelectric element coated with a Ni barrier layer and a Ag reaction layer was bonded with a Ag-coated Cu electrode using a Ag/Sn/Ag solid-liquid interdiffusion bonding process. The results indicated that a Ni5Zn21 intermetallic phase formed easily at the Zn4Sb3/Ni interface, leading to sound adhesion. In addition, Sn film was found to react completely with the Ag layer to form a Ag3Sn intermetallic layer having a melting point of 480°C. The resulting Zn4Sb3 thermoelectric module can be applied at the optimized operation temperature (400°C) of Zn4Sb3 material as a thermoelectric element. The bonding strengths ranged from 14.9 MPa to 25.0 MPa, and shear tests revealed that the Zn4Sb3/Cu-joints fractured through the interior of the thermoelectric elements.

  14. Antiproliferative effects of ZnO, ZnO-MTCP, and ZnO-CuMTCP nanoparticles with safe intensity UV and X-ray irradiation.

    Science.gov (United States)

    Sadjadpour, Susan; Safarian, Shahrokh; Zargar, Seyed Jalal; Sheibani, Nader

    2016-01-01

    In photodynamic therapy (PDT) of cancer both the light and the photosensitizing agent are normally harmless, but in combination they could result in selective tumor killing. Zinc oxide nanoparticles were synthesized and coated with the amino acid cysteine to provide an adequate arm for conjugation with porphyrin photosensitizers (meso-tetra (4-carboxyphenyl) porphyrin [MTCP] and CuMTCP). Porphyrin-conjugated nanoparticles were characterized by TEM, FTIR, and UV-vis, and fluorescence spectrophotometry. The 3-[4, 5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to measure cell viability in the presence or absence of porphyrin conjugates following UV and X-ray irradiation. The uptake of the porphyrin-conjugated ZnO nanoparticles by cells was detected using fluorescence microscopy. Our results indicated that the survival of T-47D cells was significantly compromised in the presence of ZnO-MTCP-conjugated nanostructures with UV light exposure. Exhibition of cytotoxic activity of ZnO-MTCP for human prostate cancer (Du145) cells occurred at a higher concentration, indicating the more resistant nature of these tumor cells. ZnO-CuMTCP showed milder cytotoxic effects in human breast cancer (T-47D) and no cytotoxic effects in Du145 with UV light exposure, consistent with its lower cytotoxic potency as well as cellular uptake. Surprisingly, none of the ZnO-porphyrin conjugates exhibited cytotoxic effects with X-ray irradiation, whereas ZnO alone exerted cytotoxicity. Thus, ZnO and ZnO-porphyrin nanoparticles with UV or X-ray irradiation may provide a suitable treatment option for various cancers. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

  15. Fabrication of p-CuO/n-ZnO heterojunction diode via sol-gel spin coating technique

    Energy Technology Data Exchange (ETDEWEB)

    Prabhu, Rajeev R., E-mail: rajeevrprabhu@gmail.com [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi 682 022 (India); Saritha, A.C.; Shijeesh, M.R. [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi 682 022 (India); Jayaraj, M.K. [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi 682 022 (India); Centre for Advanced Materials, Cochin University of Science and Technology, Kochi 682 022 (India)

    2017-06-15

    Highlights: • Facile all-solution growth of nanostructured p-CuO and n-ZnO TSO films is reported. • Annealing the films in air affects the structural, electrical and optical properties. • p-n heterojunction using these films was fabricated in ITO/n-ZnO/p-CuO/Au structure. • Transparent heterojunction diode performed well with a V{sub on} of 2.5 V and n of 3.15. • Fabricated p-CuO/n-ZnO heterojunction diode can be used for UV detector application. - Abstract: We report a facile all-solution approach for the growth of nanostructured p-CuO and n-ZnO thin films. The influence of annealing temperature on the physical properties of CuO and ZnO thin films was examined. XRD and Raman spectra depict the structural and phase purity of solution grown CuO and ZnO films. The electrical as well as the optical properties of thin films were also studied. The average optical transmission of CuO and ZnO thin films in the visible spectral region was found to be above 80 and 95% respectively. Band gap energy variations on annealing temperature were investigated for CuO as well as ZnO films. Surface morphology analyzed by FESEM shows that the films are very smooth. All solution grown p-n heterojunction using p-CuO and n-ZnO films was fabricated in the structure ITO/n-ZnO/p-CuO/Au which showed rectification behavior with a turn on voltage of 2.5 V and an ideality factor of 3.15.

  16. Electrochemical synthesis of p-Cu_2O/n-ZnO nanorods hetero-junction for photovoltaic application

    International Nuclear Information System (INIS)

    Rokade, A. V.; Rondiya, S. R.; Jadhavar, A. A.; Pandharkar, S. M.; Karpe, S. D.; Diwate, K. D.; Jadkar, S. R.

    2016-01-01

    Development of high performance visible light responsive solar cell materials has attracted wide interest due to their potential applications in the energy industries. In this work, ZnO nanorods films were successfully prepared on the ITO coated glass substrates via simple three electrode electrochemical deposition route. The Cu_2O nanoparticles were then electrodeposited on the surface of ZnO nanorods to form p-Cu_2O/n-ZnO core-shell hetero-structure. The synthesized ZnO, Cu_2O films and p-Cu_2O/n-ZnO hetero-structure were characterized by low angle x-ray diffraction, scanning electron microscopy, and UV-Visible spectrophotometer. Due to the hierarchical morphologies and core-shell structure, p-Cu_2O/n-ZnO hetero-structure shows a prominent visible-light-driven photocatalytic performance under the low intensity light irradiation. The obtained results suggest that it is possible to synthesize ZnO nanorods, Cu_2O films and p-Cu_2O/n-ZnO core-shell hetero-structure by a simple, cost effective and environment friendly electrodeposition process which can be useful for water splitting and solar cell device fabrication.

  17. Extremely High Phosphate Sorption Capacity in Cu-Pb-Zn Mine Tailings.

    Science.gov (United States)

    Huang, Longbin; Li, Xiaofang; Nguyen, Tuan A H

    2015-01-01

    Elevated inorganic phosphate (Pi) concentrations in pore water of amended tailings under direct revegetation may cause toxicity in some native woody species but not native forbs or herb species, all of which are key constituents in target native plant communities for phytostabilizing base metal mine tailings. As a result, Pi sorption capacity has been quantified by a conventional batch procedure in three types of base metal mine tailings sampled from two copper (Cu)-lead (Pb)-zinc (Zn) mines, as the basis for Pi-fertiliser addition. It was found that the Pi-sorption capacity in the tailings and local soil was extremely high, far higher than highly weathered agricultural soils in literature, but similar to those of volcanic ash soils. The Langmuir P-sorption maximum was up to 7.72, 4.12, 4.02 and 3.62 mg P g-1 tailings, in the fresh tailings of mixed Cu-Pb-Zn streams (MIMTD7), the weathered tailings of mixed Cu-Pb-Zn streams (MIMTD5), EHM-TD (fresh Cu-stream, high magnetite content) and local soil (weathered shale and schist), respectively. Physicochemical factors highly correlated with the high Pi-sorption in the tailings were fine particle distribution, oxalate and dithionite-citrate-bicarbonate extractable Fe (FeO and Fed), oxalate-extractable Al and Mn, and the levels of soluble Cd and Zn, and total S and Fe. Large amounts of amorphous Fe oxides and oxyhydroxides may have been formed from the oxidation of pyritic materials and redox cycles of Fe-minerals (such as pyrite (FeS2), ankerite (Ca(Fe Mg)(CO3)2 and siderite (FeCO3), as indicated by the extractable FeO values. The likely formation of sparingly soluble Zn-phosphate in the Pb-Zn tailings containing high levels of Zn (from sphalerite ((Zn,Fe)S, ZnS, (Zn,Cd)S)) may substantially lower soluble Zn levels in the tailings through high rates of Pi-fertiliser addition. As a result, the possibility of P-toxicity in native plant species caused by the addition of soluble phosphate fertilizers would be minimal.

  18. Extremely High Phosphate Sorption Capacity in Cu-Pb-Zn Mine Tailings.

    Directory of Open Access Journals (Sweden)

    Longbin Huang

    Full Text Available Elevated inorganic phosphate (Pi concentrations in pore water of amended tailings under direct revegetation may cause toxicity in some native woody species but not native forbs or herb species, all of which are key constituents in target native plant communities for phytostabilizing base metal mine tailings. As a result, Pi sorption capacity has been quantified by a conventional batch procedure in three types of base metal mine tailings sampled from two copper (Cu-lead (Pb-zinc (Zn mines, as the basis for Pi-fertiliser addition. It was found that the Pi-sorption capacity in the tailings and local soil was extremely high, far higher than highly weathered agricultural soils in literature, but similar to those of volcanic ash soils. The Langmuir P-sorption maximum was up to 7.72, 4.12, 4.02 and 3.62 mg P g-1 tailings, in the fresh tailings of mixed Cu-Pb-Zn streams (MIMTD7, the weathered tailings of mixed Cu-Pb-Zn streams (MIMTD5, EHM-TD (fresh Cu-stream, high magnetite content and local soil (weathered shale and schist, respectively. Physicochemical factors highly correlated with the high Pi-sorption in the tailings were fine particle distribution, oxalate and dithionite-citrate-bicarbonate extractable Fe (FeO and Fed, oxalate-extractable Al and Mn, and the levels of soluble Cd and Zn, and total S and Fe. Large amounts of amorphous Fe oxides and oxyhydroxides may have been formed from the oxidation of pyritic materials and redox cycles of Fe-minerals (such as pyrite (FeS2, ankerite (Ca(Fe Mg(CO32 and siderite (FeCO3, as indicated by the extractable FeO values. The likely formation of sparingly soluble Zn-phosphate in the Pb-Zn tailings containing high levels of Zn (from sphalerite ((Zn,FeS, ZnS, (Zn,CdS may substantially lower soluble Zn levels in the tailings through high rates of Pi-fertiliser addition. As a result, the possibility of P-toxicity in native plant species caused by the addition of soluble phosphate fertilizers would be minimal.

  19. Substrate type < 111 >-Cu{sub 2}O/<0001 >-ZnO photovoltaic device prepared by photo-assisted electrodeposition

    Energy Technology Data Exchange (ETDEWEB)

    Zamzuri, Mohd, E-mail: zamzuri@tf.me.tut.ac.jp [Department of Mechanical Eng., Toyohashi University of Technology, 1-1 Hibari Gaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan); School of Manufacturing Eng., Universiti Malaysia Perlis, Kampus Tetap Pauh Putra, Jln Arau-Changlun, 02600 Arau, Perlis (Malaysia); Sasano, Junji [Department of Mechanical Eng., Toyohashi University of Technology, 1-1 Hibari Gaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan); Mohamad, Fariza Binti [Faculty of Electrical & Electronic Eng., University Tun Hussein Onn Malaysia, 86400, Parit Raja, Batu Pahat, Johor (Malaysia); Izaki, Masanobu [Department of Mechanical Eng., Toyohashi University of Technology, 1-1 Hibari Gaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan)

    2015-11-30

    The substrate-type < 0001 > ZnO/<111 > Cu{sub 2}O photovoltaic (PV) device has been constructed by electrodeposition of a < 111 >-p-Cu{sub 2}O layer on an Au(111)/Si wafer substrate followed by stacking the n-ZnO layer by electrodeposition during light irradiation in aqueous solutions. The PV device was fabricated by stacking the Al:ZnO-window by sputtering and the top Al electrode by vacuum evaporation. The < 0001 >-ZnO layer was composed of aggregates of hexagonal columnar grains grown in the direction normal to the surface, and pores could be observed between the ZnO grains at the deposition time last 1800 s. The < 0001 >-ZnO/<111 >-Cu{sub 2}O PV device showed a photovoltaic performance under AM1.5 illumination, and showed the improved short-circuit current density of 5.87 mA cm{sup −2} by stacking the AZO-TCO due to the increase in the diffusion length of the carrier. - Highlights: • Substrate type ZnO/Cu{sub 2}O photovoltaic devices only by electrodeposition • ZnO layer was stacked on the Cu{sub 2}O layer by photo-assisted electrodeposition. • AZO/ZnO/Cu{sub 2}O photovoltaic devices with a short-circuit current density of 5.87 mA cm{sup −2}.

  20. Fusion and characterization of an alloy Cu-Zn-Al-Ni of nuclear interest; Fusion y caracterizacion de una aleacion Cu-Zn-Al-Ni de interes nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Santana M, J.S

    2003-07-01

    The present work is the result of the study of a non ferrous quatenary alloy of Cu-Zn-Al-Ni (Foundry 3), it was chosen of a series of alloys to obtain so much information of its microstructural properties like mechanical, evaluating them and comparing them with the previously obtained ternary alloys of Cu-AI-Ni (Foundry 1) and Cu-Zn-AI (Foundry 2) identified as alloys of memory effect and superalloys. These were carried out starting from the foundry of their pure elements of Cu, Zn, Al, Ni. When physically having the ingot of each alloy, different techniques were used for their characterization. The used techniques were through the metallographic analysis, by scanning electron microscopy (SEM), X-ray dispersive energy spectroscopy (EDS), X-ray diffraction (XRD), mechanical essays and Rockwell hardness. The non ferrous quaternary alloy Cu-Zn-AI-Ni by means of the metallographic analysis didn't show significant differences in their three sections (superficial, longitudinal and transverse) since result an homogeneous alloy at the same that the both ternaries. The grain size of the quaternary alloy is the finest while the ternary alloy of Cu-AI-Ni is the one that obtained the biggest grain size. Through MEB together with the analysis by EDS and the mapping of the elements that constitute each alloy, show that the three foundries were alloyed, moreover the presence of aggregates was also observed in the Foundries 2 and 3. These results by means of the analysis of XRD corroborate that these alloys have more of two elements. Relating the microstructural properties with those mechanical show us that as minor was the grain size, better they were his mechanical properties, in this case that of the quaternary alloy. With regard to the test of Rockwell hardness the Foundry 1 were the softest with the temper treatment, while that the Foundries 2 and 3 were the hardest with this same treatment, being still harder the Foundry 2 but with very little difference, for what great

  1. Levels Of Mn, Fe, Ni, Cu, Zn And Cd, In Effluent From A Sewage ...

    African Journals Online (AJOL)

    This study reports the results of preliminary investigation of heavy metal levels-Ni, Cd, Fe, Zn, Cu and Mn; pH; temperature and electrical conductivity in effluents from a sewage treatment oxidation pond and its receiving stream. The heavy metal concentrations were determined with Inductively Coupled Plasma-Mass ...

  2. CuZnSOD gene expression and its relationship with anti-oxidative ...

    African Journals Online (AJOL)

    ... and the minimum in the LY. The proportion of gene expression was positively correlated with the anti-oxidative capacity in muscle. The expression of the CuZnSOD gene was positively correlated with meat colour and tenderness; and negatively correlated with marbling score, drip loss, cooking loss and intramuscular fat.

  3. Heavy metals (Cd, Pb, Cu, Zn) in mudfish and sediments from three ...

    African Journals Online (AJOL)

    driniev

    2004-04-02

    Apr 2, 2004 ... and analysed for Cd and Pb by electro-thermal AAS, and for Cu and Zn by flame AAS. ... measurements and the dolomitic hard water and high pH of the Mooi River water .... Copper and zinc were determined by flame analysis at 324.8 nm ... were placed separately in clean 20 ml glass vials and one ml de-.

  4. Transient behavior of Cu/ZnO-based methanol synthesis catalysts

    DEFF Research Database (Denmark)

    Vesborg, Peter Christian Kjærgaard; Chorkendorff, Ib; Knudsen, Ida

    2009-01-01

    Time-resolved measurements of the methanol synthesis reaction over a Cu/ZnO-based catalyst reveal a transient methanol production that depends on the pretreatment gas. Specifically, the methanol production initially peaks after a pretreatment with an intermediate mixture of H2 and CO (20–80% H2...

  5. Quantifying the promotion of Cu catalysts by ZnO for methanol synthesis

    DEFF Research Database (Denmark)

    Kuld, Sebastian; Thorhauge, Max; Falsig, Hanne

    2016-01-01

    Promoter elements enhance the activity and selectivity of heterogeneous catalysts. Here, we show how methanol synthesis from synthesis gas over copper (Cu) nanoparticles is boosted by zinc oxide (ZnO) nanoparticles. By combining surface area titration, electron microscopy, activity measurement, d...

  6. Effect of solution heat treatment time on a rheocast Al-Zn-Mg-Cu alloy

    CSIR Research Space (South Africa)

    Mazibuko, NE

    2011-06-01

    Full Text Available During rheo-high pressure die casting (R-HPDC) of Al-Zn-Mg-Cu alloys a coarse eutectic phase is formed. This eutectic phase is difficult to take into solution because of its size and it would require longer solution heat treatment times...

  7. Synthesis of ZnO-CuO/MCM-48 photocatalyst for the degradation of organic pollutions.

    Science.gov (United States)

    Duan, Yongzheng; Shen, Yulian

    2017-07-01

    The photocatalytic properties of ZnO-CuO catalysts supported on siliceous MCM-48 (Mobil Composition of Matter No. 48) for the degradation of organic pollutions such as methylene blue and salicylic acid under UV light irradiation were investigated. These catalysts were prepared by impregnation of MCM-48 with a mixed aqueous solution of copper acetate and zinc acetate. X-ray diffraction, N 2 -physisorption, high resolution transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and photoluminescence were used to characterize these samples. Results from characterizations showed that the addition of ZnO to CuO/MCM-48 could markedly improve the photocatalytic degradation properties. The enhanced photocatalytic behaviors of ZnO-CuO/MCM-48 may be due to the formation of p-n heterojunctions between ZnO and CuO, resulting in the effective separation of photogenerated electron-hole pairs. Moreover, the photocatalysts were easily recovered and reused for five cycles without considerable loss of activity.

  8. Effect of citric acid on formation of oxides of Cu and Zn in modified ...

    Indian Academy of Sciences (India)

    tions such as sensors, catalysts, lithium-ion batteries, supercapacitors ... Metal Oxides (TMO), NiO (nickel oxide), CuO (copper oxide) and ZnO (zinc oxide) are ..... Bulletin 1452 241. 24. Ellingham H J T 1944 J. Soc. Chem. Ind. (London). 63 125.

  9. Behaviors of heavy metals (Cd, Cu, Ni, Pb and Zn) in soil amended with composts.

    Science.gov (United States)

    Gusiatin, Zygmunt Mariusz; Kulikowska, Dorota

    2016-09-01

    This study investigated how amendment with sewage sludge compost of different maturation times (3, 6, 12 months) affected metal (Cd, Cu, Ni, Pb, Zn) bioavailability, fractionation and redistribution in highly contaminated sandy clay soil. Metal transformations during long-term soil stabilization (35 months) were determined. In the contaminated soil, Cd, Ni and Zn were predominately in the exchangeable and reducible fractions, Pb in the reducible fraction and Cu in the reducible, exchangeable and oxidizable fractions. All composts decreased the bioavailability of Cd, Ni and Zn for up to 24 months, which indicates that cyclic amendment with compost is necessary. The bioavailability of Pb and Cu was not affected by compost amendment. Based on the reduced partition index (IR), metal stability in amended soil after 35 months of stabilization was in the following order: Cu > Ni = Pb > Zn > Cd. All composts were more effective in decreasing Cd, Ni and Zn bioavailability than in redistributing the metals, and increasing Cu redistribution more than that of Pb. Thus, sewage sludge compost of as little as 3 months maturation can be used for cyclic amendment of multi-metal-contaminated soil.

  10. The essential dynamics of Cu, Zn superoxide dismutase : Suggestion of intersubunit communication

    NARCIS (Netherlands)

    Chillemi, G; Falconi, M; Amadei, A; Zimatore, G; Desideri, A; DiNola, A

    A 300-ps molecular dynamics simulation of the whole Cu, Zn superoxide dismutase dimer has been carried out in water, and the trajectory has been analyzed by the essential dynamics method. The results indicate that the motion is defined by few preferred directions identified by the first four to six

  11. Determination of field-based sorption isotherms for Cd, Cu, Pb and Zn in Dutch soils

    NARCIS (Netherlands)

    Otte JG; Grinsven JJM van; Peijnenburg WJGM; Tiktak A; LBG; ECO

    1999-01-01

    Sorption isotherms for metals in soil obtained in the laboratory generally underpredict the observed metal content in the solid phase in the field. Isotherms based on in-situ data are therefore required. The aim of this study is to obtain field-based sorption isotherms for Cd, Cu, Pb and Zn as input

  12. The synthesis of higher alcohols using modified Cu/ZnO/Al@#2@#O@#3@# catalysts

    NARCIS (Netherlands)

    Slaa, J.C.; Slaa, J.C.; van Ommen, J.G.; Ross, J.R.H.; Ross, J.R.H.

    1992-01-01

    This paper gives a review of research work in the synthesis of higher alcohols over catalysts based on Cu/ZnO/Al2O3, emphasizing three main topics: (i) the effect on selectivity of the addition of several compounds to this catalyst, (ii) the effect on selectivity of the reaction conditions used, and

  13. Hydrothermal synthesis of ZnSe:Cu quantum dots and their luminescent mechanism study by first-principles

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Qingshuang; Bai, Yijia; Han, Lin; Deng, Xiaolong [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Graduate School, Chinese Academy of Sciences, Beijing 10049 (China); Wu, Xiaojie [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Wang, Zhongchang [WPI Research Center, Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Liu, Xiaojuan, E-mail: lxjuan@ciac.jl.cn [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Meng, Jian, E-mail: jmeng@ciac.jl.cn [State Key Laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2013-11-15

    An one-pot synthesis of aqueous ZnSe:Cu nanocrystals (NCs) is realized in aqueous solution by a facile yet efficient hydrothermal technique. The dopant emission spectrum of the NCs is tunable, spanning a wide range from 438 to 543 nm. Room-temperature quantum yield for the NCs prepared at the optimal conditions reaches as high as 20% without any post-treatment. The ZnSe:Cu NCs prepared in a neutral aqueous solution (pH=8) are remarkably stable and exhibit comparatively high photoluminescent quantum yield (PL QY) as high as 17%. First-principles pseudopotential calculations using plane-wave basis functions have been performed. The formation energies of copper ions occupied in the interstitial octahedron and substitutional tetrahedral Zn{sup 2+} sites have been calculated. The occupation of copper ions in the interstitial octahedral site is found to be more thermodynamics-facilitated by −0.98 eV. The density of state analysis indicates that the Cu-related emission is primary dominated by the substitutional tetrahedral Cu ions, and the large dopant related emission width of ZnSe:Cu NCs originated from the corresponding Cu 3d impurity band. Highlights: • One-pot synthesis of aqueous ZnSe:Cu nanocrystals with tunable emission and high QY%. • ZnSe:Cu NCs exhibit high QY% at neutral pH suitable for biological application. • The microscopic mechanism underlying Cu-related emission has been provided.

  14. Gamma radiolysis of Cu(II) complex of metronidazole

    International Nuclear Information System (INIS)

    Mandal, P.C.; Bardhan, D.K.; Bhattacharyya, S.N.

    1990-01-01

    Aqueous solutions of Cu(II)Metronidazole (Cu(II)M) at neutral pH were irradiated with 60 Co γ-rays under different conditions of radiolysis. The radiolytic formation of HNO 2 and Cu(I) was followed. The radiolytic yields of chromophore loss of Cu(II)M were also determined under different conditions. The OH radicals attack the metal complex to give the OH adducts of the ligand at C 2 , C 4 , and C 5 either directly or through the formation of Cu(III) species. The C 5 -OH adduct, however, undergoes oxidative denitration and as a result the metal complex is decomposed. The OH adducts also undergo electron transfer to Cu(II) ion to give reduced complex. No denitration was observed due to the reaction of e eq - with the metal complex. On the other hand, the nitro group of the ligand in the complex undergoes successive 4-electron reduction to give hydroxylamino derivative. From the competition kinetics using t-butyl alcohol as the scavenger of OH in N 2 O saturated solution of the metal complex, the rate constant for the reaction of OH with complex was evaluated to be ca. 2.1x10 9 dm 3 mol -1 s -1 which is of the same order as that observed in the case of free metronidazole. (author)

  15. Changing the thickness of two layers: i-ZnO nanorods, p-Cu2O and its influence on the carriers transport mechanism of the p-Cu2O/i-ZnO nanorods/n-IGZO heterojunction.

    Science.gov (United States)

    Ke, Nguyen Huu; Trinh, Le Thi Tuyet; Phung, Pham Kim; Loan, Phan Thi Kieu; Tuan, Dao Anh; Truong, Nguyen Huu; Tran, Cao Vinh; Hung, Le Vu Tuan

    2016-01-01

    In this study, two layers: i-ZnO nanorods and p-Cu2O were fabricated by electrochemical deposition. The fabricating process was the initial formation of ZnO nanorods layer on the n-IGZO thin film which was prepared by sputtering method, then a p-Cu2O layer was deposited on top of rods to form the p-Cu2O/i-ZnO nanorods/n-ZnO heterojunction. The XRD, SEM, UV-VIS, I-V characteristics methods were used to define structure, optical and electrical properties of these heterojunction layers. The fabricating conditions and thickness of the Cu2O layers significantly affected to the formation, microstructure, electrical and optical properties of the junction. The length of i-ZnO nanorods layer in the structure of the heterojunction has strongly affected to the carriers transport mechanism and performance of this heterojunction.

  16. Chemical-bath ZnO buffer layer for CuInS{sub 2} thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ennaoui, A.; Weber, M.; Scheer, R.; Lewerenz, H.J. [Hahn-Meitner-Institut, Abt. Grenzflaechen, Bereich Physikalische Chemie, Glienicker Strasse 100, D-14109 Berlin (Germany)

    1998-07-13

    ZnO buffer layers were grown by a chemical-bath deposition (CBD) in order to improve the interface quality in p-CuInS{sub 2} based solar cells, to improve the light transmission in the blue wavelength region, but also as an alternative to eliminate the toxic cadmium. The process consists of immersion of different substrates (glass, CIS) in a dilute solution of tetraamminezinc II, [Zn(NH{sub 2}){sub 4}]{sup 2+}, complex at 60-95C. During the growth process, a homogeneous growth mechanism which proceeds by the sedimentation of a mixture of ZnO and Zn(OH){sub 2} clusters formed in solution, competes with the heterogeneous growth mechanism. The mechanism consists of specific adsorption of a complex Zn(II) followed by a chemical reaction. The last process of growth results in thin, hard, adherent and specularly reflecting films. The characterization of the deposited CBD-ZnO layers was performed by X-ray diffraction (XRD), optical transmittance, scanning electron microscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The as-deposited films on glass show hexagonal zincite structure with two preferred orientations (1 0 0) and (1 0 1). High optical transmittance up to 80% in the near-infrared and part of the visible region was observed. The low growth rate of the films on CIS suggests an atomic layer-by-layer growth process.The device parameters and performance are compared to heterojunction with a standard CdS buffer layer

  17. A chemosensor showing discriminating fluorescent response for highly selective and nanomolar detection of Cu²⁺ and Zn²⁺ and its application in molecular logic gate.

    Science.gov (United States)

    Fegade, Umesh A; Sahoo, Suban K; Singh, Amanpreet; Singh, Narinder; Attarde, Sanjay B; Kuwar, Anil S

    2015-05-04

    A fluorescent based receptor (4Z)-4-(4-diethylamino)-2-hydroxybenzylidene amino)-1,2dihydro-1,5-dimethyl-2-phenylpyrazol-3-one (receptor 3) was developed for the highly selective and sensitive detection of Cu(2+) and Zn(2+) in semi-aqueous system. The fluorescence of receptor 3 was enhanced and quenched, respectively, with the addition of Zn(2+) and Cu(2+) ions over other surveyed cations. The receptor formed host-guest complexes in 1:1 stoichiometry with the detection limit of 5 nM and 15 nM for Cu(2+) and Zn(2+) ions, respectively. Further, we have effectively utilized the two metal ions (Cu(2+) and Zn(2+)) as chemical inputs for the manufacture of INHIBIT type logic gate at molecular level using the fluorescence responses of receptor 3 at 450 nm. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Low Cycle Mechanical and Fatigue Properties of AlZnMgCu Alloy

    Directory of Open Access Journals (Sweden)

    Pysz S.

    2016-03-01

    Full Text Available The article presents the analysis of properties of the high-strength AlZnMgCu (abbr AlZn aluminium alloy and estimates possibilities of its application for responsible structures with reduced weight as an alternative to iron alloy castings. The aim of the conducted studies was to develop and select the best heat treatment regime for a 7xx casting alloy based on high-strength materials for plastic working from the 7xxx series. For analysis, wrought AlZnMgCu alloy (7075 was selected. Its potential of the estimated as-cast mechanical properties indicates a broad spectrum of possible applications for automotive parts and in the armaments industry. The resulting tensile and fatigue properties support the thesis adopted, while the design works further confirm these assumptions.

  19. Directional solidification of Zn-Al-Cu eutectic alloy by the vertical Bridgman method

    Directory of Open Access Journals (Sweden)

    Büyük U.

    2015-01-01

    Full Text Available In the present work, the effect of growth rate and temperature gradient on microstructure and mechanical properties of Zn-7wt.%Al-4wt.%Cu eutectic alloy has been investigated. Alloys prepared under steady-state conditions by vacuumed hot filing furnace. Then, the alloys were directionally solidified upward with different growth rates (V=11.62-230.77 mm/s at a constant temperature gradient (G=7.17 K/mm and with different temperature gradients (G=7.17-11.04 K/mm at a constant growth rate (V=11.62 mm/s by a Bridgman furnace. The microstructures were observed to be lamellae of Zn, Al and broken lamellae CuZn4 phases from quenched samples. The values of eutectic spacing, microhardness and ultimate tensile strength of alloys were measured. The dependency of the microstructure and mechanical properties on growth rate and temperature gradient were investigated using regression analysis.

  20. Transparent Cu4O3/ZnO heterojunction photoelectric devices

    Science.gov (United States)

    Kim, Hong-Sik; Yadav, Pankaj; Patel, Malkeshkumar; Kim, Joondong; Pandey, Kavita; Lim, Donggun; Jeong, Chaehwan

    2017-12-01

    The present article reports the development of flexible, self-biased, broadband, high speed and transparent heterojunction photodiode, which is essentially important for the next generation electronic devices. We grow semitransparent p-type Cu4O3 using the reactive sputtering method at room temperature. The structural and optical properties of the Cu4O3 film were investigated by using the X-ray diffraction and UV-visible spectroscopy, respectively. The p-Cu4O3/n-ZnO heterojunction diode under dark condition yields rectification behavior with an extremely low saturation current value of 1.8 × 10-10 A and a zero bias photocurrent under illumination condition. The transparent p-Cu4O3/n-ZnO heterojunction photodetector can be operated without an external bias, due to the light-induced voltage production. The metal oxide heterojunction based on Cu4O3/ZnO would provide a route for the transparent and flexible photoelectric devices, including photodetectors and photovoltaics.

  1. FOR CU-DOPED ZnS 'ALLOY

    African Journals Online (AJOL)

    2005-01-20

    Jan 20, 2005 ... electron transport property of thin films. may be characterized by the conductivity of the ... 3H20 were prepared and added drop by drop' to. 100ml of ZnS .... higher temperatures there is sufficient thermal activation fo~. I some electrons to .... telluride film on crystalline silicon, J. Appl. Phys. 54 (3): 1383-1389.

  2. Determination of Cu/Zn and Fe in human serum of patients with sickle cell anemia using radiation synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Canellas, C.G.L. [Nuclear Instrumentation Laboratory, COPPE/UFRJ, P.O. Box 68509, 21.941-972 Rio de Janeiro (Brazil); Carvalho, S.M.F. [State Institute of Hematology Arthur de Siqueira Cavalcanti, 20.211-030 Rio de Janeiro (Brazil); Anjos, M.J. [Nuclear Instrumentation Laboratory, COPPE/UFRJ, P.O. Box 68509, 21.941-972 Rio de Janeiro (Brazil); Physics Institute, State University of Rio de Janeiro, 20.559-900 Rio de Janeiro (Brazil); Lopes, R.T., E-mail: ricardo@lin.ufrj.br [Nuclear Instrumentation Laboratory, COPPE/UFRJ, P.O. Box 68509, 21.941-972 Rio de Janeiro (Brazil)

    2012-07-15

    In this work we analyzed serum samples from patients with Sickle Cell Anemia (SCA) using Total Reflection X-Ray Fluorescence using Synchrotron Radiation (SRTXRF). The SRTXRF measurements were performed at the X-Ray Fluorescence Beamline at the Brazilian National Synchrotron Light Laboratory (LNLS). We studied forty-three patients aged 18-50 suffering from SCA and sixty healthy volunteers aged 18-60. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Moreover, there are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. The concentrations of Fe and Cu in the serum samples of patients with SCA were larger, 120% and 20%, respectively, when compared with the CG. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples from patients suffering from SCA than from the CG. Therefore, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. - Highlights: Black-Right-Pointing-Pointer Serum samples from patients with Sickle Cell Anemia (SCA) were analyzed by SRTXRF. Black-Right-Pointing-Pointer It was possible to determine the concentrations of the P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Black-Right-Pointing-Pointer There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA process. Black-Right-Pointing-Pointer The results indicate that the Cu/Zn ratio can be used as an adjuvant index for diagnosis of SCA.

