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Sample records for nickel supportes prepares

  1. Preparation of self-supporting metallic foils of nickel isotopes

    International Nuclear Information System (INIS)

    Sugai, Isao.

    1975-01-01

    This is the fourth report on the practical methods of target preparation for use in low energy nuclear experiments following the previous one (INS-J-150). An electroplating method has been developed as a dependable and reproducible technique for making self-supporting metallic foils of nickel in the thickness range of 0.5 to 10 mg/cm 2 . The procedures minimized the necessary amount of material so that nickel isotopes could be processed economically. Impurity contamination of the nickel foils during the electroplating process was less than 500 ppm, and the thickness variation in each foil was less than 3% of the central thickness. (auth.)

  2. Preparation by thermal evaporation under vacuum of thin nickel films without support

    International Nuclear Information System (INIS)

    Prugne, P.; Garin, P.; Lechauguette, G.

    1959-01-01

    This note deals with the preparation of nickel films without support by means of the technique described but using a new evaporation apparatus. In effect it was necessary, in order to obtain these nickel films, to modify the thermal evaporation conditions. An attempt to obtain a film without support after evaporation in a conventional apparatus led almost invariably to defeat. This appeared to be due to the high concentration of oxygen and of various vapors (diffusion pumps, degassing, etc.) present in the residual atmosphere of the conventional evaporation system. Reprint of a paper published in 'Le Vide, N. 74, March-April 1958, p. 82-83

  3. Hydrogenation of Levulinic Acid over Nickel Catalysts Supported on Aluminum Oxide to Prepare γ-Valerolactone

    Directory of Open Access Journals (Sweden)

    Jie Fu

    2015-12-01

    Full Text Available Four types of nickel catalysts supported on aluminum oxide (Ni/Al2O3 with different nickel loadings were synthesized using the co-precipitation method and were used for the hydrogenation of levulinic acid (LA to prepare γ-valerolactone (GVL. The synthesized Ni/Al2O3 catalysts exhibited excellent catalytic activity in dioxane, and the activity of the catalysts was excellent even after being used four times in dioxane. The catalytic activity in dioxane as a solvent was found to be superior to the activity in water. Nitrogen physisorption, X-ray diffraction, and transmission electron microscopy were employed to characterize the fresh and used catalysts. The effects of the nickel loading, temperature, hydrogen pressure, and substrate/catalyst ratio on the catalytic activity were investigated.

  4. Nickel foam-supported polyaniline cathode prepared with electrophoresis for improvement of rechargeable Zn battery performance

    Science.gov (United States)

    Xia, Yang; Zhu, Derong; Si, Shihui; Li, Degeng; Wu, Sen

    2015-06-01

    Porous nickel foam is used as a substrate for the development of rechargeable zinc//polyaniline battery, and the cathode electrophoresis of PANI microparticles in non-aqueous solution is applied to the fabrication of Ni foam supported PANI electrode, in which the corrosion of the nickel foam substrate is prohibited. The Ni foam supported PANI cathode with high loading is prepared by PANI electrophoretic deposition, and followed by PANI slurry casting under vacuum filtration. The electrochemical charge storage performance for PANI material is significantly improved by using nickel foam substrate via the electrophoretic interlayer. The specific capacity of the nickel foam-PANI electrode with the electrophoretic layer is higher than the composite electrode without the electrophoretic layer, and the specific capacity of PANI supported by Ni foam reaches up to 183.28 mAh g-1 at the working current of 2.5 mA cm-2. The present electrophoresis deposition method plays the facile procedure for the immobilization of PANI microparticles onto the surface of non-platinum metals, and it becomes feasible to the use of the Ni foam supported PANI composite cathode for the Zn/PANI battery in weak acidic electrolyte.

  5. Study of Supported Nickel Catalysts Prepared by Aqueous Hydrazine Method. Hydrogenating Properties and Hydrogen Storage: Support Effect. Silver Additive Effect

    International Nuclear Information System (INIS)

    Wojcieszak, R.

    2006-06-01

    We have studied Ni or NiAg nano-particles obtained by the reduction of nickel salts (acetate or nitrate) by hydrazine and deposited by simple or EDTA-double impregnation on various supports (γ-Al 2 O 3 , amorphous or crystallized SiO 2 , Nb 2 O 5 , CeO 2 and carbon). Prepared catalysts were characterized by different methods (XRD, XPS, low temperature adsorption and desorption of N 2 , FTIR and FTIR-Pyridine, TEM, STEM, EDS, H 2 -TPR, H 2 -adsorption, H 2 -TPD, isopropanol decomposition) and tested in the gas phase hydrogenation of benzene or as carbon materials in the hydrogen storage at room temperature and high pressure. The catalysts prepared exhibited better dispersion and activity than classical catalysts. TOF's of NiAg/SiO 2 or Ni/carbon catalysts were similar to Pt catalysts in benzene hydrogenation. Differences in support acidity or preparation method and presence of Ag as metal additive play a crucial role in the chemical reduction of Ni by hydrazine and in the final properties of the materials. Ni/carbon catalysts could store significant amounts of hydrogen at room temperature and high pressure (0.53%/30 bars), probably through the hydrogen spillover effect. (author)

  6. Preparation and characterization of alumina supported nickel-oxalate catalyst for the hydrodeoxygenation of oleic acid into normal and iso-octadecane biofuel

    International Nuclear Information System (INIS)

    Ayodele, O.B.; Togunwa, Olayinka S.; Abbas, Hazzim F.; Daud, Wan Mohd Ashri Wan

    2014-01-01

    Highlights: • Preparation of nickel oxalate complex as catalyst precursor. • Incorporation of nickel oxalate complex into alumina support. • Characterization of the alumina supported nickel oxalate catalyst. • Hydrodeoxygenation of oleic acid with nickel oxalate catalyst. • Nickel oxalate catalyst reusability studies. - Abstract: In this study, nickel II oxalate complex (NiOx) was prepared by functionalization of nickel with oxalic acid (OxA) and incorporated into Al 2 O 3 to synthesize alumina supported nickel oxalate (NiOx/Al 2 O 3 ) catalyst for the hydrodeoxygenation (HDO) of oleic acid (OA) into biofuel. The synthesized NiOx/Al 2 O 3 was characterized and the X-ray fluorescence and elemental dispersive X-ray results showed that NiOx was successfully incorporated into the structure of Al 2 O 3 . The X-ray diffraction and Raman spectroscopy results confirmed that highly dispersed Ni species are present in the NiOx/Al 2 O 3 due to the functionalization with OxA. The catalytic activity of the NiOx/Al 2 O 3 on the HDO of OA produced a mixture of 21% iso-C18 and 72% n-C18 at a 360 °C, 20 bar, 30 mg NiOx/Al 2 O 3 loading pressure and gas flow rate of 100 mL/min. The presence of i-C 18 was ascribed to the OxA functionalization which increased the acidity of NiOx/Al 2 O 3 . The NiOx/Al 2 O 3 reusability study showed consistent HDO ability after 5 runs. These results are promising for further research into biofuel production for commercialization

  7. Preparation and characterization of reduced graphene oxide supported nickel oxide nanoparticle-based platform for sensor applications

    Science.gov (United States)

    Roychoudhury, Appan; Prateek, Arneish; Basu, Suddhasatwa; Jha, Sandeep Kumar

    2018-03-01

    A nanostructured composite film comprising reduced graphene oxide (rGO) and nickel oxide (NiO) nanoparticles (NPs) has been prepared and utilized for development of a simple yet efficient sensor for detection of dopamine and epinephrine in a single run. The hybrid material rGO-NiO nanocomposite was synthesized chemically, and the formation of nanocomposite was confirmed via X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman, UV-Vis, and Fourier transform infrared (FTIR) spectroscopic techniques. The incorporation of NiO NPs on rGO support was found to provide improved sensing characteristics at electrode interface due to enhanced electron mobility on rGO sheet and high catalytic activity of NiO NPs. Subsequently, the synthesized rGO-NiO nanocomposite was deposited onto indium tin oxide (ITO)-coated glass substrate by simple drop-casting method, and the electrode was characterized through atomic force microscopy (AFM) and scanning electron microscopic (SEM) studies. After optimization of experimental conditions electrochemically for its high sensitivity, the fabricated rGO-NiO/ITO electrode was used for simultaneous detection of dopamine and epinephrine by square wave voltammetry (SWV) method. The results showed high sensitivity of 0.545 and 0.638 μA/μM for dopamine and epinephrine respectively in a broad linear range of 0.5-50 μM. Moreover, remarkable detection limits of 0.495 and 0.423 μM were found for dopamine and epinephrine, and the developed sensor exhibited a wide separation of 380 mV between the respective detection peaks of dopamine and epinephrine. Beside this, the proposed sensor was successfully applied in presence of high concentration of interfering agents, ascorbic acid and uric acid, and validated with real serum samples.

  8. Silica supported nickel catalysts : Tracer studies.

    OpenAIRE

    Sharratt, Andrew Paul.

    1991-01-01

    A series of silica supported catalysts were prepared by impregnation of the support materials with a nickel(II) nitrate precursor under standard conditions. The catalysts and silicas were characterised using temperature programmed reduction (TPR) techniques, neutron diffraction, small angle neutron scattering, and 29Si magic angle spinning nuclear magnetic resonance (MAS-NMR). These analyses revealed one significant variable in the silicas:- the surface concentration of strained siloxane ring...

  9. Study of Supported Nickel Catalysts Prepared by Aqueous Hydrazine Method. Hydrogenating Properties and Hydrogen Storage: Support Effect. Silver Additive Effect; Catalyseurs de nickel supportes prepares par la methode de l'hydrazine aqueuse. Proprietes hydrogenantes et stockage d'hydrogene. Effet du support. Effet de l'ajout d'argent

    Energy Technology Data Exchange (ETDEWEB)

    Wojcieszak, R

    2006-06-15

    We have studied Ni or NiAg nano-particles obtained by the reduction of nickel salts (acetate or nitrate) by hydrazine and deposited by simple or EDTA-double impregnation on various supports ({gamma}-Al{sub 2}O{sub 3}, amorphous or crystallized SiO{sub 2}, Nb{sub 2}O{sub 5}, CeO{sub 2} and carbon). Prepared catalysts were characterized by different methods (XRD, XPS, low temperature adsorption and desorption of N{sub 2}, FTIR and FTIR-Pyridine, TEM, STEM, EDS, H{sub 2}-TPR, H{sub 2}-adsorption, H{sub 2}-TPD, isopropanol decomposition) and tested in the gas phase hydrogenation of benzene or as carbon materials in the hydrogen storage at room temperature and high pressure. The catalysts prepared exhibited better dispersion and activity than classical catalysts. TOF's of NiAg/SiO{sub 2} or Ni/carbon catalysts were similar to Pt catalysts in benzene hydrogenation. Differences in support acidity or preparation method and presence of Ag as metal additive play a crucial role in the chemical reduction of Ni by hydrazine and in the final properties of the materials. Ni/carbon catalysts could store significant amounts of hydrogen at room temperature and high pressure (0.53%/30 bars), probably through the hydrogen spillover effect. (author)

  10. Carbon Monoxide Chemisorption- Characterization and Testing of Prepared Nickel Catalysts for Amination of Ethanol

    OpenAIRE

    Hanafi Setiawan, Achmad

    1994-01-01

    Three types of nickel metal catalyst supported on silica gel have been prepared using impregnation, ion exchanged sodium hydroxide and ion exchanged ammonia methods, in order to investigate the influence of preparation methods on metal dispersion and their activities for amination of ethanol. All the catalyst samples had a nominal nickel loading of 5 % (w/w). After preparation, the catalysts were activated by a drying stage followed by calcination and reduction. The result of transferring the...

  11. Polymer-Supported Raney Nickel Catalysts for Sustainable Reduction Reactions

    Directory of Open Access Journals (Sweden)

    Haibin Jiang

    2016-06-01

    Full Text Available Green is the future of chemistry. Catalysts with high selectivity are the key to green chemistry. Polymer-supported Raney catalysts have been found to have outstanding performance in the clean preparation of some chemicals. For example, a polyamide 6-supported Raney nickel catalyst provided a 100.0% conversion of n-butyraldehyde without producing any detectable n-butyl ether, the main byproduct in industry, and eliminated the two main byproducts (isopropyl ether and methyl-iso-butylcarbinol in the hydrogenation of acetone to isopropanol. Meanwhile, a model for how the polymer support brought about the elimination of byproducts is proposed and confirmed. In this account the preparation and applications of polymer-supported Raney catalysts along with the corresponding models will be reviewed.

  12. Preparation of fine Ni powders from nickel hydrazine complex

    International Nuclear Information System (INIS)

    Park, Jung Woo; Chae, Eun H.; Kim, Sang H.; Lee, Jong Ho; Kim, Jeong Wook; Yoon, Seon Mi; Choi, Jae-Young

    2006-01-01

    Fine nickel powders with narrow size distribution have been prepared from the reduction of nickel hydrazine complexes in aqueous solution. The pure nickel hydrazine complexes, [Ni(N 2 H 4 ) 3 ]Cl 2 were prepared with the molar ratio of N 2 H 4 /Ni 2+ = 4.5, while a mixture of complexes, such as Ni(N 2 H 4 ) 2 Cl 2 , [Ni(N 2 H 4 ) 3 ]Cl 2 , and [Ni(NH 3 ) 6 ]Cl 2 were formed with N 2 H 4 /Ni 2+ 2+ to metallic Ni powder proceeded via the formation of nickel hydroxide which was reduced by hydrazine liberated from the ligand exchange reaction between the nickel hydrazine complex and NaOH. The standard deviation of the particle size decreased with the decreasing molar concentration of nickel hydrazine complex while the mean particle size increased. As the amount of hydrazine increased, the surface roughness of the particles was improved significantly due to the catalytic decomposition of the excess hydrazine at the surface of the nickel particle. It was found that average particle size could be controlled from 150 to 380 nm by adjusting the reaction molar ratio and temperature

  13. PREPARATION OF NICKEL - COBALT SPINEL OXIDES NixCO3 ...

    African Journals Online (AJOL)

    ABSTRACT. A comparative study of two electro-physical properties (porosity and electrical conductivity) of binary nickel cobalt oxides electrodes with spinels mixed oxides NixCo3-xO4 as active matter, was carried out. Four different routes were used to prepare spinel-type NixCo3-xO4 (0 ≤ x ≤. 2.5) compounds in order to ...

  14. SBA-15-Supported Nickel Phosphide Hydrotreating Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Korányi, T.I.; Vít, Zdeněk; Poduval, D.G.; Ryoo, R.; Kim, H.S.; Hensen, E.J. M.

    2008-01-01

    Roč. 253, 1 (2008) , s. 119-131 ISSN 0021-9517 R&D Projects: GA ČR(CZ) GA104/06/0870 Institutional research plan: CEZ:AV0Z40720504 Keywords : nickel phosphide * sba-15 * hydrodesulfurization Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.167, year: 2008

  15. Polymer supported nickel complex: Synthesis, structure and catalytic ...

    Indian Academy of Sciences (India)

    Polystyrene support; catalysis; organometallic catalyst, nickel complex; phenol oxidation. 1. Introduction. Schiff base catalysts have a great impact on both the scholastic research and polymer industry. Schiff base complexes have shown adaptable applications in different organic transformation reactions such as oxidation,1 ...

  16. Preparation, characterization and wear behavior of carbon coated magnesium alloy with electroless plating nickel interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Yan [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Li, Zhuguo, E-mail: lizg@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China); Feng, Kai, E-mail: fengkai@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China); Guo, Xingwu [National Engineering Research Center of Light Alloys Net Forming (LAF), School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhou, Zhifeng [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong (China); Dong, Jie [National Engineering Research Center of Light Alloys Net Forming (LAF), School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wu, Yixiong [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China)

    2015-02-01

    Highlights: • The carbon film with nickel interlayer (Ni + C coating) is deposited on GW83. • In Ni + C composite coating the carbon coating has good adhesion with the nickel interlayer. • The wear track of Ni + C coating is narrower compared to the bare one. • The wear resistance of GW83 is greatly improved by the Ni + C coating. - Abstract: Poor wear resistance of rare earth magnesium alloys has prevented them from wider application. In this study, composite coating (PVD carbon coating deposited on electroless plating nickel interlayer) is prepared to protect GW83 magnesium alloys against wear. The Ni + C composite coating has a dense microstructure, improved adhesion strength and hardness due to the effective support of Ni interlayer. The wear test result shows that the Ni + C composite coating can greatly prolong the wear life of the magnesium alloy. The wear track of the Ni + C coated magnesium alloy is obviously narrower and shows less abrasive particles as compared with the bare one. Abrasive wear is the wear mechanism of the coatings at the room temperature. In conclusion, the wear resistance of the GW83 magnesium alloy can be greatly improved by the Ni + C composite coating.

  17. Preparation and thermal stability of nickel nanowires via self ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Nickel nanowires were synthesized via a template-free method in an aqueous solution system combined with chemical reduction and magnetic field. The suitable concentration of Ni ions and reaction time were controlled in order to obtain nickel wires with uniform sizes. The products were characterized by X-ray.

  18. Preparation and evaluation of mesoporous nickel and manganese ...

    Indian Academy of Sciences (India)

    YALDA RAMEZANI

    2018-02-01

    Feb 1, 2018 ... Abstract. In this paper, Ni-Mn catalysts supported on mesoporous nanocrystalline γ -Al2O3 were prepared and employed in carbon dioxide reforming of methane for the production of synthesis gas. The physicochemical properties of the catalysts were determined by XRD, BET, TPO and SEM techniques.

  19. Preparation and evaluation of mesoporous nickel and manganese ...

    Indian Academy of Sciences (India)

    In this paper, Ni-Mn catalysts supported on mesoporous nanocrystalline γ -Al2O3 were prepared and employed in carbon dioxide reforming of methane for the production of synthesis gas. The physicochemical properties of the catalysts were determined by XRD, BET, TPO and SEM techniques. The obtained resultsrevealed ...

  20. Preparation and characterization of nanoplatelets of nickel hydroxide and nickel oxide

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Gentao [CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space of Sciences, University of Science and Technology of China, Hefei 230026, Anhui (China)]. E-mail: gtzhou@ustc.edu.cn; Yao Qizhi [School of Chemistry and Materials, University of Science and Technology of China, Hefei 230026, Anhui (China); Wang Xinchen [Department of Chemistry, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China); Yu, Jimmy C. [Department of Chemistry, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China)

    2006-08-01

    A novel room-temperature coordination-precipitation technique was successfully developed for the synthesis of nickel hydroxide (theophrastite) nanoplatelets. This method has great potential for large-scale industrial production owing to facile size-controlled and low-cost. This platelet-like nickel hydroxide precursor can readily be converted to nickel oxide (bunsenite) nanoplatelets after 400 deg. C calcining. The synthesized products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetry-differential thermal analysis (TG-DTA) and X-ray photoelectron spectroscopy (XPS) techniques. The thickness of {beta}-Ni(OH){sub 2} nanoplatelets can be controlled by changing concentration of precipitant NaOH in the presence of ethylenediamine. The formation of Ni(en){sub 3} {sup 2+} complex ions in solution prior to precipitating nickel hydroxide may play a crucial role in controlling phase composition of resulting precipitate.

  1. Nickel Dermatitis - Nickel Excretion

    DEFF Research Database (Denmark)

    Menné, T.; Thorboe, A.

    1976-01-01

    Nickel excretion in urine in four females -sensitive to nickel with an intermittent dyshidrotic eruption was measured with flameless atomic absorption. Excretion of nickel was found to be increased in association with outbreaks of vesicles. The results support the idea that the chronic condition...... was maintained by ingestion of nickel in food....

  2. Nickel/carbon nanofibers composite electrodes as supercapacitors prepared by electrospinning

    International Nuclear Information System (INIS)

    Li Jian; Liu, En-hui; Li Wen; Meng Xiangyun; Tan Songting

    2009-01-01

    Nickel-embedded carbon nanofibers were prepared by the processes of stabilization and carbonation after electrospinning a mixture solution of nickel acetate and polyacrylonitrile in N,N-dimethylformamide. The surface morphology and structure of composites were examined by scanning electron microscope (SEM) and X-ray diffraction (XRD). Compared with performances of composite electrodes with different mass ratios of nickel and carbon by cyclic voltammetry (CV) and chronopotentiogram test, the results show that the introduction of a proper proportion of nickel into carbon could enhance both specific capacitance (SC) and electrochemical stability. The specific capacitance of the carbon nanofiber electrode without the Ni loading was 50 F/g, while that of 22.4 wt.% Ni/carbon electrode increased to 164 F/g. The improved specific capacitance may be attributed to synergic effects from each pristine component, and the electrochemical catalysis effect of nickel.

  3. Bulk Nanolaminated Nickel: Preparation, Microstructure, Mechanical Property, and Thermal Stability

    Science.gov (United States)

    Liu, Fan; Yuan, Hao; Goel, Sunkulp; Liu, Ying; Wang, Jing Tao

    2018-02-01

    A bulk nanolaminated (NL) structure with distinctive fractions of low- and high-angle grain boundaries ( f LAGBs and f HAGBs) is produced in pure nickel, through a two-step process of primary grain refinement by equal-channel angular pressing (ECAP), followed by a secondary geometrical refinement via liquid nitrogen rolling (LNR). The lamellar boundary spacings of 2N and 4N nickel are refined to 40 and 70 nm, respectively, and the yield strength of the NL structure in 2N nickel reaches 1.5 GPa. The impacts of the deformation path, material purity, grain boundary (GB) misorientation, and energy on the microstructure, refinement ability, mechanical strength, and thermal stability are investigated to understand the inherent governing mechanisms. GB migration is the main restoration mechanism limiting the refinement of an NL structure in 4N nickel, while in 2N nickel, shear banding occurs and mediates one-fifth of the total true normal rolling strain at the mesoscale, restricting further refinement. Three typical structures [ultrafine grained (UFG), NL with low f LAGBs, and NL with high f LAGBs] obtained through three different combinations of ECAP and LNR were studied by isochronal annealing for 1 hour at temperatures ranging from 433 K to 973 K (160 °C to 700 °C). Higher thermal stability in the NL structure with high f LAGBs is shown by a 50 K (50 °C) delay in the initiation temperature of recrystallization. Based on calculations and analyses of the stored energies of deformed structures from strain distribution, as characterized by kernel average misorientation (KAM), and from GB misorientations, higher thermal stability is attributed to high f LAGBs in this type of NL structure. This is confirmed by a slower change in the microstructure, as revealed by characterizing its annealing kinetics using KAM maps.

  4. XPS study of silver, nickel and bimetallic silver-nickel nanoparticles prepared by seed-mediated growth

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, Pilar, E-mail: pilar.prieto@uam.es [Departamento de Fisica Aplicada and Instituto de Ciencia de Materiales ' Nicolas Cabrera' , Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Nistor, Valentin [Departamento de Fisica Aplicada and Instituto de Ciencia de Materiales ' Nicolas Cabrera' , Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Nouneh, Khalid [Institute for Nanomaterials and Nanotechnology (INANOTECH), Moroccan Foundation for Advanced Science, Innovation and Research (MAScIR), ENSET, Av. Armee Royale, 10100, Rabat (Morocco); Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8520 (Japan); Oyama, Munetaka [Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8520 (Japan); Abd-Lefdil, Mohammed [Laboratory of Materials Physics, University Mohammed V-Agdal, Rabat (Morocco); Diaz, Raquel [Departamento de Fisica Aplicada and Instituto de Ciencia de Materiales ' Nicolas Cabrera' , Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer We have prepared Ag, Ni and AgNi NPs by derived seed-mediated growth method. Black-Right-Pointing-Pointer The combined use of optical, structural and chemical characterization techniques allows to determine the presence of core-shell structures. Black-Right-Pointing-Pointer The oxidation states of Ag and Ni at the outer layers of the NPs have been studied by XPS. Black-Right-Pointing-Pointer Ag NPs are purely metallic with a fcc structure. Black-Right-Pointing-Pointer Ni NPs are formed by Ni core-NiO + Ni(OH){sub 2} shell structure. Black-Right-Pointing-Pointer Ag core-NiO + Ni(OH){sub 2} shell structure is determined for AgNi NPs, with oxidized silver atoms at the interface. - Abstract: The chemical structure of silver, nickel and bimetallic silver-nickel nanoparticles, i.e. Ag, Ni and AgNi NPs, with sizes {<=}35 nm, obtained by derived seed-mediated growth method on transparent and conductive indium tin oxide (ITO) substrates, has been studied by a comparative X-ray photoelectron spectroscopy (XPS) analysis of Ag 3d, Ni 2p and O1s core levels in combination with X-ray diffraction and optical absorption spectroscopy in the visible range. XPS indicates that the surface of Ag NPs is not oxidized, while Ni NPs are clearly oxidized to nickel oxide and hydroxide. Absorptions at 384 and 600 nm in Ni optical spectrum are consistent with the presence of nickel in oxidized state; however the presence of metallic Ni 2p signal in Ni XPS spectrum indicates that a metallic nickel core is still present. In the case of bimetallic AgNi NPs, the XPS results are consistent with the presence of metallic silver core surrounded by NiO + Ni(OH){sub 2} shell. XPS spectra also show the presence of Ag{sub 2}O at the interface between the Ag metallic core and the oxidized nickel shell. XRD patterns of AgNi and Ag NPs show the typical fcc structure of metallic silver, confirming the presence of Ag metallic core in AgNi NPs. The surface plasmon

  5. Well-defined mono(η3-allyl)nickel complex MONi(η3-C3H5) (M = Si or Al) grafted onto silica or alumina: A molecularly dispersed nickel precursor for syntheses of supported small size nickel nanoparticles

    KAUST Repository

    Li, Lidong

    2014-01-01

    Preparing evenly-dispersed small size nickel nanoparticles over inert oxides remains a challenge today. In this context, a versatile method to prepare supported small size nickel nanoparticles (ca. 1-3 nm) with narrow size distribution via a surface organometallic chemistry (SOMC) route is described. The grafted mono(η3-allyl)nickel complexes MONi(η 3-C3H5) (M = Si or Al) as precursors are synthesized and fully characterized by elemental analysis, FTIR spectroscopy and paramagnetic solid-state NMR. © 2014 the Partner Organisations.

  6. Preparation and Study on Nickel Oxide Reduction of Polyacrylonitrile-Based Carbon Nanofibers by Thermal Treatment.

    Science.gov (United States)

    Lee, Yeong Ju; Kim, Hyun Bin; Jeun, Joon Pyo; Lee, Dae Soo; Koo, Dong Hyun; Kang, Phil Hyun

    2015-08-01

    Carbon materials containing magnetic nanopowder have been attractive in technological applications such as electrochemical capacitors and electromagnetic wave shielding. In this study, polyacrylonitrile (PAN) fibers containing nickel nanoparticles were prepared using an electrospinning method and thermal stabilization. The reduction of nickel oxide was investigated under a nitrogen atmosphere within a temperature range of 600 to 1,000 °C. Carbon nanofibers containing nickel nanoparticles were characterized by FE-SEM, EDS, XRD, TGA, and VSM. It was found that nickel nanoparticles were formed by a NiO reduction in PAN as a function of the thermal treatment. These results led to an increase in the coercivity of nanofibers and a decrease in the remanence magnetization.

  7. EFFECT OF PREPARATION METHOD OF Ni CATALYST USING BENTONITE AS THE SUPPORT MATERIAL

    Directory of Open Access Journals (Sweden)

    Hery Haerudin

    2010-06-01

    Full Text Available Nickel catalyst has been prepared impregnation and precipitation with nickel content of 20% and 25% each using bentonite as support material. The effects of the preparation method were studied using temperature programmed oxidation (TPO and temperature programmed reduction (TPR and by determination of its specific surface area. The activity of catalysts has been tested in the hydrogenation of palm oil. The catalyst with 20% of nickel and prepared by impregnation shows a single peak at 301°C, compared to catalyst with 25% of nickel prepared by the same method which has a peak at 304°C and a shoulder at 330°C. The reduction curves of both catalysts, those are prepared by impregnation, show a homogeneity indicated by a high main peak at 426°C (20% Ni and 430°C (25% Ni. The 25% nickel catalyst by impregnation has a shoulder at 508°C. The catalysts prepared by precipitation show peaks at 508°C and 661°C for 20% of Ni and peaks at 419°C and 511°C for 25% of Ni. The reduction curves of catalysts prepared by precipitation are significantly different from each other. Those are also very different comparing to the reduction curve of impregnated catalyst. The 20% precipitated nickel catalyst has a single peak at 540°C, but the 25% precipitated nickel catalyst shows peaks at 346°C and 503°C. The differences of peak position among the reduction curves of catalysts resulted in the differences of catalyst activities with the following order 20% Ni (impregnation > 25% Ni (impregnation > 20% Ni (precipitation > 25% Ni (precipitation.   Keywords: bentonite, nickel catalyst, hidrogenation

  8. Thermocatalytic decomposition of methane/methanol mixture for hydrogen production: Effect of nickel loadings on alumina support

    Science.gov (United States)

    Awad, Ali; Salam, Abdus; Abdullah, Bawadi

    2017-10-01

    Hydrogen produced by thermocatalytic decomposition of methane is termed as clean and alternative fuel however high reaction temperature and fast catalyst deactivation limitize the efficiency of this process. In this study nickel based catalyst supported on alumina with various Ni loadings were prepared by impregnation method and employed for TCD of methane/methanol mixture for hydrogen production. Surface area and pore volume were decreased by increasing the amount of nickel loading on alumina. The results revealed that both reaction temperature and nickel loading affected the reaction rates and catalyst deactivation time. Scanning electron microscope (SEM) and Thermogravematric analysis (TGA) were used for characterization of fresh and spent catalyst. Crystalline carbon was formed on the surface of the catalyst and was proved by TGA analysis. Methane yield increased as the reaction temperature was increased but the catalyst deactivation time was decreased as a lot carbon was encapsulated on the surface of the catalyst.

  9. Polymer supported nickel complex: Synthesis, structure and catalytic ...

    Indian Academy of Sciences (India)

    MOBdMBn-Ni] and polystyrene-anchored [P-3-MOBdMBn-Ni] nickel complexes is presented. The free and polymer-anchored metal complexes were synthesized by the reaction of nickel (II) with one molar equivalent of unsupported N N′-bis ...

  10. Preparation and Characterization of Nickel Ferrite-SiO2/Ag Core/Shell Nanocomposites

    Directory of Open Access Journals (Sweden)

    I. G. Blanco-Esqueda

    2015-01-01

    Full Text Available Magnetic composites with silver nanoparticles bonded to their surface were successfully prepared using a simple chemical method. By means of a sol-gel technique, nickel ferrite nanoparticles have been prepared and coated with silica to control and avoid their magnetic agglomeration. The structural and magnetic properties of the nanoparticles were studied in function of the annealing temperature. Then, silver nanoparticles were incorporated by hydrolysis-condensation of tetraethyl orthosilicate, which contains silver nitrate on the surface of the nickel ferrite-SiO2 core/shell. Samples were characterized using X-ray diffraction, IR spectroscopy, SEM, and magnetometry. Results show that the silica covered the nickel ferrite nanoparticles and the silver nanoparticles remain stable in the surface of the composite.

  11. Magnetic nanofilms of nickel prepared at the liquid-liquid interface

    International Nuclear Information System (INIS)

    Varghese, Neenu; Rao, C.N.R.

    2011-01-01

    Highlights: → Formation of nickel thinfims at the organic-aqueous interface at room temperature. → Thickness of nanofilm is ∼20 nm. → Ni nanofilms exhibit superparamagnetic behavior. → Thicker Ni films are obtained at a higher temperature (60 o C). -- Abstract: Thin films of metallic nickel with a thickness of the order of 20 nm have been prepared at the organic-aqueous interface at room temperature by the reaction of nickel cupferronate [Ni(C 6 H 5 N 2 O 2 ) 2 ] in toluene medium and sodium borohydride (NaBH 4 ) in aqueous medium. The films were characterized with transmission electron microscopy, scanning electron microscopy and atomic force microscopy. Thicker Ni films could be prepared by carrying out the reaction at the interface at 60 o C. The Ni nanofilms exhibit superparamagnetic behavior.

  12. Binding of nickel and zinc ions with activated carbon prepared from ...

    African Journals Online (AJOL)

    Activated carbon was prepared from sugar cane fibre by carbonizing at 500 oC for 30 minutes. This was followed by activation with ammonium chloride. The activated carbon was characterised in terms of pH, bulk density, ash content, surface area and surface charge. Equilibrium sorption of nickel and zinc ions by the ...

  13. PREPARATION OF NICKEL - COBALT SPINEL OXIDES Ni x CO 3-x ...

    African Journals Online (AJOL)

    X-ray diffraction patterns showed that the oxides crystallize in a cubic spinel phase. Electrical conductivity as well as porosity depends on the preparation route. KEY WORDS: Nickel cobalt spinel oxides, Porosity, Electrical conductivity, Mixed oxides electrodes, Carbon paste electrode, Pechini sol-gel method. Bull. Chem.

  14. Binary supported nickel catalysts for the deuterium exchange reaction between hydrogen and water vapour

    International Nuclear Information System (INIS)

    Abou El-Nour, F.H.; Belacy, A.

    1982-01-01

    Nickel catalysts supported by Fe 2 O 3 , CuO, MnO and CeO were prepared from the corresponding metal nitrates. Chemical treatment of the catalysts was carried out at room temperature, while thermal treatment was made at 350 0 C. The total surface area of the catalysts was measured by nitrogen adsorption at -195 0 C using the BET equation. The specific metallic surface area was measured by hydrogen chemisorption at liquid nitrogen temperature. The activity of the catalysts was tested for the isotopic exchange reaction of deuterium between hydrogen and water vapour. The results obtained showed that Ni-Fe 2 O 3 , Ni-CuO and Ni-MnO catalysts exhibit catalytic activity for the deuterium exchange between hydrogen and water vapour, while the catalyst supported by CeO has no such activity. (author)

  15. Carbon-encapsulated nickel-iron nanoparticles supported on nickel foam as a catalyst electrode for urea electrolysis

    International Nuclear Information System (INIS)

    Wu, Mao-Sung; Jao, Chi-Yu; Chuang, Farn-Yih; Chen, Fang-Yi

    2017-01-01

    Highlights: • Electrochemical process can purify the urea-rich wastewater, producing hydrogen gas. • Carbon-encapsulated nickel iron nanoparticles (CE-NiFe) are prepared by pyrolysis. • An ultra-thin layer of CE-NiFe nanoparticles is attached to the 3D Ni foam. • CE-NiFe nanoparticles escalate both the urea electrolysis and hydrogen evolution. - Abstract: A cyanide-bridged bimetallic coordination polymer, nickel hexacyanoferrate, could be pyrolyzed to form carbon-encapsulated nickel-iron (CE-NiFe) nanoparticles. The formation of nitrogen-doped spherical carbon shell with ordered mesoporous structure prevented the structural damage of catalyst cores and allowed the migration and diffusion of electrolyte into the hollow carbon spheres. An ultra-thin layer of CE-NiFe nanoparticles could be tightly attached to the three-dimensional macroporous nickel foam (NF) by electrophoretic deposition. The CE-NiFe nanoparticles could lower the onset potential and increase the current density in anodic urea electrolysis and cathodic hydrogen production as compared with bare NF. Macroporous NF substrate was very useful for the urea electrolysis and hydrogen production, which allowed for fast transport of electron, electrolyte, and gas products. The superior electrocatalytic ability of CE-NiFe/NF electrode in urea oxidation and water reduction made it favorable for versatile applications such as water treatment, hydrogen generation, and fuel cells.

  16. 3 D Porous Nickel-Cobalt Nitrides Supported on Nickel Foam as Efficient Electrocatalysts for Overall Water Splitting.

    Science.gov (United States)

    Wang, Yueqing; Zhang, Baohua; Pan, Wei; Ma, Houyi; Zhang, Jintao

    2017-08-30

    Exploring highly efficient and durable bifunctional electrocatalysts from earth-abundant low-cost transition metals is central to obtaining clean hydrogen energy through large-scale electrolytic water splitting. Porous nickel-cobalt nitride nanosheets on macroporous Ni foam (NF) are synthesized through facile electrodeposition followed by a one-step annealing process in a NH 3 atmosphere. The transformation from a metal hydroxide into a metal nitride could efficiently enhance the electrocatalytic performance for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Interestingly, the incorporation of nickel further boosts the catalytic activity of cobalt nitride. When used as bifunctional electrocatalysts, the obtained nickel-cobalt nitride electrocatalyst shows good stability and superior catalytic performance toward both HER and OER with low overpotentials of 0.29 and 0.18 V, respectively, to achieve a current density of 10 mA cm -2 . The good electrocatalytic performance was also evidenced by the fabrication of an electrolyzer for overall water splitting, which exhibits a high gas generation rate for hydrogen and oxygen with excellent stability during prolonged alkaline water electrolysis. The present work provides an efficient approach to prepare a 3 D interconnected porous nickel-cobalt nitride network with exposed inner active sites for overall water splitting. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Carbon-Nickel oxide nanocomposites: Preparation and charecterisation

    CSIR Research Space (South Africa)

    Tile, N

    2011-07-01

    Full Text Available Nanocomposite materials have wide range of applications in solar energy conversion. In this work, C-NiO nanocomposite coatings are prepared using sol-gel synthesis and deposited on aluminium substrates using a spin coater. The coatings are prepared...

  18. Challenges of sample preparation for cross sectional EBSD analysis of electrodeposited nickel films

    DEFF Research Database (Denmark)

    Alimadadi, Hossein; Pantleon, Karen

    2009-01-01

    . Different procedures for sample preparation including mechanical grinding and polishing, electropolishing and focused ion beam milling have been applied to a nickel film electrodeposited on top of an amorphous Ni-P layer on a Cu-substrate. Reliable EBSD analysis of the whole cross section can be obtained......Thorough microstructure and crystallographic orientation analysis of thin films by means of electron backscatter diffraction requires cross section preparation of the film-substrate compound. During careful preparation, changes of the rather non-stable as-deposited microstructure must be avoided...

  19. Polymer supported nickel complex: Synthesis, structure and catalytic ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 126; Issue 6 ... Regular Articles Volume 126 Issue 6 November 2014 pp 1695-1705 ... In the present investigation, a new synthetic route for a novel recyclable free [3-MOBdMBn-Ni] and polystyrene-anchored [P-3-MOBdMBn-Ni] nickel complexes is presented. The free ...

  20. Preparation of Nickel/Active Carboncatalyst and its Utilization for Benzene Hydrogenation

    Directory of Open Access Journals (Sweden)

    Enggelena Septiawati

    2010-06-01

    Full Text Available The research on the preparation of nickel catalyst impregnated on active carbon by two methods has been carried out. The impregnation of Ni metal was done using nickel(II chloride as a precursor. The impregnated of Ni metal on samples in A method was made in varying of percentage i.e., 0.5, 1.0 and 2.0% (w/w as the weight proportion of Ni to active carbon and NiCl2.6H20. The concentration of Ni that would be impregnated on samples in B method was made close to Ni content of samples in A method determined by atomic adsorption spectrometry. Preparation of nickel/active carbon catalyst with A method was done with dipping the active carbon in the nickel(II chloride solution followed by filtering and then drying at 110 °C for 4 hours, and then calcination by flowing nitrogen and reduction by hydrogen, each at 400 °C at 4 hours. The treatments made on samples in A method was also done on samples in B method, the only difference was evaporating all of precursor solution after dipping active carbon in that precursor solution was done in B method. The characterization includes: iodium adsorption test, determination of nickel content by means of atomic adsorption spectrometry, and acidity by adsorption of ammonia methods. Test of catalyst activity was done by means of hydrogenation of benzene to cyclohexane at 150, 200 and 250 °C, the pressure of 1 atm and the flow rate of hydrogen 6 mL/minute. The products were analyzed by gas chromatographic method. The results show that A method produced a catalyst with relatively low nickel content. However the acidity and ability to convert benzene to cyclohexane were relatively high and it increased as increasing the content of nickel. The temperature of the reaction was achieved at 250 °C which gave the yield on conversion of 25.3678%. The catalyst obtained by B method in the same condition of hydrogenation gave only smaller results.

  1. Super-hydrophobic nickel films with micro-nano hierarchical structure prepared by electrodeposition

    International Nuclear Information System (INIS)

    Hang Tao; Hu Anmin; Ling Huiqin; Li Ming; Mao Dali

    2010-01-01

    Super-hydrophobic nickel films were prepared by a simple and low cost electrodepositing method. The surface morphologies of the films characterized by scanning electronic microscope exhibit hierarchical structure with micro-nanocones array, which can be responsible for their super-hydrophobic characteristic (water contact angle over 150 o ) without chemical modification. The wettability of the film can be varied from super-hydrophobic (water contact angle 154 o ) to relatively hydrophilic (water contact angle 87 o ) by controlling the size of the micro-nanocones. The mechanism of the hydrophobic characteristic of nickel films with this unique structure was illustrated by several models. Such micro-nanostructure and its special wettability are expected to be applied in the practical industry.

  2. [Support and tools for preparing for birth].

    Science.gov (United States)

    Bouychou, Mathilde; Sallez, Hélène; de Brito, Gina; Mouilti, Yamina; Piquée, Nathalie; Boyé, Hélène

    There are a thousand and one ways of preparing to be a parent. Specific support is offered to pregnant women or the couple in order to take the time to prepare for this personal transformation. Haptonomy, sophrology, shiatsu and massage, acupuncture or gestalt therapy are some of the methods helping parents to prepare to welcome their future child with peace of mind. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  3. Structure and properties of nanocrystalline nickel prepared by selective leaching at different temperatures

    Czech Academy of Sciences Publication Activity Database

    Michalcová, A.; Marek, I.; Len, A.; Heczko, Oleg; Drahokoupil, Jan; Vojtěch, D.; Huber, Š.; Nováková, R.

    2017-01-01

    Roč. 89, č. 4 (2017), s. 545-552 ISSN 0033-4545 R&D Projects: GA ČR GBP108/12/G043 Institutional support: RVO:68378271 Keywords : magnetic properties * magnetization * nanocrystals * neutron scattering * nickel * SANS * SSC-2016 * X-ray diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.626, year: 2016

  4. Preparation of high surface area nickel electrodeposit using a liquid crystal template technique

    International Nuclear Information System (INIS)

    Ganesh, V.; Lakshminarayanan, V.

    2004-01-01

    We show in this work that template electrodeposition of nickel at room temperature from a nickel sulphamate bath prepared in a new hexagonal liquid crystalline phase of water-Triton X-100-poly (acrylic acid) results in a highly porous surface. The roughness factor value of about 3620 obtained for this coating is the highest value reported in the literature for any electrodeposited nickel. The scanning electron microscopy (SEM) and scanning tunneling microscopy (STM) pictures show the formation of porous deposit with granular features in between the pores. The single electrode double layer capacitance value measured for the deposit is 338 mF cm -2 , which translates into a specific capacitance of 50 F g -1 without any post-thermal treatment of the electrode, suggesting its utility in super capacitors. Electrochemical studies using cyclic voltammetry (CV), Tafel plots and electrochemical impedance spectroscopy (EIS) and comparison of these results with some existing high surface area Ni catalysts show that the material has potential application as an excellent hydrogen evolving cathode

  5. Development and preparation of thin, supported targets and stripper foils

    International Nuclear Information System (INIS)

    Aaron, W.S.; Petek, M.; Zevenbergen, L.A.; Gibson, J.R.