  3. Determination of Cu/Zn and Fe in human serum of patients with sickle cell anemia using radiation synchrotron

    International Nuclear Information System (INIS)

    Canellas, C.G.L.; Carvalho, S.M.F.; Anjos, M.J.; Lopes, R.T.

    2012-01-01

    In this work we analyzed serum samples from patients with Sickle Cell Anemia (SCA) using Total Reflection X-Ray Fluorescence using Synchrotron Radiation (SRTXRF). The SRTXRF measurements were performed at the X-Ray Fluorescence Beamline at the Brazilian National Synchrotron Light Laboratory (LNLS). We studied forty-three patients aged 18–50 suffering from SCA and sixty healthy volunteers aged 18–60. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Moreover, there are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. The concentrations of Fe and Cu in the serum samples of patients with SCA were larger, 120% and 20%, respectively, when compared with the CG. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples from patients suffering from SCA than from the CG. Therefore, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. - Highlights: ► Serum samples from patients with Sickle Cell Anemia (SCA) were analyzed by SRTXRF. ► It was possible to determine the concentrations of the P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. ► There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA process. ► The results indicate that the Cu/Zn ratio can be used as an adjuvant index for diagnosis of SCA.

  4. Comparative Toxicity of Nanoparticulate CuO and ZnO to Soil Bacterial Communities

    Science.gov (United States)

    Rousk, Johannes; Ackermann, Kathrin; Curling, Simon F.; Jones, Davey L.

    2012-01-01

    The increasing industrial application of metal oxide Engineered Nano-Particles (ENPs) is likely to increase their environmental release to soils. While the potential of metal oxide ENPs as environmental toxicants has been shown, lack of suitable control treatments have compromised the power of many previous assessments. We evaluated the ecotoxicity of ENP (nano) forms of Zn and Cu oxides in two different soils by measuring their ability to inhibit bacterial growth. We could show a direct acute toxicity of nano-CuO acting on soil bacteria while the macroparticulate (bulk) form of CuO was not toxic. In comparison, CuSO4 was more toxic than either oxide form. Unlike Cu, all forms of Zn were toxic to soil bacteria, and the bulk-ZnO was more toxic than the nano-ZnO. The ZnSO4 addition was not consistently more toxic than the oxide forms. Consistently, we found a tight link between the dissolved concentration of metal in solution and the inhibition of bacterial growth. The inconsistent toxicological response between soils could be explained by different resulting concentrations of metals in soil solution. Our findings suggested that the principal mechanism of toxicity was dissolution of metal oxides and sulphates into a metal ion form known to be highly toxic to bacteria, and not a direct effect of nano-sized particles acting on bacteria. We propose that integrated efforts toward directly assessing bioavailable metal concentrations are more valuable than spending resources to reassess ecotoxicology of ENPs separately from general metal toxicity. PMID:22479561

  5. Bioremediation of Zn, Cu, Mg and Pb in Fresh Domestic Sewage by Brevibacterium sp

    International Nuclear Information System (INIS)

    Ojoawo, S. O.; Rao, C. V.; Goveas, L. C.

    2016-01-01

    The study applied an isolated Brevibacterium sp. (MTCC 10313) for bioremediation of Zn, Cu, Mg and Pb in domestic sewage. Batch culture experiments were performed on both the fresh and stale sewage samples with glucose supplementation of 1-8g/l. Nutrient broth medium was prepared, sterilized and p H adjusted to 6.5-6.8. 1% of the Brevibacteria sp. stock was inoculated into the broth and maintained at 370C for 24 hours in shaker incubator at 120 rpm. Another 1% of fresh grown sub-culture of broth was inoculated into supplemented and sterilized samples. Optical Density was taken at 600nm, growth monitored over 12 days, cultured samples denatured with TCA and centrifuged, supernatants filtered and analyzed with AAS, Settled pellets oven dried, subjected to SEM analysis for morphology and constituents determination. Fresh sewage samples permitted bacterial growth and facilitated bioremediation of Zn, Cu and Mg through metal uptake and bioabsoption by Brevibacteria sp. This effectively reduced concentration of heavy metals, with treatment efficiency order Cu>Zn>Mg, and respective removal percentages of 77, 63 and 55. The optimum glucose concentration for effective bioremediation found as 2g/l for Zn and Cu, and 8g/l for Mg. Pb was resistant to bioremediation with Brevibacteria sp. Stale sewage produced inhibitory substances preventing adequate growth of bacterium with no bioremediation. Bioremediation with Brevibacteria sp. is found effective in removal of micro-units of Zn, Cu and Mg from domestic sewage. As a readily available low-cost agent, it is recommended for large- scale application on those metals while Pb should be further subjected to advanced treatments.

  6. Microstructural characteristics and aging response of Zn-containing Al-Mg-Si-Cu alloy

    Science.gov (United States)

    Cai, Yuan-hua; Wang, Cong; Zhang, Ji-shan

    2013-07-01

    Al-Mg-Si-Cu alloys with and without Zn addition were fabricated by conventional ingot metallurgy method. The microstructures and properties were investigated using optical microscopy (OM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), tensile test, hardness test, and electrical conductivity measurement. It is found that the as-cast Al-Mg-Si-Cu-Zn alloy is composed of coarse dendritic grains, long needle-like β/δ-AlFeSi white intermetallics, and Chinese script-like α-AlFeSi compounds. During high temperature homogenization treatment, only harmful needle-like β-AlFeSi phase undergoes fragmentation and spheroidizing at its tips, and the destructive needle-like δ-phase does not show any morphological and size changes. Phase transitions from β-AlFeSi to α-AlFeSi and from δ-AlFeSi to β-AlFeSi are also not found. Zn addition improves the aging hardening response during the former aging stage and postpones the peak-aged hardness to a long aging time. In T4 condition, Zn addition does not obviously increase the yield strength and decrease the elongation, but it markedly improves paint-bake hardening response during paint-bake cycle. The addition of 0.5wt% Zn can lead to an increment of 99 MPa in yield strength compared with the value of 69 MPa for the alloy without Zn after paint-bake cycle.

  7. The influence of precursor Cu content and two-stage processing conditions on the microstructure of Cu{sub 2}ZnSnSe{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Márquez-Prieto, J., E-mail: jose.prieto@northumbria.ac.uk [Northumbria Photovoltaic Application Centre, Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom); Ren, Y. [Ångström Solar Center, Solid State Electronics, Uppsala University, Uppsala 751 21 (Sweden); Miles, R.W.; Pearsall, N.; Forbes, I. [Northumbria Photovoltaic Application Centre, Faculty of Engineering and Environment, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom)

    2015-05-01

    This paper reports the influence of processing temperature on the microstructure of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) absorber layers for temperatures between 380 and 550 °C produced using a 2-stage process. X-ray diffraction analysis showed the formation of Cu{sub 2}ZnSnSe{sub 4} over this temperatures range. The Williamson-Hall method was used for microstructural analysis of the CZTSe absorbers, and this showed a progressive decrease of the micro-strain of the CZTSe with increasing selenisation temperature. The influence of precursor Cu content on the microstructure of the CZTSe was also studied. An increase of Cu content in the precursor is correlated to an increase in grain size and a decrease in micro-strain. Raman measurements show an asymmetrical broadening towards lower energies of the main 197 cm{sup −1} mode for Cu-poor compositions. This study provides an insight into the dependency of the crystallinity of CZTSe on composition and synthesis temperature. - Highlights: • We fabricate Cu{sub 2}ZnSnSe{sub 4} thin films by sputtering and post-reactive annealing. • The micro-strain of Cu{sub 2}ZnSnSe{sub 4} increases when Cu content decreases. • The micro-strain of Cu{sub 2}ZnSnSe{sub 4} decreases with increasing processing temperature. • The defect concentration of Cu{sub 2}ZnSnSe{sub 4} increases when Cu content decreases.

  8. Intermixing at the heterointerface between ZnS Zn S,O bilayer buffer and CuInS2 thin film solar cell absorber

    OpenAIRE

    Bär, M.; Ennaoui, A.; Klaer, J.; Kropp, T.; S ez Araoz, R.; Lehmann, S.; Grimm, A.; Lauermann, I.; Loreck, Ch.; Sokoll, St.; Schock, H. W.; Fischer, Ch. H.; Lux Steiner, M.C.; Jung, Ch

    2006-01-01

    The application of Zn compounds as buffer layers was recently extended to wide gap CuInS2 CIS based thin film solar cells. Using a new chemical deposition route for the buffer preparation aiming at the deposition of a single layer, nominal ZnS buffer without the need for any toxic reactants such as, e.g. hydrazine has helped to achieve a similar efficiency as respective CdS buffered reference devices. After identifying the deposited Zn compound, as ZnS Zn S,O bi layer buffer in former in...

  9. Cu{sub 2}ZnSnS{sub 4} solar cells prepared by sulfurization of sputtered ZnS/Sn/CuS precursors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhi-Shan; Wang, Shu-Rong, E-mail: shrw88@aliyun.com; Jiang, Zhi; Yang, Min; Lu, Yi-Lei; Liu, Si-Jia; Zhao, Qi-Chen; Hao, Rui-Ting

    2016-12-01

    Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films were grown on Mo-coated Soda-lime-glass (SLG) substrates by sulfurization of sputtered ZnS/Sn/CuS precursors at different temperatures i.e. 560 °C, 580 °C and 600 °C. The effects of sulfurization temperature on the quality of CZTS thin films and solar cells were investigated. The crystal structure, surface morphology, chemical composition, phase purity and surface roughness of CZTS thin films fabricated at different sulfurization temperatures were characterized by X Ray Diffraction (XRD), scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS), Raman spectroscopy and atomic force microscope (AFM), respectively. The results show that all CZTS thin films exhibit a polycrystalline kesterite structure and preferred (112) orientation. For the sulfurization temperature of 580 °C, the obtained CZTS thin films are dense and flat with larger grain size. Meanwhile composition studying indicates that the fabricated CZTS with single phase is copper poor and zinc rich. Furthermore, the surface roughness of CZTS film is the lowest. Finally, the CZTS solar cells with the structure of SLG/Mo/CZTS/CdS/i-ZnO/ITO/Al were fabricated and demonstrated the best power conversion efficiency of 3.59% when used sulfurization temperature was 580 °C.

  10. Cofiring behavior and interfacial structure of NiCuZn ferrite/PMN ferroelectrics composites for multilayer LC filters

    International Nuclear Information System (INIS)

    Miao Chunlin; Zhou Ji; Cui Xuemin; Wang Xiaohui; Yue Zhenxing; Li Longtu

    2006-01-01

    The cofiring behavior, interfacial structure and cofiring migration between NiCuZn ferrite and lead magnesium niobate (PMN)-based relaxor ferroelectric materials were investigated via thermomechanical analyzer (TMA), X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Mismatched sintering shrinkage between NiCuZn ferrite and PMN was modified by adding an appropriate amount of sintering aids, Bi 2 O 3 , into NiCuZn ferrite. Pyrochlore phase appeared in the mixture of NiCuZn ferrite and PMN, which is detrimental to the final electric properties of LC filters. EDS results indicated that the interdiffusion at the heterogeneous interfaces in the composites, such as Fe, Pb, Zn, existed which can strengthen combinations between ferrite layers and ferroelectrics layers

  11. Defect complexes formed with Ag atoms in CDTE, ZnTe, and ZnSe

    CERN Document Server

    Wolf, H; Ostheimer, V; Hamann, J; Lany, S; Wichert, T

    2000-01-01

    Using the radioactive acceptor $^{111}\\!$Ag for perturbed $\\gamma$-$\\gamma$-angular correlation (PAC) spectroscopy for the first time, defect complexes formed with Ag are investigated in the II-VI semiconductors CdTe, ZnTe and ZnSe. The donors In, Br and the Te-vacancy were found to passivate Ag acceptors in CdTe via pair formation, which was also observed in In-doped ZnTe. In undoped or Sb-doped CdTe and in undoped ZnSe, the PAC experiments indicate the compensation of Ag acceptors by the formation of double broken bond centres, which are characterised by an electric field gradient with an asymmetry parameter close to h = 1. Additionally, a very large electric field gradient was observed in CdTe, which is possibly connected with residual impurities.

  12. Predictive calculation of phase formation in Al-rich Al-Zn-Mg-Cu-Sc-Zr alloys using a thermodynamic Mg-alloy database

    International Nuclear Information System (INIS)

    Groebner, J.; Rokhlin, L.L.; Dobatkina, T.V.; Schmid-Fetzer, R.

    2007-01-01

    Three series of Al-rich alloys in the system Al-Zn-Mg-Cu-Sc-Zr and the subsystems Al-Zn-Mg-Cu-Sc and Al-Zn-Mg-Sc were studied by thermodynamic calculations. Phase formation was compared with experimental data obtained by DTA and microstructural analysis. Calculated phase diagrams, phase amount charts and enthalpy charts together with non-equilibrium calculations under Scheil conditions reveal significant details of the complex phase formation. This enables consistent and correct interpretation of thermal analysis data. Especially the interpretation of liquidus temperature and primary phase is prone to be wrong without using this tool of computational thermodynamics. All data are predictions from a thermodynamic database developed for Mg-alloys and not a specialized Al-alloy database. That provides support for a reasonable application of this database for advanced Mg-alloys beyond the conventional composition ranges

  13. Predictive calculation of phase formation in Al-rich Al-Zn-Mg-Cu-Sc-Zr alloys using a thermodynamic Mg-alloy database

    Energy Technology Data Exchange (ETDEWEB)

    Groebner, J. [Institute of Metallurgy, Clausthal University of Technology, Robert-Koch Strasse 42, D-38678 Clausthal-Zellerfeld (Germany); Rokhlin, L.L. [Baikov Institute of Metallurgy and Materials Science, Leninsky prosp. 49, 119991 GSP-1, Moscow (Russian Federation); Dobatkina, T.V. [Baikov Institute of Metallurgy and Materials Science, Leninsky prosp. 49, 119991 GSP-1, Moscow (Russian Federation); Schmid-Fetzer, R. [Institute of Metallurgy, Clausthal University of Technology, Robert-Koch Strasse 42, D-38678 Clausthal-Zellerfeld (Germany)]. E-mail: schmid-fetzer@tu-clausthal.de

    2007-05-16

    Three series of Al-rich alloys in the system Al-Zn-Mg-Cu-Sc-Zr and the subsystems Al-Zn-Mg-Cu-Sc and Al-Zn-Mg-Sc were studied by thermodynamic calculations. Phase formation was compared with experimental data obtained by DTA and microstructural analysis. Calculated phase diagrams, phase amount charts and enthalpy charts together with non-equilibrium calculations under Scheil conditions reveal significant details of the complex phase formation. This enables consistent and correct interpretation of thermal analysis data. Especially the interpretation of liquidus temperature and primary phase is prone to be wrong without using this tool of computational thermodynamics. All data are predictions from a thermodynamic database developed for Mg-alloys and not a specialized Al-alloy database. That provides support for a reasonable application of this database for advanced Mg-alloys beyond the conventional composition ranges.

  14. [Changes in bio-availability of immobilized Cu and Zn bound to phosphate in contaminated soils with different nutrient addition].

    Science.gov (United States)

    Xu, Ming-Gang; Zhang, Qian; Sun, Nan; Shen, Hua-Ping; Zhang, Wen-Ju

    2009-07-15

    Bio-availability of Cu and Zn fixed by phosphate in contaminated soils with application of nutrients were measured by pot experiment. It was simulated for the third national standardization of copper and zinc polluted soils by adding copper and zinc nitrate into red and paddy soils, respectively and together. Phosphate amendment was added to the soils to fix Cu and Zn, then added KCl and NH4Cl or K2SO4 and (NH4)2SO4 fertilizers following to plant Ryegrass, which was harvested after 40 d. Available Cu/Zn content in soils and biomass, Cu/Zn content in the shoot of Ryegrass were determined. Results showed that, compared with no nutrient application, adding KCl and NH4 Cl/K2SO4 and (NH4)2SO4 to polluted red and paddy soils increased the available Cu and Zn content in red soil significantly. The increasing order was KCl and NH4 Cl > K2SO4 and (NH4)2SO4. Especially in single Zn polluted red soil, the available Zn content increased by 133.4% in maximum. Although adding K2SO4 and (NH4)2SO4 could promote the growth of Ryegrass on red soil, and the largest increasing was up to 22.2%, it increased Cu and Zn content in the shoot of Ryegrass for 21.5%-112.6% remarkably. These nutrient effects on available Cu and Zn were not significantly in paddy soil. It was suggested that application of nitrogen and potassium fertilizers to soils could change the bioavailability of Cu/Zn. So it is necessary to take full account of the nutrient influence to the heavy metal stability which fixed by phosphate in contaminated soils when consider contaminated soils remediation by fertilization.

  15. Toxicity of nanoparticles of CuO, ZnO and TiO2 to microalgae Pseudokirchneriella subcapitata.

    Science.gov (United States)

    Aruoja, Villem; Dubourguier, Henri-Charles; Kasemets, Kaja; Kahru, Anne

    2009-02-01

    Toxicities of ZnO, TiO2 and CuO nanoparticles to Pseudokirchneriella subcapitata were determined using OECD 201 algal growth inhibition test taking in account potential shading of light. The results showed that the shading effect by nanoparticles was negligible. ZnO nanoparticles were most toxic followed by nano CuO and nano TiO2. The toxicities of bulk and nano ZnO particles were both similar to that of ZnSO4 (72 h EC50 approximately 0.04 mg Zn/l). Thus, in this low concentration range the toxicity was attributed solely to solubilized Zn2+ ions. Bulk TiO2 (EC50=35.9 mg Ti/l) and bulk CuO (EC50=11.55 mg Cu/l) were less toxic than their nano formulations (EC50=5.83 mg Ti/l and 0.71 mg Cu/l). NOEC (no-observed-effect-concentrations) that may be used for risk assessment purposes for bulk and nano ZnO did not differ (approximately 0.02 mg Zn/l). NOEC for nano CuO was 0.42 mg Cu/l and for bulk CuO 8.03 mg Cu/l. For nano TiO2 the NOEC was 0.98 mg Ti/l and for bulk TiO2 10.1 mg Ti/l. Nano TiO2 formed characteristic aggregates entrapping algal cells that may contribute to the toxic effect of nano TiO2 to algae. At 72 h EC50 values of nano CuO and CuO, 25% of copper from nano CuO was bioavailable and only 0.18% of copper from bulk CuO. Thus, according to recombinant bacterial and yeast Cu-sensors, copper from nano CuO was 141-fold more bioavailable than from bulk CuO. Also, toxic effects of Cu oxides to algae were due to bioavailable copper ions. To our knowledge, this is one of the first systematic studies on effects of metal oxide nanoparticles on algal growth and the first describing toxic effects of nano CuO towards algae.

  16. Facile synthesis of ZnO/CuInS{sub 2} nanorod arrays for photocatalytic pollutants degradation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yawei [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic & Information Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Que, Wenxiu, E-mail: wxque@mail.xjtu.edu.cn [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic & Information Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Zhang, Xinyu [Frontier Institute of Science and Technology Jointly with College of Science, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Xing, Yonglei; Yin, Xingtian [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic & Information Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Du, Yaping, E-mail: ypdu2013@mail.xjtu.edu.cn [Frontier Institute of Science and Technology Jointly with College of Science, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China)

    2016-11-05

    Highlights: • Vertically-aligned ZnO nanorod arrays were synthesized by the hydrothermal process. • Monodisperse CuInS{sub 2} QDs were synthesized by the one-pot colloidal chemistry method. • ZnO/CuInS{sub 2} nanorod arrays films were fabricated by the EPD process. • The homogeneous CuInS{sub 2} loading was optimized by EPD duration. • The photoelectrochemical and photocatalytic activities of the ZnO/CuInS{sub 2} nanorod arrays films were discussed. - Abstract: Vertically-aligned ZnO nanorod arrays on a fluorine-doped tin oxide glass substrate were homogeneously coated with visible light active CuInS{sub 2} quantum dots by using a controllable electrophoretic deposition strategy. Compared with the pure ZnO nanorod arrays, the formation of high-quality ZnO/CuInS{sub 2} heterojunction with well-matched band energy alignment expanded the light absorption from ultraviolet to visible region and facilitated efficient charge separation and transportation, thus yielding remarkable enhanced photoelectrochemical performance and photocatalytic activities for methyl orange and 4-chlorophenol degradation. The ZnO/CuInS{sub 2} film with the deposition duration of 80 min showed the highest degradation rate and photocurrent density (0.95 mA/cm{sup 2}), which was almost 6.33 times higher than that of the pure ZnO nanorod arrays film. The CuInS{sub 2} QDs sensitized ZnO nanorod arrays film was proved to be a superior structure for photoelectrochemical and photocatalytic applications due to the optimized CuInS{sub 2} loading and well-maintained one-dimensional nanostructure.

  17. Synthesis and electrical characterization of vertically-aligned ZnO–CuO hybrid nanowire p–n junctions

    International Nuclear Information System (INIS)

    Pukird, Supakorn; Song, Wooseok; Noothongkaew, Suttinart; Kim, Seong Ku; Min, Bok Ki; Kim, Seong Jun; Kim, Ki Woong; Myung, Sung; An, Ki-Seok

    2015-01-01

    Highlights: • Vertically-aligned ZnO–CuO hybrid nanowire arrays were synthesized by a two-step thermal chemical vapor deposition process. • The diameter of parallel-connected ZnO and CuO NWs were estimated to be 146 ± 12 nm and 55 ± 11 nm, respectively, and the formation of high-quality hexagonal ZnO and monoclinic CuO NWs were observed. • Clear rectifying behavior related with thermionic emission of carriers and the presence of an electrical potential barrier between the ZnO and CuO NWs were observed. - Abstract: In order to form nanowire (NW)-based p–n junctions, vertically-aligned ZnO–CuO hybrid NW arrays were synthesized by a two-step thermal chemical vapor deposition process. The diameter of parallel-connected ZnO and CuO NWs were estimated to be 146 ± 12 nm and 55 ± 11 nm, respectively, as observed by scanning electron microscopy. Chemical and structural characterizations of ZnO–CuO hybrid NW arrays were performed using X-ray photoelectron spectroscopy and X-ray diffraction, resulting in the formation of high-quality hexagonal ZnO and monoclinic CuO NWs. The temperature dependence of I–V curves and impedance spectra suggested that clear rectifying behavior related with thermionic emission of carriers and the presence of an electrical potential barrier between the ZnO and CuO NWs

  18. In situ monitoring the growth of thin-film ZnS/Zn (S,O) bilayer on Cu-chalcopyrite for high performance thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saez-Araoz, R.; Abou-Ras, D. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Solar Energy Division, Glienicker Strasse 100, 14109 Berlin (Germany); Niesen, T.P. [AVANCIS GmbH and Co KG Otto-Hahn-Ring 6, 81739 Munich (Germany); Neisser, A.; Wilchelmi, K. [SULFURCELL Solartechnik GmbH Barbara-McClintock-Strasse 11, 12489 Berlin (Germany); Lux-Steiner, M.Ch. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Solar Energy Division, Glienicker Strasse 100, 14109 Berlin (Germany); Ennaoui, A. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Solar Energy Division, Glienicker Strasse 100, 14109 Berlin (Germany)], E-mail: ennaoui@helmholtz-berlin.de

    2009-02-02

    This paper highlights the crucial role that the control of the chemical bath deposition (CBD) process plays for buffer production of Cu-chalcopyrite solar-cell devices. ZnS/Zn (S,O) bilayer was deposited on CuInS{sub 2} (CIS) and Cu(In,Ga)(SSe){sub 2} (CIGSSe) and monitored using turbidity measurements of the solution. The results were correlated to the X-ray photoemission spectra of the samples obtained by interruption of the process at sequential stages. Two different feature regimes were distinguished: In the first stage, a heterogeneous reaction takes place on the absorber resulting in the formation of pure ZnS. The second stage of the process is homogeneous, and the in-situ turbidity measurement shows a loss in the transmission of light through the CBD solution. The measured ZnL3M45M45 Auger-peaks, during this second stage of the process, show a shift of the kinetic energy from pure ZnS to a solid-solution ZnS/ZnO ('Zn (S,O)') with decreasing amount of sulfur. These results are supported by the observations from Energy-filtered transmission electron microscopy. This paper also demonstrates that monitoring of the CBD process combined with the basic understanding using surface and interface analysis have contributed to improve the reproducibility and to enhance the photovoltaic performance of Cu-chalcopyrite thin-film solar modules.

  19. In situ monitoring the growth of thin-film ZnS/Zn (S,O) bilayer on Cu-chalcopyrite for high performance thin film solar cells

    International Nuclear Information System (INIS)

    Saez-Araoz, R.; Abou-Ras, D.; Niesen, T.P.; Neisser, A.; Wilchelmi, K.; Lux-Steiner, M.Ch.; Ennaoui, A.

    2009-01-01

    This paper highlights the crucial role that the control of the chemical bath deposition (CBD) process plays for buffer production of Cu-chalcopyrite solar-cell devices. ZnS/Zn (S,O) bilayer was deposited on CuInS 2 (CIS) and Cu(In,Ga)(SSe) 2 (CIGSSe) and monitored using turbidity measurements of the solution. The results were correlated to the X-ray photoemission spectra of the samples obtained by interruption of the process at sequential stages. Two different feature regimes were distinguished: In the first stage, a heterogeneous reaction takes place on the absorber resulting in the formation of pure ZnS. The second stage of the process is homogeneous, and the in-situ turbidity measurement shows a loss in the transmission of light through the CBD solution. The measured ZnL3M45M45 Auger-peaks, during this second stage of the process, show a shift of the kinetic energy from pure ZnS to a solid-solution ZnS/ZnO ('Zn (S,O)') with decreasing amount of sulfur. These results are supported by the observations from Energy-filtered transmission electron microscopy. This paper also demonstrates that monitoring of the CBD process combined with the basic understanding using surface and interface analysis have contributed to improve the reproducibility and to enhance the photovoltaic performance of Cu-chalcopyrite thin-film solar modules

  20. Adsorption of tetracycline on Fe (hydr)oxides: effects of pH and metal cation (Cu2+, Zn2+ and Al3+) addition in various molar ratios

    Science.gov (United States)

    Hsu, Liang-Ching; Liu, Yu-Ting; Syu, Chien-Hui; Huang, Mei-Hsia; Teah, Heng Yi

    2018-01-01

    Iron (Fe) (hydr)oxides control the mobility and bioavailability of tetracycline (TC) in waters and soils. Adsorption of TC on Fe (hydr)oxides is greatly affected by polyvalent metals; however, impacts of molar metal/TC ratios on TC adsorptive behaviours on Fe (hydr)oxides remain unclear. Results showed that maximum TC adsorption on ferrihydrite and goethite occurred at pH 5–6. Such TC adsorption was generally promoted by the addition of Cu2+, Zn2+ and Al3+. The greatest increase in TC adsorption was found in the system with molar Cu/TC ratio of 3 due to the formation of Fe hydr(oxide)–Cu–TC ternary complexes. Functional groups on TC that were responsible for the complexation with Cu2+shifted from phenolic diketone groups at Cu/TC molar ratio adsorption at a molar Al/TC ratio of 1. However, TC adsorption decreased for Al/TC molar ratio > 1 as excess Al3+ led to the competitive adsorption with Al/TC complexes. For the Zn2+ addition, no significant correlation was found between TC adsorption capacity and molar Zn/TC ratios. PMID:29657795

  1. Polarizable molecular mechanics studies of Cu(I)/Zn(II) superoxide dismutase: bimetallic binding site and structured waters.

    Science.gov (United States)

    Gresh, Nohad; El Hage, Krystel; Perahia, David; Piquemal, Jean-Philip; Berthomieu, Catherine; Berthomieu, Dorothée

    2014-11-05

    The existence of a network of structured waters in the vicinity of the bimetallic site of Cu/Zn-superoxide dismutase (SOD) has been inferred from high-resolution X-ray crystallography. Long-duration molecular dynamics (MD) simulations could enable to quantify the lifetimes and possible interchanges of these waters between themselves as well as with a ligand diffusing toward the bimetallic site. The presence of several charged or polar ligands makes it necessary to resort to second-generation polarizable potentials. As a first step toward such simulations, we benchmark in this article the accuracy of one such potential, sum of interactions between fragments Ab initio computed (SIBFA), by comparisons with quantum mechanics (QM) computations. We first consider the bimetallic binding site of a Cu/Zn-SOD, in which three histidines and a water molecule are bound to Cu(I) and three histidines and one aspartate are bound to Zn(II). The comparisons are made for different His6 complexes with either one or both cations, and either with or without Asp and water. The total net charges vary from zero to three. We subsequently perform preliminary short-duration MD simulations of 296 waters solvating Cu/Zn-SOD. Six representative geometries are selected and energy-minimized. Single-point SIBFA and QM computations are then performed in parallel on model binding sites extracted from these six structures, each of which totals 301 atoms including the closest 28 waters from the Cu metal site. The ranking of their relative stabilities as given by SIBFA is identical to the QM one, and the relative energy differences by both approaches are fully consistent. In addition, the lowest-energy structure, from SIBFA and QM, has a close overlap with the crystallographic one. The SIBFA calculations enable to quantify the impact of polarization and charge transfer in the ranking of the six structures. Five structural waters, which connect Arg141 and Glu131, are endowed with very high dipole moments

  2. In-situ XRD study of alloyed Cu2ZnSnSe4-CuInSe2 thin films for solar cells

    International Nuclear Information System (INIS)

    Hartnauer, Stefan; Wägele, Leonard A.; Jarzembowski, Enrico; Scheer, Roland

    2015-01-01

    We investigate the growth of Cu 2 ZnSnSe 4 -CuInSe 2 (CZTISe) thin films using a 2-stage (Cu-rich/Cu-free) co-evaporation process under simultaneous application of in-situ angle dispersive X-ray diffraction (XRD). In-situ XRD allows monitoring the phase formation during preparation. A variation of the content of indium in CZTISe leads to a change in the lattice constant. Single phase CZTISe is formed in a wide range, while at high In contents a phase separation is detected. Because of different thermal expansion coefficients, the X-ray diffraction peaks of ZnSe and CZTISe can be distinguished at elevated substrate temperatures. The formation of ZnSe appears to be inhibited even for low indium content. In-situ XRD shows no detectable sign for the formation of ZnSe. First solar cells of CZTISe have been prepared and show comparable performance to CZTSe. - Highlights: • In-situ XRD study of two-stage co-evaporated Cu 2 ZnSnSe 4 -CuInSe 2 alloyed thin films. • No detection of ZnSe with in-situ XRD due to Indium incorporation • Comparable efficiency of alloyed solar cells

  3. Half-metallic ferromagnetism in Cu-doped zinc-blende ZnO from first principles study

    International Nuclear Information System (INIS)

    Li, X.F.; Zhang, J.; Xu, B.; Yao, K.L.

    2012-01-01

    Electronic structures and magnetism of Cu-doped zinc-blende ZnO have been investigated by the first-principle method based on density functional theory (DFT). The results show that Cu can induce stable ferromagnetic ground state. The magnetic moment of supercell including single Cu atom is 1.0 μ B . Electronic structure shows that Cu-doped zinc-blende ZnO is a p-type half-metallic ferromagnet. The half-metal property is mainly attribute to the crystal field splitting of Cu 3d orbital, and the ferromagnetism is dominated by the hole-mediated double exchange mechanism. Therefore, Cu-doped zinc-blende ZnO should be useful in semiconductor spintronics and other applications. - Highlights: → Magnetism of Cu-doped zinc-blende ZnO. → Cu-doped zinc-blende ZnO shows interesting half-metal character. → Total energies calculations reveal that Cu can induce ferromagnetic ground state. → Ferromagnetism dominated by the hole-mediated double exchange mechanism.

  4. Trace amounts of Cu{sup 2+} ions influence ROS production and cytotoxicity of ZnO quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Moussa, Hatem [CNRS and Université de Lorraine, Laboratoire Réactions et Génie des Procédés (LRGP), CNRS UMR 7274, 1 rue Grandville, 54001 Nancy (France); Laboratoire de Biosurveillance de l' Environnement, Université de Carthage, Faculté des Sciences de Bizerte, 7021 Jarzouna, Bizerte (Tunisia); Merlin, Christophe [CNRS and Université de Lorraine, Laboratoire de Chimie Physique et Microbiologie pour l' Environnement (LCPME), CNRS UMR 7564, 15 Avenue du Charmois, 54500 Vandoeuvre-lès-Nancy (France); Dezanet, Clément [CNRS and Université de Lorraine, Laboratoire Réactions et Génie des Procédés (LRGP), CNRS UMR 7274, 1 rue Grandville, 54001 Nancy (France); Balan, Lavinia [Institut de Science des Matériaux de Mulhouse (IS2M), CNRS UMR 7361, 15 rue Jean Starcky, 68093 Mulhouse (France); Medjahdi, Ghouti [CNRS and Université de Lorraine, Institut Jean Lamour (IJL), UMR CNRS 7198, BP 70239, 54506 Vandoeuvre-lès-Nancy Cedex (France); Ben-Attia, Mossadok [Laboratoire de Biosurveillance de l' Environnement, Université de Carthage, Faculté des Sciences de Bizerte, 7021 Jarzouna, Bizerte (Tunisia); and others

    2016-03-05

    Highlights: • Chemisorbed Cu{sup 2+} ions on ZnO QDs enhance ROS production. • A mechanism combining excited electrons and holes and Fenton reactions is proposed. • ZnO@APTMS/Cu QDs were found to be the most deleterious to E. coli cells. - Abstract: 3-Aminopropyltrimethoxysilane (APTMS) was used as ligand to prepare ZnO@APTMS, Cu{sup 2+}-doped ZnO (ZnO:Cu@APTMS) and ZnO quantum dots (QDs) with chemisorbed Cu{sup 2+} ions at their surface (ZnO@APTMS/Cu). The dots have a diameter of ca. 5 nm and their crystalline and phase purities and composition were established by X-ray diffraction, transmission electron microscopy, UV-visible and fluorescence spectroscopies and by X-ray photoelectron spectroscopy. The effect of Cu{sup 2+} location on the ability of the QDs to generate reactive oxygen species (ROS) under light irradiation was investigated. Results obtained demonstrate that all dots are able to produce ROS (·OH, O{sub 2}·{sup −}, H{sub 2}O{sub 2} and {sup 1}O{sub 2}) and that ZnO@APTMS/Cu QDs generate more ·OH and O{sub 2}·{sup −} radicals and H{sub 2}O{sub 2} than ZnO@APTMS and ZnO:Cu@APTMS QDs probably via mechanisms associating photo-induced charge carriers and Fenton reactions. In cytotoxicity experiments conducted in the dark or under light exposure, ZnO@APTMS/Cu QDs appeared slightly more deleterious to Escherichia coli cells than the two other QDs, therefore pointing out the importance of the presence of Cu{sup 2+} ions at the periphery of the nanocrystals. On the other hand, with the lack of photo-induced toxicity, it can be inferred that ROS production cannot explain the cytotoxicity associated to the QDs. Our study demonstrates that both the production of ROS from ZnO QDs and their toxicity may be enhanced by chemisorbed Cu{sup 2+} ions, which could be useful for medical or photocatalytic applications.

  5. Effects of boron and aging on mechanical properties and martensitic temperatures in Cu-Zn-Al shape-memory alloys

    International Nuclear Information System (INIS)

    Han, Y.S.; Kim, Y.G.

    1987-01-01

    This work is concerned with the effects of added boron (0.1 w/o) on mechanical properties and martensitic transformation temperatures (Ms) of the Cu - 14.0 Zn - 8.5. Al shape memory alloy. The composition was designed to have Ms temperature in the vicinity of 100 0 C. The influence of applying step quenching on the variation in Ms temperatures has been studied in boron-free Cu - 14.0 Zn - 8.5 Al and boron-containing Cu - 14.0 Zn 8.5 Al - 0.1 B alloys. Aging kinetics and transformation temperatures have been determined by electrical resistivity measurements

  6. Synthesis and characterization of Ce, Cu co-doped ZnS nanoparticles

    International Nuclear Information System (INIS)

    Harish, G.S.; Sreedhara Reddy, P.

    2015-01-01

    Ce, Cu co-doped ZnS nanoparticles were prepared at room temperature using a chemical co-precipitation method. The prepared nanoparticles were characterized by X- ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive analysis of X-rays (EDAX), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) and high resolution Raman spectroscopic techniques. Transmission electron microscopy (TEM) and X-ray diffraction studies showed that the diameter of the particles was around 2–3 nm. Broadened XRD peaks revealed the formation of nanoparticles with a face centered cubic (fcc) structure. DRS studies confirmed that the band gap increased with an increase in the dopant concentration. The Raman spectra of undoped and Ce, Cu ions co-doped ZnS nanoparticles showed longitudinal optical mode and transverse optical mode. Compared with the Raman modes (276 and 351 cm −1 ) of undoped ZnS nanoparticles, the Raman modes of Ce, Cu co- doped ZnS nanoparticles were slightly shifted towards lower frequency. PL spectra of the samples showed remarkable enhancement in the intensity upon doping

  7. Estimated daily intake of Fe, Cu, Ca and Zn through common cereals in Tehran, Iran.

    Science.gov (United States)

    Kashian, S; Fathivand, A A

    2015-06-01

    This paper presents the findings of study undertaken to estimate the dietary intake of iron (Fe), copper (Cu), calcium (Ca) and zinc (Zn) through common cereals in Tehran, Iran. 100 samples of rice, wheat and barley were collected from various brands between August and October 2013. The samples were analyzed performing instrumental neutron activation analysis (INAA). The dietary intake for adults was estimated by a total cereal study. Calculations were carried out on the basis of the reported adults' average food consumption rate data. The total daily intake estimated in mgd(-1) for Tehran population were 3.6 (Fe), 10.2 (Zn), 0.3 (Cu) and 234.5 (Ca). Wheat showed the highest contribution to Zn, Cu and Ca intakes. Furthermore, intakes were compared with recommended dietary allowance (RDA). Zn total intake (10.2mgd(-1)) was comparable with RDA values for males (11mgd(-1)) and was higher than recommended value for females (8mgd(-1)). The intakes of other studied elements were below the respective RDAs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Preparation and characterization of co-evaporated Cu{sub 2}ZnGeSe{sub 4} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Uday Bhaskar, P.; Suresh Babu, G.; Kishore Kumar, Y.B.; Sundara Raja, V., E-mail: sundararajav@rediffmail.com

    2013-05-01

    Cu{sub 2}ZnGeSe{sub 4} (CZGSe), a member of Cu{sub 2}–II–IV–VI{sub 4} family, is a promising material for solar cell absorber layer in thin film heterojunction solar cells like Cu{sub 2}ZnSnS{sub 4} and Cu{sub 2}ZnSnSe{sub 4} which have been explored in recent years as alternate to CuInGaSe{sub 2} solar cells. The effect of substrate temperature (523 K–723 K) on the growth of CZGSe films is investigated by studying their structural, morphological and optical properties. Raman spectroscopy studies have been done to identify the phases in addition to X-ray diffraction studies. CZGSe films deposited at different substrate temperatures and annealed at 723 K in selenium atmosphere are Cu-rich and Ge-poor and contained secondary phases Cu{sub (2−x)}Se and ZnSe. CZGSe films obtained by reducing the starting Cu mass by 10% were found to be single phase with stannite structure, the lattice parameters being a = 0.563 nm, c = 1.101 nm. The direct optical band gap of CZGSe films is found to be 1.63 eV which is close to ideal band gap of 1.50 eV for the highest photovoltaic conversion efficiency. The films are found to be p-type. - Highlights: • Synthesis of Cu{sub 2}ZnGeSe{sub 4} films for solar cell absorber layer • Effect of substrate temperature on the growth of co-evaporated Cu{sub 2}ZnGeSe{sub 4} films • X-ray diffraction, Raman and morphological studies of Cu{sub 2}ZnGeSe{sub 4} thin films.

  9. Structure and electronic properties of grain boundaries in earth-abundant photovoltaic absorber Cu2ZnSnSe4.

    Science.gov (United States)

    Li, Junwen; Mitzi, David B; Shenoy, Vivek B

    2011-11-22

    We have studied the atomic and electronic structure of Cu(2)ZnSnSe(4) and CuInSe(2) grain boundaries using first-principles calculations. We find that the constituent atoms at the grain boundary in Cu(2)ZnSnSe(4) create localized defect states that promote the recombination of photon-excited electron and hole carriers. In distinct contrast, significantly lower density of defect states is found at the grain boundaries in CuInSe(2), which is consistent with the experimental observation that CuInSe(2) solar cells exhibit high conversion efficiency without the need for deliberate passivation. Our investigations suggest that it is essential to effectively remove these defect states in order to improve the conversion efficiency of solar cells with Cu(2)ZnSnSe(4) as photovoltaic absorber materials. © 2011 American Chemical Society

  10. Doping dependent room-temperature ferromagnetism and structural properties of dilute magnetic semiconductor ZnO:Cu2+ nanorods

    International Nuclear Information System (INIS)

    Sharma, Prashant K.; Dutta, Ranu K.; Pandey, Avinash C.

    2009-01-01

    Copper doped ZnO nanoparticles were synthesized by the chemical technique based on the hydrothermal method. The crystallite structure, morphology and size were determined by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM) for different doping percentages of Cu 2+ (1-10%). TEM/SEM images showed formation of uniform nanorods, the aspect ratio of which varied with doping percentage of Cu 2+ . The wurtzite structure of ZnO gradually degrades with the increasing Cu 2+ doping concentration and an additional CuO associated diffraction peak was observed above 8% of Cu 2+ doping. The change in magnetic behavior of the nanoparticles of ZnO with varying Cu 2+ doping concentrations was investigated using a vibrating sample magnetometer (VSM). Initially these nanoparticles showed strong room-temperature ferromagnetic behavior, however at higher doping percentage of copper the ferromagnetic behavior was suppressed and paramagnetic nature was enhanced.

  11. Computer augumented modelling studies of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II complexes of L-glutamic acid in 1,2-propanediol–water mixtures

    Directory of Open Access Journals (Sweden)

    MAHESWARA RAO VEGI

    2008-12-01

    Full Text Available Chemical speciation of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II complexes of L-glutamic acid was studied at 303 K in 0–60 vol. % 1,2-propanediol–water mixtures, whereby the ionic strength was maintained at 0.16 mol dm-3. The active forms of the ligand are LH3+, LH2 and LH–. The predominant detected species were ML, ML2, MLH, ML2H and ML2H2. The trend of the variation in the stability constants with changing dielectric constant of the medium is explained based on the cation stabilizing nature of the co-solvents, specific solvent–water interactions, charge dispersion and specific interactions of the co-solvent with the solute. The effect of systematic errors in the concentrations of the substances on the stability constants is in the order alkali > > acid > ligand > metal. The bioavailability and transportation of metals are explained based on distribution diagrams and stability constants.

  12. Overexpression of Cu-Zn SOD in Brucella abortus suppresses bacterial intracellular replication via down-regulation of Sar1 activity

    Science.gov (United States)

    Liu, Xiaofeng; Zhou, Mi; Yang, Yanling; Wu, Jing; Peng, Qisheng

    2018-01-01

    Brucella Cu-Zn superoxide dismutase (Cu-Zn SOD) is a periplasmic protein, and immunization of mice with recombinant Cu-Zn SOD protein confers protection against Brucella abortus infection. However, the role of Cu-Zn SOD during the process of Brucella infection remains unknown. Here, we report that Cu-Zn SOD is secreted into culture medium and is translocated into host cells independent of type IV secretion systems (T4SS). Furthermore, co-immunoprecipitation and immunofluorescence studies reveal that Brucella abortus Cu-Zn SOD interacts with the small GTPase Sar1. Overexpression of Cu-Zn SOD in Brucella abortus inhibits bacterial intracellular growth by abolishing Sar1 activity in a manner independent of reactive oxygen species (ROS) production. PMID:29515756

  13. Synthesis, XRD, TEM, EPR, and Optical Absorption Spectral Studies of CuZnO2 Nanocompound

    Directory of Open Access Journals (Sweden)

    T. Ravindra Reddy

    2014-01-01

    Full Text Available Synthesis of nano CuZnO2 compound is carried out by thermal decomposition method. The crystalline phase of the material is characterized by XRD. The calculated unit cell constants are a=3.1 Å and c=3.4786 Å and are of tetragonal structure. The unit cell constants are different from wurtzite (hexagonal which indicate that a nanocompound is formed. Further TEM images reveal that the metal ion is in tetragonal structure with oxygen ligands. The prepared CuZnO2 is then characterized for crystallite size analysis by employing transmission electron microscopy (TEM. The size is found to be 100 nm. Uniform bright rings are noticed in the TEM picture suggesting that the nanocrystals have preferential instead of random orientations. The selected-area electron diffraction (SAED pattern clearly indicates the formation of CuO-ZnO nanocompound. The nature of bonding is studied by electron paramagnetic resonance (EPR. The covalency character is about 0.74 and thus the compound is electrically less conductive. Optical absorption spectral studies suggest that Cu(II is placed in tetragonal elongation crystal field. The spin-orbit coupling constant, λ, is calculated using the EPR and optical absorption spectral results suggest some covalent bond between metal and ligand. Near infrared (NIR spectra are due to hydroxyl and water fundamentals.

  14. Study of isobaric analogue states in 64Zn through proton capture by 63Cu

    International Nuclear Information System (INIS)

    Roy, A.; Iyengar, K.V.K.; Jhingan, M.L.

    1976-01-01

    The reaction 63 Cu(p,γ) 64 Zn has been studied in the proton energy range 1650-2750 keV using the Van de Graaff accelerator at B.A.R.C., Trombay. About 100 resonances were observed in the excitation function out of which the prominent ones at Esub(p)=1731, 1882, 2036, 2099, 2312, 2352, 2421 and 2479 keV have been identified as analogues of the ground and low-lying excited states of 64 Cu. The overall energy resolution was 2.5 keV. The Coulomb displacement energy for the isobaric pair 64 Cu- 64 Zn has been deduced to be 99.63 +- MeV. The spectra of γ-rays and their angular distributions have been obtained at resonances corresponding to the analogue of the ground and first four excited states of 64 Cu. The resonance strengths and the branching ratios for the γ-decay of the resonances has been presented. The M1 width of the γ-decay from resonance at 1751 keV to the ground state of 64 Zn, (0.20 +- 0.04)eV, is in excellent agreement with the value 0.19 eV deduced from the log ft value of 5.3 of the β decay of the parent analogue

  15. Assessment of the Bioavailability of Cu, Pb, and Zn through Petunia axillaris in Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Lydia Bondareva

    2014-01-01

    Full Text Available Heavy metals are potentially toxic to human life and the environment. Metal toxicity depends on chemical associations in soils. For this reason, determining the chemical form of a metal in soils is important to evaluate its mobility and the potential accumulation. The aim of this examination is to evaluate the accumulation potential of Petunia x hybrida as a flower crop for three metals, namely, copper (Cu, lead (Pb, and nickel (Ni. Trace metals (Zn, Cu, and Pb in the soils were partitioned by a sequential extraction procedure into H2O extractable (F1, 1 M CH3COONa extractable (F2. Chemical fractionation showed that F1 and F2 fraction of the metals were near 1% and residue was the dominant form for Zn, Cu, and Pb in all samples. Using fluorescence method allowed us to estimate condition of the plants by adding metals. As result of plant and soil analysis, we can conclude that Petunia has Cu, Zn, and Ni tolerance and accumulation. Therefore, Petunia has the potential to serve as a model species for developing herbaceous, ornamental plants for phytoremediation.

  16. Bioaccessibility of Ba, Cu, Pb, and Zn in urban garden and orchard soils

    International Nuclear Information System (INIS)

    Cai, Meifang; McBride, Murray B.; Li, Kaiming

    2016-01-01

    Exposure of young children to toxic metals in urban environments is largely due to soil and dust ingestion. Soil particle size distribution and concentrations of toxic metals in different particle sizes are important risk factors in addition to bioaccessibility of these metals in the particles. Analysis of particle size distribution and metals concentrations for 13 soils, 12 sampled from urban gardens and 1 from orchard found that fine particles (<105 μm) comprised from 22 to 66% by weight of the tested soils, with Ba, Cu, Pb and Zn generally at higher concentrations in the finer particles. However, metal bioaccessibility was generally lower in finer particles, a trend most pronounced for Ba and Pb. Gastric was higher than gastrointestinal bioaccessibility for all metals except Cu. The lower bioaccessibility of Pb in urban garden soils compared to orchard soil is attributable to the higher organic matter content of the garden soils. - Highlights: • The bioaccessibility of metals in urban garden and orchard soils was measured. • Ba, Cu, Pb, Zn were concentrated in fine particles of the soils. • Bioaccessibilities of Ba and Pb were generally lower in fine particles of soils. • Pb bioaccessibility was generally lower in soils with higher organic matter content. • Pb bioaccessibility was lower in urban garden soils than in an orchard soil. - Pb and other trace metals (Ba, Cu, Zn) were concentrated in fine particles of urban and orchard soils, but the bioaccessibility of Ba and Pb was generally lower in finer particles.

  17. A facile and low cost synthesis of earth abundant element Cu{sub 2}ZnSnS{sub 4} (CZTS) nanocrystals: Effect of Cu concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seung Wook; Han, Jun Hee [Department of Materials Science and Engineering, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Park, Chan Yeong; Kim, Sae-Rok; Park, Yeon Chan; Agawane, G.L. [Photonics Technology Research Institute, Department of Materials Science and Engineering, Chonnam National University, 300 Yongbong-Dong, Buk-Gu, Gwangju 500-757 (Korea, Republic of); Moholkar, A.V. [Electrochemical Mat. Lab, Department of Physics, Shivaji University, Kolhapur 416-004 (India); Yun, Jae Ho [Photovoltaic Research Group, Korea Institute of Energy Research, 71-2 Jang-Dong, Yuseong-Gu, Daejeon 305-343 (Korea, Republic of); Jeong, Chae Hwan [Solar City Center, Development of Advanced Components and Materials Korea Institute of Industrial Technology, Gwangju 500-480 (Korea, Republic of); Lee, Jeong Yong, E-mail: j.y.lee@kaist.ac.kr [Department of Materials Science and Engineering, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Jin Hyeok, E-mail: jinhyeok@chonnam.ac.kr [Photonics Technology Research Institute, Department of Materials Science and Engineering, Chonnam National University, 300 Yongbong-Dong, Buk-Gu, Gwangju 500-757 (Korea, Republic of)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Cu{sub 2}ZnSnS{sub 4} (CZTS) nanocrystals (NCs) were prepared by sulfurization of microwave assisted precursor without toxic chemicals. Black-Right-Pointing-Pointer Effect of Cu concentration on the properties of CZTS NCs was investigated using various analysis methods. Black-Right-Pointing-Pointer The properties of CZTS NCs was strongly related to the Cu concentrations. - Abstract: Cu{sub 2}ZnSnS{sub 4} (CZTS) nanocrystals (NCs) were synthesized by sulfurization of microwave assisted precursor powders without toxic chemicals. The effects of different Cu concentration from 0.01 to 0.025 M on the structural, morphological, compositional, chemical and optical properties of CZTS NCs were investigated. X-ray diffraction patterns, X-ray photoelectron spectroscopy and transmission electron microscopy results showed that the precursor powder contains several broad peaks that could not be assigned to CZTS, ZnS, Cu{sub 2-x}S, Sn{sub 2}S{sub 3} and Cu{sub 2}SnS{sub 3}. However, the sulfurized NCs showed both kesterite CZTS and Cu- and Sn-based secondary phases except for that formed at Cu concentration of 0.02 M. Inductively coupled plasma (ICP) results showed that the presence of Cu in the sulfurized CZTS NCs increased with increasing Cu concentration from 16.57 to 32.94 at.% while Zn and Sn in the sulfurized CZTS NCs decreased with increasing Cu concentration. UV-Vis spectroscopy results showed that the absorption coefficient of the sulfurized NCs was over 10{sup 4} cm{sup -1} in the visible region and band gap energy of the sulfurized CZTS NCs decreased from 1.65 to 1.28 eV with increasing Cu concentration.

  18. A density functional study on properties of a Cu{sub 3}Zn material and CO adsorption onto its surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Qian-Lin, E-mail: qltang@xidian.edu.cn [Department of Applied Chemistry, School of Advanced Materials and Nanotechnology, Xidian University, No. 2 South Taibai Road, Xi’an, Shaanxi 710071 (China); Duan, Xiao-Xuan; Liu, Bei; Wei, An-Qing; Liu, Sheng-Long [Department of Applied Chemistry, School of Advanced Materials and Nanotechnology, Xidian University, No. 2 South Taibai Road, Xi’an, Shaanxi 710071 (China); Wang, Qi, E-mail: qwang@mail.xidian.edu.cn [Department of Applied Chemistry, School of Advanced Materials and Nanotechnology, Xidian University, No. 2 South Taibai Road, Xi’an, Shaanxi 710071 (China); Liang, Yan-Ping, E-mail: ypliang@mail.xidian.edu.cn [Department of Applied Chemistry, School of Advanced Materials and Nanotechnology, Xidian University, No. 2 South Taibai Road, Xi’an, Shaanxi 710071 (China); Ma, Xiao-Hua [Department of Applied Chemistry, School of Advanced Materials and Nanotechnology, Xidian University, No. 2 South Taibai Road, Xi’an, Shaanxi 710071 (China); State Key Discipline Laboratory of Wide Bandgap Semiconductor Technology, School of Advanced Materials and Nanotechnology, Xidian University, No. 2 South Taibai Road, Xi’an, Shaanxi 710071 (China)

    2016-02-15

    Graphical abstract: Periodic first-principles calculations have been utilized to evaluate the bulk and surface properties of a Cu{sub 3}Zn alloy. - Highlights: • The bulk and surface properties of a DO{sub 23}-Cu{sub 3}Zn alloy were studied with DFT-GGA. • The stability of Cu{sub 3}Zn surfaces correlates with the coordination of surface atoms. • Both the (1 1 4) and (2 1 4) facets are most likely observed in Cu{sub 3}Zn alloy particles. • Covalent bonding influences overwhelmingly the adsorption between CO and Cu{sub 3}Zn. - Abstract: Prior experimental and theoretical efforts have provided strong evidence that the formation of α-brass such as Cu{sub 3}Zn alloys in Cu/ZnO/Al{sub 2}O{sub 3} CO{sub 2}/CO hydrogenation catalysts enhances dramatically the catalytic activity toward methanol synthesis. In this work, a density functional theory (DFT) slab model has been adopted to get information concerning the bulk and surface properties of DO{sub 23}-like Cu{sub 3}Zn and to explore CO molecular adsorption, which will help pave the way to future rationalization of the impact of surface alloying on Cu/ZnO-based catalysis for CO{sub 2} and CO hydrogenations. Our calculations imply that the bulk modulus and cohesive energy of the binary solid solution lie between the corresponding ones for the individual components, but only the former quantity equals its composition weighted average. From the DFT-computed surface energies, the stability of Cu{sub 3}Zn surfaces was predicted to be reinforced in the sequence (1 1 0) < (1 0 1) < (1 1 1) < (1 0 0) = (0 0 1) < (2 1 4) < (1 1 4), which can be interpreted as sensitive to the density change of surface dangling bonds. The downward shifts in the C–O stretch frequency measured experimentally over methanol synthesis catalysts at successively elevated reduction temperatures were correctly reproduced by the present simulation for the adsorption of CO to take place at Cu{sub 3}Zn(1 1 4), Cu{sub 3}Zn(2 1 4) and, as a reference

  19. PRECIPITATION BEHAVIOR IN A Cu-Sn-Ni-Zn-P LEAD FRAME MATERIAL

    Institute of Scientific and Technical Information of China (English)

    W.H. Tian; C.K. Yan; M.Nemoto

    2003-01-01

    Transmission electron microscopy (TEM) observations were carried out for examining the precipitation behavior in a Cu-Sn-Ni-Zn-P lead frame material. TEM observations revealed that the precipitate is hexagonal Ni5P2 and the orientation relationship between the Cu matrix and Ni5P2 precipitate is (111)fcc//(0001)hcp,[101]fcc//[11-20]hcp, where the suffix fcc denotes the Cu matrix and hcp denotes the hexagonal Ni5P2 precipitate. The NisP2 precipitate is ovoidal in shape at the beginning of aging at lower temperature. By prolonging the aging time or increasing the aging temperature, Ni5P2 precipitate grows and shows a rod-like shape. The Ni added Cu based lead frame material has a comparative mechanical properties with that of TAMAC15 which has been developed and used in electrical industry.

  20. Alterations of serum antioxidant trace elements (Se, Zn and Cu status in patients with cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Leila Farzin

    2014-02-01

    Full Text Available Objective: To assess the serum antioxidant trace elements selenium (Se, zinc (Zn and copper (Cu in cutaneous leishmaniasis patients. Methods: In this study, serum Se, Zn and Cu was determined by using atomic absorption spectrometry in patients with cutaneous leishmaniasis (n=95. The values were statistically compared between patients and control group (n=100 using One-way analysis of variance (ANOVA. Results: Our results showed that there was a significant difference in the values of Se and Zn between two groups (P0.05. Se and Zn levels were found to be (4.33依1.06 and (70.23依19.12 µg/dL in cutaneous leishmaniasis cases, and these values were found statistically lower compared to the controls (11.10依2.37 and (119.61依26.18 µg/dL, respectively. Conclusions: The observations that host products are released from stimulated leukocytes and could induce metabolic changes similar to an acute-phase response revealed an endocrine role for the immune system. Characteristic changes in trace-mineral metabolism are an integral part of the acute-phase response. The changes are usually reflected in decreased serum Se and Zn concentrations.

  1. Interface band gap narrowing behind open circuit voltage losses in Cu2ZnSnS4 solar cells

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Palsgaard, Mattias Lau Nøhr; Gunst, Tue

    2017-01-01

    We present evidence that bandgap narrowing at the heterointerface may be a major cause of the large open circuit voltage deficit of Cu2ZnSnS4/CdS solar cells. Bandgap narrowing is caused by surface states that extend the Cu2ZnSnS4valence band into the forbidden gap. Those surface states...... are consistently found in Cu2ZnSnS4, but not in Cu2ZnSnSe4, by first-principles calculations. They do not simply arise from defects at surfaces but are an intrinsic feature of Cu2ZnSnS4 surfaces. By including those states in a device model, the outcome of previously published temperature-dependent open circuit...... voltage measurements on Cu2ZnSnS4 solar cells can be reproduced quantitatively without necessarily assuming a cliff-like conduction band offset with the CdS buffer layer. Our first-principles calculations indicate that Zn-based alternative buffer layers are advantageous due to the ability of...

  2. Changes in serum selenium, copper, zinc levels and cu/zn ratio in patients with pulmonary tuberculosis during therapy.

    Science.gov (United States)

    Ciftci, T Ulukavak; Ciftci, B; Yis, O; Guney, Y; Bilgihan, A; Ogretensoy, M

    2003-10-01

    The effectiveness and success of antituberculosis therapy is mainly measured by its ability to identify the organism in the sputum. In certain cases, available tuberculosis tests are not satisfactory and do not provide enough information on the effectiveness of antituberculosis therapy. Copper (Cu), zinc (Zn), and selenium (Se) are the essential elements that play a crucial role in the immune system. The serum levels of these elements vary in many diseases including tuberculosis. In this study, we investigate whether the serum levels of Cu, Zn, and Se change during antituberculosis therapy. We have included 22 pulmonary tuberculosis cases that were newly diagnosed with positive sputum and 18 healthy subjects. At the beginning and 2 mo after therapy, serum levels of Cu, Zn, and Se were measured by atomic absorption spectrometry. Despite Se and Cu levels not being affected during the treatment, we found that there was a significant increase in the levels of Zn and a decrease in the Cu/Zn ratio. Serum Zn levels and the Cu/Zn ratio could be used as a valuable laboratory tool for the clinicians to assess response to therapy or effectiveness of the ongoing antituberculosis therapy.

  3. Electrodeposited semiconductors at room temperature: an X-ray Absorption Spectroscopy study of Cu-, Zn-, S-bearing thin films

    International Nuclear Information System (INIS)

    Di Benedetto, Francesco; Cinotti, Serena; D’Acapito, Francesco; Vizza, Francesco; Foresti, Maria Luisa; Guerri, Annalisa; Lavacchi, Alessandro; Montegrossi, Giordano; Romanelli, Maurizio; Cioffi, Nicola; Innocenti, Massimo

    2015-01-01

    A SEM, DRS and XAS study was carried out on ultra-thin films with chemical composition belonging to the Cu-Zn-S ternary system, related to the kesterite-type materials, in the light of their potential application to thin film photovoltaic technology. The films, realized through the layer-by-layer E-ALD electrochemical technique, reveal variable phase composition as a function of the applied E-ALD sequence. In particular, by increasing the Zn cycles per Cu cycle from 1:1 to 9:1, the number of detected phases changes from 3 to 2. In all samples, Cu mainly crystallize in a Cu_2S type phase, whereas Zn occurs as ZnS. In the 1:1 sample, additional ZnO is detected. The variable phase composition parallels apparent changes in the sample morphology. In all samples, a sulphide thin film is covered by a net of elongated nanostructures, the length of which decreases with increasing the number of Zn cycles per Cu cycle. All these evidences are interpreted as due to the operating electrochemical route during the synthesis and confirm the lack of miscibility between Cu_2S and ZnS, thermodynamically relevant after the E-ALD has stopped. The band gap values exhibited by the three films, modulated by changing the copper:zinc ratio, progressively approach a value useful for solar energy conversion, thus strongly proposing these new sulfide nanomaterials for photovoltaics and photochemical applications.

  4. Averaged cross sections for the reactions 68Zn(n,p)68gCu and 68Zn(n,p)68mCu for a 235U fission neutron spectrum

    International Nuclear Information System (INIS)

    Kestelman, A.J.; Ribeiro Guevara, S.; Arribere, M.A.; Cohen, I.M.

    2007-01-01

    Making use of the method developed in our laboratory for the simultaneous determination of cross sections leading to both the ground and metastable states, we have measured the 68 Zn(n,p) 68g Cu and 68 Zn(n,p) 68m Cu reactions, using Zn enriched to 99.4% in its isotope 68 Zn. The measured cross sections are (15.04±0.35) and (3.69±0.30) μb for the ground and metastable state, respectively. However, a direct determination of the cross section leading to the metastable state gives a value of (4.75±0.38) μb. A possible reason for this discrepancy-which is outside experimental uncertainties-is that some tabulated values used in our calculations for the decay parameters of 68g Cu and 68m Cu, have either larger than quoted, or unknown systematic, uncertainties

  5. Averaged cross sections for the reactions {sup 68}Zn(n,p){sup 68g}Cu and {sup 68}Zn(n,p){sup 68m}Cu for a {sup 235}U fission neutron spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Kestelman, A.J. [Laboratorio de Analisis por Activacion Neutronica, Centro Atomico Bariloche e Instituto Balseiro, Comision Nacional de Energia Atomica y Universidad Nacional de Cuyo, 8400 Bariloche (Argentina)]. E-mail: kestelma@cab.cnea.gov.ar; Ribeiro Guevara, S. [Laboratorio de Analisis por Activacion Neutronica, Centro Atomico Bariloche e Instituto Balseiro, Comision Nacional de Energia Atomica y Universidad Nacional de Cuyo, 8400 Bariloche (Argentina); Arribere, M.A. [Laboratorio de Analisis por Activacion Neutronica, Centro Atomico Bariloche e Instituto Balseiro, Comision Nacional de Energia Atomica y Universidad Nacional de Cuyo, 8400 Bariloche (Argentina); Cohen, I.M. [Universidad Tecnologica Nacional, Facultad Regional Buenos Aires, Medrano 951 (C1179AAQ) Buenos Aires (Argentina)

    2007-07-15

    Making use of the method developed in our laboratory for the simultaneous determination of cross sections leading to both the ground and metastable states, we have measured the {sup 68}Zn(n,p){sup 68g}Cu and {sup 68}Zn(n,p){sup 68m}Cu reactions, using Zn enriched to 99.4% in its isotope {sup 68}Zn. The measured cross sections are (15.04{+-}0.35) and (3.69{+-}0.30) {mu}b for the ground and metastable state, respectively. However, a direct determination of the cross section leading to the metastable state gives a value of (4.75{+-}0.38) {mu}b. A possible reason for this discrepancy-which is outside experimental uncertainties-is that some tabulated values used in our calculations for the decay parameters of {sup 68g}Cu and {sup 68m}Cu, have either larger than quoted, or unknown systematic, uncertainties.

  6. SYNTHESIS, CHARACTERIZATION AND BIOACTIVITY Zn2+, Cu2+ ...

    African Journals Online (AJOL)

    transition metal complexes possess obvious biologically and pharmaceutically liveliness in medical ...... 2+ complex (13) displays one peak at 500 nm referred to ligand to uranium charge transfer [50]. ..... the oxidation of olefins. Inorg. Chim.