    1989-01-01

    Usually, it is desirable to prepare thin films that are self-supporting so that any extraneous support materials will not interfere with experimental measurements. However, films with very low areal densities, films other than metals or films covering large areas may require the use of a backing or support. Two classes of supported thin films are being developed by the Isotope Research Materials Laboratory (IRML). Electrodeposition of oxide thin films is a fairly common target preparation technique that is usually performed on backings such as thin metal foils or low atomic number materials like Be and to a lesser extent, C foils. Techniques have been developed by IRML that result in electrodeposition of oxide films up to 500 μg/cm 2 on carbon foils or aluminized mylar. Electrodeposition is a very attractive target fabrication method since it is very efficient in the usage of rare and/or valuable isotopes. The ability to prepare these films on carbon or mylar foils provides a target that has, in most applications, far less interference resulting from the backing. Thin films of carbon, aluminum, boron and titanium are being used as stripper foils in the generation of neutral (H - →H 0 ) particle beams with energies of 50 MeV or greater. Neutralizer foils as large as 25 cm x 25 cm have been prepared from Al and C in thicknesses ranging from 5 to 12 μg/cm 2 that are mounted on thin nickel grids with a transmittance of approximately 90%. Significantly larger foils are currently under development. (orig.)

  6. Simulations on Nickel target preparation and separation of Ni(II)-Cu(II) matrix for production of radioisotope 64Cu

    International Nuclear Information System (INIS)

    Sunarhadijoso Soenarjo; Wira Y Rahman; Sriyono; Triyanto

    2011-01-01

    The simulations on Nickel target preparation and separation of Ni(II)-Cu(II) matrix has been carried out as a preliminary study for production of medical radioisotope Cu-64 based on nuclear reaction of 64 Ni (p,n) 64 Cu. The nickel target preparation was performed by means of electroplating method using acidic solution of nickel chloride - boric acid mixture and basic solution of nickel sulphate - nickel chloride mixture on a silver - surfaced-target holder. The simulated solution of Ni(II) - Cu(II) matrix was considered as the solution of post-proton-irradiated nickel target containing both irradiated nickel and radioactive copper, but in the presented work the proton irradiation of nickel target was omitted, while the radioactive copper was originally obtained from neutron irradiation of CuO target. The separation of radioactive copper from the nickel target matrix was based on anion exchange column chromatography in which the radiocopper was conditioned to form anion complex CuCl 4 2- and retained on the column while the nickel was kept in the form of Ni 2+ cation and eluted off from the column. The retained radioactive copper was then eluted out the column in the condition of dilute HCl changing back the copper anion complex into Cu 2+ cation. It was found that the electroplating result from the acidic solution was more satisfied than that from the basic solution. By conditioning the matrix solution at HCl 6 M, the radioactive copper was found in the forms of Cu 2+ and CuCl 4 2- while the nickel was totally in the form of Ni 2+ . In the condition of HCl 9 M, the radioactive copper was mostly in the form of CuCl 4 2- while the nickel was found as both Ni 2+ and NiCl 4 2- . The best condition of separation was in HCl 8 M in which the radioactive copper was mostly in the form of CuCl 4 2- while the nickel was mostly in the form of Ni 2+ . The retained CuCl 4 2- was then changed back into Cu 2+ cation form and eluted out the column by using HCl 0.05 M. The

  7. CH4 reforming with CO2 for syngas production over nickel catalysts supported on mesoporous nanostructured γ-Al2O3

    International Nuclear Information System (INIS)

    Majidian, Nasrollah; Habibi, Narges; Rezaei, Mehran

    2014-01-01

    Nanostructured γ-Al 2 O 3 with high surface area and mesoporous structure was synthesized by sol-gel method and employed as catalyst support for nickel catalysts in methane reforming with carbon dioxide. The prepared samples were characterized by XRD, BET, TPR, TPH, SEM and TPO techniques. The BET analysis showed a high surface area of 204m 2 g -1 and a narrow pore-size distribution centered at a diameter of 5.5 nm for catalyst support. The results revealed that an increase in nickel loading from 5 to 15 wt% decreased the surface area of catalyst from 182 to 160 m 2 g -1 . In addition, the catalytic results showed an increase in methane conversion with increase in nickel content. TPO analysis revealed that the coke deposition increased with increasing in nickel loading, and the catalyst with 15 wt% of nickel showed the highest degree of carbon formation. SEM and TPH analyses confirmed the formation of whisker type carbon over the spent catalysts. Increasing CO 2 /CH 4 ratio increased the methane conversion. The BET analysis of spent catalysts indicated that the mesoporous structure of catalysts still remained after reaction

  8. Formation, decomposition and cesium adsorption mechanisms of highly alkali-tolerant nickel ferrocyanide prepared by interfacial synthesis

    International Nuclear Information System (INIS)

    Ichikawa, Tsuneki; Yamada, Kazuo; Osako, Masahiro; Haga, Kazuko

    2017-01-01

    Highly alkali-tolerant nickel ferrocyanide was prepared as an adsorbent for preventing the leaching of radioactive cesium from municipal solid waste incinerator fly ash containing large amounts of calcium hydroxide and potassium chloride, which act as an alkaline source and the suppressor for cesium adsorption, respectively. Nickel ferrocyanide prepared by contacting concentrated nickel and ferrocyanide solutions without mixing adsorbed cesium ions in alkaline conditions even the concentration of coexisting potassium ions was more than ten thousand times higher than that of the cesium ions. Large particles of nickel ferrocyanide slowly grew at the interface between the two solutions, which reduced the surface energy of the particles and therefore increased the alkali tolerance. The interfacially-synthesized nickel ferrocyanide was possible to prevent the leaching of radioactive cesium from cement-solidified fly ash for a long period. The mechanisms of the formation, selective cesium adsorption, and alkali-induced decomposition of the nickel ferrocyanide were elucidated. Comparison of the cesium adsorption mechanism with that of the other adsorbents revealed that an adsorbent can selectively adsorb cesium ions without much interference from potassium ions, if the following conditions are fulfilled. 1) The adsorption site is small enough for supplying sufficient electrostatic energy for the dehydration of ions adsorbed. 2) Both the cesium and potassium ions are adsorbed as dehydrated ions. 3) The adsorption site is flexible enough for permitting the penetration of dehydrated ions with the size comparable to that of the site. (author)

  9. Platinum-nickel alloy nanoparticles supported on carbon for 3-pentanone hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Lihua, E-mail: lihuazhu@stu.xmu.edu.cn [School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiang Xi (China); Department of Chemical and Biochemical Engineering, National Engineering Laboratory for Green Productions of Alcohols-Ethers-Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Zheng, Tuo; Yu, Changlin [School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiang Xi (China); Zheng, Jinbao [Department of Chemical and Biochemical Engineering, National Engineering Laboratory for Green Productions of Alcohols-Ethers-Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Tang, Zhenbiao [School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiang Xi (China); Zhang, Nuowei [Department of Chemical and Biochemical Engineering, National Engineering Laboratory for Green Productions of Alcohols-Ethers-Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Shu, Qing [School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiang Xi (China); Chen, Bing H., E-mail: chenbh@xmu.edu.cn [Department of Chemical and Biochemical Engineering, National Engineering Laboratory for Green Productions of Alcohols-Ethers-Esters, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China)

    2017-07-01

    Highlights: • The PtNi/Ni(OH){sub 2}/C catalyst was successfully synthesized at room temperature. • PtNi alloy/C was obtained after PtNi/Ni(OH){sub 2}/C reduced in hydrogen at 300 °C. • Nanostructures of the PtNi catalysts were characterized by numerous techniques. • PtNi alloy/C exhibited high catalytic activity for 3-pentanone hydrogenation. - Abstract: In this work, we prepared the Ni/Ni(OH){sub 2}/C sample at room temperature by hydrazine hydrate reducing method. The galvanic replacement reaction method was applied to deposit platinum on the Ni/Ni(OH){sub 2} nanoparticles, to prepare the PtNi/Ni(OH){sub 2}/C catalyst. The catalyst of platinum-nickel alloy nanoparticles supported on carbon (signed as PtNi/C) was obtained by the thermal treatment of PtNi/Ni(OH){sub 2}/C in flowing hydrogen at 300 °C for 2 h. The size, nanostructure, surface properties, Pt and Ni chemical states of the PtNi/C catalyst were analyzed using powder X-ray diffraction (XRD), transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM), high-angle annular dark-field scanning TEM (HAADF-STEM) and elemental energy dispersive X-ray spectroscopy (EDS) line scanning, X-ray photoelectron spectroscopy (XPS) and high-sensitivity low-energy ion scattering spectroscopy (HS-LEIS) techniques. The as-synthesized PtNi/C catalyst showed enhanced catalytic performance relative to the Ni/Ni(OH){sub 2}/C, Ni/C, Pt/C and PtNi/Ni(OH){sub 2}/C catalysts for 3-pentanone hydrogenation due to electron synergistic effect between Pt and Ni species in the PtNi/C catalyst. The PtNi/C catalyst also had exceling stability, with industrial application value.

  10. Ni/SiO2 Catalyst Prepared with Nickel Nitrate Precursor for Combination of CO2 Reforming and Partial Oxidation of Methane: Characterization and Deactivation Mechanism Investigation

    Directory of Open Access Journals (Sweden)

    Sufang He

    2015-01-01

    Full Text Available The performance of Ni/SiO2 catalyst in the process of combination of CO2 reforming and partial oxidation of methane to produce syngas was studied. The Ni/SiO2 catalysts were prepared by using incipient wetness impregnation method with nickel nitrate as a precursor and characterized by FT-IR, TG-DTA, UV-Raman, XRD, TEM, and H2-TPR. The metal nickel particles with the average size of 37.5 nm were highly dispersed over the catalyst, while the interaction between nickel particles and SiO2 support is relatively weak. The weak NiO-SiO2 interaction disappeared after repeating oxidation-reduction-oxidation in the fluidized bed reactor at 700°C, which resulted in the sintering of metal nickel particles. As a result, a rapid deactivation of the Ni/SiO2 catalysts was observed in 2.5 h reaction on stream.

  11. Preparation and magnetic properties of nano size nickel ferrite particles using hydrothermal method

    Directory of Open Access Journals (Sweden)

    Nejati Kamellia

    2012-03-01

    Full Text Available Abstract Background Nickel ferrite, a kind of soft magnetic materials is one of the most attracting class of materials due to its interesting and important properties and has many technical applications, such as in catalysis, sensors and so on. In this paper the synthesis of NiFe2O4 nanoparticles by the hydrothermal method is reported and the inhibition of surfactant (Glycerol or Sodium dodecyl sulfate on the particles growth is investigated. Methods For investigation of the inhibition effect of surfactant on NiFe2O4 particles growth, the samples were prepared in presence of Glycerol and Sodium dodecyl sulfate. The X-ray powder diffraction (XRD, transmission electron microscopy (TEM, Fourier transform infrared spectroscopy (FT-IR, vibrating sample magnetometer (VSM and inductively coupled plasma atomic emission spectrometer (ICP-AES techniques were used to characterize the samples. Results The results of XRD and ICP-AES show that the products were pure NiFe2O4 and also nanoparticles grow with increasing the temperature, while surfactant prevents the particle growth under the same condition. The average particle size was determined from the Scherrer's equation and TEM micrographs and found to be in the range of 50-60 nm that decreased up to 10-15 nm in presence of surfactant. The FT-IR results show two absorption bands near to 603 and 490 cm-1 for the tetrahedral and octahedral sites respectively. Furthermore, the saturated magnetization and coercivity of NiFe2O4 nanoparticles were in the range of 39.60 emu/g and 15.67 Qe that decreased for samples prepared in presence of surfactant. As well as, the nanoparticles exhibited a superparamagnetic behavior at room temperature. Conclusions Nanosized nickel ferrite particles were synthesized with and without surfactant assisted hydrothermal methods. The results show that with increasing of temperature, the crystallinity of nanoparticles is increased. In the presence of surfactants, the crystallinity of

  12. Preparation of graphene-enhanced nickel-phosphorus composite films by ultrasonic-assisted electroless plating

    Science.gov (United States)

    Yu, Qian; Zhou, Tianfeng; Jiang, Yonggang; Yan, Xing; An, Zhonglie; Wang, Xibin; Zhang, Deyuan; Ono, Takahito

    2018-03-01

    To improve the mechanical properties of nickel-phosphorus (Ni-P) mold material for glass molding, an ultrasonic-assisted electroless plating method is proposed for the synthesis of graphene-enhanced nickel-phosphorus (G-Ni-P) composite films on heat-resistant stainless steel (06Cr25Ni20). Graphene flakes are prepared by an electrochemical exfoliation method. The surface roughness of the as-plated G-Ni-P composite plating is Ra 2.84 μm, which is higher than that of the Ni-P plating deposited using the same method. After annealing at 400 ºC for 2 h, the main phase of the G-Ni-P composite is transformed to crystalline Ni3P with an average grain size of 32.8 nm. The Vickers hardness and Young's modulus of the G-Ni-P composite are increased by 8.0% and 8.2% compared with the values of Ni-P, respectively. The detailed plating process is of great significance for the fabrication of G-Ni-P mold materials with enhanced mechanical properties.

  13. Synthesis and electromagnetic absorption properties of micro-nano nickel powders prepared with liquid phase reduction method

    Directory of Open Access Journals (Sweden)

    Ying Yu

    2016-09-01

    Full Text Available Monodisperse micro-nano nickel powders have been prepared by chemical reduction of aqueous solution NiSO4, NaOH and NaH2PO2, and the influence of pH value and initial concentration of NiSO4 on the size, structure, morphology and microwave absorption properties of nickel powders were investigated. The crystal structure of nickel powders was characterized by X-ray diffraction (XRD. And the morphology of the as-synthesized products was characterized by scanning electron microscopy (SEM and transmission electron microscopy (TEM. The microwave absorption properties of the composite materials were characterized by network analyzer. The result indicates that the growth of nickel powders produced by NiSO4 and NaH2PO2 at alkaline condition deeply relies on pH value and initial concentration of NiSO4 in reaction system. Different sizes of nickel powders with the diameter of 1.5μm and 180nm were produced at the pH value of 10 and initial concentration of NiSO4 at 0.5mol/L. The network analyzer showed definite microwave absorption properties of nickel powders with different sizes in the range of 0.5–18.0GHz.

  14. Preparation of Graphene Oxide Stabilized Nickel Nanoparticles with Thermal Effusivity Properties by Laser Ablation Method

    OpenAIRE

    Sadrolhosseini, Amir Reza; Noor, A. S. M.; Shameli, Kamyar; Kharazmi, Alireza; Huang, N. M.; Mahdi, M. A.

    2013-01-01

    Nickel nanoparticles were dispersed uniformly in a graphene oxide solution, using a laser ablation technique with different ablation times that ranged from 5 to 20 minutes. The results indicate that the nickel nanoparticle sizes inside the graphene oxide decreased, and the volume fraction for the nickel nanoparticles in the graphene oxide increased with an increasing ablation time. Further, using Fourier Transform Infrared Spectroscopy, the nickel nanoparticles in the graphene oxide demonstra...

  15. Preparation and characterization of polystyrene based Nickel molybdate composite membrane electrical–electrochemical properties

    Directory of Open Access Journals (Sweden)

    Urfi Ishrat

    2016-09-01

    Full Text Available The functional properties of the polystyrene based Nickel Molybdate composite membrane prepared by applying 70 MPa pressure are described. The fabricated membrane was characterized by using Fourier Transform Infrared, X-ray diffraction, particle size analyzer and Scanning electron microscopy technique and has been investigated for its functional, diffusive, electrochemical and electrical properties. The impedance data of membrane having capacitive and resistive components are plotted, which show the sequence of semicircles representing an electrical phenomenon due to grain material, grain boundary and interfacial phenomenon. The diffusion of electrolytes was determined by the TMS method revealing dependence of membrane potential on the charge on the membrane matrix, charge and size of permeating ions. The membrane determined the activity of cations with good accuracy in the higher concentration range and shows a great selectivity for K+. Other electrochemical properties like transport number have been discussed its selectivity.

  16. Preparation, characterization and catalytic properties of nickel aluminate nanoparticles: A comparison between conventional and microwave method

    Directory of Open Access Journals (Sweden)

    C. Ragupathi

    2017-01-01

    Full Text Available In the present work, synthesis of nickel aluminate using Opuntia dilenii haw as plant extract by a microwave combustion method (MCM and its comparison with the conventional combustion method (CCM is investigated. O. dilenii haw plant extract simplifies the process, provides an alternative process for a simple and an economical synthesis. The absence of surfactant has led to a simple, cheap and fast method of synthesis of NiAl2O4 nanoparticles. The as-synthesized NiAl2O4 nanoparticles were characterized by X-ray diffraction (XRD studies, Fourier transform infrared spectroscopy (FT-IR studies, high resolution scanning electron microscopy (HR-SEM, energy dispersive X-ray analysis (EDX, high resolution transmission electron microscopy (HR-TEM, diffuses reflectance spectroscopy (DRS, and Brunauer Emmett Teller (BET surface area analysis. The XRD results confirmed the formation of the cubic phase NiAl2O4. The formation of pure nickel aluminate phase was confirmed by FT-IR. The formation of NiAl2O4 nanoparticles was confirmed by HR-SEM and HR-TEM and their possible formation mechanisms were also proposed. MCM could produce NiAl2O4 with uniform size and well-defined shape with crystallinity. The optical property was determined by DRS. NiAl2O4 prepared by the microwave combustion method was found to possess a higher surface area, lower crystallite size than the NiAl2O4 nanoparticles prepared by the conventional combustion method, which in turn has led to the improved performance toward the selective oxidation of benzyl alcohol to benzaldehyde.

  17. Glow Discharge Plasma-Assisted Preparation of Nickel-Based Catalyst for Carbon Dioxide Reforming of Methane

    Science.gov (United States)

    Guo, Fang; Chu, Wei; Xu, Jun-qiang; Zhong, Lin

    2008-10-01

    A plasma-assisted method was employed to prepare Ni/γ-Al2O3 catalyst for carbon dioxide reforming of methane reaction. The novel catalyst possessed higher activity and better coke-suppression performance than those of the conventional calcination catalyst. To achieve the same CH4 conversion, the conventional catalyst needed higher reaction temperature, about 50°C higher than that of the N2 plasma-treated catalyst. After the evaluation test, the deactivation rate of the novel catalyst was 1.7%, compared with 15.2% for the conventional catalyst. Different from the characterization results of the calcined catalyst, a smaller average pore diameter and a higher specific surface area were obtained for the plasma-treated catalyst. The variations of the reduction peak temperatures and areas indicated that the catalyst reducibility was promoted by plasma assistance. The dispersion of nickel was also remarkably improved, which was helpful for controlling the ensemble size of metal atoms on the catalyst surface. The modification effect of plasma-assisted preparation on the surface property of alumina supported catalyst was speculated to account for the concentration increase of absorbed CO2. An enhancement of CO2 adsorption was propitious to the inhibition of carbon formation. The coke amount deposited on plasma treated catalyst was much smaller than that on the conventional catalyst.

  18. Preparation of nickel(II)-azo dye films and their optical properties for write-once blu-ray recording

    Science.gov (United States)

    Chen, Zhimin; Wu, Yiqun; He, Chunying; Wang, Bin; Miao, Shoulei; Duan, Wubiao; Gu, Donghong; Gan, Fuxi

    A nickel(II)-azo dye was synthesized in order to obtain a suitable optical recording medium for write-once blu-ray recording with low-to-high signal polarity. Smooth thin film of the nickel(II)-azo dye was prepared by spin-coating method. Absorption, reflectance spectra and optical constants (complex refractive indices N=n+ik) of the thin film were investigated in the wavelength region of 300-700 nm. To demonstrate the physical basis of low-to-high polarity, the relationships between the absorption, reflectivity and optical constants for the nickel(II)-azo dye in spin-coated films were discussed. It is found that the thin film has a strong absorption band in the wavelength region of 370-500 nm and a strong absorbance at 405 nm. The reflectance spectra show that a low reflectivity of the unrecorded thin film at 405 nm can be obtained. The thin film of the nickel(II)-azo dye gives a relatively low n value of 1.36 and a relatively high k value of 0.51 at 405 nm. In addition, in order to examine its possible use as a blu-ray recording medium, the spin-coated film of the nickel(II)-azo dye was studied by a static optical recording testing system. The results demonstrate that high reflectivity contrast (85%) with low-to-high polarity can be obtained at an optimum laser writing power and pulse width using the nickel(II)-azo dye thin film as the recording layer. Moreover, the recording marks on the film are clear, circular, regular, and their size is as small as 200 nm or even less. These results indicate that the nickel(II)-azo dye is promising for applications in high-performance write-once blu-ray recording systems at 405 nm.