  7. Fibroblast responses and antibacterial activity of Cu and Zn co-doped TiO2 for percutaneous implants

    Science.gov (United States)

    Zhang, Lan; Guo, Jiaqi; Yan, Ting; Han, Yong

    2018-03-01

    In order to enhance skin integration and antibacterial activity of Ti percutaneous implants, microporous TiO2 coatings co-doped with different doses of Cu2+ and Zn2+ were directly fabricated on Ti via micro-arc oxidation (MAO). The structures of coatings were investigated; the behaviors of fibroblasts (L-929) as well as the response of Staphylococcus aureus (S. aureus) were evaluated. During the MAO process, a large number of micro-arc discharges forming on Ti performed as penetrating channels; O2-, Ca2+, Zn2+, Cu2+ and PO43- delivered via the channels, giving rise to the formation of doped TiO2. Surface characteristics including phase component, topography, surface roughness and wettability were almost the same for different coatings, whereas, the amount of Cu doped in TiO2 decreased with the increased Zn amount. Compared with Cu single-doped TiO2 (0.77 Wt% Cu), the co-doped with appropriate amounts of Cu and Zn, for example, 0.55 Wt% Cu and 2.53 Wt% Zn, further improved proliferation of L-929, facilitated fibroblasts to switch to fibrotic phenotype, and enhanced synthesis of collagen I as well as the extracellular collagen secretion; the antibacterial properties including contact-killing and release-killing were also enhanced. By analyzing the relationship of Cu/Zn amount in TiO2 and the behaviors of L-929 and S. aureus, it can be deduced that when the doped Zn is in a low dose (<1.79 Wt%), the behaviors of L-929 and S. aureus are sensitive to the reduced amount of Cu2+, whereas, Zn2+ plays a key role in accelerating fibroblast functions and reducing S. aureus when its dose obviously increases from 2.63 to 6.47 Wt%.

  8. Cu2ZnSnS4 thin film solar cells from electroplated precursors: Novel low-cost perspective

    International Nuclear Information System (INIS)

    Ennaoui, A.; Lux-Steiner, M.; Weber, A.; Abou-Ras, D.; Koetschau, I.; Schock, H.-W.; Schurr, R.; Hoelzing, A.; Jost, S.; Hock, R.; Voss, T.; Schulze, J.; Kirbs, A.

    2009-01-01

    Thin-film solar cells based on Cu 2 ZnSnS 4 (CZTS) absorbers were fabricated successfully by solid-state reaction in H 2 S atmosphere of electrodeposited Cu-Zn-Sn precursors. These ternary alloys were deposited in one step from a cyanide-free alkaline electrolyte containing Cu(II), Zn (II) and Sn (IV) metal salts on Mo-coated glass substrates. The solar cell was completed by a chemical bath-deposited CdS buffer layer and a sputtered i-ZnO/ZnO:Al bilayer. The best solar cell performance was obtained with Cu-poor samples. A total area (0.5 cm 2 ) efficiency of 3.4% is achieved (V oc = 563 mV, j sc = 14.8 mA/cm 2 , FF = 41%) with a maximum external quantum efficiency (EQE) of 80%. The estimated band-gap energy from the external quantum efficiency (EQE) measurements is about 1.54 eV. Electron backscatter-diffraction maps of cross-section samples revealed CZTS grain sizes of up to 10 μm. Elemental distribution maps of the CZTS absorber show Zn-rich precipitates, probably ZnS, and a Zn-poor region, presumably Cu 2 SnS 3 , close to the interface Mo/CZTS

  9. Vibrational properties of stannite and kesterite type compounds: Raman scattering analysis of Cu2(Fe,Zn)SnS4

    International Nuclear Information System (INIS)

    Fontané, X.; Izquierdo-Roca, V.; Saucedo, E.; Schorr, S.; Yukhymchuk, V.O.; Valakh, M.Ya.; Pérez-Rodríguez, A.; Morante, J.R.

    2012-01-01

    Highlights: ► Analysis of main and weaker Raman peaks from Cu 2 FeZnS 4 and Cu 2 ZnSnS 4 compounds. ► Identification of a cation disorder induced Raman peak in Cu 2 ZnSnS 4 . ► Analysis of spectral features of main Raman peaks from Cu 2 (Fe,Zn)SnS 4 . - Abstract: This work reports the analysis of the vibrational properties of stannite–kesterite Cu 2 (Fe,Zn)SnS 4 compounds that has been performed by Raman scattering measurements. The detailed analysis of the experimental spectra has allowed determining the frequency and symmetry assignment of the main and weaker peaks from both stannite Cu 2 FeSnS 4 (CFTS) and kesterite Cu 2 ZnSnS 4 (CZTS) phases. The measurements performed in the kesterite CZTS samples have also revealed the presence of local inhomogeneities that are characterised by an additional peak in the spectra at about 331 cm −1 . This peak has been related to the presence in these local regions of a high degree of disorder in the cation sublattice, in agreement with previous neutron diffraction analysis in similar samples. Finally, the spectra from the solid solution alloys show a one-mode behaviour of the main A/A 1 peak with the chemical composition.

  10. Biocompatibility Assessment of Novel Bioresorbable Alloys Mg-Zn-Se and Mg-Zn-Cu for Endovascular Applications: In- Vitro Studies.

    Science.gov (United States)

    Persaud-Sharma, Dharam; Budiansky, Noah; McGoron, Anthony J

    2013-01-01

    Previous studies have shown that using biodegradable magnesium alloys such as Mg-Zn and Mg-Zn-Al possess the appropriate mechanical properties and biocompatibility to serve in a multitude of biological applications ranging from endovascular to orthopedic and fixation devices. The objective of this study was to evaluate the biocompatibility of novel as-cast magnesium alloys Mg-1Zn-1Cu wt.% and Mg-1Zn-1Se wt.% as potential implantable biomedical materials, and compare their biologically effective properties to a binary Mg-Zn alloy. The cytotoxicity of these experimental alloys was evaluated using a tetrazolium based- MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay and a lactate dehydrogenase membrane integrity assay (LDH). The MTS assay was performed on extract solutions obtained from a 30-day period of alloy immersion and agitation in simulated body fluid to evaluate the major degradation products eluted from the alloy materials. Human foreskin fibroblast cell growth on the experimental magnesium alloys was evaluated for a 72 hour period, and cell death was quantified by measuring lactate dehydrogenase concentrations. Both Mg-Zn-Se and Mg-Zn-Cu alloys exhibit low cytotoxicity levels which are suitable for biomaterial applications. The Mg-Zn-Cu alloy was found to completely degrade within 72 hours, resulting in lower human foreskin fibroblast cell viability. The Mg-Zn-Se alloy was shown to be less cytotoxic than both the Mg-Zn-Cu and Mg-Zn alloys.

  11. Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn

    International Nuclear Information System (INIS)

    Biesinger, Mark C.; Lau, Leo W.M.; Gerson, Andrea R.; Smart, Roger St.C.

    2010-01-01

    Chemical state X-ray photoelectron spectroscopic analysis of first row transition metals and their oxides and hydroxides is challenging due to the complexity of the 2p spectra resulting from peak asymmetries, complex multiplet splitting, shake-up and plasmon loss structure, and uncertain, overlapping binding energies. A review of current literature shows that all values necessary for reproducible, quantitative chemical state analysis are usually not provided. This paper reports a more consistent, practical and effective approach to curve-fitting the various chemical states in a variety of Sc, Ti, V, Cu and Zn metals, oxides and hydroxides. The curve-fitting procedures proposed are based on a combination of (1) standard spectra from quality reference samples, (2) a survey of appropriate literature databases and/or a compilation of the literature references, and (3) specific literature references where fitting procedures are available. Binding energies, full-width at half maximum (FWHM) values, spin-orbit splitting values, asymmetric peak-shape fitting parameters, and, for Cu and Zn, Auger parameters values are presented. The quantification procedure for Cu species details the use of the shake-up satellites for Cu(II)-containing compounds and the exact binding energies of the Cu(0) and Cu(I) peaks. The use of the modified Auger parameter for Cu and Zn species allows for corroborating evidence when there is uncertainty in the binding energy assignment. These procedures can remove uncertainties in analysis of surface states in nano-particles, corrosion, catalysis and surface-engineered materials.

  12. Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn

    Energy Technology Data Exchange (ETDEWEB)

    Biesinger, Mark C., E-mail: biesingr@uwo.ca [Surface Science Western, University of Western Ontario, University of Western Ontario Research Park, Room LL31, 999 Collip Circle, London, Ontario, N6G 0J3 (Canada); ACeSSS (Applied Centre for Structural and Synchrotron Studies), University of South Australia, Mawson Lakes, SA 5095 (Australia); Lau, Leo W.M. [Surface Science Western, University of Western Ontario, University of Western Ontario Research Park, Room LL31, 999 Collip Circle, London, Ontario, N6G 0J3 (Canada); Department of Chemistry, University of Western Ontario, London, Ontario, N6A 5B7 (Canada); Gerson, Andrea R.; Smart, Roger St.C. [ACeSSS (Applied Centre for Structural and Synchrotron Studies), University of South Australia, Mawson Lakes, SA 5095 (Australia)

    2010-11-15

    Chemical state X-ray photoelectron spectroscopic analysis of first row transition metals and their oxides and hydroxides is challenging due to the complexity of the 2p spectra resulting from peak asymmetries, complex multiplet splitting, shake-up and plasmon loss structure, and uncertain, overlapping binding energies. A review of current literature shows that all values necessary for reproducible, quantitative chemical state analysis are usually not provided. This paper reports a more consistent, practical and effective approach to curve-fitting the various chemical states in a variety of Sc, Ti, V, Cu and Zn metals, oxides and hydroxides. The curve-fitting procedures proposed are based on a combination of (1) standard spectra from quality reference samples, (2) a survey of appropriate literature databases and/or a compilation of the literature references, and (3) specific literature references where fitting procedures are available. Binding energies, full-width at half maximum (FWHM) values, spin-orbit splitting values, asymmetric peak-shape fitting parameters, and, for Cu and Zn, Auger parameters values are presented. The quantification procedure for Cu species details the use of the shake-up satellites for Cu(II)-containing compounds and the exact binding energies of the Cu(0) and Cu(I) peaks. The use of the modified Auger parameter for Cu and Zn species allows for corroborating evidence when there is uncertainty in the binding energy assignment. These procedures can remove uncertainties in analysis of surface states in nano-particles, corrosion, catalysis and surface-engineered materials.

  13. Synthesis of ZnO Nanowires via Hotwire Thermal Evaporation of Brass (CuZn Assisted by Vapor Phase Transport of Methanol

    Directory of Open Access Journals (Sweden)

    Tamil Many K. Thandavan

    2014-01-01

    Full Text Available Zinc oxide (ZnO nanowires (NWs were synthesized using vapor phase transport (VPT and thermal evaporation of Zn from CuZn. Time dependence of ZnO NWs growth was investigated for 5, 10, 15, 20, 25, and 30 minutes. Significant changes were observed from the field electron scanning electron microscopy (FESEM images as well as from the X-ray diffraction (XRD profile. The photoluminescence (PL profile was attributed to the contribution of oxygen vacancy, zinc interstitials, and hydrogen defects in the ZnO NWs. Raman scattering results show a significant peak at 143 cm−1 and possible functionalization on the wall of ZnO NWs. Growth of ZnO NWs in (0002 with an estimated distance between adjacent lattice planes 0.26 nm was determined from transmission electron microscopy (TEM analysis.

  14. Transient and modulated charge separation at CuInSe{sub 2}/C{sub 60} and CuInSe{sub 2}/ZnPc hybrid interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Morzé, Natascha von, E-mail: natascha.von_morze@helmholtz-berlin.de; Dittrich, Thomas, E-mail: dittrich@helmholtz-berlin.de; Calvet, Wolfram, E-mail: wolfram.calvet@helmholtz-berlin.de; Lauermann, Iver, E-mail: iver.lauermann@helmholtz-berlin.de; Rusu, Marin, E-mail: rusu@helmholtz-berlin.de

    2017-02-28

    Highlights: • Surface physical properties of non- and Na-treated CuInSe{sub 2} layers studied. • Evidence of exciton dissociation and charge separation at CuInSe{sub 2}/ZnPc interface. • Strong band bending at the CuInSe{sub 2} surface in contact with C{sub 60} observed. • No evidence for exciton dissociation at the CuInSe{sub 2}/C{sub 60} interface found. • Cu-poor phase at CuInSe{sub 2}/organic interface crucial for charge separation. - Abstract: Spectral dependent charge transfer and exciton dissociation have been investigated at hybrid interfaces between inorganic polycrystalline CuInSe{sub 2} (untreated and Na-conditioned) thin films and organic C{sub 60} as well as zinc phthalocyanine (ZnPc) layers by transient and modulated surface photovoltage measurements. The stoichiometry and electronic properties of the bare CuInSe{sub 2} surface were characterized by photoelectron spectroscopy which revealed a Cu-poor phase with n-type features. After the deposition of the C{sub 60} layer, a strong band bending at the CuInSe{sub 2} surface was observed. Evidence for dissociation of excitons followed by charge separation was found at the CuInSe{sub 2}/ZnPc interface. The Cu-poor layer at the CuInSe{sub 2} surface was found to be crucial for transient and modulated charge separation at CuInSe{sub 2}/organic hybrid interfaces.

  15. Intermixing at the heterointerface between ZnS /Zn(S,O) bilayer buffer and CuInS2 thin film solar cell absorber

    Science.gov (United States)

    Bär, M.; Ennaoui, A.; Klaer, J.; Kropp, T.; Sáez-Araoz, R.; Lehmann, S.; Grimm, A.; Lauermann, I.; Loreck, Ch.; Sokoll, St.; Schock, H.-W.; Fischer, Ch.-H.; Lux-Steiner, M. C.; Jung, Ch.

    2006-09-01

    The application of Zn compounds as buffer layers was recently extended to wide-gap CuInS2 (CIS) based thin-film solar cells. Using an alternative chemical deposition route for the buffer preparation aiming at the deposition of a single-layer, nominal ZnS buffer without the need for any toxic reactants such as hydrazine has helped us to achieve a similar efficiency as respective CdS-buffered reference devices. After identifying the deposited Zn compound, as ZnS /Zn(S,O) bilayer buffer in former investigations [M. Bär et al., J. Appl. Phys. 99, 123503 (2006)], this time the focus lies on potential diffusion/intermixing processes at the buffer/absorber interface possibly, clarifying the effect of the heat treatment, which drastically enhances the device performance of respective final solar cells. The interface formation was investigated by x-ray photoelectron and x-ray excited Auger electron spectroscopy. In addition, photoelectron spectroscopy (PES) measurements were also conducted using tunable monochromatized synchrotron radiation in order to gain depth-resolved information. The buffer side of the buffer/absorber heterointerface was investigated by means of the characterization of Zn(S ,O)/ZnS/CIS structures where the ZnS /Zn(S,O) bilayer buffer was deposited successively by different deposition times. In order to make the (in terms of PES information depth) deeply buried absorber side of the buffer/absorber heterointerface accessible for characterization, in these cases the buffer layer was etched away by dilute HClaq. We found indications that while (out-leached) Cu from the absorber layer forms together with the educts in the chemical bath a [Zn(1-Z ),Cu2Z]S-like interlayer between buffer and absorber, Zn is incorporated in the uppermost region of the absorber. Both effects are strongly enhanced by postannealing the Zn(S ,O)/ZnS/CIS samples. However, it was determined that the major fraction of the Cu and Zn can be found quite close to the heterointerface in

  16. Mechanisms for activating Cu- and Zn-containing superoxide dismutase in the absence of the CCS Cu chaperone.

    Science.gov (United States)

    Carroll, Mark C; Girouard, Jody B; Ulloa, Janella L; Subramaniam, Jamuna R; Wong, Phillip C; Valentine, Joan Selverstone; Culotta, Valeria Cizewski

    2004-04-20

    The Cu- and Zn-containing superoxide dismutase 1 (SOD1) largely obtains Cu in vivo by means of the action of the Cu chaperone CCS. Yet, in the case of mammalian SOD1, a secondary pathway of activation is apparent. Specifically, when human SOD1 is expressed in either yeast or mammalian cells that are null for CCS, the SOD1 enzyme retains a certain degree of activity. This CCS-independent activity is evident with both wild-type and mutant variants of SOD1 that have been associated with familial amyotrophic lateral sclerosis. We demonstrate here that the CCS-independent activation of mammalian SOD1 involves glutathione, particularly the reduced form, or GSH. A role for glutathione in CCS-independent activation was seen with human SOD1 molecules that were expressed in either yeast cells or immortalized fibroblasts. Compared with mammalian SOD1, the Saccharomyces cerevisiae enzyme cannot obtain Cu without CCS in vivo, and this total dependence on CCS involves the presence of dual prolines near the C terminus of the SOD1 polypeptide. Indeed, the insertion of such prolines into human SOD1 rendered this molecule refractory to CCS-independent activation. The possible implications of multiple pathways for SOD1 activation are discussed in the context of SOD1 evolutionary biology and familial amyotrophic lateral sclerosis.

  17. Determination of Fe, Cu and Zn in sugar-cane spirits commercialized in Southeastern Brazil by TXRF

    International Nuclear Information System (INIS)

    Cunha e Silva, R.M.; Almeida, E.; Valencia, E.P.E.; Nascimento Filho, V.F.

    2004-01-01

    Total reflection X-ray fluorescence (TXRF) was used to determine simultaneously the concentration of Cu, Fe and Zn in seven sugar-cane spirit samples ('aguardente'), a processed alcoholic beverage made from the fermentation and distillation of sugar-cane juice. The limits of detection ranged from 35 to 8 ng x ml -1 for V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As and Se. Excluding Fe, Cu and Zn, the concentrations were below their limits. Two samples showed Cu concentrations higher than the value allowed by Brazilian legislation (5 μg x ml -1 ), and concerning Fe and Zn, no sample were above the limits permitted by WHO for drinking water (2 and 3 μg x ml -1 , respectively). (author)

  18. Speciation of ZnO and CuO nanoparticles exposed to culture medium and lymphocyte cells

    Data.gov (United States)

    U.S. Environmental Protection Agency — Spectral fits and linear combination data for ZnO and CuO nanoparticles exposure during toxicity testing. This dataset is associated with the following publication:...

  19. Effect of Cu concentration on the formation of Cu{sub 1−x} Zn{sub x} shape memory alloy thin films

    Energy Technology Data Exchange (ETDEWEB)

    Karahan, İsmail Hakkı [Department of Physics, Mustafa Kemal University, Hatay 31000 (Turkey); Özdemir, Rasim, E-mail: ihkarahan@gmail.com [Department of Physics, Mustafa Kemal University, Hatay 31000 (Turkey); Kilis Vocational High School, Kilis 7 Aralık University, 79000 Kilis (Turkey)

    2014-11-01

    Highlights: • 3 different composition of Cu–Zn deposits successfully deposited from the non-cyanide sulphate electrolyte. • The homogeneous metal films and Cu–Zn alloys were electrodeposited on Al substrate. • The effect of Cu content was strongly effected structural and the electrical resistivity of Cu–Zn alloys. • The average crystallite size of the samples varied from 66 to 100 nm and decreased when Cu content in the electrolyte. • Microstrain has been decreased with increasing crystallite size. • Cyclic voltammetry of the electrolyte explained the characters of the baths. - Abstract: The Cu{sub x}Zn1−x (x = 0.06, 0.08, 0.1) deposits were fabricated by a electrodeposition method. The structural and electrical properties of the films were investigated by cyclic voltammetry (CV), X-ray diffraction (XRD), Scanning electron micrograph (SEM), and DC resistivity measurements. Phase identification of the samples was studied by the XRD patterns. XRD patterns shows the characteristics XRD peaks corresponding to the, β, and γ phases. The grain sizes of the samples were decreased whereas microstrain increased with the increase in Cu{sup 2+} substitution. The SEM study reveals the fine particle nature of the samples with increasing Cu content. DC resistivity indicates the metallic nature of the prepared samples. It has been found that the Cu ions have a critical influence on the resultant structure and resistivity properties of the Cu–Zn samples.

  20. Evaluation of structural, morphological and magnetic properties of CuZnNi (Cu_xZn_0_._5_−_xNi_0_._5Fe_2O_4) nanocrystalline ferrites for core, switching and MLCI’s applications

    International Nuclear Information System (INIS)

    Akhtar, Majid Niaz; Khan, Muhammad Azhar; Ahmad, Mukhtar; Nazir, M.S.; Imran, M.; Ali, A.; Sattar, A.; Murtaza, G.

    2017-01-01

    The influence of Cu substitution on the structural and morphological characteristics of Ni–Zn nanocrystalline ferrites have been discussed in this work. The detailed and systematic magnetic characterizations were also done for Cu substituted Ni–Zn nanoferrites. The nanocrystalline ferrites of Cu substituted Cu_xZn_0_._5_−_xNi_0_._5Fe_2O_4 ferrites (x=0, 0.1, 0.2, 0.3, 0.4 and 0.5) were synthesized using sol gel self-combustion hybrid method. X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Transmission electron microscope (TEM) and Vibrating sample magnetometer (VSM) were used to investigate the properties of Cu substituted nanocrystalline ferrites. Single phase structure of Cu substituted in Ni–Zn nanocrystalline ferrites were investigated for all the samples. Crystallite size, lattice constant and volume of the cell were found to increase by increasing Cu contents in spinel structure. The better morphology with well-organized nanocrystals of Cu–Zn–Ni ferrites at x=0 and 0.5 were observed from both FESEM and TEM analysis. The average grain size was 35–46 nm for all prepared nanocrystalline samples. Magnetic properties such as coercivity, saturation, remanence, magnetic squareness, magneto crystalline anisotropy constant (K) and Bohr magneton were measured from the recorded M–H loops. The magnetic saturation and remanence were increased by the incorporation of Cu contents. However, coercivity follow the Stoner-Wolforth model except for x=0.3 which may be due to the site occupancy and replacement of Cu contents from octahedral site. The squareness ratio confirmed the super paramgnetic behaviour of the Cu substituted in Ni–Zn nanocrystalline ferrites. Furthermore, Cu substituted Ni–Zn nanocrystalline ferrites may be suitable for many industrial and domestic applications such as components of transformers, core, switching, and MLCI’s due to variety of the soft magnetic characteristics. - Highlights: • Cu substituted

  1. Role of microbial inoculation and chitosan in phytoextraction of Cu, Zn, Pb and Cd by Elsholtzia splendens - a field case

    Energy Technology Data Exchange (ETDEWEB)

    Wang Fayuan [Agricultural College, Henan University of Science and Technology, 70 Tianjin Road, Luoyang, Henan Province 471003 (China) and Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008 (China)]. E-mail: wfy1975@163.com; Lin Xiangui [Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008 (China); Yin Rui [Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu Province 210008 (China)

    2007-05-15

    A field experiment was carried out to study the effect of microbial inoculation on heavy metal phytoextraction by Elsholtzia splendens and whether chitosan could have a synergistic effect with the microbial inocula. The microbial inocula consisted of a consortium of arbuscular mycorrhizal fungi and two Penicillium fungi. Three treatments were included: the control, inoculation with microbial inocula, and the inoculation combined with chitosan. Microbial inoculation increased plant biomass especially shoot dry weight, enhanced shoot Cu, Zn and Pb concentrations but did not affect Cd, leading to higher shoot Cu, Zn, Pb and Cd uptake. Compared with microbial inoculation alone, chitosan application did not affect plant growth but increased shoot Zn, Pb and Cd concentrations except Cu, which led to higher phytoextraction efficiencies and partitioning to shoots of Zn, Pb and Cd. These results indicated synergistic effects between microbial inocula and chitosan on Zn, Pb and Cd phytoextraction. - Co-application of microbial inocula and chitosan enhanced heavy metal phytoextraction by E. splendens.

  2. Role of microbial inoculation and chitosan in phytoextraction of Cu, Zn, Pb and Cd by Elsholtzia splendens - a field case

    International Nuclear Information System (INIS)

    Wang Fayuan; Lin Xiangui; Yin Rui

    2007-01-01

    A field experiment was carried out to study the effect of microbial inoculation on heavy metal phytoextraction by Elsholtzia splendens and whether chitosan could have a synergistic effect with the microbial inocula. The microbial inocula consisted of a consortium of arbuscular mycorrhizal fungi and two Penicillium fungi. Three treatments were included: the control, inoculation with microbial inocula, and the inoculation combined with chitosan. Microbial inoculation increased plant biomass especially shoot dry weight, enhanced shoot Cu, Zn and Pb concentrations but did not affect Cd, leading to higher shoot Cu, Zn, Pb and Cd uptake. Compared with microbial inoculation alone, chitosan application did not affect plant growth but increased shoot Zn, Pb and Cd concentrations except Cu, which led to higher phytoextraction efficiencies and partitioning to shoots of Zn, Pb and Cd. These results indicated synergistic effects between microbial inocula and chitosan on Zn, Pb and Cd phytoextraction. - Co-application of microbial inocula and chitosan enhanced heavy metal phytoextraction by E. splendens

  3. Mechanical properties of Bi-In-Zn/ Cu solder joint system

    International Nuclear Information System (INIS)

    Ervina Efzan Mohd Noor; Mohammed Noori Ridha; Ahmad Badri Ismail; Nurulakmal Mohd Sharif; Kuan Yew Cheong; Tadashi Ariga; Zuhailawati Hussain

    2009-01-01

    Full text: In recent years, the pollution of environment from lead (Pb) and Pb-containing compounds in microelectronic devices attracts more and more attentions in academia and industry; the lead-free solder alloys begin to replace the lead-based solders in packaging process of some devices and components. In this works, microstructure and mechanical properties of different reflow temperature (80, 100, 120 and 140 degree Celsius) for solder joints on shear strength of Bi-In-Zn lead free solder with low melting temperature of 60 degree Celsius on Cu solder joint has been investigated. This paper will compared the mechanical properties of the Bi-In-Zn lead-free solder alloys with current lead-free solder, Sn-Ag-Cu solder alloy. The fracture surface analyses have been observed by Optical Microscope and were investigated by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDX) and proved it by X-ray diffraction (XRD). (author)

  4. Influence of heat treatment on corrosion behaviour of Al-Zn-Mg-Cu-Zr-Sc alloy

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Y.P.; Liu, X.Y.; He, Y.B. [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Pan, Q.L. [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education, Changsha 410083 (China); Li, W.B. [School of Materials Science and Engineering, Central South University, Changsha 410083 (China); School of Civil Engineering, Hunan City University, Yiyang 413000 (China)

    2012-05-15

    Corrosion behaviour of different tempers (namely NA, UA, PA and OA) of Al-Zn-Mg-Cu-Zr-Sc alloy was studied by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), optical microscopy (OM) and transmission electron microscopy (TEM). Over aged (OA) can decrease the susceptibility to exfoliation due to the discontinuous distribution of the {eta} precipitates at the grain boundaries, cause a negative shift of the corrosion potential (E{sub corr}), and lead to the prolonging of the time of the appearance of two time constants in impedance diagrams. In addition, Al-Zn-Mg-Cu-Zr-Sc alloy with over aged treatment has an enhanced resistance to exfoliation corrosion. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Heavy metal (Cu, Cr, Zn, and Fe) concentration on coralreef in panjang island coastal, Jepara

    International Nuclear Information System (INIS)

    Heni Susiati; Yarianto SBS; Ali Arman L; Yulizon Menri

    2008-01-01

    Observation on the accumulation of Cu, Cr, Zn, and Fe heavy metals in coral tissue were carried out in Panjang island, Jepara by NAA method. The purpose of this research is to determine the concentration of heavy metals on coral reef tissue in order to update environmental data to support site licensing and Environmental Impact Assessment (EIA) of Nuclear Power Plants (NPP). The result indicated that the concentration of Zn is 1,78 - 42,34 ppm, Cu is undetected - 0,41 ppm, Cr is 0,03 - 0,35 ppm and Fe is 5,25 - 30,56 ppm. The data shows that the accumulation of heavy metals in the coral reef tissue is higher than environmental threshold value, especially for marine biota life referring to the Environmental Ministry Decree Number 51 year 2004. (author)

  6. Spectroscopic ellipsometry study of Cu2ZnSnS4 bulk poly-crystals

    Science.gov (United States)

    Levcenko, S.; Hajdeu-Chicarosh, E.; Garcia-Llamas, E.; Caballero, R.; Serna, R.; Bodnar, I. V.; Victorov, I. A.; Guc, M.; Merino, J. M.; Pérez-Rodriguez, A.; Arushanov, E.; León, M.

    2018-04-01

    The linear optical properties of Cu2ZnSnS4 bulk poly-crystals have been investigated using spectroscopic ellipsometry in the range of 1.2-4.6 eV at room temperature. The characteristic features identified in the optical spectra are explained by using the Adachi analytical model for the interband transitions at the corresponding critical points in the Brillouin zone. The experimental data have been modeled over the entire spectral range taking into account the lowest E0 transition near the fundamental absorption edge and E1A and E1B higher energy interband transitions. In addition, the spectral dependences of the refractive index, extinction coefficient, absorption coefficient, and normal-incidence reflectivity values have been accurately determined and are provided since they are essential data for the design of Cu2ZnSnS4 based optoelectronic devices.

  7. Atmospheric Deposition of Pb, Zn, Cu, and Cd in Amman, Jordan

    International Nuclear Information System (INIS)

    Momani, K.A.; Jiries, A.G.; Jaradat, Q.M.

    1999-01-01

    Atmospheric samples were collected by high-volume air sampler and dust fall containers during the summer of 1995 at different sites in Amman City, Jordan. Heavy metal contents in settle able (dust fall) as well as in air particulates (suspended) were analyzed by graphite furnace atomic absorption spectrophotometry. The atmospheric concentrations of Zn, Cu, Pb, and Cd were 344, 170, 291, and 3.8 ng/m 3 , respectively. On the other hand, the levels of these elements in dust fall deposition were 505, 94, 74, and 3.1 μg/g, respectively. The fluxes and dry deposition velocities of these heavy metals were determined and compared with the findings of other investigators worldwide. Significant enrichment coefficients of heavy metals in dust fall were observed. The enrichment coefficients were 12.1, 6.1, 11.7, and 1.1 for Zn, Cu, Pb, and Cd, respectively

  8. Thermodynamic reversibility and irreversibility of the reverse transformation in stabilized Cu-Zn-Al martensite

    International Nuclear Information System (INIS)

    Kustov, S.; Corro, M.; Pons, J.; Cesari, E.; Van Humbeeck, J.

    2006-01-01

    It has been shown that both pinning- (mechanical) and reordering-induced (chemical) stabilization components contribute to the overall stabilization effect. An algorithm has been developed for quantitative analysis of the chemical and mechanical stabilization components, using routine calorimetry results. The basic idea underlying this algorithm is that chemical and mechanical stabilization components stem, respectively, from the factors, affecting thermodynamically reversible and irreversible factors during the first reverse transformation of the stabilized martensite. On a thermodynamical level, application of the suggested algorithm has been illustrated using experimental calorimetry results for a Cu-Zn-Al alloy. Here we report analysis of pinning and reordering processes on a microscopic scale, using experimental data on non-linear anelasticity in the same Cu-Zn-Al alloy to track different spatial and temporal localization of these processes during martensite ageing

  9. Adsorption and thermodynamic studies of Cu(II) and Zn(II) on organofunctionalized-kaolinite

    International Nuclear Information System (INIS)

    Guerra, Denis Lima; Airoldi, Claudio; Sousa, Kaline S. de

    2008-01-01

    Kaolinite-bearing clay samples from Perus, Sao Paulo state, Brazil, were used for chemical modification process with dimethyl sulfoxide and organofunctionalized with the silyating agent (RO) 3 Si(CH 2 ) 3 NH(CH 2 ) 2 NH 2 in the present study. The resulting material and natural kaolinite were subjected adsorpion process with Cu(II) and Zn(II) from aqueous solution at pH 6.0 and controlated temperature of 298 K. The Langmuir adsorption isotherm model has been applied to fit the experimental data. The results showed that the chemical modification process increases the basal spacing of the natural kaolinite from 0.711 to 0.955 nm. The energetic effects caused by Cu(II) and Zn(II) interactions were determined through calorimetric titration at the solid-liquid interface and gave a net thermal effect that enabled the calculation of the exothermic values and the equilibrium constant

  10. What is the band alignment of Cu2ZnSn(S,Se)4 solar cells?

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Hansen, Ole

    2017-01-01

    The band alignment at the Cu2ZnSn(S,Se)4/CdS solar cell heterojunction is a controversial issue, as different measurements and calculations point to substantially different conduction band offsets (CBO). As the actual value of the CBO has profound implications on solar cell performance, the aim...... of this work is to separate genuine process-dependent variations in the CBO from errors in its experimental determination. We argue that the two most likely mechanisms responsible for real CBO variations are Fermi level pinning (which tends to decrease the CBO) and chemical interdiffusion (which tends...... measurement approaches. Interestingly, a rough correlation can be established between the CBO measured at the Cu2ZnSnS4/CdS interface by different groups and their corresponding solar cell efficiency: lower-efficiency cells often have a large "cliff-like" offset, whereas most high-efficiency cells have...