  19. The target preparation of 232Th plated on the nickel with copper as substrate and 230Pa generation

    International Nuclear Information System (INIS)

    Shen Hua; Geng Junxia; Gao Size; Zhang Guoxin; Zhang Lan; Li Wenxin; Li Qingnuan; Wu Guozhong

    2014-01-01

    The electrochemical parameters on nickel plating on the copper have been studied using aqueous electroplating technique. And thorium is plated on the nickel flake using molecular plating technique. The better experimental parameters are obtained. According to these optimized parameters, the 232 Th target which is suitable for Cyclone-30 accelerator is prepared. The proton beam with energy of 21 MeV bombed the 232 Th target (total beam time 20 μAh). The results showed that the better range of plating current density of nickel plated on copper is l.30∼1.68 A/dm 2 . The thickness of nickel plating layer can reach more than 10 μm. The current density is 3∼5 mA/cm 2 , and the thickness of plated thorium layer is up to micrometer scale. The binding force of as-prepared 232 Th target is very well. There is 230 Pa appeared after the target is bombed by the proton beam. (authors)

  20. Deposition efficiency in the preparation of ozone-producing nickel and antimony doped tin oxide anodes

    Directory of Open Access Journals (Sweden)

    Staffan Sandin

    2017-03-01

    Full Text Available The influence of precursor salts in the synthesis of nickel and antimony doped tin oxide (NATO electrodes using thermal decomposition from dissolved chloride salts was investigated. The salts investigated were SnCl4×5H2O, SnCl2×2H2O, SbCl3 and NiCl2×6H2O. It was shown that the use of SnCl4×5H20 in the preparation process leads to a tin loss of more than 85 %. The loss of Sb can be as high as 90 % while no indications of Ni loss was observed. As a consequence, the concentration of Ni in the NATO coating will be much higher than in the precursor solution. This high and uncontrolled loss of precursors during the preparation process will lead to an unpredictable composition in the NATO coating and will have negative economic and environmental effects. It was found that using SnCl2×2H20 instead of SnCl4×5H2O can reduce the tin loss to less than 50 %. This tin loss occurs at higher temperatures than when using SnCl4×5H2O where the tin loss occurs from 56 – 147 °C causing the composition to change both during the drying (80 – 110 °C and calcination (460 -550 °C steps of the preparation process. Electrodes coated with NATO based on the two different tin salts were investigated for morphology, composition, structure, and ozone electrocatalytic properties.

  1. Effect study of the support in nickel and cobalt catalysts for obtaining hydrogen from ethanol steam reforming

    International Nuclear Information System (INIS)

    Silva, Sirlane Gomes da

    2013-01-01

    A range of oxide-supported metal catalysts have been investigated for the steam reforming of ethanol for the production of hydrogen and subsequent application in fuel cells. The catalysts were synthesized by the co-precipitation and internal gelification methods using cobalt and nickel as active metals supported on aluminum, zirconium, lanthanum and cerium oxides. After prepared and calcined at 550 Cº the solids were fully characterized by different techniques such as X-rays diffraction(DRX), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy, nitrogen adsorption (B.E.T), temperature-programmed reduction in H2 (TPR-H2) and thermogravimetric analysis. The catalytic tests were performed in a monolithic quartz reactor and submitted to different thermodynamic conditions of steam reforming of ethanol at temperatures varying from 500º C to 800 ºC. The product gas streams from the reactor were analyzed by an on-line gas chromatograph. The cobalt/nickel catalyst supported on a ceria-lanthania mixture (Co 10% / Ni 5% - CeO 2 La 2 O 3 ) showed good catalytic performance in hydrogen selectivity reaching a concentration greater than 65%, when compared to other catalytic systems such as: Co 10% / Ni5% - CeO 2 ; Co 10% / Ni 5% - CeO 2 ZrO 2 ; Co 10% / Ni 5% - ZrO 2 ; Co 10% / Ni 5% - La 2 O 3 ; Co 10% / Ni 5% - CeO 2 La 2 O 3 /K 2% ; Co 10 % / Ni 5% - CeO 2 La 2 O 3 / Na 2% ; Ni 10% / Co 5% - CeO 2 La 2 O 3 ; Co-Al 2 O 3 e Co-Al 2 O 3 CeO 2 . (author)

  2. Evaluation of sample preparation methods and optimization of nickel determination in vegetable tissues

    Directory of Open Access Journals (Sweden)

    Rodrigo Fernando dos Santos Salazar

    2011-02-01

    Full Text Available Nickel, although essential to plants, may be toxic to plants and animals. It is mainly assimilated by food ingestion. However, information about the average levels of elements (including Ni in edible vegetables from different regions is still scarce in Brazil. The objectives of this study were to: (a evaluate and optimize a method for preparation of vegetable tissue samples for Ni determination; (b optimize the analytical procedures for determination by Flame Atomic Absorption Spectrometry (FAAS and by Electrothermal Atomic Absorption (ETAAS in vegetable samples and (c determine the Ni concentration in vegetables consumed in the cities of Lorena and Taubaté in the Vale do Paraíba, State of São Paulo, Brazil. By means of the analytical technique for determination by ETAAS or FAAS, the results were validated by the test of analyte addition and recovery. The most viable method tested for quantification of this element was HClO4-HNO3 wet digestion. All samples but carrot tissue collected in Lorena contained Ni levels above the permitted by the Brazilian Ministry of Health. The most disturbing results, requiring more detailed studies, were the Ni concentrations measured in carrot samples from Taubaté, where levels were five times higher than permitted by Brazilian regulations.

  3. Preparation and characterization of Nickel-and cobalt-doped magnetites

    Directory of Open Access Journals (Sweden)

    Lelis Maria de Fátima Fontes

    2003-01-01

    Full Text Available Nickel- and cobalt-doped magnetites were prepared by a co-precipitation method and studied in some detail, in an effort to identify some effects of the doping cations on the magnetic, crystallographic and morphological properties of the resulting spinel. The synthetic samples were characterized by conventional chemical analysis, powder X-ray diffractometry, Mössbauer spectroscopy, saturation magnetization and scanning electron microscopy. From chemical analysis, the continuous increase of Ni2+ or Co2+ is accompanied by a simultaneous decrease of the Fe2+ contents, in the spinel structure. The magnetization values also decrease continuously with increasing doping cation contents. Mössbauer parameters are characteristic of substituted magnetites and indicate the presence of a single phase only. Based on the inverted intensities of the lines 1 (leftmost, on the negative Doppler velocity scale and 2 of Mössbauer spectra of doped samples, relatively to the pure magnetite, it was assumed that the isomorphical substitution occurs preferentially on octahedral coordination sites of the spinel structure. The coercive field of these ferrites decrease steadily with Ni2+ but increases with Co2+ contents, reaching a maximum at x = 0.38, in the general formula Co xFe3-xO4 .

  4. Catalytic Hydrolysis of Ammonia Borane by Cobalt Nickel Nanoparticles Supported on Reduced Graphene Oxide for Hydrogen Generation

    Directory of Open Access Journals (Sweden)

    Yuwen Yang

    2014-01-01

    Full Text Available Well dispersed magnetically recyclable bimetallic CoNi nanoparticles (NPs supported on the reduced graphene oxide (RGO were synthesized by one-step in situ coreduction of aqueous solution of cobalt(II chloride, nickel (II chloride, and graphite oxide (GO with ammonia borane (AB as the reducing agent under ambient condition. The CoNi/RGO NPs exhibits excellent catalytic activity with a total turnover frequency (TOF value of 19.54 mol H2 mol catalyst−1 min−1 and a low activation energy value of 39.89 kJ mol−1 at room temperature. Additionally, the RGO supported CoNi NPs exhibit much higher catalytic activity than the monometallic and RGO-free CoNi counterparts. Moreover, the as-prepared catalysts exert satisfying durable stability and magnetically recyclability for the hydrolytic dehydrogenation of AB, which make the practical reusing application of the catalysts more convenient. The usage of the low-cost, easy-getting catalyst to realize the production of hydrogen under mild condition gives more confidence for the application of ammonia borane as a hydrogen storage material. Hence, this general method indicates that AB can be used as both a potential hydrogen storage material and an efficient reducing agent, and can be easily extended to facile preparation of other RGO-based metallic systems.

  5. Adsorption of heavy metal ion from aqueous solution by nickel oxide nano catalyst prepared by different methods

    Directory of Open Access Journals (Sweden)

    Amira M. Mahmoud

    2015-03-01

    Full Text Available Environmental pollution by heavy metal is arising as the most endangering tasks to both water sources and atmosphere quality today. The treatment of heavy metals is of special concern due to their recalcitrance and persistence in the environment. To limit the spread of the heavy metals within water sources, nickel oxide nanoparticles adsorbents were synthesized and characterized with the aim of removal of one of the aggressive heavy elements, namely; lead ions. Nano nickel oxide adsorbents were prepared using NaOH and oxalic acid dissolved in ethanol as precursors. The results indicated that adsorption capacity of Pb(II ion by NiO-org catalyst is favored than that prepared using NaOH as a precipitant. Nickel oxide nanoparticles prepared by the two methods were characterized structurally and chemically through XRD, DTA, TGA, BET and FT-IR. Affinity and efficiency sorption parameters of the solid nano NiO particles, such as; contact time, initial concentration of lead ions and the dosage of NiO nano catalyst and competitive adsorption behaviors were studied. The results showed that the first-order reaction law fit the reduction of lead ion, also showed good linear relationship with a correlation coefficient (R2 larger than 0.9.

  6. Microstructure and deformation behavior of nickel based superalloy Inconel 740 prepared by electron beam smelting

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Yi, E-mail: tanyi@dlut.edu.cn; You, Xiaogang; You, Qifan; Li, Jiayan; Shi, Shuang; Li, Pengting

    2016-04-15

    activation energy Q. The EBS technology shows encouraging potential in preparation of nickel-based superalloys. Morphologies of γ′ precipitates and Vickers hardness as well as hot compression curves for electron beam smelting 740 superalloy. - Highlights: • Electron beam smelting, a novel method, was used to prepare the Inconel 740 superalloy. • The average size of the γ′ precipitates after aging treatment is < 30 nm. • The shearing mode generates a stronger strengthening effect than the traditional 740. • At low Zener-Hollomon parameter, the EBS 740 shows higher flow stress than 740H.

  7. Preparation and characterization of nickel-spiked freshwater sediments for toxicity tests: toward more environmentally realistic nickel partitioning.

    Science.gov (United States)

    Brumbaugh, William G; Besser, John M; Ingersoll, Christopher G; May, Thomas W; Ivey, Chris D; Schlekat, Christian E; Garman, Emily Rogevich

    2013-11-01

    Two spiking methods were compared and nickel (Ni) partitioning was evaluated during a series of toxicity tests with 8 different freshwater sediments having a range of physicochemical characteristics. A 2-step spiking approach with immediate pH adjustment by addition of NaOH at a 2:1 molar ratio to the spiked Ni was effective in producing consistent pH and other chemical characteristics across a range of Ni spiking levels. When Ni was spiked into sediment having a high acid-volatile sulfide and organic matter content, a total equilibration period of at least 10 wk was needed to stabilize Ni partitioning. However, highest spiking levels evidently exceeded sediment binding capacities; therefore, a 7-d equilibration in toxicity test chambers and 8 volume-additions/d of aerobic overlying water were used to avoid unrealistic Ni partitioning during toxicity testing. The 7-d pretest equilibration allowed excess spiked Ni and other ions from pH adjustment to diffuse from sediment porewater and promoted development of an environmentally relevant, 0.5- to 1-cm oxic/suboxic sediment layer in the test chambers. Among the 8 different spiked sediments, the logarithm of sediment/porewater distribution coefficient values (log Kd ) for Ni during the toxicity tests ranged from 3.5 to 4.5. These Kd values closely match the range of values reported for various field Ni-contaminated sediments, indicating that testing conditions with our spiked sediments were environmentally realistic. © 2013 SETAC.

  8. Preparation of Graphene Oxide Stabilized Nickel Nanoparticles with Thermal Effusivity Properties by Laser Ablation Method

    Directory of Open Access Journals (Sweden)

    Amir Reza Sadrolhosseini

    2013-01-01

    Full Text Available Nickel nanoparticles were dispersed uniformly in a graphene oxide solution, using a laser ablation technique with different ablation times that ranged from 5 to 20 minutes. The results indicate that the nickel nanoparticle sizes inside the graphene oxide decreased, and the volume fraction for the nickel nanoparticles in the graphene oxide increased with an increasing ablation time. Further, using Fourier Transform Infrared Spectroscopy, the nickel nanoparticles in the graphene oxide demonstrate greater stability from possible agglomeration when the nanoparticle was capped with oxygen from the carboxyl group of the graphene oxide. The thermal effusivity of the graphene oxide and nickel nanoparticle graphene oxide composite was measured using a photoacoustic technique. The concentration of graphene oxide shifted from 0.05 mg/L to 2 mg/L, and the thermal effusivity increased from 0.153 W·s1/2·cm−2·K−1 to 0.326 W·s1/2·cm−2·K−1. In addition, the thermal effusivity of the nickel nanoparticles graphene oxide composite increased with an increase in the volume fraction of nickel nanoparticles from 0.1612 W·s1/2·cm−2·K−1 to 0.228 W·s1/2·cm−2·K−1.

  9. Hierarchical copper-decorated nickel nanocatalysts supported on La2O3 for low-temperature steam reforming of ethanol.

    Science.gov (United States)

    Liu, Jyong-Yue; Su, Wei-Nien; Rick, John; Yang, Sheng-Chiang; Cheng, Ju-Hsiang; Pan, Chun-Jern; Lee, Jyh-Fu; Hwang, Bing-Joe

    2014-02-01

    Copper/nickel nanocatalysts with a unique morphology were prepared by thermal reduction of a perovskite LaNix Cu1-x O3 precursor (x=1, 0.9, and 0.7). During thermal reduction, copper was first reduced and reacted with lanthanum to form metastable Cu5 La and Cu13 La. When the thermal reduction temperature was increased, the perovskite decomposed to Ni and La2 O3 , CuLa alloys disappeared, and Cu deposits on Ni nanoparticles were generated, thereby forming Cu/Ni nanocatalysts with hierarchical structures. Nanosized nickel, decorated with copper and supported on La2 O3 , could be produced at 520-550 °C. The steam reforming of ethanol was used as a model reaction to demonstrate the catalytic capability of the materials formed. The hierarchical structure of the Cu/Ni/La2 O3 catalysts confers synergetic effects that greatly favor the dehydrogenation of ethanol and which break the C-C bond to produce a higher yield of hydrogen at a low reaction temperature, whereas La2 O3 provides the required stability during the reaction. The reaction at 290 °C achieved almost 100 % conversion with a hydrogen yield reaching 2.21 molH2  mol(-1) EtOH thus indicating that this special structural feature can achieve high activity for the SRE at low temperatures. The proposed synthesis of nanocatalysts appears to be a good way to generate oxide-supported hierarchically structured nanoparticles that can also be applied to other reactions catalyzed by a heterogeneous metal oxide system. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Influence of preparation conditions of hollow silica–nickel composite spheres on their catalytic activity for hydrolytic dehydrogenation of ammonia borane

    Energy Technology Data Exchange (ETDEWEB)

    Umegaki, Tetsuo, E-mail: umegaki.tetsuo@nihon-u.ac.jp [Department of Materials and Applied Chemistry, College of Science and Engineering, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-Ku, Tokyo 101-8308 (Japan); Seki, Ayano [Department of Materials and Applied Chemistry, College of Science and Engineering, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-Ku, Tokyo 101-8308 (Japan); Xu, Qiang [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Kojima, Yoshiyuki [Department of Materials and Applied Chemistry, College of Science and Engineering, Nihon University, 1-8-14, Kanda-Surugadai, Chiyoda-Ku, Tokyo 101-8308 (Japan)

    2014-03-05

    Highlights: • We study influence of preparation conditions on activity of hollow silica–nickel composite spheres. • The activity for hydrolytic dehydrogenation of NH{sub 3}BH{sub 3} increases with increase of Si+Ni content. • The particle size distribution affects the activity and reducibility of active nickel species. • The amount of PS residue in the hollow spheres decreases by treatment of as-prepared sample in toluene. -- Abstract: In this paper, we investigated influence of preparation conditions of hollow silica–nickel composite spheres on their morphology and catalytic activity for hydrolytic dehydrogenation of ammonia borane. In the preparation method of this study, when silica–nickel composite shells were coated on polystyrene templates by the sol–gel method using L(+)-arginine as the promoter for the reaction to form silica–nickel composite shell, the polystyrene templates were dissolved subsequently, even synchronously, in the same medium to form hollow spheres. The as-prepared silica–nickel composite spheres were characterized by transmission electron microscopy and scanning electron microscopy. The effects of Si+Ni content on the morphology were systematically evaluated. All the as-prepared hollow silica–nickel composite spheres have the similar morphology as identified by SEM and TEM measurement. Homogeneity of the hollow silica–nickel composite spheres increases with the increase in the Si+Ni content as shown by the laser diffraction particle size analysis. The catalytic activities of the hollow silica–nickel composite spheres for hydrolytic dehydrogenation of ammonia borane prepared with different Si+Ni contents were compared. The catalytic activity for the hydrogen evolution in the presence of the hollow spheres increases with the increase of Si+Ni content. The results of FTIR spectra of the hollow silica–nickel composite spheres indicate that a certain amount of residual PS templates exists in hollow silica–nickel

  11. Preparation of ordered mesoporous nickel oxide film electrodes via lyotropic liquid crystal templated electrodeposition route

    International Nuclear Information System (INIS)

    Zhao Dandan; Xu Maowen; Zhou Wenjia; Zhang Jin; Li Hulin

    2008-01-01

    A novel electrochemical route to fabricate ordered mesoporous metal oxide film electrodes has been investigated with particular reference to nickel oxide. Ordered mesoporous nickel oxide films are successfully synthesized by templated electrodeposition of H I -e nickel hydroxide and followed by heat-treatment in air at various temperatures. The films are characterized physically by thermogravimetry (TG), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The applicability of this film as inexpensive and high-performance supercapacitor electrode material is demonstrated by the electrochemical characterization using cyclic voltammetry (CV) and chronopotentiometry technique. The specific capacitance of the nickel oxide film depends on the annealing temperature, showing a maximum value of 590 F g -1 when the as-deposited film is heat-treated at 250 deg. C for 1.5 h

  12. The effect of titanium nickel nitride decorated carbon nanotubes-reduced graphene oxide hybrid support for methanol oxidation

    Science.gov (United States)

    Liu, Gen; Pan, Zhanchang; Li, Wuyi; Yu, Ke; Xia, Guowei; Zhao, Qixiang; Shi, Shikun; Hu, Guanghui; Xiao, Chumin; Wei, Zhigang

    2017-07-01

    Titanium nickel nitride (TiNiN) decorated three-dimensional (3D) carbon nanotubes-reduced graphene oxide (CNT-rGO), a fancy 3D platinum (Pt)-based catalyst hybrid support, is prepared by a solvothermal process followed by a nitriding process, which is tested as anodic catalyst support for the methanol oxidation reaction (MOR). The structure, morphology and composition of the synthesized TiNiN/CNT-rGO exhibits a uniform particle dispersion with high purity and interpenetrating 3D network structure. Notably, Pt/TiNiN/CNT-rGO catalyst exhibits significantly improved catalytic activity and durability for methanol oxidation in comparison with Pt/CNT-rGO and conventional Pt/C (JM). The outstanding electrochemical performance was attributed to structure and properties. That is, the 3D CNT-rGO provided a fast transport network for charge-transfer and mass-transfer as well as TiNiN NPs with good synergistic effect and the strong electronic coupling between different domains in TiNiN/CNT-rGO, thus the catalytic activity of the novel catalyst is greatly improved. These results evidences 3D TiNiN/CNT-rGO as a promising catalyst support for a wide range of applications in fuel cells.

  13. Scalable Preparation of Ternary Hierarchical Silicon Oxide-Nickel-Graphite Composites for Lithium-Ion Batteries.

    Science.gov (United States)

    Wang, Jing; Bao, Wurigumula; Ma, Lu; Tan, Guoqiang; Su, Yuefeng; Chen, Shi; Wu, Feng; Lu, Jun; Amine, Khalil

    2015-12-07

    Silicon monoxide is a promising anode candidate because of its high theoretical capacity and good cycle performance. To solve the problems associated with this material, including large volume changes during charge-discharge processes, we report a ternary hierarchical silicon oxide-nickel-graphite composite prepared by a facile two-step ball-milling method. The composite consists of nano-Si dispersed silicon oxides embedded in nano-Ni/graphite matrices (Si@SiOx /Ni/graphite). In the composite, crystalline nano-Si particles are generated by the mechanochemical reduction of SiO by ball milling with Ni. These nano-Si dispersed oxides have abundant electrochemical activity and can provide high Li-ion storage capacity. Furthermore, the milled nano-Ni/graphite matrices stick well to active materials and interconnect to form a crosslinked framework, which functions as an electrical highway and a mechanical backbone so that all silicon oxide particles become electrochemically active. Owing to these advanced structural and electrochemical characteristics, the composite enhances the utilization efficiency of SiO, accommodates its large volume expansion upon cycling, and has good ionic and electronic conductivity. The composite electrodes thus exhibit substantial improvements in electrochemical performance. This ternary hierarchical Si@SiOx /Ni/graphite composite is a promising candidate anode material for high-energy lithium-ion batteries. Additionally, the mechanochemical ball-milling method is low cost and easy to reproduce, indicating potential for the commercial production of the composite materials. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Evaluation of dentinal defects during root canal preparation using thermomechanically processed nickel-titanium files.

    Science.gov (United States)

    Kesim, Bertan; Sagsen, Burak; Aslan, Tugrul

    2017-01-01

    The aim of this study was to compare the incidence of root cracks after root canal instrumentation with thermomechanically processed nickel-titanium (Ni-Ti) files with different instrumentation kinematics. A total of 150 extracted mandibular premolars with mature apices and straight root canals were divided into five groups and used in this study. In Group 1, 30 teeth were prepared using hand K-files and assigned to control group, Group 2 was instrumented using K3XF Rotary files (SybronEndo, Glendora, CA, USA) with continuous rotary motion. The teeth in Group 3 were instrumented by ProTaper Next (Dentsply Maillefer, Ballaigues, Switzerland) rotary files which make asymmetric rotary motion, In Group 4, teeth were instrumented by RECIPROC (VDW, Munich, Germany) with reciprocation motion and in Group 5, teeth were instrumented by Twisted File (TF) Adaptive (SybronEndo, Orange, CA, USA) files that use combination of continuous rotation and reciprocation motion ( n = 30/per group). All the roots were horizontally sectioned 3, 6, and 9 mm from the apex with a low speed saw under water cooling. Then, the slices were examined through a stereomicroscope to determine the presence of dentinal microcracks. For the apical (3-mm) and coronal (9-mm) sections, the ProTaper Next and TF Adaptive produced significantly more cracks than the hand files, RECIPROC, and K3XF ( P 0.05). Within the limitations of this in vitro study, all thermal-treated Ni-Ti instruments and hand files caused microcracks in root canal dentin.