  11. X-ray photoemission studies of Zn doped Cu1-xTl xBa2Ca2Cu 3-yZn yO10-δ (y = 0, 2.65) superconductors

    International Nuclear Information System (INIS)

    Khan, Nawazish A.; Mumtaz, M.; Ahadian, M.M.; Iraji-zad, Azam

    2007-01-01

    The X-ray photoemission (XPS) measurements of Cu 1-x Tl x Ba 2 Ca 2 Cu 3-y Zn y O 10-δ (y = 0, 2.65) superconductors have been performed and compared. These studies revealed that the charge state of thallium in the Cu 0.5 Tl 0.5 Ba 2 O 4-δ charge reservoir layer in Zn doped samples is Tl 1+ , while it is a mix of Tl 1+ and Tl 2+ in Zn free samples. The binding energy of Ba atoms in the Zn doped samples is shifted to higher energy, which when considered along with the presence of Tl 1+ suggested that it more efficiently directed the carriers to ZnO 2 and CuO 2 planes. The evidence of improved inter-plane coupling witnessed in X-ray diffraction is also confirmed by XPS measurements of Ca atoms in the Zn doped samples. The shift of the valance band spectrum in these Zn doped samples to higher energies suggested that the electrons at the top edge of the valance band were tied to a higher binding energy (relative to samples without Zn doping), which most likely resulted in a much lower energy state of the system in the superconducting state. The stronger superconducting state arising out of these effects is witnessed in the form of increased T c (R 0), J c and the extent of diamagnetism in the final compound

  12. Phase relations in the quasi-binary Cu{sub 2}GeS{sub 3}-ZnS and quasi-ternary Cu{sub 2}S-Zn(Cd)S-GeS{sub 2} systems and crystal structure of Cu{sub 2}ZnGeS{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Parasyuk, O.V. [Department of General and Inorganic Chemistry, Volyn State University, Voli Ave 13, 43009 Lutsk (Ukraine)]. E-mail: oleg@lab.univer.lutsk.ua; Piskach, L.V. [Department of General and Inorganic Chemistry, Volyn State University, Voli Ave 13, 43009 Lutsk (Ukraine); Romanyuk, Y.E. [Advanced Photonics Laboratory, Institute of Imaging and Applied Optics, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Olekseyuk, I.D. [Department of General and Inorganic Chemistry, Volyn State University, Voli Ave 13, 43009 Lutsk (Ukraine); Zaremba, V.I. [Department of Inorganic Chemistry, Ivan Franko National University of Lviv, 6 Kyryla and Mefodiya Str., 79005 L' viv (Ukraine); Pekhnyo, V.I. [V.I. Vernadskii Institute of General and Inorganic Chemistry, Ukrainian National Academy of Sciences, Palladina Ave 32-34, 03680 Kiev (Ukraine)

    2005-07-19

    The isothermal section of the Cu{sub 2}S-Zn(Cd)S-GeS{sub 2} systems at 670K was constructed using X-ray diffraction analysis. At this temperature, two quaternary intermediate phases, Cu{sub 2}CdGeS{sub 4} and {approx}Cu{sub 8}CdGeS{sub 7}, exist in the Cu{sub 2}S-CdS-GeS{sub 2} system, and only one phase, Cu{sub 2}ZnGeS{sub 4}, exists in the Cu{sub 2}S-ZnS-GeS{sub 2} system. The phase diagram of the Cu{sub 2}GeS{sub 3}-ZnS system was constructed using differential-thermal analysis and X-ray diffraction, and the existence of Cu{sub 2}ZnGeS{sub 4} has been confirmed. It forms incongruently at 1359K. Powder X-ray diffraction was used to refine the crystal structure of Cu{sub 2}ZnGeS{sub 4}, which crystallizes in the tetragonal stannite-type structure at 670K (space group I4-bar 2m, a=0.534127(9)nm, c=1.05090(2)nm, R{sub I}=0.0477). The possibility of the formation of quaternary compounds in the quasi-ternary systems A{sup I}{sub 2}X-B{sup II}X-C{sup IV}X{sub 2}, where A{sup I}-Cu, Ag; B{sup II}-Zn, Cd, Hg; C{sup IV}-Si, Ge, Sn and X-S, Se, Te is discussed.

  13. Zn and Cu isotopes as tracers of anthropogenic contamination in a sediment core from an urban lake

    Science.gov (United States)

    Thapalia, Anita; Borrok, David M.; Van Metre, Peter C.; Musgrove, MaryLynn; Landa, Edward R.

    2010-01-01

    In this work, we use stable Zn and Cu isotopes to identify the sources and timing of the deposition of these metals in a sediment core from Lake Ballinger near Seattle, Washington, USA. The base of the Lake Ballinger core predates settlement in the region, while the upper sections record the effects of atmospheric emissions from a nearby smelter and rapid urbanization of the watershed. δ66Zn and δ65Cu varied by 0.50‰ and 0.29‰, respectively, over the 500 year core record. Isotopic changes were correlated with the presmelter period (∼1450 to 1900 with δ66Zn = +0.39‰ ± 0.09‰ and δ65Cu = +0.77‰ ± 0.06‰), period of smelter operation (1900 to 1985 with δ66Zn = +0.14 ± 0.06‰ and δ65Cu = +0.94 ± 0.10‰), and postsmelting/stable urban land use period (post 1985 with δ66Zn = 0.00 ± 0.10‰ and δ65Cu = +0.82‰ ± 0.12‰). Rapid early urbanization during the post World War II era increased metal loading to the lake but did not significantly alter the δ66Zn and δ65Cu, suggesting that increased metal loads during this time were derived mainly from mobilization of historically contaminated soils. Urban sources of Cu and Zn were dominant since the smelter closed in the 1980s, and the δ66Zn measured in tire samples suggests tire wear is a likely source of Zn.

  14. Assessment of the genotoxicity of Cu and Zn in raw and anaerobically digested slurry with the Vicia faba micronucleus test

    OpenAIRE

    Marcato, Claire-Emmanuelle; Pinelli, Eric; Pourrut, Bertrand; Silvestre, Jérôme; Guiresse, Agnès Maritchù

    2009-01-01

    Genotoxicity of Cu and Zn was assessed by use of the micronucleus (MN) test on Vicia faba roots. Plants were exposed to various leachates of rawand anaerobically digested pig slurry, with maximum total concentrations of 200MCu and 600MZn. The results indicated stabilisation of the organic matter during anaerobic digestion of the slurry and bioconversion of some phytotoxic organic compounds (e.g. phenols or p-cresol), but did not showa relationship between Cu and Zn concentrations and MN fr...

  15. Effect of tellurium on machinability and mechanical property of CuAlMnZn shape memory alloy

    International Nuclear Information System (INIS)

    Liu Na; Li Zhou; Xu Genying; Feng Ze; Gong Shu; Zhu Lilong; Liang Shuquan

    2011-01-01

    Highlights: → A novel free-machining Cu-7.5Al-9.7Mn-3.4Zn-0.3Te (wt.%) shape memory alloy has been developed. → The size of dispersed particles with richer Te is 2-5 μm. → The CuAlMnZnTe alloy has good machinability which approached that of BZn15-24-1.5 due to the addition of Te. → Its shape memory property keeps the same as that of CuAlMnZn alloy with free Te. → The CuAlMnZn shape memory alloy with and without Te both have good ductile as annealed at 700 deg. C for 15 min. - Abstract: The microstructure transition, shape memory effect, machinability and mechanical property of the CuAlMnZn alloy with and without Te have been studied using X-ray diffraction analysis, chips observation and scanning electron microscopy (SEM), tensile strength test and differential scanning calorimeter (DSC), and semi-quantitative shape memory effect (SME) test. The particles with richer Te dispersedly distributed in grain interior and boundary with size of 2-5 μm. After the addition of Te, the CuAlMnZnTe alloy machinability has been effectively increased to approach that of BZn15-24-1.5 and its shape memory property remains the same as the one of CuAlMnZn alloy. The CuAlMnZn shape memory alloys with and without Te both have good ductility as annealed at 700 deg. C for 15 min.

  16. Ordered Phases in Cu2NiZn: A First-Principles Monte Carlo Study

    DEFF Research Database (Denmark)

    Simak, S.I.; Ruban, Andrei; Abrikosov, I.A.

    1998-01-01

    Monte Carlo simulations based on effective interactions obtained from first-principles calculations reveal the existence of three ordered phases in ternary Cu2NiZn: (i) "modified"-L1(0) (0-600 K), (ii) L1(2) (600-850 K), and (iii) L1(0) (850-1200 K). This is in contrast to the generally accepted...

  17. Transport properties of microwave sintered pure and glass added MgCuZn ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Madhuri, W., E-mail: madhuriw12@gmail.com [School of Advanced Sciences, VIT University, Vellore 632 014 (India); Penchal Reddy, M.; Kim, Il Gon [Department of Physics, Changwon National University, Changwon 641 773 (Korea, Republic of); Rama Manohar Reddy, N. [Department of Materials Science and Nanotechnology, Yogi Vemana University, Kadapa 516 227 (India); Siva Kumar, K.V. [Ceramic Composites Materials Laboratory, Sri Krishnadevaraya University, Anantapur 515 055 (India); Murthy, V.R.K. [Microwave Laboratory, IIT Madras, Chennai 600 036 (India)

    2013-07-01

    Highlights: • MgCuZn ferrite was successfully prepared by novel microwave sintering (MS) method. • The sintering temperature was notably reduced from 1150 °C to 950 °C for MS. • Temperature dependence of DC conductivity and AC conductivity are studied. • 1 wt% PBS glass added MS MgCuZn ferrite samples are suitable for core materials in multilayer chip inductors (MLCI). -- Abstract: A series of pure stoichiometric and 1 wt% lead borosilicate (PBS) glass added MgCuZn ferrite with the general formula Mg{sub 0.5}Cu{sub x}Zn{sub 0.5−x}Fe{sub 2}O{sub 4} with x = 0.05, 0.1, 0.15, 0.2, 0.25 and 0.3 were synthesized by microwave sintering technique. Single phase spinel structure is exhibited by the XRD patterns of these ferrites. DC and AC conductivity were investigated as a function of composition, temperature and frequency. DC conductivities were also estimated using the impedance spectroscopy analysis of Cole–Cole plots. The DC conductivities thus obtained are in good agreement with the experimental results. All the investigated samples exhibited two regions of conductivity one in the low temperature and the second in the high temperature region. It is observed that PBS glass added samples have lower conductivities than pure samples. Due to their lower conductivities and sintering temperatures the 1 wt% PBS glass added samples are suitable for multilayer chip inductor (MLCI) and high definition TV deflection yoke material application.

  18. Incorporation of trace elements in Portland cement clinker: Thresholds limits for Cu, Ni, Sn or Zn

    International Nuclear Information System (INIS)

    Gineys, N.; Aouad, G.; Sorrentino, F.; Damidot, D.

    2011-01-01

    This paper aims at defining precisely, the threshold limits for several trace elements (Cu, Ni, Sn or Zn) which correspond to the maximum amount that could be incorporated into a standard clinker whilst reaching the limit of solid solution of its four major phases (C 3 S, C 2 S, C 3 A and C 4 AF). These threshold limits were investigated through laboratory synthesised clinkers that were mainly studied by X-ray Diffraction and Scanning Electron Microscopy. The reference clinker was close to a typical Portland clinker (65% C 3 S, 18% C 2 S, 8% C 3 A and 8% C 4 AF). The threshold limits for Cu, Ni, Zn and Sn are quite high with respect to the current contents in clinker and were respectively equal to 0.35, 0.5, 0.7 and 1 wt.%. It appeared that beyond the defined threshold limits, trace elements had different behaviours. Ni was associated with Mg as a magnesium nickel oxide (MgNiO 2 ) and Sn reacted with lime to form a calcium stannate (Ca 2 SnO 4 ). Cu changed the crystallisation process and affected therefore the formation of C 3 S. Indeed a high content of Cu in clinker led to the decomposition of C 3 S into C 2 S and of free lime. Zn, in turn, affected the formation of C 3 A. Ca 6 Zn 3 Al 4 O 15 was formed whilst a tremendous reduction of C 3 A content was identified. The reactivity of cements made with the clinkers at the threshold limits was followed by calorimetry and compressive strength measurements on cement paste. The results revealed that the doped cements were at least as reactive as the reference cement.

  19. Pixe analysis of Cu,Zn,Hg and Cd in mussels samples in bay of Algiers

    International Nuclear Information System (INIS)

    Benamar, M.A.; Tchantchane, A.; Benouali, N.; Azbouche, A.; Tobbeche, S.

    1995-01-01

    The purpose of our work is the elaboration of and absolute technique for determination of trace elements in biological matrices by means of Pixe analysis. We are interested in the determination of heavy metals in mussels samples taken from differents sits of algies coast (Cu,Zn,Cd and Hg). The reason of our choise is the element toxicity and the possible contamination of the marine environment

  20. Determination of Cu, Fe, Zn Elements in Soil, Root Tea Plants, Tea Leaves, and Tea Beverage

    International Nuclear Information System (INIS)

    Supriyanto; Zainul-Kamal

    2006-01-01

    One of the causes of land quality damage was due to the pollution of Cu, Fe, and Zn so that it could directly and also indirectly cause the occurrence of pollution of plants which is growing on it for example tea plant that has been used by society for making of tea beverage. The sampling of soil, root tea plants, tea leaves and tea beverage samples were done in June, 2005 at sub district of Keparakan, Temanggung, Central Java. The purpose of research was to determine the content of Cu, Fe and Zn in soil, root tea plants, tea leaves and tea beverage. The research was done by digesting the sample with nitric acid until the clear solution was obtained, then it was added by aquabidest until 10.0 ml. Determination of Cu, Fe and Zn content used AAS instrument. The average concentration of Cu Fe and Zn obtained in deep soil samples area 0.155 ± 0.005 ppm, 127.16 ± 2.65 ppm, and 0.68 ± 0.02 ppm respectively, in surface soil samples are 0.355 ± 0.025 ppm, 360.59 ± 13.17 ppm and 0.78 ± 0.01 ppm respectively, in root of tea plants samples area 0.241 ± 0.098 ppm, 13.16 ± 1.34 ppm and 2.64 ± 0.06 ppm respectively, in tea leaves are 0.211 ± 0.013 ppm, 3.35 ± 0.886 ppm, and 0.795 ± 0.016 ppm respectively and in tea beverage 0.142 ± 0.086 ppm, 6.11 ± 0.35 ppm and 0.66 ± 0.02 ppm respectively. (author)

  1. The synthesis of higher alcohols using modified Cu/ZnO/Al@#2@#O@#3@# catalysts

    OpenAIRE

    Slaa, J.C.; Slaa, J.C.; van Ommen, J.G.; Ross, J.R.H.; Ross, J.R.H.

    1992-01-01

    This paper gives a review of research work in the synthesis of higher alcohols over catalysts based on Cu/ZnO/Al2O3, emphasizing three main topics: (i) the effect on selectivity of the addition of several compounds to this catalyst, (ii) the effect on selectivity of the reaction conditions used, and (iii) the reaction network leading to the different products found. Although the use of alkali compounds has been studied most extensively, other compounds, for example those containing manganese,...

  2. Self-Assembled Formation of Well-Aligned Cu-Te Nano-Rods on Heavily Cu-Doped ZnTe Thin Films

    Science.gov (United States)

    Liang, Jing; Cheng, Man Kit; Lai, Ying Hoi; Wei, Guanglu; Yang, Sean Derman; Wang, Gan; Ho, Sut Kam; Tam, Kam Weng; Sou, Iam Keong

    2016-11-01

    Cu doping of ZnTe, which is an important semiconductor for various optoelectronic applications, has been successfully achieved previously by several techniques. However, besides its electrical transport characteristics, other physical and chemical properties of heavily Cu-doped ZnTe have not been reported. We found an interesting self-assembled formation of crystalline well-aligned Cu-Te nano-rods near the surface of heavily Cu-doped ZnTe thin films grown via the molecular beam epitaxy technique. A phenomenological growth model is presented based on the observed crystallographic morphology and measured chemical composition of the nano-rods using various imaging and chemical analysis techniques. When substitutional doping reaches its limit, the extra Cu atoms favor an up-migration toward the surface, leading to a one-dimensional surface modulation and formation of Cu-Te nano-rods, which explain unusual observations on the reflection high energy electron diffraction patterns and apparent resistivity of these thin films. This study provides an insight into some unexpected chemical reactions involved in the heavily Cu-doped ZnTe thin films, which may be applied to other material systems that contain a dopant having strong reactivity with the host matrix.

  3. Study of Cu2O\\ZnO nanowires heterojunction designed by combining electrodeposition and atomic layer deposition

    Science.gov (United States)

    Makhlouf, Houssin; Weber, Matthieu; Messaoudi, Olfa; Tingry, Sophie; Moret, Matthieu; Briot, Olivier; Chtoutou, Radhouane; Bechelany, Mikhael

    2017-12-01

    Cu2O/ZnO nanowires (NWs) heterojunctions were successfully prepared by combining Atomic layer Deposition (ALD) and Electrochemical Deposition (ECD) processes. The crystallinity, morphology and photoconductivity properties of the Cu2O/ZnO nanostructures have been investigated. The properties of the Cu2O absorber layer and the nanostructured heterojunction were studied in order to understand the mechanisms lying behind the low photoconductivity measured. It has been found that the interface state defects and the high resistivity of Cu2O film were limiting the photovoltaic properties of the prepared devices. The understanding presented in this work is expected to enable the optimization of solar cell devices based on Cu2O/ZnO nanomaterials and improve their overall performance.

  4. Simultaneous determination of Hg, Pb, As, Cu, Zn and Ni in natural waters (with humic material) by energy dispersive X-ray fluorescence

    International Nuclear Information System (INIS)

    Morales S, E.A.; Zepeda L, E.

    1988-05-01

    Standardization of a method for simultaneous quantification of Hg, Pb, As, Cu, Zn and Ni in natural waters with humic acid contents was carried out. APDC for complexing free ions and silica gel as adsorber of metallic humates and further filtration were employed. X-ray fluorescence analysis was performed on filters. Good results were found for silica-gel as adsorber. Detection limits of 4 nanograms/milliliter were determined. (author)

  5. Effect of Freezing and Thawing on Activity of Cu and Zn in Black Soil of Northeast China Under Simulated Fertilization Using Pig Manure

    Directory of Open Access Journals (Sweden)

    XU Cong-long

    2015-06-01

    Full Text Available With the development of large-scale farms and the addition of Cu and Zn in feed additives, high Cu and Zn contents in feces of livestock and poultry occurred, and may cause soil pollution of the heavy metal especially Cu and Zn by livestock and poultry manure fertilization. Both fertilization of livestock and poultry manure and freeze-thaw action can alter the activity of heavy metals in soil, and furthermore change the environmental effect of heavy metals in soil. This paper aimed at the influence of freezing and thawing on the activities of Cu and Zn (exchangeable and carbonate in black soil of Northeast China under pig manure fertilization according to the northeast climate characteristics through laboratory simulation. The results showed that the contents of exchangeable Cu and Zn significantly increased and that of carbonate Cu and Zn slightly decreased under pig manure fertilization initial stage comparing with the control without fertilizer. The contents of exchangeable Cu and Zn slightly increased and that of carbonate Cu and Zn decreased for the higher fertilization comparing with lower fertilization. The contents of exchangeable Cu and Zn decreased and that of carbonate Cu and Zn significantly increased with the extension of fertilization time (one month compared with the early fertilization (one week. Moreover, the contents of exchangeable Cu and Zn under higher fertilization were all higher than that under lower fertilization, on the contrary, the contents of carbonate Cu and Zn under higher fertilization all were lower than that under lower fertilization. The contents of exchangeable and carbonate Cu and Zn all increased obviously with the freezing and thawing temperature decreased, and the contents of Cu and Zn for higher fertilization were higher than that for lower fertilization. In conclusion, the activities of Cu and Zn in black soil were disturbed by both pig manure with different fertilization amounts and fertilization

  6. Microstructure and Mechanical Properties of Al-10Zn-4.5Mg-xCu Turbine Impeller Produced by Investment Casting

    Directory of Open Access Journals (Sweden)

    Muhammad Syahid

    2017-03-01

    Full Text Available Aluminium alloy can be applied for a turbine impeller of Organic Rankine Cycle power plant that operates at temperatures below 150 oC. Aluminum turbine impeller can enhance efficiency of turbine due to light weight material. Al alloys was used for impeller due to good mechanical properties. Turbine impeller commonly produced by machining but which is time-consuming and less efficient because of material removal. . It can be replace by Investment casting to produce impeller turbine due to their complex geometry and precision. This study identifies effect Cu content of Al-9Zn-4Mg-xCu on the microstructure and mechanical properties of turbine impeller produce by investment casting. The study also identifies casting defect of turbine impeller. The structures consisted of α-Al, MgZn2, CuMgAl2 and CuAl2. Higher Cu content is the higher hardness value due to CuAl2 phase. Visual examination showed that the turbine impeller was free of macro defects and misruns

  7. Optical and Electrical Properties of TTF-MPcs (M = Cu, Zn Interfaces for Optoelectronic Applications

    Directory of Open Access Journals (Sweden)

    María Elena Sánchez-Vergara

    2015-11-01

    Full Text Available Sandwich structures were fabricated by a vacuum deposition method using MPc (M = Cu, Zn, with a Tetrathiafulvalene (TTF derivative, and Indium Tin Oxide (ITO and aluminum electrodes. The structure and morphology of the deposited films were studied by IR spectroscopy, scanning electron microscopy (SEM and energy dispersive spectroscopy (EDS. The absorption spectra of TTF derivative-MPc (M = Cu, Zn thin films deposited at room temperature were recorded in the spectral range 200–1000 nm. The optical band gap of the thin films was determined from the (αhν1/2 vs. hν plot. The direct-current (DC electrical properties of the glass/ITO/TTFderiv-MPc (M = Cu, Zn/Al structures were also investigated. Changes in conductivity of the derivative-TTF-enriched Pc compounds suggest the formation of alternative paths for carrier conduction. At low voltages, forward current density obeys an ohmic I-V relationship; at higher voltages, conduction is mostly due to a space-charge-limited conduction (SCLC mechanism.

  8. Removal of Cu (II and Zn (II from water with natural adsorbents from cassava agroindustry residues

    Directory of Open Access Journals (Sweden)

    Daniel Schwantes

    2015-07-01

    Full Text Available Current study employs solid residues from the processing industry of the cassava (Manihot esculenta Crantz (bark, bagasse and bark + bagasse as natural adsorbents for the removal of metal ions Cu(II and Zn(II from contaminated water. The first stage comprised surface morphological characterization (SEM, determination of functional groups (IR, point of zero charge and the composition of naturally existent minerals in the biomass. Further, tests were carried out to evaluate the sorption process by kinetic, equilibrium and thermodynamic studies. The adsorbents showed a surface with favorable adsorption characteristics, with adsorption sites possibly derived from lignin, cellulose and hemicellulose. The dynamic equilibrium time for adsorption was 60 min. Results followed pseudo-second-order, Langmuir and Dubinin-Radushkevich models, suggesting a chemisorption monolayer. The thermodynamic parameters suggested that the biosorption process of Cu and Zn was endothermic, spontaneous or independent according to conditions. Results showed that the studied materials were potential biosorbents in the decontamination of water contaminated by Cu(II and Zn(II. Thus, the above practice complements the final stages of the cassava production chain of cassava, with a new disposal of solid residues from the cassava agroindustry activity.

  9. EPR examination of Zn2+ and Cu2+ binding by pigmented soil fungi Cladosporium cladosporioides

    International Nuclear Information System (INIS)

    Buszman, Ewa; Pilawa, Barbara; Zdybel, Magdalena; Wilczynski, Slawomir; Gondzik, Anna; Witoszynska, Teresa; Wilczok, Tadeusz

    2006-01-01

    The purpose of this study was to examine the usefulness of electron paramagnetic resonance spectroscopy (EPR) to estimate zinc and copper ions biosorption from the environment by pigmented soil fungi Cladosporium cladosporioides. The existence of a low amount of pheomelanin, besides eumelanin, in C. cladosporioides samples was proved by the analysis of shape of their EPR spectra. Concentration of o-semiquinone free radicals in crude mycelium was 2.4 x 10 17 spin/g. Changes in free radicals system of C. cladosporioides cultured in the presence of Zn 2+ and Cu 2+ were analysed. Both magnetic and chemical interactions of zinc and copper ions with free radicals in C. cladosporioides melanin were found. Magnetically interacting diamagnetic Zn 2+ ions increased the concentration of o-semiquinone free radicals in melanin existing in C. cladosporioides mycelium, whereas paramagnetic Cu 2+ ions decreased this concentration. Chemical interactions of Zn 2+ and Cu 2+ ions decreased the free radical concentrations in C. cladosporioides melanin. Homogeneously distributed free radicals in C. cladosporioides melanin rise its activity in biosorption processes

  10. Thermomechanical cycling and two-way memory effect induced in Cu-Zn-Al

    International Nuclear Information System (INIS)

    Pons, J.

    1999-01-01

    The two-way shape memory effect (TWME) has been induced by thermomechanical cycling in Cu-Zn-Al alloys using a dedicated hydraulic mechanical testing soft machine with complete computer control of force, elongation and temperature. The results concerning single crystals (composition Cu-16.9 wt.% Zn-7.7 wt.% Al, nominal M s of 273 K) and polycrystals (Cu-15.8 wt.% Zn-8.3 wt.% Al, nominal M s of 230 K, mean grain size of 1 mm) are reported for two training protocols (sequence of one thermomechanical cycle of education followed by one stress free thermal cycle to check the TWME or twenty consecutive thermomechanical cycles followed by one or two checking thermal cycles). The capacity of the trained specimen for producing work under an antagonist compressive stress is also studied and the behaviour of the deformation of the specimen under such a condition at different temperatures is analysed in terms of a competition between the contributions of the different variants: trained variants with an intrinsic deformation in the direction of the tensile stress of the training process, trained variants with an intrinsic deformation which is not well orientated with respect to this direction (in the polycrystal) and new variants with an intrinsic deformation in the direction of the compressive stress which can replace the educated variants. (orig.)

  11. TRACE METAL CONTENT (Cu, Zn, Mn AND Fe) IN URTICA DIOICA L. AND PLANTAGO MAJOR L.

    Science.gov (United States)

    Krolak, Elzbieta; Raczuk, Jolanta; Borkowska, Lidia

    2016-11-01

    The aim of the study was to compare the contents of Cu, Zn, Mn and Fe in the washed and unwashed leaves and roots of two plant species: Urica dioica L. and Plantago major L., used in herbal medicine. These two herb species occur in the same environmental habitats, yet their morphological structure is different. The soil and plant samples for analyses were collected from an uncontaminated area in Eastern Poland. In each habitat location, the samples were taken from sandy soils with slightly acidic and neutral pH values. The obtained results showed that U. dioica and P. major accumulated similar amounts of trace metals, such as: Cu, Zn and Fe, in leaves, despite the differences in the morphological structure of their overground parts. The content of Mn in leaves U. dioica was about twice as much as in P. major. Also, no differences in the metal content were observed between washed and unwashed leaves of both species. However, in the same habitat conditions, a significantly higher content of Cu, Zn and Mn was found in the roots of P. major than U. dioica. The content of Fe in the roots was similar in both species. P. major and U. dioica may be a valuable source of microelements, if they are obtained from unpolluted habitats.

  12. Stress corrosion cracking and hydrogen embrittlement of an Al-Zn-Mg-Cu alloy

    International Nuclear Information System (INIS)

    Song, R.G.; Dietzel, W.; Zhang, B.J.; Liu, W.J.; Tseng, M.K.; Atrens, A.

    2004-01-01

    The age hardening, stress corrosion cracking (SCC) and hydrogen embrittlement (HE) of an Al-Zn-Mg-Cu 7175 alloy were investigated experimentally. There were two peak-aged states during ageing. For ageing at 413 K, the strength of the second peak-aged state was slightly higher than that of the first one, whereas the SCC susceptibility was lower, indicating that it is possible to heat treat 7175 to high strength and simultaneously to have high SCC resistance. The SCC susceptibility increased with increasing Mg segregation at the grain boundaries. Hydrogen embrittlement (HE) increased with increased hydrogen charging and decreased with increasing ageing time for the same hydrogen charging conditions. Computer simulations were carried out of (a) the Mg grain boundary segregation using the embedded atom method and (b) the effect of Mg and H segregation on the grain boundary strength using a quasi-chemical approach. The simulations showed that (a) Mg grain boundary segregation in Al-Zn-Mg-Cu alloys is spontaneous, (b) Mg segregation decreases the grain boundary strength, and (c) H embrittles the grain boundary more seriously than does Mg. Therefore, the SCC mechanism of Al-Zn-Mg-Cu alloys is attributed to the combination of HE and Mg segregation induced grain boundary embrittlement

  13. Formulation and Characterization of Cu Doped ZnO Thick Films as LPG Gas Sensor

    Directory of Open Access Journals (Sweden)

    A. V. PATIL

    2010-12-01

    Full Text Available Thick films of pure and various concentrations (1 wt. %, 3 wt. %, 5 wt. %, 7 wt. % and 10 wt. % of Cu-doped ZnO were prepared on alumina substrates using a screen printing technique. These films were fired at a temperature of 700ºC for two hours in an air atmosphere. Morphological, compositional and structural properties of the samples were obtained using the scanning electron microscopy (SEM, Energy dispersive spectroscopy (EDAX and X-ray diffraction techniques respectively. The LPG gas sensing properties of these thick films were investigated at different operating temperatures and LPG gas concentrations. The surface resistance of thick films decreases when exposed to LPG gas. The Cu doped films show significant sensitivity to LPG gas than pure ZnO film. 5 wt. % Cu-doped ZnO film was found to be more sensitive (87.3 % to LPG gas exposed at 300 oC than other doping concentrations with fast response and recovery time.

  14. Biochemical properties of Cu/Zn-superoxide dismutase from fungal strain Aspergillus niger 26

    Science.gov (United States)

    Dolashki, Aleksandar; Abrashev, Radoslav; Stevanovic, Stefan; Stefanova, Lilyana; Ali, Syed Abid; Velkova, Ludmila; Hristova, Rumyana; Angelova, Maria; Voelter, Wolfgang; Devreese, Bart; Van Beeumen, Jozef; Dolashka-Angelova, Pavlina

    2008-12-01

    The fungal strain Aspergillus niger produces two superoxide dismutases, Cu/Zn-SOD and Mn-SOD. The primary structure of the Cu/Zn-SOD has been determined by Edman degradation of peptide fragments derived from proteolytic digests. A single chain of the protein, consisting of 153 amino acid residues, reveals a very high degree of structural homology with the amino acid sequences of other Aspergillus Cu/Zn-SODs. The molecular mass of ANSOD, measured by MALDI-MS and ESI-MS, and calculated by its amino acid sequence, was determined to be 15 821 Da. Only one Trp residue, at position 32, and one disulfide bridge were identified. However, neither a Tyr residue nor a carbohydrate chain occupying an N-linkage site (-Asn-Ile-Thr-) were found. Studies on the temperature and pH dependence of fluorescence, and on the temperature dependence of CD spectroscopic properties, confirmed that the enzyme is very stable, which can be explained by the stabilising effect of the disulfide bridge. The enzyme retains about 53% of its activity after incubation for a period of 30 min at 60 °C, and 15% at 85 °C.

  15. Catalytic activity of mono and bimetallic Zn/Cu/MWCNTs catalysts for the thermocatalyzed conversion of methane to hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Erdelyi, B. [Department of Physical Chemistry, Faculty of Science, P.J. Šafárik University, Moyzesova 11, 041 54 Košice (Slovakia); Institute of Physics, Faculty of Science, P.J. Šafárik University, Park Angelium 9, 040 01 Košice (Slovakia); Oriňak, A., E-mail: andrej.orinak@upjs.sk [Department of Physical Chemistry, Faculty of Science, P.J. Šafárik University, Moyzesova 11, 041 54 Košice (Slovakia); Oriňaková, R. [Department of Physical Chemistry, Faculty of Science, P.J. Šafárik University, Moyzesova 11, 041 54 Košice (Slovakia); Lorinčík, J. [Research Center Rez, Hlavní 130, 250 68 Husinec-Řež (Czech Republic); Jerigová, M. [Department of Physical Chemistry, Comenius University, Mlynská dolina 842 15 Bratislava 4 (Slovakia); Velič, D. [Department of Physical Chemistry, Comenius University, Mlynská dolina 842 15 Bratislava 4 (Slovakia); International Laser Centre, Ilkovičová 3, 841 01 Bratislava (Slovakia); Mičušík, M. [Polymer institute, Slovak Academy of Sciences, Dubravská cesta 9, 84541 Bratislava (Slovakia); and others

    2017-02-28

    Highlights: • Zn/Cu/MWCNTs catalyst with good activity. • Methane conversion to hydrogen with high effectivity. • ZnO/Cu responsible for catalytic activity. - Abstract: Mono and bimetallic multiwalled carbon nanotubes (MWCNTs) fortified with Cu and Zn metal particles were studied to improve the efficiency of the thermocatalytic conversion of methane to hydrogen. The surface of the catalyst and the dispersion of the metal particles were studied by scanning electron microscopy (SEM), secondary ion mass spectrometry (SIMS) and with energy-dispersive X-ray spectroscopy (EDS). It was confirmed that the metal particles were successfully dispersed on the MWCNT surface and XPS analysis showed that the Zn was oxidised to ZnO at high temperatures. The conversion of methane to hydrogen during the catalytic pyrolysis was studied by pyrolysis gas chromatography using different amounts of catalyst. The best yields of hydrogen were obtained using pyrolysis conditions of 900 °C and 1.2 mg of Zn/Cu/MWCNT catalyst for 1.5 mL of methane.The initial conversion of methane to hydrogen obtained with Zn/Cu/MWCNTs was 49%, which represent a good conversion rate of methane to hydrogen for a non-noble metal catalyst.