  15. Tuning crystal phase of NiS{sub x} through electro-oxidized nickel foam: A novel route for preparing efficient electrocatalysts for oxygen evolution reaction

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiao; Shang, Xiao [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Rao, Yi [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580, PR China (China); Dong, Bin, E-mail: dongbin@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580, PR China (China); Han, Guan-Qun [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580, PR China (China); Hu, Wen-Hui; Liu, Yan-Ru; Yan, Kai-Li; Chi, Jing-Qi; Chai, Yong-Ming [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Liu, Chen-Guang, E-mail: cgliu@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China)

    2017-02-28

    Highlights: • Electro-oxidized nickel foam as a support has been used to prepare NiS{sub x} phases. • Ni(OH){sub 2} layer on electro-oxidized NF is responsible for the growth of β-NiS. • NiS{sub x}/NF(Ox) composed of β-NiS and Ni{sub 3}S{sub 2} has enhanced electrocatalytic activity. • The growth mechanisms of mixed NiS{sub x} phases of NiS{sub x}/NF(Ox) have been discussed. - Abstract: A facile solvothermal sulfurization using electro-oxidized nickel foam (NF(Ox)) as support has been applied to prepare NiS{sub x}/NF(Ox) electrocatalyst with highly efficient activity for oxygen evolution reaction (OER). XRD patterns confirm the composition of NiS{sub x}/NF(Ox): two kinds of crystal phase including β-NiS and Ni{sub 3}S{sub 2}. While using bare NF as support under identical conditions, only Ni{sub 3}S{sub 2} phase can be detected. SEM images reveal two kinds of morphologies of NiS{sub x}/NF(Ox) including pyramids structure of β-NiS and nanorod-like structure of Ni{sub 3}S{sub 2}, which implies the tuning effect of electro-pretreatment of NF on the selective preparation of NiS{sub x} crystal phase. It can be speculated that Ni(OH){sub 2} layer derived from electro-oxidized NF is responsible for the growth of β-NiS while metallic Ni is transformed into Ni{sub 2}S{sub 3} during sulfurization. Electrochemical measurements for OER indicate the enhanced electrocatalytic activity of NiS{sub x}/NF(Ox) with a small overpotential of 72 mV to reach 10 mA cm{sup −2} compared with Ni{sub 3}S{sub 2}/NF, which may be ascribed to the improved electron-transfer kinetics relating to the unique atomic configurations and crystalline structures of β-NiS. The electro-oxidation pretreatment of nickel foam provides a simple and convenient method by tuning different NiS{sub x} crystal phases for preparing excellent OER eletrocatalysts.

  16. The TEXTOR helium self-pumping experiment: Design, plans, and supporting ion-beam data on helium retention in nickel

    International Nuclear Information System (INIS)

    Brooks, J.N.; Krauss, A.; Mattas, R.F.; Smith, D.L.; Nygren, R.E.; Doyle, B.L.; McGrath, R.T.; Walsh, D.; Dippel, K.H.; Finken, K.H.

    1990-01-01

    A proof-of-principle experiment to demonstrate helium self-pumping in a tokamak is being undertaken in TEXTOR. The experiment will use a helium self-pumping module installed in a modified ALT-I limiter head. The module consists of two, ≅ 25x25 cm 2 heated nickel alloy trapping plates, a nickel deposition filament array, and associated diagnostics. Between plasma shots a coating of ≅ 50A nickel will be deposited on the two trapping plates. During a shot helium and hydrogen ions will impinge on the plates through a ≅ 3 cm wide entrance slot. The helium removal capability, due to trapping in the nickel, will be assessed for a variety of plasma conditions. In support of the tokamak experiment, the trapping of helium over a range of ion fluences and surface temperatures, and detrapping during subsequent exposure to hydrogen, were measured in ion beam experiments using evaporated nickel surfaces similar to that expected in TEXTOR. Also, the retention of H and He after exposure of a nickel surface to mixed He/H plasmas has been measured. The results appear favorable, showing high helium trapping (≅ 10-50% He/Ni) and little or no detrapping by hydrogen. The TEXTOR experiment is planned to begin in 1991. (orig.)

  17. Preparation and Characterization of Mesoporous Nickel derived from Liquid crystalline Template and Evaluation of its Electro catalytic activity towards Methanol Oxidation

    Science.gov (United States)

    Mohanapriya, S.; Renuka devi, R.; Raj, V.

    2018-02-01

    Mesoporous Nickel has been prepared by electrodeposition using non-ionic surfactant based liquid crystalline template under optimized processing conditions. Physico-chemical properties of mesoporous nickel is systematically characterized through XRD, SEM and AFM analyses. Comparison of electrocatalytic activity of mesoporous nickel with smooth nickel was interrogated using cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) analyses. Distinctly enhanced electrocatalytic activity with improved surface poisoning resistance related to mesoporous nickel electrode towards methanol oxidation stems from unique mesoporous morphology. This mesoporous morphology with high surface to volume ratio is highly beneficial to promote active catalytic centers to offer readily accessible Pt catalytic sites for MOR, through facilitating mass and electron transports.

  18. Long term ground support with stainless steel and nickel alloy rock bolts

    International Nuclear Information System (INIS)

    Shaffer, T.F.; Revie, R.W.; Mandal, A.

    1994-01-01

    Stainless steel and nickel alloy Swellex rock bolts have been developed to provide long-term ground support in corrosive environments or in underground openings that are inaccessible for periodic reconditioning. Laboratory and underground testing has shown that the mechanical properties of stainless steel Swellex rock bolts am adequate for long term service. The corrosivity of underground sites may vary considerably and no one grade of stainless steel will provide adequate corrosion resistance economically for permanent service at all sites. Six stainless steels and two nickel alloys have been evaluated and used to manufacture Swellex. These alloys can be used to manufacture all types of rock bolts including mechanically anchored bolts. The selection of the lowest-cost corrosion-resistant alloy suitable for the lifetime objective at a given site may be problematic. Therefore, a mine corrosivity assessment procedure, in which the performance of several candidate materials for permanent service at a specific site can be determined quickly and economically, is being developed and will be available in 1995

  19. Does airborne nickel exposure induce nickel sensitization?

    Science.gov (United States)

    Mann, Eugen; Ranft, Ulrich; Eberwein, Georg; Gladtke, Dieter; Sugiri, Dorothee; Behrendt, Heidrun; Ring, Johannes; Schäfer, Torsten; Begerow, Jutta; Wittsiepe, Jürgen; Krämer, Ursula; Wilhelm, Michael

    2010-06-01

    Nickel is one of the most prevalent causes of contact allergy in the general population. This study focuses on human exposure to airborne nickel and its potential to induce allergic sensitization. The study group consisted of 309 children at school-starter age living in the West of Germany in the vicinity of two industrial sources and in a rural town without nearby point sources of nickel. An exposure assessment of nickel in ambient air was available for children in the Ruhr district using routinely monitored ambient air quality data and dispersion modelling. Internal nickel exposure was assessed by nickel concentrations in morning urine samples of the children. The observed nickel sensitization prevalence rates varied between 12.6% and 30.7%. Statistically significant associations were showed between exposure to nickel in ambient air and urinary nickel concentration as well as between urinary nickel concentration and nickel sensitization. Furthermore, an elevated prevalence of nickel sensitization was associated with exposure to increased nickel concentrations in ambient air. The observed associations support the assumption that inhaled nickel in ambient air might be a risk factor for nickel sensitization; further studies in larger collectives are necessary.

  20. Preparation, Characterization and Catalytic Activity of Nickel Molybdate (NiMoO4 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Hicham Oudghiri-Hassani

    2018-01-01

    Full Text Available Nickel molybdate (NiMoO4 nanoparticles were synthesized via calcination of an oxalate complex in static air at 500 °C. The oxalate complex was analyzed by thermal gravimetric analysis (TGA and Fourier transform infrared spectroscopy (FTIR. The as-synthesized nickel molybdate was characterized by Brunauer–Emmett–Teller technique (BET, X-ray diffraction (XRD, and transmission electron microscopy (TEM and its catalytic efficiency was tested in the reduction reaction of the three-nitrophenol isomers. The nickel molybdate displays a very high activity in the catalytic reduction of the nitro functional group to an amino. The reduction progress was controlled using Ultraviolet-Visible (UV-Vis absorption.

  1. Preparation and characterization of porous reduced graphene oxide based inverse spinel nickel ferrite nanocomposite for adsorption removal of radionuclides.

    Science.gov (United States)

    Lingamdinne, Lakshmi Prasanna; Choi, Yu-Lim; Kim, Im-Soon; Yang, Jae-Kyu; Koduru, Janardhan Reddy; Chang, Yoon-Young

    2017-03-15

    For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel nickel ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel nickel ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41nm and 32.16nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333±2K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. The effect of titanium nickel nitride decorated carbon nanotubes-reduced graphene oxide hybrid support for methanol oxidation

    International Nuclear Information System (INIS)

    Liu, Gen; Pan, Zhanchang; Li, Wuyi; Yu, Ke; Xia, Guowei; Zhao, Qixiang; Shi, Shikun; Hu, Guanghui; Xiao, Chumin; Wei, Zhigang

    2017-01-01

    Highlights: • TiNiN/CNT-rGO support with an interactive three-dimensional structure and high surface area was synthesized. • Pt nanoparticles with small size were well dispersed on TiNiN/CNT-rGO support. • Pt/TiNiN/CNT-rGO shows remarkably enhanced methanol oxidation activity and durability. - Abstract: Titanium nickel nitride (TiNiN) decorated three-dimensional (3D) carbon nanotubes-reduced graphene oxide (CNT-rGO), a fancy 3D platinum (Pt)-based catalyst hybrid support, is prepared by a solvothermal process followed by a nitriding process, which is tested as anodic catalyst support for the methanol oxidation reaction (MOR). The structure, morphology and composition of the synthesized TiNiN/CNT-rGO exhibits a uniform particle dispersion with high purity and interpenetrating 3D network structure. Notably, Pt/TiNiN/CNT-rGO catalyst exhibits significantly improved catalytic activity and durability for methanol oxidation in comparison with Pt/CNT-rGO and conventional Pt/C (JM). The outstanding electrochemical performance was attributed to structure and properties. That is, the 3D CNT-rGO provided a fast transport network for charge-transfer and mass-transfer as well as TiNiN NPs with good synergistic effect and the strong electronic coupling between different domains in TiNiN/CNT-rGO, thus the catalytic activity of the novel catalyst is greatly improved. These results evidences 3D TiNiN/CNT-rGO as a promising catalyst support for a wide range of applications in fuel cells.

  3. The effect of titanium nickel nitride decorated carbon nanotubes-reduced graphene oxide hybrid support for methanol oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Gen [School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China); Pan, Zhanchang, E-mail: panzhanchang@163.com [School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China); Li, Wuyi; Yu, Ke [School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China); Xia, Guowei; Zhao, Qixiang; Shi, Shikun [Victory Giant Technology (Hui Zhou) Co., Ltd., Huizhou 516083 (China); Hu, Guanghui; Xiao, Chumin; Wei, Zhigang [School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China)

    2017-07-15

    Highlights: • TiNiN/CNT-rGO support with an interactive three-dimensional structure and high surface area was synthesized. • Pt nanoparticles with small size were well dispersed on TiNiN/CNT-rGO support. • Pt/TiNiN/CNT-rGO shows remarkably enhanced methanol oxidation activity and durability. - Abstract: Titanium nickel nitride (TiNiN) decorated three-dimensional (3D) carbon nanotubes-reduced graphene oxide (CNT-rGO), a fancy 3D platinum (Pt)-based catalyst hybrid support, is prepared by a solvothermal process followed by a nitriding process, which is tested as anodic catalyst support for the methanol oxidation reaction (MOR). The structure, morphology and composition of the synthesized TiNiN/CNT-rGO exhibits a uniform particle dispersion with high purity and interpenetrating 3D network structure. Notably, Pt/TiNiN/CNT-rGO catalyst exhibits significantly improved catalytic activity and durability for methanol oxidation in comparison with Pt/CNT-rGO and conventional Pt/C (JM). The outstanding electrochemical performance was attributed to structure and properties. That is, the 3D CNT-rGO provided a fast transport network for charge-transfer and mass-transfer as well as TiNiN NPs with good synergistic effect and the strong electronic coupling between different domains in TiNiN/CNT-rGO, thus the catalytic activity of the novel catalyst is greatly improved. These results evidences 3D TiNiN/CNT-rGO as a promising catalyst support for a wide range of applications in fuel cells.

  4. Preparation and characterization of porous reduced graphene oxide based inverse spinel nickel ferrite nanocomposite for adsorption removal of radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Lingamdinne, Lakshmi Prasanna; Choi, Yu-Lim [Department of Environmental Engineering, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Kim, Im-Soon [Graduate School of Environmental Studies, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Yang, Jae-Kyu [Ingenium College of Liberal Arts, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Koduru, Janardhan Reddy, E-mail: reddyjchem@gmail.com [Graduate School of Environmental Studies, Kwangwoon University, Seoul, 139-701 (Korea, Republic of); Chang, Yoon-Young, E-mail: yychang@kw.ac.kr [Department of Environmental Engineering, Kwangwoon University, Seoul, 139-701 (Korea, Republic of)

    2017-03-15

    Highlights: • Novel porous Ferromagnetic, GONF and Superparamagnetic, rGONF preparation. • The nanosize particles GONF (41.14 nm) and rGONF (32.16 nm) preparation. • Adsorption mechanism and modeling developments for radionuclides. • Zeta potential and surface site density of nanocomposites for comparison. - Abstract: For the removal of uranium(VI) (U(VI)) and thorium(IV) (Th(IV)), graphene oxide based inverse spinel nickel ferrite (GONF) nanocomposite and reduced graphene oxide based inverse spinel nickel ferrite (rGONF) nanocomposite were prepared by co-precipitation of GO with nickel and iron salts in one pot. The spectral characterization analyses revealed that GONF and rGONF have a porous surface morphology with an average particle size of 41.41 nm and 32.16 nm, respectively. The magnetic property measurement system (MPMS) studies confirmed the formation of ferromagnetic GONF and superparamagnetic rGONF. The adsorption kinetics studies found that the pseudo-second-order kinetics was well tune to the U(VI) and Th(IV) adsorption. The results of adsorption isotherms showed that the adsorption of U(VI) and Th(IV) were due to the monolayer on homogeneous surface of the GONF and rGONF. The adsorptions of both U(VI) and Th(IV) were increased with increasing system temperature from 293 to 333 ± 2 K. The thermodynamic studies reveal that the U(VI) and Th(IV) adsorption onto GONF and rGONF was endothermic. GONF and rGONF, which could be separated by external magnetic field, were recycled and re-used for up to five cycles without any significant loss of adsorption capacity.

  5. Surface preparation process of a uranium titanium alloy, in particular for chemical nickel plating

    International Nuclear Information System (INIS)

    Henri, A.; Lefevre, D.; Massicot, P.

    1987-01-01

    In this process the uranium alloy surface is attacked with a solution of lithium chloride and hydrochloric acid. Dissolved uranium can be recovered from the solution by an ion exchange resin. Treated alloy can be nickel plated by a chemical process [fr

  6. Nickel tungstate (NiWO4) nanoparticles/graphene composites: preparation and photoelectrochemical applications

    Science.gov (United States)

    Hosseini, Seyyedamirhossein; Farsi, Hossein; Moghiminia, Shokufeh; Zubkov, Tykhon; Lightcap, Ian V.; Riley, Andrew; Peters, Dennis G.; Li, Zhihai

    2018-05-01

    Nickel tungstate/graphene composite was synthesized in various compositions with application of a hydrothermal method. Chemical composition and morphology of each sample was studied via application of x-ray diffraction and transmission electron microscopy techniques. In the continuous, a photosystem was obtained by deposition of composite sample on a fluorine-doped tin oxide electrode with application of electrophoretic method. Electrode morphology was studied by employment of atomic force microscopy and SEM techniques. Eventually, light conversion properties and involved mechanism of fabricated photosystem was studied with application of the Mott–Schottky method. Our results confirmed that the optimum ratio between graphene and nickel tungstate is in the regime of 1:1.

  7. A novel precursor in preparation and characterization of nickel oxide nanoparticles via thermal decomposition approach

    International Nuclear Information System (INIS)

    Salavati-Niasari, Masoud; Mir, Noshin; Davar, Fatemeh

    2010-01-01

    In order to raise the need of co-surfactant in the synthesis of NiO nanoparticles, [bis(2-hydroxy-1-naphthaldehydato)nickel(II)] complex was employed as a novel precursor in thermal decomposition process using oleylamine (C 18 H 37 N) as surfactant. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible (UV-Vis) spectroscopy. Also the novel precursor thermally was treated in solid state reaction in different temperature, 400, 500, and 600 o C. Synthesized nickel oxide nanoparticles have a cubic phase with average size of 15-20 nm.

  8. In situ preparation of nickel/carbon core–shell structure by chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Fuyang [Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Superconductivity and New Energy R and D Center, Southwest Jiaotong University, Chengdu 610031 (China); Jiang, Qi, E-mail: jiangqi66@163.com [Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Superconductivity and New Energy R and D Center, Southwest Jiaotong University, Chengdu 610031 (China); Fang, Yuan; Ban, Shengguang; Ou, Shisheng; Qian, Hongxia [Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Superconductivity and New Energy R and D Center, Southwest Jiaotong University, Chengdu 610031 (China); Zhao, Yong [School of Materials Science and Engineering, University of New South Wales, Sydney, 2052 NSW (Australia)

    2013-10-15

    Nickel/carbon core–shell structure with uniform diameter has been synthesized by galvanostatic electrodeposition nickel on its surface followed by chemical vapor deposition. We proposed the growth mechanism of the core–shell structure that the precipitation of carbon from metal catalysts during the high temperature growth period lifts up metal particles leading to the formation of core–shell structure or carbon nanotubes with respect to the diameter of catalyst particles. The substrate with deposited nickel was characterized by optical microscope. The elements and features of the substrate were studied by energy dispersive X-ray spectroscopy and X-ray diffraction respectively. The morphology of the resulting material was examined by field emitting scanning electron microscopy. In addition, the electrochemical performance of the core–shell structure modified electrodes was also investigated. The result shows that electrodes modified with core structure have better electrochemical property than the bare electrodes in the [Fe(CN){sub 6}]{sup 3−}/[Fe(CN){sub 6}]{sup 4−} solution at a scan rate of 20 mV s{sup −1}.

  9. High electrocatalytic performance of nitrogen-doped carbon nanofiber-supported nickel oxide nanocomposite for methanol oxidation in alkaline medium

    Energy Technology Data Exchange (ETDEWEB)

    Al-Enizi, Abdullah M. [Department of Chemistry, King Saud University, PO Box: 2455, Riyadh 11451 (Saudi Arabia); Elzatahry, Ahmed A., E-mail: aelzatahry@ksu.edu.sa [Materials Science and Technology Program, College of Arts and Science, Qatar University, Doha 2713 (Qatar); Advanced Technology and New Materials Research Institute, City of Scientific Research and Technology Applications, New Borg El-Arab City, Alexandria 21934 (Egypt); Abdullah, Aboubakr M., E-mail: bakr@qu.edu.qa [Center for Advanced Materials, Qatar University, Doha 2713 (Qatar); Vinu, Ajayan [Future Industries Institute, University of South Australia, Building X-X2-09, Mawson Lakes Campus, Mawson Lakes 5095 SA (Australia); Iwai, Hideo [Materials Analysis Station, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047 (Japan); Al-Deyab, Salem S. [Petrochemical Research Chair, Department of Chemistry, King Saud University, PO Box: 2455, Riyadh 11451 (Saudi Arabia)

    2017-04-15

    Highlights: • A mixture of Polyvinylpyrrolidone (PVP), graphene and emeraldine base polyaniline (PANi) was electrospun and used as starting materials to prepare a nitrogen-doped carbon nanofiber (N-CNF). • Nickel oxide was loaded on the N-CNF to form a nanocomposite which was calcined later at different temperatures. • The effect of calcination temperature on the electrocatalytic behavior of the nanocomposite was studied which shows that the nanocomposite calcined at 500 °C was proved to be very high compared to the other calcination temperatures. • The stability of catalyst was excellent and its resistance to the adsorption of the intermediates generated from the methanol oxidation was very high. - Abstract: Nitrogen-Doped Carbon Nanofiber (N-CNF)–supported NiO composite was prepared by electrospinning a sol-gel mixture of graphene and polyaniline (PANi) with aqueous solutions of Polyvinylpyrrolidone (PVP) followed by a high-temperature annealing process. The electrospun was stabilized for 2 h at 280 °C, carbonized for 5 h at 1200 °C then loaded by 10% NiO. The electrocatalytic activities of the produced nanocomposite have been studied using cyclic voltammetry, and chronoamperometry. Also, N-CNF was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), surface area (BET), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and scanning-electron microscopy (SEM). The obtained N-doped carbon nanofiber was found to have a nitrogen content of 2.6 atomic% with a diameter range of (140–160) nm, and a surface area (393.3 m{sup 2} g{sup −1}). In addition, it showed a high electrocatalytic behavior towards methanol oxidation reaction in alkaline medium and high stability and resistivity to the adsorption of intermediates.