  16. Comparison of Antibacterial Effects of ZnO and CuO Nanoparticles Coated Brackets against Streptococcus Mutans.

    Science.gov (United States)

    Ramazanzadeh, Baratali; Jahanbin, Arezoo; Yaghoubi, Masoud; Shahtahmassbi, Nasser; Ghazvini, Kiarash; Shakeri, Mohammadtaghi; Shafaee, Hooman

    2015-09-01

    During the orthodontic treatment, microbial plaques may accumulate around the brackets and cause caries, especially in high-risk patients. Finding ways to eliminate this microbial plaque seems to be essential. The aim of this study was to compare the antibacterial effects of nano copper oxide (CuO) and nano zinc oxide (ZnO) coated brackets against Streptococcus mutans (S.mutans) in order to decrease the risk of caries around the orthodontic brackets during the treatment. Sixty brackets were coated with nanoparticles of ZnO (n=20), CuO (n=20) and CuO-ZnO (n=20). Twelve uncoated brackets constituted the control group. The brackets were bonded to the crowns of extracted premolars, sterilized and prepared for antimicrobial tests (S.mutans ATCC35668). The samples taken after 0, 2, 4, 6 and 24 hours were cultured on agar plates. Colonies were counted 24 hours after incubation. One-way ANOVA and Tukey tests were used for statistical analysis. In CuO and CuO-ZnO coated brackets, no colony growth was seen after two hours. Between 0-6 hours, the mean colony counts were not significantly different between the ZnO and the control group (p>0.05). During 6-24 hours, the growth of S.mutans was significantly reduced by ZnO nanoparticles in comparison with the control group (pbrackets have better antimicrobial effect on S.mutans than ZnO coated brackets.

  17. Response of Pinus halepensis Mill. seedlings to biosolids enriched with Cu, Ni and Zn in three Mediterranean forest soils

    International Nuclear Information System (INIS)

    Fuentes, David; Disante, Karen B.; Valdecantos, Alejandro; Cortina, Jordi; Ramon Vallejo, V.

    2007-01-01

    We investigated the response of Pinus halepensis seedlings to the application of biosolids enriched with Cu, Ni and Zn on three Mediterranean forest soils under semiarid conditions. One-year-old seedlings were planted in lysimeters on soils developed from marl, limestone and sandstone which were left unamended, amended with biosolids, or amended with biosolids enriched in Cu, Ni and Zn. Enriched biosolids increased plant heavy metal concentration, but always below phytotoxic levels. Seedlings receiving unenriched biosolids showed a weak reduction in Cu and Zn concentration in needles, negatively affecting physiological status during drought. This effect was alleviated by the application of enriched sludge. Sewage sludge with relatively high levels of Cu, Zn and Ni had minor effects on plant performance on our experimental conditions. Results suggest that micronutrient limitations in these soils may be alleviated by the application of biosolids with a higher Cu, Zn and Ni content than those established by current regulations. - Biosolid-borne Cu, Ni and Zn did not show negative effects on Pinus halepensis seedlings performance after application on three Mediterranean forest soils

  18. Interactions of Cu-substrates with titanium-alloyed Sn-Zn solders

    Directory of Open Access Journals (Sweden)

    Soares D.

    2006-01-01

    Full Text Available The interactions of copper substrate with titanium-alloyed Sn-Zn eutectic solders have been studied. Two series of experiments have been performed. The first one consisted in differential thermal analyses of Sn-Zn nearly eutectic alloys containing from 1.3 to 2.2 wt. % Ti. Diffusion couples consisted of Cu-wires and Sn-Zn-Ti liquid solders, produced at 250 and 275 OC have been prepared in the second series,. The contact times were up to 3600 s. The contact zones have been characterized by optical and scanning electron microscope. Two layers have been found along the interfaces solid/liquid. The first and the second layers are identical, respectively, with γ and ε phases of the Cu-Zn system. No changes of the chemical compositions were detected for the tested temperatures and reaction times. Continuous parabolic growth of the total diffusion zone thickness with the time of diffusion is observed. The growth is due mainly to one the formed layers (γ while the thickness of the ε-phase layer, stays almost constant for all tested diffusion times and temperatures.

  19. Reaction of intermetallic compounds of the ScT composition (T=Ag, Cu, Zn, Ni) with hydrogen

    International Nuclear Information System (INIS)

    Shilkin, S.P.; Volkova, L.S.; Tarasov, B.P.

    1995-01-01

    Reaction of intermetallic compounds of ScT composition (T=Ag, Cu, Zn, Ni), crystallized in CsCl structural type, with hydrogen at 0.2-10 MPa pressure and 293-673 K temperature is studied by chemical, x-ray phase and complex thermogravimetry analysis methods. It is shown that under such conditions hydrogen absorption by ScAg and ScCu is accompanied by the decay of their source matrices into scandium dihydride and metal silver and copper respectively. For ScZn a fine-dispersion mixture of scandium dihydride with zinc and hydride phase of a new zinc-containing intermetallic compound appears to be the finite reaction product. In case of ScNi a hydride phase of ScNiH 2.6 composition is produced, which is crystallized in a rhombic syngony with the lattice periods: a=0.5281±0.0007, b=0.7393±0.0009 and c=0.3327±0.0004 nm. 9 refs.; 2 tabs

  20. High-sensitivity determination of Zn(II) and Cu(II) in vitro by fluorescence polarization

    Science.gov (United States)

    Thompson, Richard B.; Maliwal, Badri P.; Feliccia, Vincent; Fierke, Carol A.

    1998-04-01

    Recent work has suggested that free Cu(II) may play a role in syndromes such as Crohn's and Wilson's diseases, as well as being a pollutant toxic at low levels to shellfish and sheep. Similarly, Zn(II) has been implicated in some neural damage in the brain resulting from epilepsy and ischemia. Several high sensitivity methods exist for determining these ions in solution, including GFAAS, ICP-MS, ICP-ES, and electrochemical techniques. However, these techniques are generally slow and costly, require pretreatment of the sample, require complex instruments and skilled personnel, and are incapable of imaging at the cellular and subcellular level. To address these shortcomings we developed fluorescence polarization (anisotropy) biosensing methods for these ions which are very sensitivity, highly selective, require simple instrumentation and little pretreatment, and are inexpensive. Thus free Cu(II) or Zn(II) can be determined at picomolar levels by changes in fluorescence polarization, lifetime, or wavelength ratio using these methods; these techniques may be adapted to microscopy.

  1. Selenization of mixed metal oxides for dense and ZnSe-free Cu{sub 2}ZnSnSe{sub 4} absorber films

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Yitao; Chen, Guilin; Pan, Bin; Li, JianMin; Jiang, Guoshun; Liu, Weifeng, E-mail: liuwf@ustc.edu.cn; Zhu, Changfei, E-mail: cfzhu@ustc.edu.cn

    2014-04-05

    Highlights: • ZnSe-free CZTSe films with large grains was prepared from mixed oxides nanopraticles. • Appearance of Zn{sub 2}SnO{sub 4} in mixed oxides precursors leads to the absence of ZnSe secondary phrase. • To obtain pure CZTSe phase, different treating temperature was used. -- Abstract: Cu{sub 2}ZnSnSe{sub 4} (CZTSe) films were prepared by direct selenization of Cu{sub 2}O, SnO{sub 2} and Zn{sub 2}SnO{sub 4} precursors. Oxides precursors were prepared by baking hydroxides precipitation. In order to obtain ZnSe-free CZTSe films, Zn{sub 2}SnO{sub 4} was used to replace separated ZnO and SnO{sub 2} as one of the precursors. Through X-ray diffraction (XRD), scanning electron microscopy (SEM), it was found that CZTSe films, with micron-sized dense grains, were obtained in our work. From Raman spectra, it was also found that the ZnSe secondary phase was absent after the selenization. An energy bandgap about 0.86 eV was obtained in our work, which confirmed the Stannite-CZTSe structure.

  2. Cu2ZnSnS4 thin films grown by flash evaporation and subsequent annealing in Ar atmosphere

    International Nuclear Information System (INIS)

    Caballero, R.; Izquierdo-Roca, V.; Merino, J.M.; Friedrich, E.J.; Climent-Font, A.; Saucedo, E.; 2UB, Departament d'Electrònica, Universitat de Barcelona, C. Martí i Franquès 1, E-08028 Barcelona (Spain))" data-affiliation=" (IREC, Catalonia Institute for Energy Research, C. Jardins de les Dones de Negre 1, Sant Adriá del Besòs, E-08930 Barcelona (Spain); IN2UB, Departament d'Electrònica, Universitat de Barcelona, C. Martí i Franquès 1, E-08028 Barcelona (Spain))" >Pérez-Rodríguez, A.; León, M.

    2013-01-01

    A study of Cu 2 ZnSnS 4 thin films grown by flash evaporation and subsequently annealed in Ar atmosphere has been carried out. Prior to thin film deposition, Cu 2 ZnSnS 4 bulk compounds with stoichiometric and Zn-rich compositions were synthesized as evaporation sources. The characteristics of the bulk compounds and thin films were investigated by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and elastic back scattering. Cu 2 ZnSnS 4 deposited films contain lower concentrations of Zn than the bulk compounds used as evaporation sources, which is related to a preferential Zn re-evaporation during the deposition process. The desired kesterite composition for solar cell applications was achieved by using a Zn-rich compound as the evaporation source plus a thermal treatment at 620 °C in Ar atmosphere. - Highlights: ► Cu 2 ZnSnS 4 (CZTS) thin films by flash evaporation + annealing in Ar atmosphere ► Difficulty of growing a single phase kesterite material ► X-ray diffraction and Raman spectroscopy to identify the different phases ► Importance of the starting film composition to get the desired CZTS material ► Annealing treatment to obtain the optimum material to be used for CZTS solar cells

  3. Processing–microstructure–properties relationship in a CuNiZn ferrite

    International Nuclear Information System (INIS)

    Clausell, C.; Barba, A.

    2018-01-01

    CuNiZn ferrites are polycrystalline ceramic materials that are used widely in electronic devices for a number of reasons, including their high permeability in the RF frequency region, electrical resistivity, mechanical hardness and chemical stability. One of their main applications is in the production of specimens to prevent possible interferences between electronic devices, thanks to their ability to absorb electromagnetic waves. However, their electromagnetic properties are not solely dependent on their chemical composition, but also on the microstructure of the final piece (relative density or total porosity, grain size distribution, pore size distribution, the nature of the grain boundary, presence of secondary phases, dopants, etc.) and, therefore, on the morphology and size of the starting particles, and the processing method. The microstructure of the sintered specimens was designed in such a way as to optimize the electromagnetic properties of this ferrite. The solid-state sintering stage was also modeled with this optimization in mind. This sintering model enabled to propose the material transport mechanisms that controlled the densification and grain-growth rates, as well as the relative rates of these two simultaneous processes. The established relationships facilitate the design of a thermal cycle suitable for the manufacture of ferrite pieces with maximum relative density and the necessary microstructure. Together with the pre-configured chemical composition, the idea is that this ensures a strong set of final electromagnetic properties. The electromagnetic properties of the sintered ferrites were observed to improve as sintered relative density and average grain size increased, provided there was no evidence of exaggerated grain growth. In this sense, it seems there is a threshold of the grain size as of which the electromagnetic properties of the sintered specimens get worse. A linear relationship was observed between the imaginary part of the

  4. The competing roles of i-ZnO in Cu(ln,Ga)Se¬2 solar cells

    NARCIS (Netherlands)

    Williams, B.L.; Zardetto, V.; Kniknie, B.J.; Verheijen, M.A.; Kessels, W.M.M.; Creatore, M.

    2016-01-01

    The electrical role of the highly resistive and transparent (HRT) i-ZnO layer in Cu(In, Ga)Se2(CIGS) solar cells is investigated. By tuning the resistivity of atomic layer deposited (ALD) i-ZnO through the use of post-growth O2-plasma treatments, it is shown that low i-ZnO carrier densities (i.e.

  5. The competing roles of i-ZnO in Cu(In,Ga)Se2 solar cells

    NARCIS (Netherlands)

    Williams, B.L.; Zardetto, V.; Kniknie, B.; Verheijen, M.A.; Kessels, W.M.M.; Creatore, M.

    2016-01-01

    The electrical role of the highly resistive and transparent (HRT) i-ZnO layer in Cu(In, Ga)Se2(CIGS) solar cells is investigated. By tuning the resistivity of atomic layer deposited (ALD) i-ZnO through the use of post-growth O2-plasma treatments, it is shown that low i-ZnO carrier densities (i.e.

  6. Cu2ZnSn(S,Se)4 from CuxSnSy nanoparticle precursors on ZnO nanorod arrays

    International Nuclear Information System (INIS)

    Kavalakkatt, Jaison; Lin, Xianzhong; Kornhuber, Kai; Kusch, Patryk; Ennaoui, Ahmed; Reich, Stephanie; Lux-Steiner, Martha Ch.

    2013-01-01

    Solar cells with Cu 2 ZnSnS 4 absorber thin films have a potential for high energy conversion efficiencies with earth-abundant and non-toxic elements. In this work the formation of CZTSSe from Cu x SnS y nanoparticles (NPs) deposited on ZnO nanorod (NR) arrays as precursors for zinc is investigated. The NPs are prepared using a chemical route and are dispersed in toluene. The ZnO NRs are grown on fluorine doped SnO 2 coated glass substrates by electro deposition method. A series of samples are annealed at different temperatures between 300 °C and 550 °C in selenium containing argon atmosphere. To investigate the products of the reaction between the precursors the series is analyzed by means of X-ray diffraction (XRD) and Raman spectroscopy. The morphology is recorded by scanning electron microscopy (SEM) images of broken cross sections. The XRD measurements and the SEM images show the disappearing of ZnO NRs with increasing annealing temperature. Simultaneously the XRD and Raman measurements show the formation of CZTSSe. The formation of secondary phases and the optimum conditions for the preparation of CZTSSe is discussed. - Highlights: ► Cu x SnS y nanoparticles are deposited on ZnO nanorod arrays. ► Samples are annealed at different temperatures (300–550 °C) in Se/Ar-atmosphere. ► Raman spectroscopy, X-ray diffraction and electron microscopy are performed. ► ZnO disappears with increasing annealing temperature. ► With increasing temperature Cu x SnS y and ZnO form Cu 2 ZnSn(S,Se) 4

  7. High Pressure Properties of a Ba-Cu-Zn-P Clathrate-I

    Directory of Open Access Journals (Sweden)

    Juli-Anna Dolyniuk

    2016-08-01

    Full Text Available The high pressure properties of the novel tetrel-free clathrate, Ba8Cu13.1Zn3.3P29.6, were investigated using synchrotron powder X-ray diffraction. The pressure was applied using a diamond anvil cell. No structural transitions or decomposition were detected in the studied pressure range of 0.1–7 GPa. The calculated bulk modulus for Ba8Cu13.1Zn3.3P29.6 using a third-order Birch-Murnaghan equation of state is 65(6 GPa at 300 K. This bulk modulus is comparable to the bulk moduli of Ge- and Sn-based clathrates, like A8Ga16Ge30 (A = Sr, Ba and Sn19.3Cu4.7P22I8, but lower than those for the transition metal-containing silicon-based clathrates, Ba8TxSi46−x, T = Ni, Cu; 3 ≤ x ≤ 5.

  8. The effect of Cu on mechanical and precipitation properties of Al-Zn-Mg alloys

    International Nuclear Information System (INIS)

    Chinh, N.Q.; Lendvai, J.; Ping, D.H.; Hono, K.

    2004-01-01

    The effect of Cu on the mechanical and precipitation properties of a high strength Al-2.4 at.% Zn-2.1 at.% Mg alloy was investigated by compression and indentation tests, as well as by differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and three-dimensional atom probe field ion microscopy (3DAPFIM). The addition of 0.5 at.% Cu introduces significant changes in the precipitation process and consequently in the age-hardening behavior of the alloy. Microstructural measurements reveal that the addition of Cu changes the density of GP zones, but it also changes partly the shape and composition of the particles. Mechanical and microstructural results together lead to the conclusion that clustering of solute atoms and vacancies during or immediately after water quenching plays an important role in the nucleation of intermediate phase precipitates in one-step aging and the addition of Cu to ternary Al-Zn-Mg leads to changes also in the initial clustering process

  9. The optoelectronic properties and role of Cu concentration on the structural and electrical properties of Cu doped ZnO nanoparticles

    Science.gov (United States)

    Omri, K.; Bettaibi, A.; Khirouni, K.; El Mir, L.

    2018-05-01

    In the current study, we synthesized a Cu-doped ZnO (CZO) nanoparticles material using a sol-gel method with different doping concentrations of Cu (0, 2, 3 and 4 at.%). The control of the Cu concentration on structural, electrical and optical properties of CZO nanoparticles was investigated in detail. The XRD analysis of the CZO nanoparticles reveals the formation of ZnO hexagonal wurtzite structure for all samples which confirm the incorporation of Cu2+ ions into the ZnO lattice by substitution. Furthermore, CZO nanoparticles showed a small red shift of absorption band with the incorporation of Cu from 0 to 4 at.%; i.e. a decreased band gap value from 3.34 eV to 3.27 eV with increasing of Cu doping content. The frequency dispersion of the electric conductivity were studied using the Jonscher universal power law, according to relation σ(ω) = σDC + A ωs(T). Alternative current conductivity increases with increasing Cu content in spite of the decrease the activation energy with copper loading. It was found that the conductivity reached its maximum value for critical Cu concentration of 3 at.%. The frequency relaxation phenomenon was also investigated and all results were discussed in term of the copper doping concentration.

  10. Unusual hardening behaviour in heavily cryo-rolled Cu-Al-Zn alloys during annealing treatment

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Y.L. [Faculty of Science, Kunming University of Science and Technology, Kunming 650500 (China); Ren, S.Y. [Ningbo Powerway Alloy Material Co., Ltd, Ningbo 315135 (China); Zeng, S.D. [Yunnan Institute of Measuring and Testing Technology, Kunming 650228 (China); Zhu, X.K., E-mail: xk_zhu@hotmail.com [Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650500 (China)

    2016-04-06

    Three nanostructured Cu-Al-Zn alloys were produced via rolling at the liquid nitrogen temperature. The deformed Cu alloys were then annealed at 150–300 °C for 1 h. The two alloys with high solute content and thus with low stacking fault energy exhibit unusual annealing hardening, namely, an increase in hardness and strength and a decrease in tensile elongation after annealing at 150 and 200 °C. From X-ray diffraction (XRD) analysis and microstructural observations by transmission electron microscopy (TEM), it is found that microstrain and dislocation density decrease after annealing at 200 °C because of the recovery of dislocations and the lattice parameter decreases due to solute segregation. Meanwhile, the twin density of the two Cu alloys increases and grain size remains basically unchanged. It is shown that the formation of annealing twins and stacking faults and the segregation of solute atoms may be the main causes of unusual annealing hardening.

  11. Thermal and Microstructure Characterization of Zn-Al-Si Alloys and Chemical Reaction with Cu Substrate During Spreading

    Science.gov (United States)

    Berent, Katarzyna; Pstruś, Janusz; Gancarz, Tomasz

    2016-08-01

    The problems associated with the corrosion of aluminum connections, the low mechanical properties of Al/Cu connections, and the introduction of EU directives have forced the potential of new materials to be investigated. Alloys based on eutectic Zn-Al are proposed, because they have a higher melting temperature (381 °C), good corrosion resistance, and high mechanical strength. The Zn-Al-Si cast alloys were characterized using differential scanning calorimetry (DSC) measurements, which were performed to determine the melting temperatures of the alloys. Thermal linear expansion and electrical resistivity measurements were performed at temperature ranges of -50 to 250 °C and 25 to 300 °C, respectively. The addition of Si to eutectic Zn-Al alloys not only limits the growth of phases at the interface of liquid solder and Cu substrate but also raises the mechanical properties of the solder. Spreading test on Cu substrate using eutectic Zn-Al alloys with 0.5, 1.0, 3.0, and 5.0 wt.% of Si was studied using the sessile drop method in the presence of QJ201 flux. Spreading tests were performed with contact times of 1, 8, 15, 30, and 60 min, and at temperatures of 475, 500, 525, and 550 °C. After cleaning the flux residue from solidified samples, the spreadability of Zn-Al-Si on Cu was determined. Selected, solidified solder/substrate couples were cross-sectioned, and the interfacial microstructures were studied using scanning electron microscopy and energy dispersive x-ray spectroscopy. The growth of the intermetallic phase layer was studied at the solder/substrate interface, and the activation energy of growth of Cu5Zn8, CuZn4, and CuZn phases were determined.

  12. The effect of Cu-rich sub-layer on the increased corrosion resistance of Cu-xZn alloys in chloride containing borate buffer

    International Nuclear Information System (INIS)

    Milosev, Ingrid; Mikic, Tadeja Kosec; Gaberscek, Miran

    2006-01-01

    The electrochemical behaviour of Cu-xZn alloys, as well as their constituent metals, in a borate buffer containing chloride ions in the molar range from 0.01 to 1 M are studied. Characteristics of these materials under anodic polarization are compared and the composition and morphology of the corrosion products formed in the course of polarization experiment are analysed by SEM and EDS. X-ray photoelectron spectroscopy and electrochemical impedance measurements are used for characterization of the surface layers formed on Cu, Zn and Cu-40Zn alloy during 2-h immersion at E oc in a borate buffer containing two different concentrations of chloride ions. New aspects of the behaviour of brass under E oc condition are revealed. The improved corrosion resistance of brass in chloride media, if compared to zinc metal, is attributed to a Cu-rich layer formed by the selective dissolution of zinc. Based on the results, a structural model describing the improved corrosion resistance of Cu-40Zn alloy with respect to Zn metal is proposed

  13. Spectral features and antibacterial properties of Cu-doped ZnO nanoparticles prepared by sol-gel method

    Science.gov (United States)

    Alireza, Samavati; A, F. Ismail; Hadi, Nur; Z, Othaman; M, K. Mustafa

    2016-07-01

    Zn1-x Cu x O (x = 0.00, 0.01, 0.03, and 0.05) nanoparticles are synthesized via the sol-gel technique using gelatin and nitrate precursors. The impact of copper concentration on the structural, optical, and antibacterial properties of these nanoparticles is demonstrated. Powder x-ray diffraction investigations have illustrated the organized Cu doping into ZnO nanoparticles up to Cu concentration of 5% (x = 0.05). However, the peak corresponding to CuO for x = 0.01 is not distinguishable. The images of field emission scanning electron microscopy demonstrate the existence of a nearly spherical shape with a size in the range of 30-52 nm. Doping Cu creates the Cu-O-Zn on the surface and results in a decrease in the crystallite size. Photoluminescence and absorption spectra display that doping Cu causes an increment in the energy band gap. The antibacterial activities of the nanoparticles are examined against Escherichia coli (Gram negative bacteria) cultures using optical density at 600 nm and a comparison of the size of inhibition zone diameter. It is found that both pure and doped ZnO nanoparticles indicate appropriate antibacterial activity which rises with Cu doping. Project supported by the Universiti Teknologi Malaysia (UTM) (Grant No. R. J1300000.7809.4F626). Dr. Samavati is thankful to RMC for postdoctoral grants.

  14. The effects of Zn doping on magnetic properties of Cu3Bi(SeO3)2O2Cl

    Science.gov (United States)

    Yang, Pei-Ying; Tseng, Wu-Jyun; Wu, Hung-Cheng; Kakarla, D. Chandrasekhar; Yang, Hung-Duen; Department of Physics, Natl Sun Yat Sen Univ Team

    Recently, layered spin-frustrated Cu3Bi(SeO3)2 O2Cl has received considerable research attention due to its unusual magnetic properties. Two inequivalent Cu2 + ions form a pseudo-kagome lattice that invokes spin frustration and anisotropic magnetic properties. In this study, the influence of Zn doping on the complex magnetic properties has been explored. Polycrystalline (Cu1-xZnx) Bi(SeO3)2 O2Cl (0 x 0.5) samples were synthesized using solid-state reaction and characterized by X-ray diffraction and magnetic measurements. The Zn doping strongly modulates the magnetic ground state of the system. The antiferromagnetic transition temperature TN = 24 K and magnetic field-induced hysteresis observed for x = 0 at low field are systematically shifted to lower temperature and reduced with Zn doping. These results can illustrate the insight of the occurrence of field-induced spin-flip type multiferroics in Cu3Bi(SeO3)2 O2Cl.

  15. Fusion and characterization of an alloy Cu-Zn-Al-Ni of nuclear interest

    International Nuclear Information System (INIS)

    Santana M, J.S.

    2003-01-01

    The present work is the result of the study of a non ferrous quatenary alloy of Cu-Zn-Al-Ni (Foundry 3), it was chosen of a series of alloys to obtain so much information of its microstructural properties like mechanical, evaluating them and comparing them with the previously obtained ternary alloys of Cu-AI-Ni (Foundry 1) and Cu-Zn-AI (Foundry 2) identified as alloys of memory effect and superalloys. These were carried out starting from the foundry of their pure elements of Cu, Zn, Al, Ni. When physically having the ingot of each alloy, different techniques were used for their characterization. The used techniques were through the metallographic analysis, by scanning electron microscopy (SEM), X-ray dispersive energy spectroscopy (EDS), X-ray diffraction (XRD), mechanical essays and Rockwell hardness. The non ferrous quaternary alloy Cu-Zn-AI-Ni by means of the metallographic analysis didn't show significant differences in their three sections (superficial, longitudinal and transverse) since result an homogeneous alloy at the same that the both ternaries. The grain size of the quaternary alloy is the finest while the ternary alloy of Cu-AI-Ni is the one that obtained the biggest grain size. Through MEB together with the analysis by EDS and the mapping of the elements that constitute each alloy, show that the three foundries were alloyed, moreover the presence of aggregates was also observed in the Foundries 2 and 3. These results by means of the analysis of XRD corroborate that these alloys have more of two elements. Relating the microstructural properties with those mechanical show us that as minor was the grain size, better they were his mechanical properties, in this case that of the quaternary alloy. With regard to the test of Rockwell hardness the Foundry 1 were the softest with the temper treatment, while that the Foundries 2 and 3 were the hardest with this same treatment, being still harder the Foundry 2 but with very little difference, for what great

  16. Synthesis and luminescent properties of novel Cu (II), Zn (II ...

    Indian Academy of Sciences (India)

    Administrator

    solid state respectively, and the maximum wavelengths of the polymeric complexes 2 and 3 are red ... properties of inorganic and organic small molecule ... good electro- and photo-active properties. ... solution was poured over 600 mL of ice water and ... Extraction with ..... atom and carbon atom in the phenanthroline and.

  17. The chemisorption and reactions of formic acid on Cu films on ZnO (000 overline1)-O

    Science.gov (United States)

    Ludviksson, A.; Zhang, R.; Campbell, Charles T.; Griffiths, K.

    1994-06-01

    The adsorption and reactions of formic acid (HCOOD : HCOOH = 3:1) on the oxygen-terminated ZnO(0001¯)-O surface and on thin Cu films deposited on the ZnO(0001¯)-O surface have been studied with temperature programmed desorption (TPD) and XPS. Small amounts of formic acid dissociate at defect sites on clean ZnO(0001¯)-O to yield surface formate (HCOO). The acid D(H) from this dissociation does not reappear in TPD, and is lost to the ZnO bulk, as confirmed by nuclear reaction analysis. The surface HCOO decomposes to yield nearly simultaneous CO 2 (37%), CO (63%) and H 2 TPD peaks at 560 K. Substantial amounts of D (˜ 20%) are incorporated in this hydrogen TPD peak resulting from formate decomposition at ZnO defects, indicating that bulk D is readily accessible. Submonolayer and multilayer Cu films that are deposited at 130 K and partially cover the ZnO surface as 2D and 3D islands adsorb formic acid and decompose it into formate and hydrogen much like the Cu(110) surface. The surface formate from the Cu film decomposes at 470-500 K to give primarily CO 2 and H 2, also much like Cu(110), although atom-thin Cu islands also give ˜ 40% CO. Annealed Cu films give formate decomposition peaks at 25-50 K lower in temperature, attributed to thickening and ordering of the Cu islands to form Cu(111)-like sites. The acid D(H) atom from the formic acid is partially lost by hydrogen spillover from the Cu islands into the ZnO substrate, especially for thin Cu films. This effect partially desorbs and is enhanced upon preannealing the Cu layers, due to increased H diffusion rates across the annealed Cu islands, and/or the decrease in island size. Bulk D(H) is slowly removed as D 2, HD and H 2 above 400 K in diffusion-limited desorption, catalyzed by Cu.

  18. The effect of Cu/Zn molar ratio on CO{sub 2} hydrogenation over Cu/ZnO/ZrO{sub 2}/Al{sub 2}O{sub 3} catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Shaharun, Salina, E-mail: salinashaharun@gmail.com, E-mail: maizats@petronas.com.my; Shaharun, Maizatul S., E-mail: salinashaharun@gmail.com, E-mail: maizats@petronas.com.my; Taha, Mohd F., E-mail: faisalt@petronas.com.my [Department of Fundamental and Applied Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia); Mohamad, Dasmawati, E-mail: dasmawati@kck.usm.my [School of Dental Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan (Malaysia)

    2014-10-24

    Catalytic hydrogenation of carbon dioxide (CO{sub 2}) to methanol is an attractive way to recycle and utilize CO{sub 2}. A series of Cu/ZnO/Al{sub 2}O{sub 3}/ZrO{sub 2} catalysts (CZAZ) containing different molar ratios of Cu/Zn were prepared by the co-precipitation method and investigated in a stirred slurry autoclave system. The catalysts were characterized by temperature-programmed reduction (TPR), field emission scanning electron microscopy-energy dispersive analysis (FESEM-EDX), X-ray diffraction (XRD) and N{sub 2} adsorption-desorption. Higher surface area, SA{sub BET} values (42.6–59.9 m{sup 2}/g) are recorded at low (1) and high (5) Cu/Zn ratios with the minimum value of 35.71 m{sup 2}/g found for a Cu/Zn of 3. The reducibility of the metal oxides formed after calcination of catalyst samples was also affected due to change in metal-support interaction. At a low reaction temperature of 443 K, total gas pressure of 3.0 MPa and 0.1 g/mL of the CZAZ catalyst, the selectivity to methanol decreased as the Cu/Zn molar ratio increased, and the maximum selectivity of 67.73 was achieved at Cu/Zn molar ratio of 1. With a reaction time of 3h, the best performing catalyst was CZAZ75 with Cu/Zn molar ratio of 5 giving methanol yield of 79.30%.

  19. Development of [{sup 62}Zn/{sup 62}Cu]-DOTA-rituximab as a possible novel in vivo PET generator for anti-CD20 antigen imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gholipour, Nazila [Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of). Dept. of Radiopharmacy; Jalilian, Amir R.; Fazaeli, Yousef; Moradkhani, Sedigheh; Bolourinovin, Fateme [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Sabzevari, Omid [Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of). Dept. of Toxicology and Pharmacology; Khalaj, Ali [Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of). Dept. of Medical Chemistry

    2014-07-01

    In this study, zinc-62 was prepared at radiopharmaceutical grade (for {sup 62}Zn/{sup 62}Cu generator production) using {sup nat}Cu(p, xn) reaction with the production yield of 5.9 mCi/μAh at 30 MeV proton energy (radiochemical separation yield >95%, radionuclidic purity >99% and radiochemical purity >99%). In the next step, rituximab was successively labeled with [{sup 62}Zn]-ZnCl{sub 2} after conjugation with p-SCN-Bz-DOTA followed by molecular filtration and determination of the average number of DOTA conjugated per mAb (6:1) by spectrophotometric method. Radiochemical purity (>97%, measured by ITLC and HPLC), integrity of protein after radiolabeling (gel electrophoresis) and stability of [{sup 62}Zn]-DOTA-rituximab (in final formulation, and human serum) were determined 1-8 h as well as biodistribution studies in wild-type rats followed by coincidence imaging for 6 h. However, the accumulation of the radiolabeled antibody was not consistent with the former reported rituximab conjugates. [{sup 62}Zn]-labeled monoclonal antibodies and fragments can be prepared as potential in vivo PET generators for molecular imaging however, the search for application of stable zinc complexes must be continued.