  10. Effect of pyrolysis temperature on the properties of carbon/nickel nanocomposites prepared by sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Mansour, N. Ben, E-mail: Nabil.Benmansour@fsg.rnu.tn [Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE), Gabès University, Faculty of Sciences in Gabès, Gabès (Tunisia); Najeh, I.; Mansouri, S. [Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE), Gabès University, Faculty of Sciences in Gabès, Gabès (Tunisia); El Mir, L. [Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE), Gabès University, Faculty of Sciences in Gabès, Gabès (Tunisia); Al Imam Mohammad Ibn Saud Islamic University (IMSIU), College of Sciences, Department of Physics, Riyadh 11623 (Saudi Arabia)

    2015-05-15

    Highlights: • Synthesis of nickel oxide nanoparticles in carbon structures. • Presence of multiwall carbon nanotubes (MWNT) around Ni nanoparticles for the sample treated at high pyrolysis temperature. • DC conductivity exhibited the presence of conduction percolation phenomenon and the dominance of conduction model 3D-GVRH in the studied materials. • From AC conductance PF/Ni nanocomposites have two behaviors: semiconductor and metal, depending on the pyrolysis temperature. • Appearance of a negative differential resistance (NDR) at room temperature in the sample treated at 600 °C. - Abstract: Carbon–nickel nanocomposites (C/Ni) were prepared by sol–gel method after the incorporation of nickel oxide (NiO) nanoparticles in organic matrix based on pyrogallol-formaldehyde (PF). The nanocomposites heated under inert atmosphere have been characterized by various techniques such as X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), and electrical analysis. The XRD spectra exhibited the presence of NiO or metallic Ni phase in amorphous carbon matrix at low pyrolysis temperature, while at 1000 °C the graphite structure line was observed. The TEM images indicate the presence of multiwall carbon nanotubes (MWNT) around Ni nanoparticles for the sample treated at high pyrolysis temperature. The AC conductance shows that our nanocomposites have two behaviors: semiconductor and metal, depending on the pyrolysis temperature. The voltage–current V(I) characteristics of the compound show two different regions: an Ohmic region at low current and a negative differential resistance (NDR) region at higher current. This switching phenomenal behavior has been explained by an electrothermal model.

  11. Nickel Allergy

    Science.gov (United States)

    ... nickel may, in part, be inherited. Sources of nickel exposure Common items that may expose you to nickel ... items. The following tips may help you avoid nickel exposure: Wear hypoallergenic jewelry Avoid jewelry that contains nickel. ...

  12. High-Purity Nickel Prepared by Electron Beam Melting: Purification Mechanism

    Science.gov (United States)

    Zhang, Tao; Shang, Zaiyan; Chen, Ming; He, Jinjiang; Lv, Baoguo; Wang, Xingquan; Xiong, Xiaodong

    2013-12-01

    A bulk cylindrical high-purity nickel ingot, with purity of more than 99.999 pct (5N) in mass, was obtained from the raw nickel with 99.95 pct (3N5) initial purity by virtue of double electron beam melting (EBM). A chemical analysis was performed by using glow discharge mass spectrometry (GDMS) analysis for all elements in the periodic table except carbon, nitrogen, and oxygen, which were tested by the high-performance combustion and fusion method. The major impurities B, Na, Al, Si, P, S, Ca, Ti, Cr, Fe, Cu, Co, Zn, As, Ag, Sb, and Pb showed an excellent removal effect with removal efficiency of more than 85 pct following the double EBMs. Li, Mg, Cl, K, V, Mn, Ga, Ge, Cd, Se, In, Sn, Tl, Au, and Pt were below the detection limit. No significant change in concentration was found for the refractory elements W, Mo, Ta, Nb, and Ir. Be, F, Sc, Se, Br, Rb, Sr, Zr, Y, Ru, Rh, Pd, Te, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Re, Os, Hg, Bi, Th, and U were not detectable following the purification as compared to the raw nickel. Gaseous impurities, C, N, O, especially for N, was removed sufficiently. Theoretical calculations for removal efficiency of impurity Fe based on the calculated vapor pressure, activity coefficient, and melt temperature were in good agreement with measured results, and the purification mechanism was ascribed to the evaporation of major impurities and subsequently evacuation by repetitive EBM.

  13. Ultrasonic preparation of nano-nickel/activated carbon composite using spent electroless nickel plating bath and application in degradation of 2,6-dichlorophenol.

    Science.gov (United States)

    Su, Jingyu; Jin, Guanping; Li, Changyong; Zhu, Xiaohui; Dou, Yan; Li, Yong; Wang, Xin; Wang, Kunwei; Gu, Qianqian

    2014-11-01

    Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine-formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AC). PdCl2 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2,6-dichlorophenol. Copyright © 2014. Published by Elsevier B.V.

  14. Preparation of self-supporting thin metal target films

    International Nuclear Information System (INIS)

    Wang Xiuying; Ge Suxian; Yin Jianhua; Yin Xu; Jin Genming

    1989-01-01

    The preparation method and equipment for thin metal self-supporting target without oil contamination are described. The influence of target films contaminated by oil vapor on accuracy of nuclear-physics experimental data are also discussed. The analytical results on carbon content in the prepared films of three elements show that the equipment is very effective for eliminating contamination

  15. Binding of nickel and zinc ions with activated carbon prepared from sugar cane fibre (Saccharum officinarum L.

    Directory of Open Access Journals (Sweden)

    E.U. Ikhuoria

    2007-04-01

    Full Text Available Activated carbon was prepared from sugar cane fibre by carbonizing at 500 oC for 30 minutes. This was followed by activation with ammonium chloride. The activated carbon was characterised in terms of pH, bulk density, ash content, surface area and surface charge. Equilibrium sorption of nickel and zinc ions by the activated carbon was studied using a range of metal ion concentrations. The sorption data was observed to have an adequate fit for the Langmuir isotherm equation. The level of metal ion uptake was found to be of the order: Ni2+ > Zn2+. The difference in the removal efficiency could be explained in terms of the hydration energy of the metal ions. The distribution coefficient for a range of concentration of the metal ions at the sorbent water interface is found to be higher than the concentration in the continuous phase.

  16. Preparation and magnetic properties of polymer magnetic composites based on acrylate resin filled with nickel plating graphite nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yi, E-mail: zhangyi520love@yahoo.com.cn [Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an 710072 (China); Qi Shuhua; Zhang Fan; Yang Yongqing; Duan Guochen [Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an 710072 (China)

    2011-11-01

    Nickel plating graphite nanosheets (Ni/GNs) were prepared by electroless plating method using graphite nanosheets (GNs). Then a novel polymer magnetic composites based on acrylate pressure-sensitive adhesive (acrylate PSA) filled with Ni/GNs were fabricated by solution blend method. The Ni/GNs and acrylate PSA/Ni/GNs composites were characterized by scanning electron microscope (SEM)/energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscope (TEM). All results showed that relatively uniform and compact Ni layer is successfully coated onto GNs under the given conditions, furthermore, Ni/GNs are homogeneously dispersed in acrylate PSA. The VSM results showed that the saturation magnetization of acrylate PSA/Ni/GNs composites increases with an increasing content of Ni/GNs while the coercivity decreases with an increasing content of Ni/GNs. When the content of GNs is 20 wt%, acrylate PSA/Ni/GNs composites exhibites good mechanical properties.

  17. Preparation and magnetic properties of polymer magnetic composites based on acrylate resin filled with nickel plating graphite nanosheets

    International Nuclear Information System (INIS)

    Zhang Yi; Qi Shuhua; Zhang Fan; Yang Yongqing; Duan Guochen

    2011-01-01

    Nickel plating graphite nanosheets (Ni/GNs) were prepared by electroless plating method using graphite nanosheets (GNs). Then a novel polymer magnetic composites based on acrylate pressure-sensitive adhesive (acrylate PSA) filled with Ni/GNs were fabricated by solution blend method. The Ni/GNs and acrylate PSA/Ni/GNs composites were characterized by scanning electron microscope (SEM)/energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscope (TEM). All results showed that relatively uniform and compact Ni layer is successfully coated onto GNs under the given conditions, furthermore, Ni/GNs are homogeneously dispersed in acrylate PSA. The VSM results showed that the saturation magnetization of acrylate PSA/Ni/GNs composites increases with an increasing content of Ni/GNs while the coercivity decreases with an increasing content of Ni/GNs. When the content of GNs is 20 wt%, acrylate PSA/Ni/GNs composites exhibites good mechanical properties.

  18. Preparation of nickel-coated titanium carbide particulates and their use in the production of reinforced iron matrix composites

    International Nuclear Information System (INIS)

    Yi, Danqing; Yu, Pengchao; Hu, Bin; Liu, Huiqun; Wang, Bin; Jiang, Yong

    2013-01-01

    Highlights: • Ni-coated TiC composite powders were prepared by electroless plating. • Iron-based composites reinforced by TiC particles was prepared by HIP. • Mechanical and wear properties were improved with the addition of Ni-coated TiC. • The nickel coating promotes the formation and growth of sintering neck. - Abstract: Ni-coated titanium carbide (TiC) composite powders were prepared by electroless plating (EP). Further, using hot isostatic pressing (HIP), iron matrix composites reinforced with 4 wt% Ni-coated TiC particulates with relative density close to 100% were prepared. The microstructure and phase composition of the Ni-coated powders and the composites were analyzed using X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The results showed that the TiC particles were distributed uniformly in the matrix and were free of segregation or coarsening. Compared to the TiC particles without Ni coating, the reinforced iron-based composites containing the Ni-coated particles showed higher relative densities and better mechanical properties. The density, hardness, tensile strength, and elongation were enhanced to 99.98%, 243 HV, 565 MPa, and 11.7%, respectively in composites containing Ni-coated TiC particles from 99.70%, 210 HV, 514 MPa, and 10.3%, respectively in composites that were prepared using particles without Ni coating. In addition, the mass losses in the composites containing the Ni-coated particles were reduced by 32–75% in the abrasive wear test with various vertical loads. We propose that the nickel coatings on the particulates had a beneficial effect on the microstructure and properties of the reinforced iron-based composites is due to promotion of neck formation and growth between TiC and iron powders during sintering, which enhanced the density of the sintered compact and the bonding strength between the TiC particles and the iron matrix

  19. How nitric oxide affects the decomposition of supported nickel nitrate to arrive at highly dispersed catalysts

    NARCIS (Netherlands)

    Sietsma, J.R.A.; Friedrich, H.; Broersma, A.; Versluijs-Helder, M.; van Dillen, A.J.; de Jongh, P.E.; de Jong, K.P.

    2008-01-01

    An explanation is put forward for the beneficial effect of thermal decomposition of supported Ni3(NO3)2(OH)4 in NO/He flow (0.1–1 vol%) that enables preparation of well-dispersed (3–5 nm particles) 24 wt% Ni-catalysts via impregnation and drying using aqueous [Ni(OH2)6](NO3)2 precursor solution.

  20. Sterically Hindered Square-Planar Nickel(II) Organometallic Complexes: Preparation, Characterization, and Substitution Behavior

    Science.gov (United States)

    Martinez, Manuel; Muller, Guillermo; Rocamora, Merce; Rodriguez, Carlos

    2007-01-01

    The series of experiments proposed for advanced undergraduate students deal with both standard organometallic preparative methods in dry anaerobic conditions and with a kinetic study of the mechanisms operating in the substitution of square-planar complexes. The preparation of organometallic compounds is carried out by transmetallation or…

  1. Electrochemical characteristics of silver- and nickel-coated synthetic graphite prepared by a gas suspension spray coating method for the anode of lithium secondary batteries

    International Nuclear Information System (INIS)

    Choi, Won Chang; Byun, Dongjin; Lee, Joong Kee; Cho, Byung won

    2004-01-01

    Four kinds of synthetic graphite coated with silver and nickel for the anodes of lithium secondary batteries were prepared by a gas suspension spray coating method. The electrode coated with silver showed higher charge-discharge capacities due to a Ag-Li alloy, but rate capability decreased at higher charge-discharge rate. This result can be explained by the formation of an artificial Ag oxidation film with higher impedance, this lowered the rate capability at high charge-discharge rate due to its low electrical conductivity. Rate capability is improved, however, by coating nickel and silver together on the surface of synthetic graphite. The nickel which is inactive with oxidation reaction plays an important role as a conducting agent which enhanced the conductivity of the electrode

  2. Toxicity of nickel-spiked freshwater sediments to benthic invertebrates-Spiking methodology, species sensitivity, and nickel bioavailability

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Kemble, Nile E.; Ivey, Chris D.; Kunz, James L.; Ingersoll, Christopher G.; Rudel, David

    2011-01-01

    This report summarizes data from studies of the toxicity and bioavailability of nickel in nickel-spiked freshwater sediments. The goal of these studies was to generate toxicity and chemistry data to support development of broadly applicable sediment quality guidelines for nickel. The studies were conducted as three tasks, which are presented here as three chapters: Task 1, Development of methods for preparation and toxicity testing of nickel-spiked freshwater sediments; Task 2, Sensitivity of benthic invertebrates to toxicity of nickel-spiked freshwater sediments; and Task 3, Effect of sediment characteristics on nickel bioavailability. Appendices with additional methodological details and raw chemistry and toxicity data for the three tasks are available online at http://pubs.usgs.gov/sir/2011/5225/downloads/.

  3. Support and Pretreatment Effects on the Hydrotreating Activity of SBA-15 and CMK-5 Supported Nickel Phosphide Catalysts

    Czech Academy of Sciences Publication Activity Database

    Korányi, T.I.; Vít, Zdeněk; Nagy, J.B.

    2008-01-01

    Roč. 130, č. 1 (2008), s. 80-85 ISSN 0920-5861 R&D Projects: GA ČR GA104/06/0870 Institutional research plan: CEZ:AV0Z40720504 Keywords : nickel phosphide * hydrodesulfurization * HDN of pyridine Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 3.004, year: 2008

  4. Sintering and microstructure evolution of columnar nickel-based superalloy sheets prepared by EB-PVD

    International Nuclear Information System (INIS)

    Chen, S.; Qu, S.J.; Liang, J.; Han, J.C.

    2010-01-01

    Research highlights: → EB-PVD technology is commonly used to deposit thermal barrier coatings (TBCs) and columnar structure is commonly seen in EB-PVD condensates. The unique columnar structure can provide outstanding resistance against thermal shock and mechanical strains for TBCs. However, a number of researchers have found that the columnar structure can affect the mechanical properties of EB-PVD alloy thin sheet significantly. As yet, works on how to reduce this kind of effects are seldom done. In the present article, we tried to reveal the sintering effects on microstructure evolution and mechanical properties of columnar Ni-based superalloy sheet. The results suggests that after sintering, the columnar structure degrades. Degradation depends on sintering temperature and time. Both the ultimate tensile strength and the elongation percentage are effectively improved after sintering. - Abstract: A ∼0.15 mm-thick columnar nickel-based superalloy sheet was obtained by electron beam physical vapor deposition (EB-PVD). The as-deposited alloy sheet was sintered at different conditions. The microstructure of the specimens before and after sintering was characterized by using scanning electron microscopy. An X'Pert texture facility was used to determine the crystallographic orientation of the as-deposited alloy sheet. The phase transformation was investigated by X-ray diffraction. Tensile tests were conducted at room temperature on as-deposited and sintered specimens. The results show that the as-deposited sheet is composed of typical columnar structures. After sintering, however, the columnar structure degrades. The degradation depends on sintering temperature and time. Both the ultimate tensile strength and the elongation percentage are effectively improved after sintering.

  5. Behavior of nickel catalysts in supercritical water gasification of glucose: Influence of support

    International Nuclear Information System (INIS)

    Lu, Youjun; Zhu, Yiming; Li, Sha; Zhang, Ximin; Guo, Liejin

    2014-01-01

    The catalytic performance of Ni-based supercritical water gasification (SCWG) catalysts may be influenced strongly by the nature of support. In this paper, Ni catalysts with the different supports (CeO 2 /Al 2 O 3 , La 2 O 3 /Al 2 O 3 , MgO/Al 2 O 3 , ZrO 2 /Al 2 O 3 ) were prepared by two-step impregnation method. The fresh and used catalysts were characterized by X-ray diffraction patterns (XRD), scanning electron microscopy with an Energy Dispersive X-ray (SEM-EDX), Brunauer–Emmett–Teller (BET) specific surface area measurements, X-ray photoelectron spectroscopy (XPS) and Thermo-gravimetric analyses (TGA). The catalyst performance testing was conducted by SCWG of glucose at 673 K and 23.5 MPa with an autoclave reactor, to evaluate the influence of support on the hydrogen production. The results showed that H 2 yield for different supports decreased in order: CeO 2 /Al 2 O 3  > La 2 O 3 /Al 2 O 3  > MgO/Al 2 O 3  > Al 2 O 3  > ZrO 2 /Al 2 O 3 , and H 2 selectivity decreased in order: CeO 2 /Al 2 O 3  > La 2 O 3 /Al 2 O 3  > ZrO 2 /Al 2 O 3  > Al 2 O 3  > MgO/Al 2 O 3 . Ni catalysts were deactivated in SCWG reaction because of sintering and coke deposition. Compared with other supports, CeO 2 can be used as the promoter of carbon removal from catalyst surfaces. - Highlights: • Ni catalysts with different supports were prepared by two-step impregnation method. • The fresh and used catalysts were characterized by XRD, BET, SEM, XPS and TGA. • The influences of support on hydrogen production were evaluate by SCWG of glucose. • The order of hydrogen yield and selectivity for different supports was obtained. • CeO 2 can be used as the promoter of carbon removal from catalyst surfaces

  6. Preparation and properties of a novel macro porous Ni2+-imprinted chitosan foam adsorbents for adsorption of nickel ions from aqueous solution.

    Science.gov (United States)

    Guo, Na; Su, Shi-Jun; Liao, Bing; Ding, Sang-Lan; Sun, Wei-Yi

    2017-06-01

    In this study, novel macro porous Ni 2+ -imprinted chitosan foam adsorbents (F-IIP) were prepared using sodium bicarbonate and glycerine to obtain a porogen for adsorbing nickel ions from aqueous solutions. The use of the ion-imprinting technique for adsorbents preparation improved the nickel ion selectivity and adsorption capacity. We characterised the imprinted porous foam adsorbents in terms of the effects of the initial pH value, initial metal ion concentration, and contact time on the adsorption of nickel ions. The adsorption process was described best by Langmuir monolayer adsorption models, and the maximum adsorption capacity calculated from the Langmuir equation was 69.93mgg -1 . The kinetic data could be fitted to a pseudo-second-order equation. Our analysis of selective adsorption demonstrated the excellent preference of the F-IIP foams for nickel ions compared with other coexisting metal ions. Furthermore, tests over five cycle runs suggested that the F-IIP foam adsorbents had good durability and efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Preparation and characterization of carbon/nickel oxide nanocomposite coatings for solar absorber applications

    CSIR Research Space (South Africa)

    Roro, Kittessa T

    2012-04-01

    Full Text Available Nanocomposite materials have wide range of applications in solar energy conversion. In this work, C/NiO nanocomposite solar energy absorbing surfaces were prepared using sol-gel synthesis and deposited on aluminium substrates using a spin coater...

  8. Scanning electron microscopy investigation of canal cleaning after canal preparation with nickel titanium files

    Directory of Open Access Journals (Sweden)

    Živković Slavoljub

    2010-01-01

    Full Text Available Introduction. Root canal preparation is the most important phase of endodontic procedure and it consists of adequate canal space cleaning and shaping. In recent years, rotary instruments and techniques have gained importance because of the great efficacy, speed and safety of the preparation procedure. Objective. The aim of this research was to investigate the influence of different NiTi files on the canal wall cleaning quality, residual dentine debris and smear layer. Methods. The research was conducted on extracted human teeth in vitro conditions. Teeth were divided in 7 main groups depending on the kind of instruments used for root canal preparation: ProTaper, GT, ProFile, K-3, FlexMaster, hand ProTaper and hand GT. Root canal preparation was accomplished by crown-down technique. Prepared samples were assessed on scanning electron microscopy JEOL, JSM-6460 LV. The evaluation of dentine debris was done with 500x magnification, and the evaluation of smear layer with 1,000 times magnification. Quantitive assessment of dentine debris and smear layer was done according to the criteria of Hulsmann. Results. The least amount of debris and smear layer has been found in canals shaped with ProFile instruments, and the largest amount in canals shaped with FlexMaster instruments. Canal cleaning efficacy of hand GT and ProTaper files has been similar to cleaning efficacy of rotary NiTi files. Statistic analysis has shown a significant difference in amount of dentine debris and smear layer on the canal walls between sample groups shaped with different instruments. Conclusion. Completely clean canals have not been found in any tested group of instruments. The largest amount of debris and smear layer has been found in the apical third of all canals. The design and the type of endodontic instruments influence the efficacy of the canal cleaning.

  9. Nickel-promoted tungsten carbide catalysts for cellulose conversion: effect of preparation methods.

    Science.gov (United States)

    Ji, Na; Zheng, Mingyuan; Wang, Aiqin; Zhang, Tao; Chen, Jingguang G

    2012-05-01

    A series of Ni-promoted W(2) C catalysts was prepared by means of a post-impregnation method and evaluated for the catalytic conversion of cellulose into ethylene glycol (EG). Quite different from our previously reported Ni-W(2) C/AC catalysts, which were prepared by using the co-impregnation method, the introduction of Ni by the post-impregnation method did not cause catalyst sintering, but resulted in redispersion of the W component, which was identified and characterized by means of XRD, TEM, and CO chemisorption. The highly dispersed Ni-promoted W(2) C catalyst was very active and selective in cellulose conversion into EG, with a 100% conversion of cellulose and a 73.0% yield in EG. The underlying reason for the enhanced catalytic performance was most probably the significantly higher dispersion of active sites on the catalyst. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Support and Pretreatment Effects on the Hydrotreating Activity of SBA-15 and CMK-5 Supported Nickel Phosphide Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Korányi, T.I.; Vít, Zdeněk; Nagy, J.B.

    2007-01-01

    Roč. 130, 1 (2007) , s. 80-85 ISSN 0920-5861. [International Symposium Molecular Aspects of Catalysis by Sulfides MACS-IV /4./. Doorn, 13.05.2007-17.05.2007] R&D Projects: GA ČR(CZ) GA104/06/0870 Institutional research plan: CEZ:AV0Z40720504 Keywords : nickel phosphide * sba-15 * cmk-5 Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.764, year: 2007

  11. Preparation and characterization of nano gold supported over montmorillonite clays

    International Nuclear Information System (INIS)

    Suraja, P.V.; Binitha, N.N.; Yaakob, Z.; Silija, P.P.

    2009-01-01

    Full text: The use of montmorillonite clays as a matrix, or as a host, for obtaining intercalated/supported metal particles has potential applications in catalysis and other areas. The gold nanoparticles were obtained from the most common anionic gold precursor HAuCl 4 ·3H 2 O by deposition-precipitation (DP) methods. However, it is difficult to prepare nano scale gold catalysts supported on silica surfaces with lower isoelectric point (IEP). Homogeneous precipitation method using urea also fails on silica surfaces. Reasons for the inefficiency of these methods are the negative charge of the metal precursor as well as the support surface and the high pH required for depositing gold nanoparticles. In the present work, we use glucose as the reductant in the presence of stabilizer for preparation of nano gold supported on montmorillonite clay. Here there is no need of increasing the pH of the solution to reduce the Au 3+ ions. The prepared systems are characterized using various techniques such as using X-ray fluorescence (XRF), UV-Vis Diffuse reflectance spectra (DRS) and Fourier Transform infra red spectra (FTIR) to prove the efficiency of the present method. (author)

  12. Preparation and characterization of carbon/nickel oxide nanocomposite coatings for solar absorber applications

    Energy Technology Data Exchange (ETDEWEB)

    Roro, Kittessa T., E-mail: KRoro@csir.co.za [CSIR-National Laser Centre, P.O. Box 395, Pretoria 0001 (South Africa); Tile, Ngcali; Forbes, Andrew [CSIR-National Laser Centre, P.O. Box 395, Pretoria 0001 (South Africa); School of Physics, University of KwaZulu Natal, Private Bag X54001, Durban 5000 (South Africa)

    2012-07-01

    Nanocomposite materials have wide range of applications in solar energy conversion. In this work, C/NiO nanocomposite solar energy absorbing surfaces were prepared using sol-gel synthesis and deposited on aluminium substrates using a spin coater. The coatings were prepared from alcoholic sols based on Ni-acetate using diethalonamine as a chelating agent and polyethylene glycol (PEG) as organic template. Sucrose was used as a carbon source. Sols with different heating temperature and PEG concentrations were fabricated. Thermal analysis on the gel revealed that the xerogels weight loss stabilized at around 430 Degree-Sign C. It was found that the absorption edge shifts to the higher wavelength with an increase in the heating temperature in the temperature range studied, 300-550 Degree-Sign C, due to an increase in carbon content in the material. The main features of Raman spectra obtained from the composite films are the D and G bands, characteristic of graphitic carbon films. The G peak width narrowed while the ratio of the integrated intensities of the D and G peaks, I{sub D}/I{sub G}, increased with the heating temperature, suggesting a progressive increase of the graphitic domain within the films. The solar absorption property of the films was enhanced with the increase of PEG concentrations in the sols from 0 to 2 g and decreases with further increase of PEG. The best solar absorption, {alpha}{sub sol}, and the surface thermal emittance, {epsilon}{sub therm}, at 100 Degree-Sign C obtained were 85% and 5% for a single layer, respectively, yielding an optical selectivity S {alpha}{sub sol}/{epsilon}{sub therm} of 17.1.

  13. Preparation of supported electrocatalyst comprising multiwalled carbon nanotubes

    Science.gov (United States)

    Wu, Gang; Zelenay, Piotr

    2013-08-27

    A process for preparing a durable non-precious metal oxygen reduction electrocatalyst involves heat treatment of a ball-milled mixture of polyaniline and multiwalled carbon nanotubes in the presence of a Fe species. The catalyst is more durable than catalysts that use carbon black supports. Performance degradation was minimal or absent after 500 hours of operation at constant cell voltage of 0.40 V.

  14. Scalable Preparation of Ternary Hierarchical Silicon Oxide-Nickel-Graphite Composites for Lithium-Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang , Jing [School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing 100081 China; National Development Center of High Technology Green Materials, Beijing 100081 China; Innovation Center of Electric Vehicles, Beijing 100081 China; Bao, Wurigumula [School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing 100081 China; Ma, Lu [Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue Lemont Illinois 60439 USA; Tan, Guoqiang [School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing 100081 China; Su , Yuefeng [School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing 100081 China; National Development Center of High Technology Green Materials, Beijing 100081 China; Innovation Center of Electric Vehicles, Beijing 100081 China; Chen , Shi [School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing 100081 China; National Development Center of High Technology Green Materials, Beijing 100081 China; Innovation Center of Electric Vehicles, Beijing 100081 China; Wu , Feng [School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing 100081 China; National Development Center of High Technology Green Materials, Beijing 100081 China; Innovation Center of Electric Vehicles, Beijing 100081 China; Lu, Jun [Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue Lemont Illinois 60439 USA; Amine, Khalil [Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue Lemont Illinois 60439 USA

    2015-11-09

    Silicon monoxide is a promising anode candidate because of its high theoretical capacity and good cycle performance. To solve the problems associated with this material, including large volume changes during charge-discharge processes, we report a ternary hierarchical silicon oxide–nickel–graphite composite prepared by a facile two-step ball-milling method. The composite consists of nano-Si dispersed silicon oxides embedded in nano-Ni/graphite matrices (Si@SiOx/Ni/graphite). In the composite, crystalline nano-Si particles are generated by the mechanochemical reduction of SiO by ball milling with Ni. These nano-Si dispersed oxides have abundant electrochemical activity and can provide high Li-ion storage capacity. Furthermore, the milled nano-Ni/graphite matrices stick well to active materials and interconnect to form a crosslinked framework, which functions as an electrical highway and a mechanical backbone so that all silicon oxide particles become electrochemically active. Owing to these advanced structural and electrochemical characteristics, the composite enhances the utilization efficiency of SiO, accommodates its large volume expansion upon cycling, and has good ionic and electronic conductivity. The composite electrodes thus exhibit substantial improvements in electrochemical performance. This ternary hierarchical Si@SiOx/Ni/graphite composite is a promising candidate anode material for high-energy lithium-ion batteries. Additionally, the mechanochemical ball-milling method is low cost and easy to reproduce, indicating potential for the commercial production of the composite materials.

  15. Mesoporous silica nanoparticles supported copper(II) and nickel(II) Schiff base complexes: Synthesis, characterization, antibacterial activity and enzyme immobilization

    Science.gov (United States)

    Tahmasbi, Leila; Sedaghat, Tahereh; Motamedi, Hossein; Kooti, Mohammad

    2018-02-01

    Mesoporous silica nanoparticles (MSNs) were prepared by sol-gel method and functionalized with 3-aminopropyltriethoxysilane. Schiff base grafted mesoporous silica nanoparticle was synthesized by the condensation of 2-hydroxy-3-methoxybenzaldehyde and amine-functionalized MSNs. The latter material was then treated with Cu(II) and Ni(II) salts separately to obtain copper and nickel complexes anchored mesoporous composites. The newly prepared hybrid organic-inorganic nanocomposites have been characterized by several techniques such as FT-IR, LA-XRD, FE-SEM, TEM, EDS, BET and TGA. The results showed all samples have MCM-41 type ordered mesoporous structure and functionalization occurs mainly inside the mesopore channel. The presence of all elements in synthesized nanocomposites and the coordination of Schiff base via imine nitrogen and phenolate oxygen were confirmed. MSNs and all functionalized MSNs have uniform spherical nanoparticles with a mean diameter less than 100 nm. The as-synthesized mesoporous nanocomposites were investigated for antibacterial activity against Gram-positive (B. subtilis and S. aureus) and Gram-negative (E. coli and P. aeruginosa) bacteria, as carrier for gentamicin and also for immobilization of DNase, coagulase and amylase enzymes. MSN-SB-Ni indicated bacteriocidal effect against S.aureus and all compounds were found to be good carrier for gentamicin. Results of enzyme immobilization for DNase and coagulase and α-amylase revealed that supported metal complexes efficiently immobilized enzymes.

  16. Nickel extraction from nickel matte

    Science.gov (United States)

    Subagja, R.

    2018-01-01

    In present work, the results of research activities to make nickel metal from nickel matte are presented. The research activities were covering a) nickel matte characterization using Inductively Couple plasma (ICP), Electron Probe Micro Analyzer (EPMA) and X-Ray Diffraction (XRD), b) nickel matte dissolution process to dissolve nickel from nickel matte into the spent electrolyte solutions that contains hydrochloric acid, c) purification of nickel chloride leach solution by copper cementation process to remove copper using nickel matte, selective precipitation process to remove iron, solvent extraction using Tri normal octyl amine to separate cobalt from nickel chloride solutions and d) Nickel electro winning process to precipitate nickel into the cathode surface from purified nickel chloride solution by using direct current. The research activities created 99, 72 % pure nickel metal as the final product of the process.

  17. Effects of Support on the Performance of NiO-Based Oxygen Carriers Effets du support sur les performances de matériaux transporteurs d’oxygène à base d’oxyde de nickel

    Directory of Open Access Journals (Sweden)

    Baek J.-I.

    2011-05-01

    Full Text Available The performance of an oxygen carrier for Chemical Looping Combustion varies with the support material used. NiO oxygen carriers were prepared using 60 or 70 wt% NiO and different raw support materials (γ-Al2O3, pseudoboehmite, α-Al2O3, γ-Al2O3 mixed with MgO, hydrotalcite, MgAl2O4, and γ-Al2O3 with added graphite by the mechanical mixing method. Reactivity tests were conducted using a thermogravimetric analyzer (TGA at 950˚C. The oxygen carriers prepared using γ-Al2O3, γ-Al2O3 mixed with a small amount of MgO, hydrotalcite, and MgAl2O4 showed high oxygen transfer capacity, high oxygen utilization, and a high oxygen transfer rate. Graphite addition to γ-Al2O3 did not increase the surface area or reactivity. The use of pseudoboehmite as a support led to a significant decrease in oxygen transfer capacity and severe agglomeration of the oxygen carriers during the redox reaction. The increase in MgO content in the raw support materials decreased the reduction reactivity. The oxygen carriers prepared with α-Al2O3 showed less oxygen transfer capacity than the other oxygen carriers. The differences in the reactivity according to the support type were explained by the relative strength of NiO-support interaction obtained from the temperature-programmed reduction analysis. The reactivity test results in this work indicate that γ-Al2O3 and hydrotalcite could be desirable raw support materials to prepare highly reactive NiO oxygen carriers with high NiO content. Les performances des materiaux transporteurs d’oxygene varient en fonction du support utilise dans le procede de combustion en boucle chimique. Differents materiaux a base d’oxyde de Nickel ont ete synthetises avec des concentrations elevees en NiO, comprises entre 60 et 70 %, sur differents supports (γ-Al2O3, pseudobohemite, α-Al2O3, γ-Al2O3 melangee avec MgO, hydrotalcite, MgAl2O4 et γ-Al2O3 additivees avec du graphite par melange mecanique. Des tests de reactivite ont ete

  18. Preparation and Characterization of Sugar Based Catalyst on Various Supports

    Directory of Open Access Journals (Sweden)

    Jidon Adrian Janaun

    2017-04-01

    Full Text Available A novel structured carbon-based acid catalyst was prepared by depositing the carbon precursor onto glass, ceramic and aluminum supports via dip-coating method, followed by carbonization process for converting the d-glucose layer into black carbon char in an inert nitrogen environment at 400 °C. Then, the –SO3H group was introduced into the framework of the carbon char by multiple vapor phase sulfonation. Four different carbonization methods were carried out (dry pyrolysis and hydrothermal carbonization with or without pressurized in the catalyst preparation while among the carbonization methods, the samples which prepared from dry pyrolysis without pressurized process showed the strong acidity due to highest adsorption of acid group in the catalyst surface although the catalyst attached onto the support was the least compared to other preparation methods. Among the catalysts, the sulfonated carbon-base catalyst that is attached on the ceramic support exhibited the highest aci-dity (1.327 mmol/g followed by the catalyst deposited on the glass (0.917 mmol/g and aluminum (0.321 mmol/g supports. The porous structure of ceramic surface, allowed a better interaction between reactants and –SO3H site in the carbon. Through the FT-IR analysis, it was observed that the functional groups –COOH, –OH, and –SO3H were present in the active sites of the catalysts. The surface areas of  glass (Si–SC, ceramic (Ce–SC and aluminum (Al–SC catalysts were larger than 1 m2/g, whereas the pore size belongs to macroporous as the average pore size is more than 50 nm. It is also stable within the temperature of 400 °C as there was less than 10% weight loss revealed from the TGA analysis. Copyright © 2017 BCREC GROUP. All rights reserved Received: 20th April 2016; Revised: 14th October 2016; Accepted: 17th October 2016 How to Cite: Janaun, J.A., Mey, T.J., Bono, A., Krishnaiah, D. (2017. Preparation and Characterization of Sugar Based Catalyst on Various

  19. Corrosion resistance and long-term durability of super-hydrophobic nickel film prepared by electrodeposition process

    International Nuclear Information System (INIS)

    Khorsand, S.; Raeissi, K.; Ashrafizadeh, F.

    2014-01-01

    A super-hydrophobic nickel film with micro-nano structure was successfully fabricated by electrodeposition process. By controlling electrodeposition parameters and considering different storage times for the coatings in air, various nickel films with different wettability were fabricated. Surface morphology of nickel films was examined by means of scanning electron microscopy (SEM). The results showed that the micro-nano nickel film was well-crystallized and exhibited pine cone-like microstructure with nano-cone arrays randomly dispersed on each micro-protrusion. The wettability of the micro-nano nickel film varied from super-hydrophilicity (water contact angle 5.3°) to super-hydrophobicity (water contact angle 155.7°) by exposing the surface in air at room temperature. The corrosion resistance of the super-hydrophobic film was estimated by electrochemical impedance spectroscopy (EIS) and Tafel polarization measurements. The potentiodynamic curves revealed that the corrosion rate of superhydrophobic surface was only 0.16% of the bare copper substrate. Moreover, EIS measurements and appropriate equivalent circuit models revealed that the corrosion resistance of nickel films considerably improved with an increase in the hydrophobicity. The superhydrophobic surface also exhibited an excellent long-term durability in neutral 3.5 wt.% NaCl solution.

  20. Effect of molybdenum on microstructure and strength on nickel base titanium carbide composites prepared with self-propagating high-temperature synthesis products, TiCx-Ni

    International Nuclear Information System (INIS)

    Choi, Y.; Lee, J.K.; Mullins, M.E.

    1993-01-01

    For reinforcement of metal matrix composites, titanium carbides were prepared through a self propagating high-temperature synthesis reaction, and then consolidated into the nickel-molybdenum matrix via liquid phase sintering followed by hot isostatic pressing. As the amount of molybdenum in the matrix phase increased up to 8.5 wt.%, the average titanium carbide size decreased and the bend rupture strength of the composites increased. This was attributed not only to the solid solution hardening effect and the decrease in the carbide particle size, but also to the (Ti, Mo)C x phase which was formed around titanium carbide cores. The formation of the (Ti, Mo)C x phase was also associated with a change in fracture mode from a mixed case of both transgranular and interfacial fracture to a transgranular fracture mode upon the molybdenum addition to the titanium carbide-nickel composites

  1. Hydrodesulfurization Activities of NiMo Catalysts Supported on Mechanochemically Prepared Al‐Ce Mixed Oxides.

    Czech Academy of Sciences Publication Activity Database

    Jirátová, Květa; Spojakina, A.; Kaluža, Luděk; Palcheva, R.; Balabánová, Jana; Tyuliev, G.

    2016-01-01

    Roč. 37, č. 2 (2016), s. 258-267 ISSN 0253-9837 R&D Projects: GA ČR GAP106/11/0902 Institutional support: RVO:67985858 Keywords : nickel * molybdenum * alumina Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 2.813, year: 2016

  2. Molecularly Tailored Nickel Precursor and Support Yield a Stable Methane Dry Reforming Catalyst with Superior Metal Utilization.

    Science.gov (United States)

    Margossian, Tigran; Larmier, Kim; Kim, Sung Min; Krumeich, Frank; Fedorov, Alexey; Chen, Peter; Müller, Christoph R; Copéret, Christophe

    2017-05-24

    Syngas production via the dry reforming of methane (DRM) is a highly endothermic process conducted under harsh conditions; hence, the main difficulty resides in generating stable catalysts. This can, in principle, be achieved by reducing coke formation, sintering, and loss of metal through diffusion in the support. [{Ni(μ 2 -OCHO)(OCHO)(tmeda)} 2 (μ 2 -OH 2 )] (tmeda = tetramethylethylenediamine), readily synthesized and soluble in a broad range of solvents, was developed as a molecular precursor to form 2 nm Ni(0) nanoparticles on alumina, the commonly used support in DRM. While such small nanoparticles prevent coke deposition and increase the initial activity, operando X-ray Absorption Near-Edge Structure (XANES) spectroscopy confirms that deactivation largely occurs through the migration of Ni into the support. However, we show that Ni loss into the support can be mitigated through the Mg-doping of alumina, thereby increasing significantly the stability for DRM. The superior performance of our catalytic system is a direct consequence of the molecular design of the metal precursor and the support, resulting in a maximization of the amount of accessible metallic nickel in the form of small nanoparticles while preventing coke deposition.

  3. THERMAL STABILITY OF NICKEL AZIDES | Irom | Global Journal of ...

    African Journals Online (AJOL)

    . The samples, prepared using different methods, are fresh nickel azide, fresh nickel hydroxy axide and the third sample was obtained by ageing fresh nickel hydroxy azide for almost one year. Thermal decomposition of the samples at different ...

  4. Catalytic Reductions and Tandem Reactions of Nitro Compounds Using in Situ Prepared Nickel Boride Catalyst in Nanocellulose Solution.

    Science.gov (United States)

    Prathap, Kaniraj Jeya; Wu, Qiong; Olsson, Richard T; Dinér, Peter

    2017-09-15

    A mild and efficient method for the in situ reduction of a wide range of nitroarenes and aliphatic nitrocompounds to amines in excellent yields using nickel chloride/sodium borohydride in a solution of TEMPO-oxidized nanocellulose in water (0.01 wt %) is described. The nanocellulose has a stabilizing effect on the catalyst, which increases the turnover number and enables low loading of nickel catalyst (0.1-0.25 mol % NiCl 2 ). In addition, two tandem protocols were developed in which the in situ formed amines were either Boc-protected to carbamates or further reacted with an epoxide to yield β-amino alcohols in excellent yields.

  5. Photolysis of nickel hydroxy azide. | IROM | Global Journal of Pure ...

    African Journals Online (AJOL)

    Photolysis of nickel hydroxy azide at 380 ºK is compared with that of nickel azide under similar considerations. Nickel azide sample was prepared by adapting the method of Brauer while nickel hydroxy azide was obtained by dehydrating the dihydrate of nickel azide crystals (Ni(N3)2.2H2O) and exposing to atmospheric ...

  6. Profiling and quantitative evaluation of three Nickel-Coated magnetic matrices for purification of recombinant proteins: lelpful hints for the optimized nanomagnetisable matrix preparation

    Directory of Open Access Journals (Sweden)

    Zarei Saeed

    2011-08-01

    Full Text Available Abstract Background Several materials are available in the market that work on the principle of protein magnetic fishing by their histidine (His tags. Little information is available on their performance and it is often quoted that greatly improved purification of histidine-tagged proteins from crude extracts could be achieved. While some commercial magnetic matrices could be used successfully for purification of several His-tagged proteins, there are some which have been proved to operate just for a few extent of His-tagged proteins. Here, we address quantitative evaluation of three commercially available Nickel nanomagnetic beads for purification of two His-tagged proteins expressed in Escherichia coli and present helpful hints for optimized purification of such proteins and preparation of nanomagnetisable matrices. Results Marked differences in the performance of nanomagnetic matrices, principally on the basis of their specific binding capacity, recovery profile, the amount of imidazole needed for protein elution and the extent of target protein loss and purity were obtained. Based on the aforesaid criteria, one of these materials featured the best purification results (SiMAG/N-NTA/Nickel for both proteins at the concentration of 4 mg/ml, while the other two (SiMAC-Nickel and SiMAG/CS-NTA/Nickel did not work well with respect to specific binding capacity and recovery profile. Conclusions Taken together, functionality of different types of nanomagnetic matrices vary considerably. This variability may not only be dependent upon the structure and surface chemistry of the matrix which in turn determine the affinity of interaction, but, is also influenced to a lesser extent by the physical properties of the protein itself. Although the results of the present study may not be fully applied for all nanomagnetic matrices, but provide a framework which could be used to profiling and quantitative evaluation of other magnetisable matrices and also

  7. Co-reduction of Copper Smelting Slag and Nickel Laterite to Prepare Fe-Ni-Cu Alloy for Weathering Steel

    Science.gov (United States)

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

    2018-02-01

    In this study, a new technique was proposed for the economical and environmentally friendly recovery of valuable metals from copper smelting slag while simultaneously upgrading nickel laterite through a co-reduction followed by wet magnetic separation process. Copper slag with a high FeO content can decrease the liquidus temperature of the SiO2-Al2O3-CaO-MgO system and facilitate formation of liquid phase in a co-reduction process with nickel laterite, which is beneficial for metallic particle growth. As a result, the recovery of Ni, Cu, and Fe was notably increased. A crude Fe-Ni-Cu alloy with 2.5% Ni, 1.1% Cu, and 87.9% Fe was produced, which can replace part of scrap steel, electrolytic copper, and nickel as the burden in the production of weathering steel by an electric arc furnace. The study further found that an appropriate proportion of copper slag and nickel laterite in the mixture is essential to enhance the reduction, acquire appropriate amounts of the liquid phase, and improve the growth of the metallic alloy grains. As a result, the liberation of alloy particles in the grinding process was effectively promoted and the metal recovery was increased significantly in the subsequent magnetic separation process.