  20. The evaluation of Cu, Zn, Mn, and Se concentrations in the hair of South American camelids

    Directory of Open Access Journals (Sweden)

    Milada Holasová

    2017-01-01

    Full Text Available The aim of this study was to monitor the content of trace elements in the hair of South American camelids and to evaluate the effect of coat colour, species, age, and sex on their concentration in the hair. The samples were collected from 77 animals – 23 llamas (Llama guanicoe f. gllama and 54 alpacas (Llama guanicoe f. pacos during a spring health check. The concentrations of copper (Cu, zinc (Zn, and manganese (Mn were determined by Flame Atomic Absorption Spectrometry and selenium (Se by Hydride Generation Atomic Absorption Spectrometry. We found the following concentrations (mean ± standard deviation; mg/kg dry matter in the llama hair: Cu 9.70 ± 4.69; Zn 145.20 ± 21.07; Mn 12.49 ± 10.14; Se 0.25 ± 0.14. In alpaca hair we found the following concentrations: Cu 10.22 ± 2.90; Zn 129.81 ± 19.01; Mn 12.67 ± 13.85; Se 0.48 ± 0.24. We found a significant difference between llamas and alpacas in Zn and Se concentrations in the hair. From all the evaluated factors we found that coat colour had the highest effect on Mn and Se concentration. Dark haired animals had significantly higher concentrations of these trace elements than other coloured groups. The evaluation of the concentration of trace elements in the hair of llamas has a potential to be used for the evaluation of long-term status of trace elements in the body; however, it is necessary to continue with experimental work in this area. Our findings can serve as a pilot study for further works in this field.

  1. Graphene/CuS/ZnO hybrid nanocomposites for high performance photocatalytic applications

    International Nuclear Information System (INIS)

    Varghese, Jini; Varghese, K.T.

    2015-01-01

    We herein report a novel, high performance ternary nanocomposite composed of Graphene doped with nano Copper Sulphide and Zinc Oxide nanotubes (GCZ) for photodegradation of organic pollutants. Investigations were made to estimate and compare the Methyl Orange dye (MO) degradation using GCZ, synthesized pristine Graphene (Gr) and Graphene–ZnO hybrid nanocomposite (GZ) under UV light irradiations. The synthesis of nanocomposites involves the simple ultra-sonication and mixing methods. The nanocomposites were characterized using transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Raman spectroscopy, UV–vis absorption spectroscopy and Brunauer–Emmett–Teller (BET) surface area method. The as synthesized GCZ shows better surface area, porosity and band gap energy than as synthesized Gr and GZ. The photocatalytic degradation of methyl orange dye follows as Gr  > GZ due to the stronger adsorbability, large number of photo induced electrons and highest inhibition of charge carrier's recombination of GCZ. The kinetic investigation demonstrates that dye degradation exhibit the pseudo first order kinetic model with rate constant 0.1322, 0.049 and0.0109 min"−"1 corresponding to GCZ, GZ and Gr. The mechanism of dye degradation in presence of photocatalyst is also discussed. This study confirms that GCZ is a more promising material for high performance catalytic applications especially in the dye waste water purification. - Highlights: • Graphene–CuS–ZnO hybrid composites show better surface area, porosity and adsorbability. • CuS–ZnO hybrid nanostructure highly enhanced the photocatalytic activity of Graphene. • Graphene–CuS–ZnO hybrid composites show superior photocatalytic efficiency, rate constant and quantum yield.

  2. Graphene/CuS/ZnO hybrid nanocomposites for high performance photocatalytic applications

    Energy Technology Data Exchange (ETDEWEB)

    Varghese, Jini, E-mail: jini.nano@gmail.com; Varghese, K.T., E-mail: ktvscs@gmail.com

    2015-11-01

    We herein report a novel, high performance ternary nanocomposite composed of Graphene doped with nano Copper Sulphide and Zinc Oxide nanotubes (GCZ) for photodegradation of organic pollutants. Investigations were made to estimate and compare the Methyl Orange dye (MO) degradation using GCZ, synthesized pristine Graphene (Gr) and Graphene–ZnO hybrid nanocomposite (GZ) under UV light irradiations. The synthesis of nanocomposites involves the simple ultra-sonication and mixing methods. The nanocomposites were characterized using transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Raman spectroscopy, UV–vis absorption spectroscopy and Brunauer–Emmett–Teller (BET) surface area method. The as synthesized GCZ shows better surface area, porosity and band gap energy than as synthesized Gr and GZ. The photocatalytic degradation of methyl orange dye follows as Gr <<< GCZ >> GZ due to the stronger adsorbability, large number of photo induced electrons and highest inhibition of charge carrier's recombination of GCZ. The kinetic investigation demonstrates that dye degradation exhibit the pseudo first order kinetic model with rate constant 0.1322, 0.049 and0.0109 min{sup −1} corresponding to GCZ, GZ and Gr. The mechanism of dye degradation in presence of photocatalyst is also discussed. This study confirms that GCZ is a more promising material for high performance catalytic applications especially in the dye waste water purification. - Highlights: • Graphene–CuS–ZnO hybrid composites show better surface area, porosity and adsorbability. • CuS–ZnO hybrid nanostructure highly enhanced the photocatalytic activity of Graphene. • Graphene–CuS–ZnO hybrid composites show superior photocatalytic efficiency, rate constant and quantum yield.

  3. Effect of mineral-enriched diet and medicinal herbs on Fe, Mn, Zn, and Cu uptake in chicken

    Directory of Open Access Journals (Sweden)

    Stef Ducu

    2012-03-01

    Full Text Available Abstract Background The goal of our study was to evaluate the effects of different medicinal herbs rich in polyphenol (Lemon balm, Sage, St. John's wort and Small-flowered Willowherb used as dietary supplements on bioaccumulation of some essential metals (Fe, Mn, Zn and Cu in different chicken meats (liver, legs and breast. Results In different type of chicken meats (liver, legs and breast from chickens fed with diets enriched in minerals and medicinal herbs, beneficial metals (Fe, Mn, Zn and Cu were analysed by flame atomic absorption spectrometry. Fe is the predominant metal in liver and Zn is the predominant metal in legs and breast chicken meats. The addition of metal salts in the feed influences the accumulations of all metals in the liver, legs and breast chicken meat with specific difference to the type of metal and meat. The greatest influences were observed in legs meat for Fe and Mn. Under the influence of polyphenol-rich medicinal herbs, accumulation of metals in the liver, legs and breast chicken meat presents specific differences for each medicinal herb, to the control group that received a diet supplemented with metal salts only. Great influence on all metal accumulation factors was observed in diet enriched with sage, which had significantly positive effect for all type of chicken meats. Conclusions Under the influence of medicinal herbs rich in different type of polyphenol, accumulation of metals in the liver, legs and breast chicken meat presents significant differences from the group that received a diet supplemented only with metal salts. Each medicinal herb from diet had a specific influence on the accumulation of metals and generally moderate or poor correlations were observed between total phenols and accumulation of metals. This may be due to antagonism between metal ions and presence of other chelating agents (amino acids and protein from feeding diets which can act as competitor for complexation of metals and influence

  4. Synthesis, Magnetization, and Electrical Transport Properties of Mn3Zn0.9Cu0.1N

    Directory of Open Access Journals (Sweden)

    Y. Yin

    2013-01-01

    Full Text Available We synthesized Mn3Zn0.9Cu0.1N by solid state reaction, and magnetic as well as electrical transport properties were investigated. It is found that Mn3Zn0.9Cu0.1N exhibits a first-order antiferromagnetism (AFM to paramagnetic (PM transition with the Néel temperature TN ~163 K, and substitution of Cu for Zn would favor ferromagnetism (FM state and weaken AFM ground state, leading to a convex curvature character of M(T curve. With high external fields 10 kOe–50 kOe, magnetic transition remains a robust AFM-PM feature while FM phase is completely suppressed. Thermal hysteresis of M(T under 500 Oe is also suppressed when the magnetic field exceeds 10 kOe. Mn3Zn0.9Cu0.1N exhibits a good metallic behavior except for a slope change around TN, which is closely related to AFM-PM magnetic transition. Compared with the first differential of resistivity with respect to temperature for (dρ/dTMn3ZnN in transition temperature range, the absolute value of (dρ/dTMn3Zn0.9Cu0.1N is much lower which is close to zero.

  5. Effect Of Compaction Pressure And Sintering Temperature On The Liquid Phase Sintering Behavior Of Al-Cu-Zn Alloy

    Directory of Open Access Journals (Sweden)

    Lee S.H.

    2015-06-01

    Full Text Available The liquid phase sintering characteristics of Al-Cu-Zn alloy were investigated with respect to various powder metallurgy processing conditions. Powders of each alloying elements were blended to form Al-6Cu-5Zn composition and compacted with pressures of 200, 400, and 600 MPa. The sintering process was performed at various temperatures of 410, 560, and 615°C in N2 gas atmosphere. Density and micro-Vickers hardness measurements were conducted at different processing stages, and transverse rupture strength of sintered materials was examined for each condition, respectively. The microstructure was characterized using optical microscope and scanning electron microscopy. The effect of Zn addition on the liquid phase sintering behavior during P/M process of the Al-Cu-Zn alloy was also discussed in detail.

  6. Nuclease-like activity of some Cu(II) complexes

    International Nuclear Information System (INIS)

    Durackova, Z.; Fenikova, L.; Svorenova, L.; Labudova, O.; Kollarova, M.; Labuda, J.

    1995-01-01

    The nuclease reaction of a copper complex with the macrocyclic Schiff base ligand tetrabenzo[b,f,j,n][a,3,9,13]tetraaza cyclohexadecine (TAAB) at the cleavage of DNA in aerobic conditions and the presence of ascorbic acid has been investigated and compared with that of the copper phenanthroline complex. The AT specifity of the Cu(TAAB) 2+ for both single-stranded and double-stranded DNA templates was observed. (authors), 4 figs., 6 refs

  7. Composition-dependent photoluminescence properties of CuInS_2/ZnS core/shell quantum dots

    International Nuclear Information System (INIS)

    Hua, Jie; Du, Yuwei; Wei, Qi; Yuan, Xi; Wang, Jin; Zhao, Jialong; Li, Haibo

    2016-01-01

    CuInS_2/ZnS (CIS/ZnS) core/shell quantum dots (QDs) with various Cu/In ratios were synthesized using the hot-injection method, and their photoluminescence (PL) properties were investigated by measuring steady-state and time-resolved PL spectroscopy. The emission peak of the CIS/ZnS QDs were tuned from 680 to 580 nm by decreasing the Cu/In precursor ratio from 1/1 to 1/9. As the Cu/In ratio decreases, the PL lifetimes and PL quantum yields (QYs) of CIS/ZnS core/shell QDs increased firstly and then decreased. Two dominant radiative recombination processes were postulated to analyze composition-dependent PL properties, including the recombination from a quantized conduction band to deep defects state and donor-acceptor pair (DAP) recombination. The decrease of PL efficiency resulted from high density defects and traps, which formed at the interface between CIS core and ZnS shell due to the large off-stoichiometry composition. The PL intensity and peak energy for CIS/ZnS core/shell QDs as a function of temperature were also provided. The thermal quenching further confirmed that the PL emission of CIS/ZnS QDs did not come from the recombination of excitons but from the recombination of many kinds of intrinsic defects inside the QDs as emission centers.

  8. Cu2O-tipped ZnO nanorods with enhanced photoelectrochemical performance for CO2 photoreduction

    Science.gov (United States)

    Iqbal, Muzaffar; Wang, Yanjie; Hu, Haifeng; He, Meng; Hassan Shah, Aamir; Lin, Lin; Li, Pan; Shao, Kunjuan; Reda Woldu, Abebe; He, Tao

    2018-06-01

    The design of Cu2O-tipped ZnO nanorods is proposed here aiming at enhanced photoelectrochemical properties. The tip-selective deposition of Cu2O is confirmed by scanning transmission electron microscopy (STEM). The photoinduced charge behavior like charge generation, separation and transport has been thoroughly studied by UV-vis absorption analysis and different photoelectrochemical characterizations, including transient photocurrent, incident photon-to-current efficiency (IPCE), electrochemical impedance spectroscopy (EIS), intensity-modulated photocurrent spectroscopy (IMPS), and Mott-Schottky measurements. The photoelectrochemical characterizations clearly indicate that ZnO/Cu2O structures exhibit much higher performance than pristine ZnO, due to the formation of p-n junction, as well as the tip selective growth of Cu2O on ZnO. Photocatalytic CO2 reduction in aqueous solution under UV-visible light illumination shows that CO is the main product, and with the increase of the Cu2O content in the heterostructure, the CO yield increases. This work shows that Cu2O-tipped ZnO nanorods possess improved behavior of charge generation, separation and transport, which may work as a potential candidate for photocatalytic CO2 reduction.

  9. Structural and optical properties of Cu-doped ZnS nanoparticles formed in chitosan/sodium alginate multilayer films.

    Science.gov (United States)

    Wang, Liping; Sun, Yujie; Xie, Xiaodong

    2014-05-01

    Chitosan/alginate multilayers were fabricated using a spin-coating method, and ZnS:Cu nanoparticles were generated within the network of two natural polysaccharides, chitosan and sodium alginate. The synthesized nanoparticles were characterized using an X-ray diffractometer (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and atomic force microscopy (AFM). The results showed that cubic zinc blende-structured ZnS:Cu nanoparticles with an average crystal size of ~ 3 nm were uniformly distributed. UV-vis spectra indicate a large quantum size effect and the absorption edge for the ZnS:Cu nanoparticles slightly shifted to longer wavelengths with increasing Cu ion concentrations. The photoluminescence of the Cu-doped ZnS nanoparticles reached a maximum at a 1% doping level. The ZnS:Cu nanoparticles form and are distributed uniformly in the composite multilayer films with a surface average height of 25 nm. Copyright © 2013 John Wiley & Sons, Ltd.

  10. S, Zn, Cr, Cu and Fe changes during fluvial sediments oxidation Transformaciones del S, Zn, Cr, Cu y Fe en sedimentos fluviales durante el proceso de secado

    Directory of Open Access Journals (Sweden)

    María Pía Di Nanno

    2009-12-01

    Full Text Available Acidification of dredged sediments which have been disposed on land is highly dependent on redox shifts. The aim of the present work was to assess changes in sulphur, metal speciation (Zn, Fe, Cr y Cu and acidity caused by a polluted sediment oxidation event. Sediments were dessicated under controlled conditions and sulphide compounds (acid volatile sulphides-AVS- and sulphate, pH and neutralization potential were measured through time during 36 days. Zinc, Cu, Cr and Fe speciation (BCR metal sequential extraction procedure were measured at the beginning of the experiment and at day 22. An acid-base equilibrium method based on the BCR procedure was employed to assess the sediment acidification risk. Some of the re-suspension experiments were inoculated with an Acidithiobacillus ferrooxidans strain to assess biological catalysis on sulphide oxidation. Acid-base equilibrium results indicated the sediment sample had a significant acidification potential. Oxidation increased sulphate levels (56 to 2300 mg S kg-¹ in the desiccation experiment with a temporal evolution adjusted by a logistic model, and a 2100 to 3000 mg SO4 -² L-¹ increase for the resuspension experiments. Sulphide oxidation rates varied between 0 to 3.1.10-9 mg O2 kg-¹ s-¹ for the drying sediment. Zinc changes could be explained partially by ZnS conversion to ZnSO4 during oxidation. Iron reduction could be attributed to an increase in Fe oxides crystallinity. Acid-base equilibrium for the sample indicated it was a potentially acid-generating material. Zinc increased its bioavailability during drying and was the only metal that appeared in significant amounts in solution during re-suspension. Land-filling with dredged sediments could present increased metals bioavailability problems despite having an important and effective neutralization potential.La evaluación de los riesgos de acidificación por deposición de sedimentos dragados en superficie es muy dependiente de los

  11. Free radical scavenging activity and neuroprotective potentials of D138, one Cu(II)/Zn(II) Schiff-base complex derived from N,N'-bis(2-hydroxynaphthylmethylidene)-1,3-propanediamine.

    Science.gov (United States)

    Wang, Che; Cai, Zheng-Xu; You, Zhong-Lu; Guo, Hui-Shu; Shang, De-Jing; Wang, Xiao-Ling; Zhang, Liang; Ma, Li-Jie; Tan, Jun; Le, Wei-Dong; Li, Song

    2014-09-01

    There is increasing evidence that free radicals play an important role in neuronal damages induced by diabetes mellitus or cerebral ischemia insults. Antioxidants with free radical scavenging activities have been shown to be beneficial and neuroprotective for these pathological conditions. Here, we report free radical scavenging activity and neuroprotective potential of D138, one copper(II)/zinc(II) Schiff-base complex derived from N,N'-2(2-hydroxynaphthylmethylidene)-1,3-propanediamine. The data from three in vitro assays, 2,2-diphenyl-1-picrylhydrazyl assay, nitro blue tetrazolium assay and hydroxyl radical scavenging assay, indicated that D138 presented a potent free radical scavenging activity. The neuroprotective and antioxidative effects of D138 were further evaluated in vivo using bilateral common carotid artery occlusion (BCCAO) mouse model and streptozotocin (STZ) diabetic mouse model. Our results indicated that treatment of D138 significantly ameliorated the hippocampal neuronal damage and the oxidative stress levels in these animal models. Moreover, D138 also reversed the behavioral deficiencies induced by BCCAO or STZ, as assessed by Y-maze test and fear conditioning test. In conclusion, all these findings support that D138 exerts free radical scavenging and neuroprotective activities and has the potentials to be a potent therapeutic candidate for brain oxidative damage induced by cerebral ischemia or diabetes mellitus.

  12. In Situ Generated Colloid Transport of Cu and Zn in Reclaimed Mine Soil Profiles Associated with Bio solids Application

    International Nuclear Information System (INIS)

    Miller, J.O.; Karathanasis, A.D.; Matocha, C.J.

    2011-01-01

    Areas reclaimed for agricultural uses following coal mining often receive bio solids applications to increase organic matter and fertility. Transport of heavy metals within these soils may be enhanced by the additional presence of bio solids colloids. Intact monoliths from reclaimed and undisturbed soils in Virginia and Kentucky were leached to observe Cu and Zn mobility with and without bio solids application. Transport of Cu and Zn was observed in both solution and colloid associated phases in reclaimed and undisturbed forest soils, where the presence of unweathered spoil material and bio solids amendments contributed to higher metal release in solution fractions. Up to 81% of mobile Cu was associated with the colloid fraction, particularly when gabbiest was present, while only up to 18% of mobile Zn was associated with the colloid fraction. The colloid bound Cu was exchangeable by ammonium acetate, suggesting that it will release into groundwater resources.

  13. In Situ Generated Colloid Transport of Cu and Zn in Reclaimed Mine Soil Profiles Associated with Bio solids Application

    International Nuclear Information System (INIS)

    Miller, J.O.; Karathanasis, A.D.; Matocha, C.J.

    2011-01-01

    Areas reclaimed for agricultural uses following coal mining often receive bio solids applications to increase organic matter and fertility. Transport of heavy metals within these soils may be enhanced by the additional presence of bio solids colloids. Intact monoliths from reclaimed and undisturbed soils in Virginia and Kentucky were leached to observe Cu and Zn mobility with and without bio solids application. Transport of Cu and Zn was observed in both solution and colloid associated phases in reclaimed and undisturbed forest soils, where the presence of unweathered spoil material and bio solids amendments contributed to higher metal release in solution fractions. Up to 81% of mobile Cu was associated with the colloid fraction, particularly when gibbsite was present, while only up to 18% of mobile Zn was associated with the colloid fraction. The colloid bound Cu was exchangeable by ammonium acetate, suggesting that it will release into groundwater resources.

  14. Formation of a ZnS/Zn(S,O) bilayer buffer on CuInS2 thin film solar cell absorbers by chemical bath deposition

    Science.gov (United States)

    Bär, M.; Ennaoui, A.; Klaer, J.; Kropp, T.; Sáez-Araoz, R.; Allsop, N.; Lauermann, I.; Schock, H.-W.; Lux-Steiner, M. C.

    2006-06-01

    The application of Zn compounds as buffer layers was recently extended to wide-gap CuInS2 (CIS) based thin film solar cells. Using an alternative chemical deposition route for the buffer preparation aiming at the deposition of a single-layer, nominal ZnS buffer without the need for any toxic reactants such as hydrazine has helped us to achieve a similar efficiency as respective CdS-buffered reference devices. In order to shed light on the differences of other Zn-compound buffers deposited in conventional chemical baths [chemical bath deposition (CBD)] compared to the buffer layers deposited by this alternative CBD process, the composition of the deposited buffers was investigated by x-ray excited Auger electron and x-ray photoelectron spectroscopy to potentially clarify their superiority in terms of device performance. We have found that in the early stages of this alternative CBD process a thin ZnS layer is formed on the CIS, whereas in the second half of the CBD the growth rate is greatly increased and Zn(S,O) with a ZnS/(ZnS+ZnO) ratio of ~80% is deposited. Thus, a ZnS/Zn(S,O) bilayer buffer is deposited on the CIS thin film solar cell absorbers by the alternative chemical deposition route used in this investigation. No major changes of these findings after a postannealing of the buffer/CIS sample series and recharacterization could be identified.

  15. Jahn-Teller and Non-Jahn-Teller Systems Involving CuF64- Units: Role of the Internal Electric Field in Ba2ZnF6:Cu2+ and Other Insulating Systems

    DEFF Research Database (Denmark)

    Aramburu, J. A.; Garcia-Fernandez, P.; García Lastra, Juan Maria

    2017-01-01

    The applicability of the Jahn-Teller (JT) framework to 6-fold coordinated d9 ions whose local symmetry is not strictly octahedral is explored by means of first principle calculations. Our results contradict much of the existing literature where these systems are analyzed within the quasi-JT regime...... transitions for CuF64- units formed in Cu2+-doped the tetragonal Ba2ZnF6 host lattice. While the experimental d-d transitions cannot be reproduced through the isolated CuF64- unit at the equilibrium geometry, a reasonable agreement is reached adding in the calculation the internal electric field, ER...... state with the hole in the a1g(∼ 3z2-r2) level while it is always placed in the b1g(∼ x2-y2) level for MX6 complexes (M = Cu2+, Ag2+, NiΤ; X = F--, Cl-) in cubic lattices displaying a static JT effect. While the experimental results of CuF64- in Ba2ZnF6 cannot be understood within the JT framework...

  16. Thermoelectric properties of chalcogenide based Cu2+xZnSn1−xSe4

    Directory of Open Access Journals (Sweden)

    Ch. Raju

    2013-03-01

    Full Text Available Quaternary chalcogenide compounds Cu2+xZnSn1−xSe4 (0 ≤ x ≤ 0.15 were prepared by solid state synthesis. Rietveld powder X-ray diffraction (XRD refinements combined with Electron Probe Micro Analyses (EPMA, WDS-Wavelength Dispersive Spectroscopy and Raman spectra of all samples confirmed the stannite structure (Cu2FeSnS4-type as the main phase. In addition to the main phase, small amounts of secondary phases like ZnSe, CuSe and SnSe were observed. Transport properties of all samples were measured as a function of temperature in the range from 300 K to 720 K. The electrical resistivity of all samples decreases with an increase in Cu content except for Cu2.1ZnSn0.9Se4, most likely due to a higher content of the ZnSe. All samples showed positive Seebeck coefficients indicating that holes are the majority charge carriers. The thermal conductivity of doped samples was high compared to Cu2ZnSnSe4 and this may be due to the larger electronic contribution and the presence of the ZnSe phase in the doped samples. The maximum zT = 0.3 at 720 K occurs for Cu2.05ZnSn0.95Se4 for which a high-pressure torsion treatment resulted in an enhancement of zT by 30% at 625 K.

  17. Effect of Fertilizers and Irrigation on Distribution of Mobile Forms of Mn, Zn and Cu in Typical Chernozems of the Republic of Moldova

    Directory of Open Access Journals (Sweden)

    Leah T. Gh.

    2013-04-01

    Full Text Available The paper presents the study results of mobile forms of Mn, Zn and Cu in irrigated fertilized and unfertilized chernozems typical. Irrigation affects the content and distribution of mobile forms of trace elements, increasing their removal beyond the 150 cm of soil layer. The fertilization increase the migration of Cu until 130 cm, fixed Mn and Zn in 0-60 cm of the irrigated soils. During irrigation constitutes a danger of soil contamination with Mn, Cu and Zn.

  18. Novel chemical route for deposition of Cu{sub 2}ZnSnS{sub 4} photovoltaic absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Gordillo, Gerardo; Becerra, Raul A.; Calderón, Clara L., E-mail: ggordillog@unal.edu.co [Universidad Nacional de Colombia, Bogota (Colombia)

    2018-05-01

    This work reports results of a study carried out to optimize the preparation conditions of Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films grown by sequential deposition of Cu{sub 2}SnS{sub 3} (CTS) and ZnS layers, where the Cu{sub 2}SnS{sub 3} compound was grown using a novel procedure consisting of simultaneous precipitation of Cu{sub 2}S and SnS{sub 2} performed by diffusion membrane assisted chemical bath deposition (CBD) technique. The precipitation across the diffusion membranes allows achieving moderate control of release of metal ions into the work solution favoring the heterogeneous growth mainly through an ion-ion mechanism. Through a parameters study, conditions were found to grow Cu{sub 2}SnS{sub 3} thin films which were used as precursors for the formation of Cu{sub 2}ZnSnS{sub 4} films. The formation of CZTS thin films grown in the Cu{sub 2}ZnSnS{sub 4} phase was verified through measurements of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Solar cells with efficiencies of 4.9% were obtained using CZTS films prepared by membrane assisted CBD technique as absorber layer. (author)

  19. Spectral features and antibacterial properties of Cu-doped ZnO nanoparticles prepared by sol-gel method

    International Nuclear Information System (INIS)

    Samavati, Alireza; Nur, Hadi; Othaman, Z; Ismail, A F; Mustafa, M K

    2016-01-01

    Zn 1−x Cu x O (x = 0.00, 0.01, 0.03, and 0.05) nanoparticles are synthesized via the sol-gel technique using gelatin and nitrate precursors. The impact of copper concentration on the structural, optical, and antibacterial properties of these nanoparticles is demonstrated. Powder x-ray diffraction investigations have illustrated the organized Cu doping into ZnO nanoparticles up to Cu concentration of 5% ( x = 0.05). However, the peak corresponding to CuO for x = 0.01 is not distinguishable. The images of field emission scanning electron microscopy demonstrate the existence of a nearly spherical shape with a size in the range of 30–52 nm. Doping Cu creates the Cu–O–Zn on the surface and results in a decrease in the crystallite size. Photoluminescence and absorption spectra display that doping Cu causes an increment in the energy band gap. The antibacterial activities of the nanoparticles are examined against Escherichia coli (Gram negative bacteria) cultures using optical density at 600 nm and a comparison of the size of inhibition zone diameter. It is found that both pure and doped ZnO nanoparticles indicate appropriate antibacterial activity which rises with Cu doping. (paper)

  20. Formation of polar surfaces in microstructured ZnO by doping with Cu and applications in photocatalysis using visible light

    International Nuclear Information System (INIS)

    Pawar, Rajendra C.; Choi, Da-Hyun; Lee, Jai-Sung; Lee, Caroline S.

    2015-01-01

    We report the synthesis of copper-doped zinc oxide microstructures with a large amount of polar surfaces using a single-step facile chemical method by collecting powders of zinc oxide (ZnO) microstructures. It was found that rod-like morphology of ZnO transformed into disk and sphere-like structure with nanosheets. Hollow disk-like structures were formed due to the surface etching properties of Cl − ions in the copper chloride precursor. The photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) dyes was measured under irradiation with visible light using the structures as catalysts. The Cu-doped ZnO exhibited better photodegradation properties than did undoped ZnO. The enhanced performance is attributed to the existence of (001) polar surfaces, oxygen vacancies, and increased optical absorbance at visible wavelengths, which is consistent with the field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), room temperature photoluminescence (PL), and optical absorbance measurements. These favorable photocatalytic properties of the doped microstructures demonstrate their potential for use in wastewater treatment. - Graphical abstract: Graphical abstract shows the electron transfer mechanism under visible light for Cu-doped ZnO microstructures and the photocatalytic degradation of dye. - Highlights: • Cu induced microstructures of ZnO with polar surfaces. • Methylene blue degradation under visible light irradiation. • Room temperature ferromagnetism due to oxygen vacancies in ZnO. • 7% Cu–ZnO has highest photocatalytic activity

  1. Red light emission from ZnO:Eu"3"+|CuSCN hetero-junction under cathodic polarization

    International Nuclear Information System (INIS)

    Sirimanne, P.M.; Minoura, H.

    2015-01-01

    Eu"3"+ ions were bonded to ZnO ceramic via organic ligand. Surface bonded Eu"3"+ ions were exhibited specific luminescence bands due to electron transitions between f–f intra-configurationally transitions. Further enhancement of luminescence bands was observed by attaching selected oligomers to Eu"3"+ ions. A hetero-junction was prepared by depositing copper-thiocyanate on Eu"3"+ ions bonded ZnO ceramic. Red light emission was observed from surface bonded Eu"3"+ ions in ZnO:Eu"3"+|CuSCN hetero-junction under reverse bias. - Highlights: • Europium doped ZnO ceramic exhibits photo-luminescence. • Semiconductor hetro-junction was prepared. • ZnO:Eu"3"+|CuSCN hetero-junction emits red light under reverse bias.

  2. Passive optical limiting studies of nanostructured Cu doped ZnO-PVA composite thin films

    Science.gov (United States)

    Tamgadge, Y. S.; Sunatkari, A. L.; Talwatkar, S. S.; Pahurkar, V. G.; Muley, G. G.

    2016-01-01

    We prepared undoped and Cu doped ZnO semiconducting nanoparticles (NPs) by chemical co-precipitation method and obtained Cu doped ZnO-polyvinyl alcohol (PVA) nanocomposite thin films by spin coating to investigate third order nonlinear optical and optical limiting properties under cw laser excitation. Powder samples of NPs were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy, transmission electron microscopy, ultraviolet-visible (UV-vis) and Fourier transform infrared spectroscopy. XRD pattern and FE-SEM micrograph revealed the presence of hexagonal wurtzite phase ZnO NPs having uniform morphology with average particle size of 20 nm. The presence of excitons and absorption peaks in the range 343-360 nm, revealed by UV-vis study, were attributed to excitons in n = 1 quantum state. Third order NLO properties of all composite thin films were investigated by He-Ne continuous wave (cw) laser of wavelength 632.8 nm using Z-scan technique. Thermally stimulated enhanced values of nonlinear refraction and absorption coefficients were obtained which may be attributed to self-defocusing effect, reverse saturable absorption, weak free carrier absorption and surface states properties originated from thermo optic effect. Optical limiting properties have been studied using cw diode laser of wavelength 808 nm and results are presented.

  3. Radiation hardening at 77 K in Zn and Cu single crystals at low doses

    International Nuclear Information System (INIS)

    Gonzalez, H.C.; Bisogni, E.A.

    1980-01-01

    There is controversy about radiation hardening phenomenon and its additivity with other hardening mechanisms. The purpose of this work is to contribute to the understanding of this subject, through measurements made in Zn and Cu single crystals. Post-irradiation measurements of yield stress of Zn, made on different single crystals, show a direct proportionality to the 0.5 power of the dose. It is determined that for a dose greater than 3.7 x 10 16 neutrons cm -2 s -1 there is always cleavage. The maximum critical resolved shear stress measured is about 8.82 MPa. In order to study additivity it is necessary to lower experimental errors. A micro tensile machine is designed to operate in the CNEA facility RA1 in a bath of liquid N 2 . Experimental measurements of yield stress with dose are carried out in-situ on the same single crystals. Experimental results on Cu and Zn show that radiation induced yield stress increases with a 0.5 power law. It must be taken into account that the definition of radiation induced yield stress stands for radiation created obstacles operating alone. The radiation induced yield stress adds algebraically to the athermal component of the initial yield stress but is not exactly additive to the other thermally activated mechanisms. A gradual transition from one to the other type of obstacles is observed. (author)

  4. Spray-coated ligand-free Cu2ZnSnS4 nanoparticle thin films

    DEFF Research Database (Denmark)

    Engberg, Sara Lena Josefin; Murthy, Swathi; Kofod, Guggi

    We have fabricated Cu2ZnSnS4 (CZTS) thin films from spray-coating ligand-free nanoparticle inks. The as-synthesized CZTS nanoparticles were inherently ligand-free [1], which allows the use of polar solvents, such as water and ethanol. Another advantage of these particles is that user- and environ......We have fabricated Cu2ZnSnS4 (CZTS) thin films from spray-coating ligand-free nanoparticle inks. The as-synthesized CZTS nanoparticles were inherently ligand-free [1], which allows the use of polar solvents, such as water and ethanol. Another advantage of these particles is that user......- and environmentally-friendly alkali metal chloride salts can be directly dissolved in controllable amounts. The homogeneous distribution of alkali metals in the ink allows uniform grain growth within the deposited absorber layer as a result of liquid phase assisted sintering. We find that particularly beneficial...... as an unquantifiable amount of ZnS. A Sono-tek spray-coating system is used which utilizes ultrasonic atomization. We investigate the effect of different binders, ink concentration, and spray-coating conditions, i.e. spray power, flow rate from syringe pump, distance between spray nozzle and the substrate, and time...

  5. Effect of Cu addition on the microstructure and mechanical properties of Al–30 wt% Zn alloy

    International Nuclear Information System (INIS)

    Abd El-Rehim, A.F.; Sakr, M.S.; El-Sayed, M.M.; Abd El-Hafez, M.

    2014-01-01

    Highlights: • This paper describes a novel work on the effect of Cu addition on the Al–30 wt% Zn alloy. • The 1 wt% Cu alloy revealed the best hardness of the alloys. • The results indicated two deformation temperature regions (below and above 548 K). - Abstract: The effect of 0.5, 1, 1.5 and 2 wt% Cu addition on the microstructure and mechanical properties of Al–30 wt% Zn alloy has been investigated by stress–strain tests carried out in the temperature range from 508 to 608 K. The work-hardening parameters of the test alloys decreased with increasing the deformation temperature and exhibited discontinuity at 548 K, resulting two deformation temperature regions, the low-temperature region (below 548 K) and high-temperature region (above 548 K). The activation energy of fracture mechanisms has been calculated and found to be 19.6 and 33.2 kJ/mol at the low and high temperature regions respectively. The operating mechanisms of work-hardening of the test alloys were confirmed by the analysis of X-ray diffraction patterns

  6. In situ release rates of Cu and Zn from commercial antifouling paints at different salinities.

    Science.gov (United States)

    Lagerström, Maria; Lindgren, J Fredrik; Holmqvist, Albin; Dahlström, Mia; Ytreberg, Erik

    2018-02-01

    Antifouling paints are environmentally risk assessed based on their biocidal release rates to the water phase. In situ release rates of copper (Cu) and zinc (Zn) were derived for five commercial paints in two recreational marinas with different salinities (5 and 14 PSU) using an X-Ray Fluorescence spectrometer (XRF). Salinity was found to significantly affect the Cu release, with twice the amount of Cu released at the higher salinity, while its influence on the Zn release was paint-specific. Site-specific release rates for water bodies with salinity gradients, e.g. the Baltic Sea, are therefore necessary for more realistic risk assessments of antifouling paints. Furthermore, the in situ release rates were up to 8 times higher than those generated using standardized laboratory or calculation methods. The environmental risk assessment repeated with the field release rates concludes that it is questionable whether the studied products should be allowed on the Swedish market. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Metal (Cu, Cd and Zn) removal and stabilization during multiple soil washing by saponin.

    Science.gov (United States)

    Gusiatin, Zygmunt Mariusz; Klimiuk, Ewa

    2012-01-01

    The influence of multiple saponin washing on copper, cadmium and zinc removal and stability in three types of soils (loamy sand, loam, silty clay) was investigated. Distribution of metals and their mobility measured as the ratio of exchangeable form to the sum of all fractions in soils was differential. After single washing the highest efficiency of metal removal was obtained in loamy sand (82-90%) and loam (67-88%), whereas the lowest in silty clay (39-62%). In loamy sand and loam metals had higher mobility factors (44-61% Cu, 60-76% Cd, and 68-84% Zn) compared to silty clay (9% Cu, 28% Cd and 36% Zn). Triplicate washing led to increase both efficiency of metal removal and percentage content of their stable forms. In consequence, fractional patterns for metals before and after treatment changed visibly as a result of their redistribution. Based on the redistribution index, the most stable metal (mainly in residual and organic fractions) after triplicate washing was Cu in loamy sand and loam. For silty clay contaminated with Cd, effective metal removal and its stabilization required a higher number of washings. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Decay Spectroscopy of 76-79Cu, 79-81Zn, and 83-85Ga

    International Nuclear Information System (INIS)

    Gross, C.J.; Winger, J.A.; Ilyushkin, S.; Rykaczewski, K.P.; Liddick, S.N.; Darby, I.G.; Grzywacz, R.K.; Bingham, C.R.; Shapira, D.; Mazzocchi, C.; Padgett, S.; Rajabali, M.M.; Cartegni, L.; Zganjar, E.F.; Piechaczek, A.; Batchelder, J.C.; Hamilton, J.H.; Goodin, C.T.; Korgul, A.; Krolas, W.

    2009-01-01

    The β-decay properties of neutron-rich fission fragments of Cu, Zn, and Ga isotopes were studied at the Holifield Radioactive Ion Beam Facility. Beams of 75-79 Cu, 79-81 Zn, and 83-85 Ga were formed and delivered to two new end-stations at the facility. The Low-energy Radioactive Ion Beam Spectroscopy Station is a traditional on-line low energy (200 keV) beam line with 4 clover Ge detectors, two half-cylindrical plastic β-detectors, and a moving tape collector. In addition, many of the beams were accelerated to above 2 MeV/u and delivered to a micro-channel plate and transmission ion chamber located just in front of the same detector setup. In both cases, fine adjustment of an isobar separator was used to enhance the isotope of interest. Excited levels in the daughters and β-delayed neutron branching ratios were measured and used to confirm isotope identification. The decays from 79 Cu and 85 Ga were observed for the first time as was the 84 Ge 2 1 + level populated by β and βn decay channels

  9. Synthesis and crystal structure of three new quaternary compounds in the system (Cu-III-Se{sub 2}){sub 1-x}ZnSe{sub x} (III = Al, Ga, In), formed by Zn incorporation in Cu-III-Se{sub 2} chalcopyrite s

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, G. E. [Universidad de Los Andes, Facultad de Ciencias, Departamento de Quimica, Laboratorio de Cristalografia, 5101 Merida (Venezuela, Bolivarian Republic of); Grima G, P.; Quintero, M., E-mail: gerzon@ula.ve [Universidad de Los Andes, Facultad de Ciencias, Departamento de Fisica, Centro de Estudios de Semiconductores, 5101 Merida (Venezuela, Bolivarian Republic of)

    2016-11-01

    The crystal structure of the chalcogenide alloys CuZnAlSe{sub 3}, CuZnCaSe{sub 3} and CuZnInSe{sub 3}, new members of the system I-II-III-VI{sub 3}, were characterized using X-ray powder diffraction data. All materials crystallize in the tetragonal space group P{sub -4} 2{sub c} (N 112) with a CuFeInSe{sub 3}- type structure. (Author)

  10. Spectroscopic characterization of some Cu(II) complexes

    International Nuclear Information System (INIS)

    Singh, Puja; Sharma, S.

    2014-01-01

    3-hydroxy-4-methoxy benzaldehyde semicarbazone (HMBS) is a biologically active compound which has several potential donor sites. This compound has been used for complexation with Cu(II) ions to synthesize complexes of general formula [Cu(HMBS) 2 X 2 ] where X is Cl − , NO 3 − and CH 3 COO − . Cu(II) is a d 9 system for which 2 D term is generated. Under O h symmetry, this term splits into 2 E g and 2 T 2g . the ground term 2 Eg is doubly degenerate and hence suffers strong Jahn-Teller effect and accordingly the further splitting of terms occur to lower the symmetry from perfect O h . Here, the ligand occupies four planar positions while the two axial positions have been varied by using different ions like Cl − , NO 3 − and CH 3 COO − . These variations on the axial positions also add to the distortion in O h symmetry. Under strong distortion, the electronic spectral band splits into multiplets exhibiting tetragonal distortion in complexes. The extent of distortion has been derived by the derivation of the two radial parameters D s and D t from electronic spectral bands. The ESR spectra of complexes reveal the real position of the only unpaired electron of the d 9 system in complexes

  11. Cu{sub 2}ZnSn(S,Se){sub 4} from Cu{sub x}SnS{sub y} nanoparticle precursors on ZnO nanorod arrays

    Energy Technology Data Exchange (ETDEWEB)

    Kavalakkatt, Jaison, E-mail: jai.k@web.de [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Freie Universitaet Berlin, Berlin (Germany); Lin, Xianzhong; Kornhuber, Kai [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Kusch, Patryk [Freie Universitaet Berlin, Berlin (Germany); Ennaoui, Ahmed [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Reich, Stephanie [Freie Universitaet Berlin, Berlin (Germany); Lux-Steiner, Martha Ch. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Freie Universitaet Berlin, Berlin (Germany)

    2013-05-01

    Solar cells with Cu{sub 2}ZnSnS{sub 4} absorber thin films have a potential for high energy conversion efficiencies with earth-abundant and non-toxic elements. In this work the formation of CZTSSe from Cu{sub x}SnS{sub y} nanoparticles (NPs) deposited on ZnO nanorod (NR) arrays as precursors for zinc is investigated. The NPs are prepared using a chemical route and are dispersed in toluene. The ZnO NRs are grown on fluorine doped SnO{sub 2} coated glass substrates by electro deposition method. A series of samples are annealed at different temperatures between 300 °C and 550 °C in selenium containing argon atmosphere. To investigate the products of the reaction between the precursors the series is analyzed by means of X-ray diffraction (XRD) and Raman spectroscopy. The morphology is recorded by scanning electron microscopy (SEM) images of broken cross sections. The XRD measurements and the SEM images show the disappearing of ZnO NRs with increasing annealing temperature. Simultaneously the XRD and Raman measurements show the formation of CZTSSe. The formation of secondary phases and the optimum conditions for the preparation of CZTSSe is discussed. - Highlights: ► Cu{sub x}SnS{sub y} nanoparticles are deposited on ZnO nanorod arrays. ► Samples are annealed at different temperatures (300–550 °C) in Se/Ar-atmosphere. ► Raman spectroscopy, X-ray diffraction and electron microscopy are performed. ► ZnO disappears with increasing annealing temperature. ► With increasing temperature Cu{sub x}SnS{sub y} and ZnO form Cu{sub 2}ZnSn(S,Se){sub 4}.

  12. Growth and characterization of p-Cu2O/n-ZnO nanorod heterojunctions prepared by a two-step potentiostatic method

    International Nuclear Information System (INIS)

    Jeong, Yoon Suk; Kim, Hyunghoon; Lee, Ho Seong

    2013-01-01

    Highlights: •p-Cu 2 O/n-ZnO heterostructures were grown by a two-step potentiostatic method. •The high-quality p-Cu 2 O/n-ZnO nanorod heterojunctions were obtained only at relatively high temperatures of 90 and 100 °C. •p-Cu 2 O/n-ZnO heterojunctions exhibited a well-defined p–n diode characteristic. -- Abstract: p-Cu 2 O/n-ZnO nanorod heterojunctions were fabricated by a two-step process. The process was performed with potentiostatic deposition of n-ZnO nanorods on conductive indium-tin-oxide (ITO) glasses followed by potentiostatic deposition of p-Cu 2 O to form p-Cu 2 O/n-ZnO nanorod heterojunctions. The deposition condition required to form the cuprous oxide layer affected significantly the formation and microstructure of the p-Cu 2 O/n-ZnO nanorod heterojunctions. In particular, the high-quality p-Cu 2 O/n-ZnO nanorod heterojunctions were obtained only at relatively high temperatures of 90 and 100 °C. The p-Cu 2 O/n-ZnO nanorod heterojunctions exhibited a well-defined p–n diode characteristic with an ideality factor of about 4.3

  13. Crystalline nanostructured Cu doped ZnO thin films grown at room temperature by pulsed laser deposition technique and their characterization

    Energy Technology Data Exchange (ETDEWEB)

    Drmosh, Qasem A. [Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Rao, Saleem G.; Yamani, Zain H. [Laser Research Group, Department of Physics, Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Gondal, Mohammed A., E-mail: magondal@kfupm.edu.sa [Laser Research Group, Department of Physics, Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2013-04-01

    We report structural and optical properties of Cu doped ZnO (ZnO:Cu) thin films deposited on glass substrate at room temperature by pulsed laser deposition (PLD) method without pre and post annealing contrary to all previous reports. For preparation of (ZnO:Cu) composites pure Zn and Cu targets in special geometrical arrangements were exposed to 248 nm radiations generated by KrF exciter laser. The laser energy was 200 mJ with 10 Hz frequency and 20 ns pulse width. The effect of Cu concentration on crystal structure, morphology, and optical properties were investigated by XRD, FESEM and photoluminescence spectrometer respectively. A systematic shift in ZnO (0 0 2) peak with Cu concentration observed in XRD spectra demonstrated that Cu ion has been incorporated in ZnO lattice. Uniform film with narrow size range grains were observed in FESEM images. The photoluminescence (PL) spectra measured at room temperature revealed a systematic red shift in ZnO emission peak and decrease in the band gap with the increase in Cu concentration. These results entail that PLD technique can be realized to deposit high quality crystalline ZnO and ZnO:Cu thin films without pre and post heat treatment which is normally practiced worldwide for such structures.

  14. Determination of mobile form contents of Zn, Cd, Pb and Cu in soil extracts by combined stripping voltammetry

    Energy Technology Data Exchange (ETDEWEB)

    Nedeltcheva, T. [Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 8 Kl. Ohridsi Blvd., 1756 Sofia (Bulgaria)]. E-mail: nedel@uctm.edu; Atanassova, M. [Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 8 Kl. Ohridsi Blvd., 1756 Sofia (Bulgaria); Dimitrov, J. [N. Pushkarov Institute of Soil Science and Agroecology, 7 Shosse Bankya St., 1080 Sofia (Bulgaria); Stanislavova, L. [N. Pushkarov Institute of Soil Science and Agroecology, 7 Shosse Bankya St., 1080 Sofia (Bulgaria)

    2005-01-10

    The amount of mobile forms of Zn, Pb, Cd and Cu in extracts obtained by treating soil samples with ammonium nitrate were determined by an appropriate combination of anodic and cathodic stripping voltammetry with hanging mercury drop electrode. Every analysis required three mercury drops: on the first one, zinc was determined; on the second, cadmium and lead; on the third, copper was determined. Zinc, lead and cadmium were determined by conventional differential-pulse anodic stripping voltammetry. For copper determination, adsorptive differential-pulse cathodic stripping voltammetry with amalgamation using chloride ions as a complexing agent was applied. The standard deviation of the results was from 1 to 10% depending on the metal content in the sample. Voltammetric results were in good agreement with the AAS analysis. No microwave digestion of soil extracts was necessary.

  15. Determination of mobile form contents of Zn, Cd, Pb and Cu in soil extracts by combined stripping voltammetry

    International Nuclear Information System (INIS)

    Nedeltcheva, T.; Atanassova, M.; Dimitrov, J.; Stanislavova, L.

    2005-01-01

    The amount of mobile forms of Zn, Pb, Cd and Cu in extracts obtained by treating soil samples with ammonium nitrate were determined by an appropriate combination of anodic and cathodic stripping voltammetry with hanging mercury drop electrode. Every analysis required three mercury drops: on the first one, zinc was determined; on the second, cadmium and lead; on the third, copper was determined. Zinc, lead and cadmium were determined by conventional differential-pulse anodic stripping voltammetry. For copper determination, adsorptive differential-pulse cathodic stripping voltammetry with amalgamation using chloride ions as a complexing agent was applied. The standard deviation of the results was from 1 to 10% depending on the metal content in the sample. Voltammetric results were in good agreement with the AAS analysis. No microwave digestion of soil extracts was necessary

  16. Formation of a ZnS Zn S,O bilayer buffer on CuInS2 thin film solar cell absorbers by chemical bath deposition

    OpenAIRE

    Bär, M.; Ennaoui, A.; Klaer, J.; Kropp, T.; S ez Araoz, R.; Allsop, N.; Lauermann, I.; Schock, H. W.; Lux Steiner, M.C

    2006-01-01

    The application of Zn compounds as buffer layers was recently extended to wide gap CuInS2 CIS based thin film solar cells. Using a new chemical deposition route for the buffer preparation aiming at the deposition of a single layer, nominal ZnS buffer without the need for any toxic reactants such as, e.g. hydrazine, has helped to achieve a similar efficiency as respective CdS buffered reference devices. In order to shed light on the differences of other Zn compound buffers deposited in con...

  17. Optical properties of oxide magnetic ZnO, Zn{sub 0.95}Mn{sub 0.05}O and Cu{sub 2}O nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Sokolov, V.I., E-mail: visokolov@imp.uran.r [Institute of Metal Physics UD RAS, S.Kovalevskaya Str. 18, 620041 Yekaterinburg (Russian Federation); Yermakov, A.Ye.; Uimin, M.A.; Mysik, A.A. [Institute of Metal Physics UD RAS, S.Kovalevskaya Str. 18, 620041 Yekaterinburg (Russian Federation); Pustovarov, V.A. [Ural State Technical University, Mira Street 19, 620002 Yekaterinburg (Russian Federation); Chukichev, M.V. [M.V. Lomonosov Moscow State University, Physics Faculty, 119991 Moscow (Russian Federation); Gruzdev, N.B. [Institute of Metal Physics UD RAS, S.Kovalevskaya Str. 18, 620041 Yekaterinburg (Russian Federation)

    2009-12-15

    ZnO, Zn{sub 0.95}Mn{sub 0.05}O and Cu{sub 2}O nanocrystals are synthesized. Excitonic lines in absorption spectra of these materials are detected. In photoluminescence and photoluminescence excitation spectra of Zn{sub 0.95}Mn{sub 0.05}O the dangling bond hybrid (DBH) state is found. It has splitted out from the top of the valence band due to the hybridization between d-states of the Mn impurity and the p-states of oxygen.

  18. Cu{sub 2}ZnSnS{sub 4} thin films obtained by sulfurization of evaporated Cu{sub 2}SnS{sub 3} and ZnS layers: Influence of the ternary precursor features

    Energy Technology Data Exchange (ETDEWEB)

    Robles, V.; Guillén, C., E-mail: c.guillen@ciemat.es; Trigo, J.F.; Herrero, J.

    2017-04-01

    Highlights: • Kesterite Cu{sub 2}ZnSnS{sub 4} is got by sulfurization of evaporated Cu{sub 2}SnS{sub 3} and ZnS layers. • Smooth films are obtained by decreasing the growth temperature of Cu{sub 2}SnS{sub 3}. • The lattice strain and the electrical conductivity increase with the Cu-content. • The energy gap diminishes as the Cu-content and/or the surface roughness increase. - Abstract: Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films have been grown by sulfurization of Cu{sub 2}SnS{sub 3} (CTS) and ZnS layers evaporated on glass substrates. Four CTS precursor films have been tested, with two different atomic compositions (Cu/Sn = 1.7 and Cu/Sn = 2.1) and substrate temperatures (350 and 450 °C), together with analogous ZnS layers deposited by maintaining the substrate at 200 °C. The sulfurization of the CTS and ZnS stacked layers was performed at 500 °C during 1 h. The evolution of the crystalline structure, morphology, optical and electrical properties from each CTS precursor to the CZTS compound has been studied, especially the influence of the ternary precursor features on the quaternary film characteristics. The kesterite structure has been identified after sulfurization of the various samples, with main (112) orientation and mean crystallite sizes S{sub 112} = 40–56 nm, being higher for the Cu-poor compositions. The CZTS average roughness has varied in a wide interval R{sub a} = 8–66 nm, being directly related to the CTS precursor layer, which becomes rougher for a higher deposition temperature or Cu content. Besides, the band gap energy and the electrical resistivity of the CZTS films have changed in the ranges E{sub g} = 1.54–1.64 eV and ρ = 0.2–40 Ωcm, both decreasing when the Cu content and/or the surface roughness increase.

  19. Evaluation of Sintering Behavior of Premix Al-Zn-Mg-Cu Alloy Powder

    Directory of Open Access Journals (Sweden)

    Haris Rudianto

    2015-01-01

    Full Text Available Sintering of light aluminium alloys powder has been investigated as a way to substitute steels in automotive and aerospace industries. Premix Al-5.5Zn-2.5Mg-0.5Cu composite powder called Alumix 431D was analyzed in this research. Sintering was carried out under ultra high purity nitrogen gas and before reaching sintering temperature, green samples were delubricated at 400°C for 30 min. The powder possesses high sinterability by reaching 96% relative density at 580°C sintering temperature. Formation of liquid phase seems to support achieving high sintering density. Optimum mechanical properties also were obtained under those conditions. T6 heat treatment was done to improve the mechanical properties by formation of precipitation strengthening, and MgZn2 appears to be dominant strengthening precipitate. X-ray diffraction, optical microscopy, and SEM-EDS were used to characterize powder, and sintered and heat treated samples.

  20. Tuning Cu dopant of Zn 0.5 Cd 0.5 S nanocrystals enables high-performance photocatalytic H 2 evolution from water splitting under visible-light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Zongwei; Zhang, Bingkai; Zheng, Jiaxin; Yuan, Sheng; Zhuo, Zengqing; Meng, Xianguang; Chen, Zonghai; Amine, Khalil; Yang, Wanli; Wang, Lin. -Wang; Wang, Wei; Wang, Shufeng; Gong, Qihuang; Li, Jun; Liu, Fu. -Sheng; Pan, Feng

    2016-08-01

    Cu-doping into Zn1-xCdxS can greatly enhance the photocatalytic H2 evolution from water splitting under visible-light irradiation. However, it is still controversial for how the Cu-dopant improves this performance. Here, we report that appropriate Cu-doped Zn0.5Cd0.5S nanocrystals reach 21.4 mmol/h/g of H2 evolution rate without cocatalyst in the visible-light region, which is also 2.8 times as high as that of the undoped counterpart, and the corresponding apparent quantum efficiency is 18.8% at 428 nm. It is firstly confirmed that the Cu2+ changes into Cu+ after being doped by soft X-ray absorption spectroscopy (sXAS). We theoretically propose that the transformation of 2Cu2+ to 2Cu+ results in one adjacent S2- vacancy (VS) in host during the doping process, while the Cu+-dopant and VS attract the photoexcited holes and electrons, respectively. Accordingly, the photocatalytic activity is improved due to the enhanced separation of photoexcited carriers accompanied with the enhanced light absorption resulting from the Cu+-dopant and 2Cu+/VS complex as possible active site for photocatalytic H2 evolution.

  1. Approach to study of Cu, Ni and Zn content in soil for ecotoxicological risk assessment

    Science.gov (United States)

    Boluda, R.; Marimon, L.; Gil, C.; Roca-Pérez, L.

    2009-04-01

    Current Spanish legislation on contaminated soils defines contaminated soil as "that whose characteristics have been negatively altered by the presence of dangerous human-derived chemical components whose concentration is such that it is an unacceptable risk for human health or the environment and has been expressly declared as such by legal ruling". Regarding heavy metals, the Spanish Autonomous Communities will promote measures to obtain generic reference values to declare a soil to be contaminated. In the Valencian Community, these reference values still do not exist. So if the protection of ecosystems is considered a priority to declare a soil to be contaminated and to assess the level of risk, emergency toxicity tests and seed growth in land plants are resorted to, or tests with aquatic organisms or other experiments with leached soils obtained by standard procedures are carried out. We studied the toxic effects of calcareous contaminated soils by Cu, Ni and Zn on marine bacterium Vibrio fisheri (MicrotoxR test assay) (1) and on barley (Hordeum vulgare L.) in plate (germination index) (2) and pot (UNE 77301) (3) experiments for the purpose of establishing the Cu, Ni and Zn concentrations in soil which may lead to toxicity in order to observe, therefore, whether there is any likelihood of these pollutants coming into contact with any receptor and if adverse effects exist for living beings and the environment. The results showed significant differences among the three types of tests done but, in all cases, the concentrations needed to reflect toxicity effect on organisms were around 20 -70 (Cu and Ni) to 1000 (Zn) times higher than the levels of the control soils. The sensitivity order of the bio-assay was: (1) < (3) < (2). We would like to thank Spanish government-MICINN for partial funding and support (MICINN, project CGL2006-09776).

  2. Biological diversity of Salix taxa in Cu, Pb and Zn phytoextraction from soil.

    Science.gov (United States)

    Mleczek, Mirosław; Rutkowski, Paweł; Goliński, Piotr; Kaczmarek, Zygmunt; Szentner, Kinga; Waliszewska, Bogusława; Stolarski, Mariusz; Szczukowski, Stefan

    2017-02-01

    The aim of the study was to estimate the efficiency of copper (Cu), lead (Pb) and zinc (Zn) phytoextraction by 145 Salix taxa cultivated in an area affected by industrial activity. Survivability and biomass of plants were also analyzed. The highest Cu, Pb and Zn content in shoots was 33.38 ± 2.91 (S. purpurea × viminalis 8), 24.64 ± 1.97 (S. fragilis 1) and 58.99 ± 4.30 (S. eriocephala 7) mg kg -1 dry weight, respectively. In the case of unwashed leaves, the highest content of these metals was 135.06 ± 8.14 (S. purpurea 26), 67.98 ± 5.27 (S. purpurea 45) and 142.56 ± 12.69 (S. alba × triandra 2) mg kg -1 dw, while in washed leaves it was 106.02 ± 11.12 (S. purpurea 45), 55.06 ± 5.75 (S. purpurea 45) and 122.87 ± 12.33 (S. alba × triandra 2) mg kg -1 dw, respectively. The differences between the highest and lowest values for Cu, Pb and Zn were 545%, 20500% and 535% in shoots; 2692%, 2560% and 7500% in unwashed leaves; and 3286%, 2221% and 6950% in washed leaves, respectively. S. acutifolia was able to effectively accumulate all three metals jointly, producing shoots that were well developed in both length and diameter when compared with the other tested willows-an ability that would suggest its high suitability for practical application.

  3. Assessment of Pb, Zn, Cu, Ni and Cr in vegetables grown around Zanjan

    Directory of Open Access Journals (Sweden)

    A. Afshari

    2017-05-01

    Full Text Available This study was conducted aimed to assess the potential risk of heavy metals on human health resulting from consumption of vegetables. To this end, the vegetables grown around town and industrial center of Zanjan were sampled randomly. Plant samples were digested using hydrochloric acid (HCL 2 M and concentration of elements (Pb, Zn, Cu, Ni and Cr were recorded by atomic absorption. Obtained means of heavy metals in all vegetables (N= 32 for Zn, Pb, Cu, Ni and Cr is 98.8, 31.9, 19.3, 4.4 and 2.3 mg/kg, respectively. The highest amount of metal pollution index (MPI in the basil and the lowest was observed in the garden cress (respectively 16.46 and 4.88. Daily intake (EDI for zinc, copper and chromium in all age groups was lower than the provisional tolerable daily intake (PTDI. This amount for nickel was 2, 1.6 and 1.3 %, and for Pb 28.1, 22 and 19 % higher than PTDI in children, adults and seniors, respectively. The potential risk (THQ was calculated in all age groups as Pb>>Cu>Zn>Ni>Cr. The potential risks (THQ of chromium, nickel and zinc were calculated lower than 1, for copper a bit more of 1 and for lead much higher than 1. Health index (HI for children, adults and the elderly was estimated 31.331, 24.58 and 21.14, respectively, with the largest contribution of the lead (89.7%.

  4. Differential Scanning Calorimetry and Thermodynamic Predictions—A Comparative Study of Al-Zn-Mg-Cu Alloys

    Directory of Open Access Journals (Sweden)

    Gernot K.-H. Kolb

    2016-08-01

    Full Text Available Al-Zn-Mg-Cu alloys are widely used in aircraft applications because of their superior mechanical properties and strength/weight ratios. Commercial Al-Zn-Mg-Cu alloys have been intensively studied over the last few decades. However, well-considered thermodynamic calculations, via the CALPHAD approach, on a variation of alloying elements can guide the fine-tuning of known alloy systems and the development of optimized heat treatments. In this study, a comparison was made of the solidus temperatures of different Al-Zn-Mg-Cu alloys determined from thermodynamic predictions and differential scanning calorimetry (DSC measurements. A variation of the main alloying elements Zn, Mg, and Cu generated 38 experimentally produced alloys. An experimental determination of the solidus temperature via DSC was carried out according to a user-defined method, because the broad melting interval present in Al-Zn-Mg-Cu alloys does not allow the use of the classical onset method for pure substances. The software algorithms implemented in FactSage®, Pandat™, and MatCalc with corresponding commercially available databases were deployed for thermodynamic predictions. Based on these investigations, the predictive power of the commercially available CALPHAD databases and software packages was critically reviewed.

  5. Tolerance and hyperaccumulation of a mixture of heavy metals (Cu, Pb, Hg, and Zn) by four aquatic macrophytes.

    Science.gov (United States)

    Romero-Hernández, Jorge Alberto; Amaya-Chávez, Araceli; Balderas-Hernández, Patricia; Roa-Morales, Gabriela; González-Rivas, Nelly; Balderas-Plata, Miguel Ángel

    2017-03-04

    In the present investigation, four macrophytes, namely Typha latifolia (L.), Lemna minor (L.), Eichhornia crassipes (Mart.) Solms-Laubach, and Myriophyllum aquaticum (Vell.) Verdc, were evaluated for their heavy metal (Cu, Pb, Hg, and Zn) hyperaccumulation potential under laboratory conditions. Tolerance analyses were performed for 7 days of exposure at five different treatments of the metals mixture (Cu +2 , Hg +2 , Pb +2 , and Zn +2 ). The production of chlorophyll and carotenoids was determined at the end of each treatment. L. minor revealed to be sensitive, because it did not survive in all the tested concentrations after 72 hours of exposure. E. crassipes and M. aquaticum displayed the highest tolerance to the metals mixture. For the most tolerant species of aquatic macrophytes, The removal kinetics of E. crassipes and M. aquaticum was carried out, using the following mixture of metals: Cu (0.5 mg/L) and Hg, Pb, and Zn 0.25 mg/L. The obtained results revealed that E. crassipes can remove 99.80% of Cu, 97.88% of Pb, 99.53% of Hg, and 94.37% of Zn. M. aquaticum withdraws 95.2% of Cu, 94.28% of Pb, 99.19% of Hg, and 91.91% of Zn. The obtained results suggest that these two species of macrophytes could be used for the phytoremediation of this mixture of heavy metals from the polluted water bodies.

  6. Understanding lattice defects to influence ferromagnetic order of ZnO nanoparticles by Ni, Cu, Ce ions

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Kuldeep Chand, E-mail: dkuldeep.physics@gmail.com [Department of Physics, Panjab University, Chandigarh 160014 (India); Kotnala, R.K., E-mail: rkkotnala@gmail.com [CSIR-National Physical Laboratory, New Delhi 110012 (India)

    2017-02-15

    Future spintronics technologies based on diluted magnetic semiconductors (DMS) will rely heavily on a sound understanding of the microscopic origins of ferromagnetism in such materials. It remains unclear, however, whether the ferromagnetism in DMS is intrinsic - a precondition for spintronics - or due to dopant clustering. For this, we include a simultaneous doping from transition metal (Ni, Cu) and rare earth (Ce) ions in ZnO nanoparticles that increase the antiferromagnetic ordering to achieve high-T{sub c} ferromagnetism. Rietveld refinement of XRD patterns indicate that the dopant ions in ZnO had a wurtzite structure and the dopants, Ni{sup 2+}, Cu{sup 2+}, Ce{sup 3+} ions, are highly influenced the lattice constants to induce lattice defects. The Ni, Cu, Ce ions in ZnO have nanoparticles formation than nanorods was observed in pure sample. FTIR involve some organic groups to induce lattice defects and the metal-oxygen bonding of Zn, Ni, Cu, Ce and O atoms to confirm wurtzite structure. Raman analysis evaluates the crystalline quality, structural disorder and defects in ZnO lattice with doping. Photoluminescence spectra have strong near-band-edge emission and visible emission bands responsible for defects due to oxygen vacancies. The energy band gap is calculated using Tauc relation. Room temperature ferromagnetism has been described due to bound magnetic polarons formation with Ni{sup 2+}, Cu{sup 2+}, Ce{sup 3+} ions in ZnO via oxygen vacancies. The zero field and field cooling SQUID measurement confirm the strength of antiferromagnetism in ZnO. The field cooling magnetization is studied by Curie-Weiss law that include antiferromagnetic interactions up to low temperature. The XPS spectra have involve +3/+4 oxidation states of Ce ions to influence the observed ferromagnetism. - Graphical abstract: The lattice defects/vacancies attributed by Ni and Ce ions in the wurtzite ZnO structure are responsible in high T{sub c} -ferromagnetism due to long-range magnetic

  7. Electrochemiluminescence assay of Cu2+ by using one-step electrodeposition synthesized CdS/ZnS quantum dots.

    Science.gov (United States)

    Zhao, Guanhui; Li, Xiaojian; Zhao, Yongbei; Li, Yueyuan; Cao, Wei; Wei, Qin

    2017-08-21

    A sensitive and selective method was proposed to detect Cu 2+ based on the electrochemiluminescence quenching of CdS/ZnS quantum dots (QDs). Herein, CdS/ZnS QDs were one-step electrodeposited directly on a gold electrode from an electrolyte (containing Cd(NO 3 ) 2 , Zn(NO 3 ) 2 , EDTA and Na 2 S 2 O 3 ) by cycling the potential from 0 to -1.8 V. The prepared CdS/ZnS QDs exhibited excellent solubility and strong and stable cathodic ECL activity. Meanwhile, Nafion was used to immobilize CdS/ZnS QDs. The quenching effect