  8. Preparation of drop deposited plutonium sources on porcelain support

    International Nuclear Information System (INIS)

    Miguel, M.; Delle Site, A.; Deron, S.; Raab, W.; Swietly, H.

    1984-01-01

    Plutonium alpha spectrometry is of interest in safeguards verification, particular for the characterization of test materials for calorimetric assay of plutonium products and for the assay of spent fuel solutions by isotope dilution alpha spectrometry. Such measurements require 0.1-0.3% precision and accuracy in 238 Pu isotopic assay. The present paper reports experience with an alpha spectrometry procedure intended for routine measurements. Sources of excellent quality are prepared very simply and rapidly by drop deposition on porcelain supports. The method of preparation is described which readily produces sources with resolutions of 16 keV (fwhm). The effect of various measurement parameters, tail correction, 241 Am separation and in-growth, are presented. Results are compared with those of mass spectrometry. The relative bias between the 238 Pu/ 239 Pu isotopic ratio measured by the two techniques is of the order of +- 0.5%, with a standard deviation of 1.0%. The performance of alpha spectrometry is at present limited by the quality of the 241 Am separation. (orig.)

  9. Nanostructured Multilayer Composite Films of Manganese Dioxide/Nickel/Copper Sulfide Deposited on Polyethylene Terephthalate Supporting Substrate

    Directory of Open Access Journals (Sweden)

    Awangku Nabil Syafiq Bin Awangku Metosen

    2015-01-01

    Full Text Available Nanostructured multilayer manganese dioxide/nickel/copper sulfide (MnO2/Ni/CuS composite films were successfully deposited onto supporting polyethylene terephthalate (PET substrate through the sequential deposition of CuS, Ni, and MnO2 thin films by chemical bath deposition, electrodeposition, and horizontal submersion deposition techniques, respectively. Deposition of each thin-film layer was optimized by varying deposition parameters and conditions associated with specific deposition technique. Both CuS and Ni thin films were optimized for their electrical conductivity whereas MnO2 thin film was optimized for its microstructure and charge capacity. The electrochemical properties of nanostructured multilayer MnO2/Ni/CuS composite films were evaluated by cyclic voltammetry as electrode materials of an electrochemical capacitor prototype in a dual-planar device configuration. Cyclic voltammogram in mild Na2SO4 aqueous electrolyte exhibited a featureless and almost rectangular shape which was indicative of the ideal capacitive behavior and high cycling reversibility of the electrochemical capacitor prototype. Nanostructured multilayer MnO2/Ni/CuS composite films on supporting polyethylene terephthalate (PET substrate could potentially be utilized as electrode materials for the fabrication of high performance electrochemical capacitors.

  10. Cost effective preparation and characterization of nanocrystalline nickel ferrites (NiFe2O4 in low temperature regime

    Directory of Open Access Journals (Sweden)

    T. Shanmugavel

    2015-04-01

    Full Text Available Nanocrystalline forms of nickel ferrite (NiFe2O4 have been synthesized with the aid of single step chemical combustion method using citric acid as fuel in the 1:1 ratio. The single phase formation of nickel ferrite was confirmed through powder X-ray diffraction (XRD. The presence of various functional groups was confirmed through Fourier transform infrared spectroscopic (FTIR analysis and the compositional analysis was performed through Energy dispersive X-ray studies (EDX. The micro structural features of nanocrystallites were examined by scanning electron microscope (SEM. Surface morphology of the nanocrystalline form of NiFe2O4 was also investigated through transmission electron microscopic (TEM analysis. Magnetic measurements have showed the ferrimagnetic properties with Curie temperature @ 500 °C. The obtained results are in good agreement with the reported values. The other results have been discussed in detail.

  11. Surface areas of turbostratic graphitic carbons prepared from a resin using nickel particles, 20 nm, as graphitization catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Oya, A.; Inoue, E.; Otani, S.; Marsh, H.

    1981-11-01

    Nickel particles were used to graphitize catalytically a non-graphitizing carbon to create a turbostratic graphitic material called the T/SUB/s-component. This method was examined by X-ray diffraction. Coals on heat treatment to temperatures >1270 K form T/SUB/s-component carbons. Therefore, considerations of the properties of the T/SUB/s-component carbon may have relevance to considerations of the operational performances of blast furnace coke. (22 refs.)

  12. Electro-oxidation of methanol in alkaline conditions using Pd–Ni nanoparticles prepared from organometallic precursors and supported on carbon vulcan

    Energy Technology Data Exchange (ETDEWEB)

    Manzo-Robledo, A., E-mail: amanzor@ipn.mx [UPALM, Laboratorio de Electroquímica y Corrosión, Escuela Superior de Ingeniería Química e Industrias Extractivas-IPN (Mexico); Costa, Natália J. S. [Universidade de São Paulo, Instituto de Química (Brazil); Philippot, K. [CNRS, LCC, Laboratoire de Chimie de Coordination (France); Rossi, Liane M. [Universidade de São Paulo, Instituto de Química (Brazil); Ramírez-Meneses, E. [Universidad Iberoamericana, Departamento de Ingeniería y Ciencias Químicas (Mexico); Guerrero-Ortega, L. P. A. [UPALM, Laboratorio de Electroquímica y Corrosión, Escuela Superior de Ingeniería Química e Industrias Extractivas-IPN (Mexico); Ezquerra-Quiroga, S. [Universidad Iberoamericana, Departamento de Ingeniería y Ciencias Químicas (Mexico)

    2015-12-15

    Oxidation of low-molecular weight alcohols as energy sources using metal nanoparticles has attracted considerable interest for use as a power source in portable electronic devices. In this work, a series of mono- and bimetallic nanoparticles based on palladium and nickel (Pd, Pd{sub 90}Ni{sub 10}, Pd{sub 50}Ni{sub 50}, Pd{sub 10}Ni{sub 90}, and Ni) have been synthesized from organometallic precursors, namely tris(dibenzylideneacetone) dipalladium(0), Pd{sub 2}(dba){sub 3}, and bis(1,5-cyclooctadiene)nickel(0), Ni(cod){sub 2}. Well-defined metal particles in the nanometric scale from 4.2 to 6.3 nm were observed by transmission electron microscopy. The as-prepared nanoparticles were mixed with a carbon Vulcan matrix (10 % wt. of the catalyst in turn) for investigation as electrocatalysts in methanol oxidation reaction (MOR) in alkaline conditions. The i–E profiles from cyclic voltammetry for the monometallic systems indicated a redox process attributed only to palladium or nickel, as expected. With the bimetallic nanomaterials, the redox process and the i–E characteristics are functions of the amount of nickel associated to palladium. From a fundamental point of view, it has been established that the OH ions’ interfacial interaction and the MOR kinetics are affected by the presence of nickel (decreasing the faradic current) as supported by the current versus potential profiles obtained as a function of methanol concentration and with temperature variation.

  13. Self-Supported Ni(P, Ox·MoOx Nanowire Array on Nickel Foam as an Efficient and Durable Electrocatalyst for Alkaline Hydrogen Evolution

    Directory of Open Access Journals (Sweden)

    Wei Hua

    2017-12-01

    Full Text Available Earth-abundant and low-cost catalysts with excellent electrocatalytic hydrogen evolution reaction (HER activity in alkaline solution play an important role in the sustainable production of hydrogen energy. In this work, a catalyst of Ni(P, Ox·MoOx nanowire array on nickel foam has been prepared via a facile route for efficient alkaline HER. Benefiting from the collaborative advantages of Ni(P, Ox and amorphous MoOx, as well as three-dimensional porous conductive nickel scaffold, the hybrid electrocatalyst shows high catalytic activity in 1 M KOH aqueous solution, including a small overpotential of 59 mV at 10 mA cm−2, a low Tafel slope of 54 mV dec-1, and excellent cycling stability.

  14. MOF-derived Co-doped nickel selenide/C electrocatalysts supported on Ni foam for overall water splitting

    KAUST Repository

    Ming, Fangwang

    2016-09-01

    It is of prime importance to develop dual-functional electrocatalysts with good activity for overall water splitting, which remains a great challenge. Herein, we report the synthesis of a Co-doped nickel selenide (a mixture of NiSe and NiSe)/C hybrid nanostructure supported on Ni foam using a metal-organic framework as the precursor. The resulting catalyst exhibits excellent catalytic activity toward the oxygen evolution reaction (OER), which only requires an overpotential of 275 mV to drive a current density of 30 mA cm. This overpotential is much lower than those reported for precious metal free OER catalysts. The hybrid is also capable of catalyzing the hydrogen evolution reaction (HER) efficiently. A current density of -10 mA cm can be achieved at 90 mV. In addition, such a hybrid nanostructure can achieve 10 and 30 mA cm at potentials of 1.6 and 1.71 V, respectively, along with good durability when functioning as both the cathode and the anode for overall water splitting in basic media.

  15. Nickel-Salen supported paramagnetic nanoparticles for 6-His-target recombinant protein affinity purification.

    Science.gov (United States)

    Rashid, Zahra; Ghahremanzadeh, Ramin; Nejadmoghaddam, Mohammad-Reza; Nazari, Mahboobeh; Shokri, Mohammad-Reza; Naeimi, Hossein; Zarnani, Amir-Hassan

    2017-03-24

    In this research, a simple, efficient, inexpensive, rapid and high yield method for the purification of 6×histidine-tagged recombinant protein was developed. For this purpose, manganese ferrite magnetic nanoparticles (MNPs) were synthesized through a co-precipitation method and then they were conveniently surface-modified with tetraethyl orthosilicate (TEOS) in order to prevent oxidation and form high density of hydroxyl groups. Next, the salen ligand was prepared from condensation reaction of salicylaldehyde and 3-aminopropyl (trimethoxy) silane (APTMS) in 1:1 molar ratio; followed by complexation with Ni(OAc) 2 .4H 2 O. Finally, the prepared Ni(II)-salen complex conjugated to silica coated MNPs and MnFe 2 O 4 @SiO 2 @Ni-Salen complex nanoparticles were obtained. The functionalized nanoparticles were spherical with an average diameter around 70nm. The obtained MNPs had a saturation magnetization about 54 emu/g and had super paramagnetic character. These MNPs were used efficiently to enrich recombinant histidine-tagged (His-tagged) protein-A from bacterial cell lysate. In about 45min, highly pure His-tagged recombinant protein was obtained, as judged by SDS-PAGE analysis and silver staining. The amount of target protein in flow through and washing fractions was minimal denoting the high efficiency of purification process. The average capacity of the matrix was found to be high and about 180±15mgg -1 (protein/MnFe 2 O 4 @SiO 2 @Ni-Salen complex). Collectively, purification process with MnFe 2 O 4 @SiO 2 @Ni-Salen complex nanoparticles is rapid, efficient, selective and whole purification can be carried out in only a single tube without the need for expensive systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Nucleation and Growth of Porous MnO2 Coatings Prepared on Nickel Foam and Evaluation of Their Electrochemical Performance

    Directory of Open Access Journals (Sweden)

    Wenxin Huang

    2018-05-01

    Full Text Available Porous MnO2 was uniformly electrodeposited on nickel foam in MnSO4 solution, which was applied as the electrode of supercapacitors. The nucleation/growth mechanisms of porous MnO2 were investigated firstly. Then two kinds of electrochemical measuring technologies, corresponding to the cycle voltammetry (CV and galvanostatic charge-discharge, were adopted to assess the electrochemical performance of MnO2 electrodes. The results demonstrated that the deposition of MnO2 on nickel foam included four stages. Prior to the deposition, an extremely short incubation period of about 2 s was observed (the first stage. Then the exposed nickel foam was instantly covered by a large number of MnO2 crystal nuclei and crystal nuclei connected with each other in a very short time of about 3 s (the second stage. Nucleation predominated in the second stage. The sharply rise of current was caused by the increase in substrate surface area which due to nucleation of MnO2. Grain boundaries grew preferentially due to their high energy, accompanied with a honeycomb-like structure with the higher surface area was formed. However, accompanied with the electrochemical reactions gradually diffusion-controlled, the current presented the decline trend with increasing the time (the third stage. When the electrochemical reactions were completely diffusion-controlled, the porous MnO2 coating with an approximately constant surface area was formed (the fourth stage. MnO2 coatings deposited for different time (30, 60, 120, 300 s exhibited a similar specific capacitance (CV: about 224 F/g; galvanostatic charge-discharge: about 264 F/g. Comparatively speaking, the value of MnO2 deposited for 600 s was highest (CV: 270 F/g; galvanostatic charge-discharge: 400 F/g.

  17. Reductive deconstruction of organosolv lignin catalyzed by zeolite supported nickel nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kasakov, Stanislav; Shi, Hui; Camaioni, Donald M.; Zhao, Chen; Barath, Eszter; Jentys, Andreas; Lercher, Johannes A.

    2015-11-01

    Mechanistic aspects of deconstruction and hydrodeoxygenation of organosolv lignin using supported Ni catalysts with (Ni/HZSM-5 and Ni/HBEA) and without Brønsted acid sites (Ni/SiO2) are reported. Lignin was deconstructed and converted to saturated cyclic hydrocarbons ranging from C5 to C14. In the one-stage reaction, full conversion with total yield of 70 ± 5 wt.% saturated hydrocarbons was achieved at 593 K and 20 bar H2. The organosolv lignin used consists of seven to eight monolignol subunits and has an average molecular weight of ca. 1200 g mol-1. The monolignols were mainly guaiacyl, syringyl and phenylcoumaran, randomly interconnected through β-O-4, 4-O-5, β-1, 5-5’ and β-β ether bonds. In situ IR spectroscopy was used to follow the changes in lignin constituents during reaction. The proposed reaction pathways for the catalytic transformation of this organosolv lignin to alkanes start with the hydrogenolysis of aryl alkyl ether bonds, followed by hydrogenation of the aromatic compounds on Ni to cyclic alcohols. Oxygen is removed from the alcohols via dehydration on Brønsted acid sites to yield cyclic alkenes that are further hydrogenated to alkanes. Formation of condensation products may occur via intermolecular recombination of aromatic monomers or alkylation of aromatic compounds by alkenes. The financial support from TUM-PNNL cooperation project “Development of new methods for in situ characterization in liquid phase reactions” (CN-177939) is highly appreciated. The work by S.K., H.S., and J.A.L was partially supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences.

  18. Sintering-resistant Single-Site Nickel Catalyst Supported by Metal-Organic Framework

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhanyong; Schweitzer, Neil; League, Aaron; Bernales Candia, Sandra Varinia; Peters, Aaron; Getsoian, Andrew G.; Wang, Timothy; Miller, Jeffrey T.; Vjunov, Aleksei; Fulton, John L.; Lercher, Johannes A.; Cramer, Christopher J.; Gagliardi, Laura; Hupp, Joseph; Farha, Omar

    2016-02-17

    Developing supported single-site catalysts is an important goal in heterogeneous catalysis, since the well-defined active sites afford opportunities for detailed mechanistic studies, thereby facilitating the design of improved catalysts. We present herein a method for installing Ni ions uniformly and precisely on the node of a Zr-based MOF, NU-1000, in high density and large quantity (denoted as Ni-AIM) using atomic layer deposition (ALD) in a metal–organic framework (MOF) (AIM). Ni-AIM is demonstrated to be an efficient gas-phase hydrogenation catalyst upon activation. The structure of the active sites in Ni-AIM is proposed, revealing its single-site nature. More importantly, due to the organic linker used to construct the MOF support, the Ni ions stay isolated throughout the hydrogenation catalysis, in accord with its long-term stability. A quantum chemical characterization of the catalyst and the catalytic process complements the experimental results. With validation of computational modeling protocols, we further targeted ethylene oligomerization catalysis by Ni-AIM guided by theoretical prediction. Given the generality of the AIM methodology, this emerging class of materials should prove ripe for the discovery of new catalysts for the transformation of volatile substrates.

  19. Sintering-Resistant Single-Site Nickel Catalyst Supported by Metal-Organic Framework.

    Science.gov (United States)

    Li, Zhanyong; Schweitzer, Neil M; League, Aaron B; Bernales, Varinia; Peters, Aaron W; Getsoian, Andrew Bean; Wang, Timothy C; Miller, Jeffrey T; Vjunov, Aleksei; Fulton, John L; Lercher, Johannes A; Cramer, Christopher J; Gagliardi, Laura; Hupp, Joseph T; Farha, Omar K

    2016-02-17

    Developing supported single-site catalysts is an important goal in heterogeneous catalysis since the well-defined active sites afford opportunities for detailed mechanistic studies, thereby facilitating the design of improved catalysts. We present herein a method for installing Ni ions uniformly and precisely on the node of a Zr-based metal-organic framework (MOF), NU-1000, in high density and large quantity (denoted as Ni-AIM) using atomic layer deposition (ALD) in a MOF (AIM). Ni-AIM is demonstrated to be an efficient gas-phase hydrogenation catalyst upon activation. The structure of the active sites in Ni-AIM is proposed, revealing its single-site nature. More importantly, due to the organic linker used to construct the MOF support, the Ni ions stay isolated throughout the hydrogenation catalysis, in accord with its long-term stability. A quantum chemical characterization of the catalyst and the catalytic process complements the experimental results. With validation of computational modeling protocols, we further targeted ethylene oligomerization catalysis by Ni-AIM guided by theoretical prediction. Given the generality of the AIM methodology, this emerging class of materials should prove ripe for the discovery of new catalysts for the transformation of volatile substrates.

  20. Redox cycling performance of inert-substrate-supported tubular single cells with nickel anode current collector

    Science.gov (United States)

    Zhao, Kai; Kim, Bok-Hee; Xu, Qing; Du, Yanhai; Ahn, Byung-Guk

    2015-10-01

    An inert-substrate-supported tubular single cell, with a configuration of porous yttria-stabilized zirconia (YSZ) supporter/Ni anode current collector/Ni-Ce0.8Sm0.2O1.9 anode/YSZ/Ce0.8Sm0.2O1.9 bi-layer electrolyte/La0.6Sr0.4Co0.2Fe0.8O3-δ cathode, has been fabricated by extrusion and dip-coating techniques. Thickness of the Ni layer is modified by controlling the number of dip-coatings from one to four. Electrochemical performance and redox cycling stability of the single cell are investigated with respect to the microstructure of the Ni layer. Increasing the thickness of the Ni layer enhances the maximum power density of the cell, while it is unfavorable for the redox cycling stability. Considering the trade-off between these two aspects, an optimum dip-coating time is determined to be two. The cell shows a reasonable maximum power density of 453 mW cm-2 at 800 °C, as well as good redox cycling stability within eight redox cycles. Additionally, 10 vol.% Ce0.8Sm0.2O1.9 ceramic particle is incorporated into the Ni layer to further improve the redox cycling stability. The cell exhibits enhanced redox cycling performance after the Ce0.8Sm0.2O1.9 incorporation. Within seven redox cycles, the cell voltage loss is less than 1% at a current density of 400 mA cm-2, and it maintains 93% of its initial performance after 11 redox cycles.

  1. Preparation of nickel ferrite/carbon nanotubes composite by microwave irradiation technique for use as catalyst in photo-fenton reaction

    Energy Technology Data Exchange (ETDEWEB)

    Foletto, E.L.; Rigo, C.; Severo, E.C.; Mazutti, M.A.; Dotto, G.L.; Jahn, S.L.; Sales, J.C. [Universidade Federal de Santa Maria (UFSM), RS (Brazil); Chiavone-Filho, O. [Universidade Federal do Rio Grande do Sul (UFRGS), RS (Brazil); Gundel, A.; Lucchese, M. [Universidade Federal do Pampa (UNIPAMPA), Bage, RS (Brazil)

    2016-07-01

    Full text: Nickel ferrite/multi-walled carbon nanotubes (NiFe2O4/MWCNTs) composite has been rapidly synthesized via microwave irradiation technique. The structural properties of the formed product was investigated by X-ray diffraction (XRD), N2 adsorption/desorption isotherms, thermogravimetric analysis (TGA), Raman spectroscopy and, scanning electron microscopy (SEM). The catalytic behavior of composite material was evaluated by the degradation of Amaranth dye in the photo-Fenton reaction under visible light irradiation. The overall results showed that the prepared composite was successfully synthesized, demonstrating good performance in the dye degradation, with higher degradation rate compared to the NiFe2O4. The high efficiency in dye degradation can be attributed to synergism between NiFe2O4 and MWCNTs. Therefore, NiFe2O4/MWCNTs composite can be used as promising photo-Fenton catalyst to degrade Amaranth dye from aqueous solutions. (author)

  2. Preparation and electrocatalytic oxidation properties of a nickel pentacyanonitrosylferrate modified carbon composite electrode by two-step sol-gel technique: improvement of the catalytic activity

    International Nuclear Information System (INIS)

    Salimi, Abdollah; Abdi, Kamaleddin; Khayatiyan, Gholam-Reza

    2004-01-01

    The sol-gel technique was used to construct nickel pentacyanonitrosylferrate (NiPCNF) modified composite ceramic carbon electrodes (CCEs). This involves two steps: forming a CCE containing Ni powder and then immersing the electrode into a sodium pentacyanonitrosyl-ferrate solution (electroless deposition). The cyclic voltammograms of the resulting surface modified CCE under optimum conditions show a well-defined redox couple due to the [Ni II Fe III/II (CN) 5 NO] 0/-1 system. The electrochemical properties and stability of the modified electrode were investigated by cyclic voltammetry. The apparent electron transfer rate constant (k s ) and transfer coefficient (α) were determined by cyclic voltammetry being about 1.1 s -1 and 0.55, respectively. Sulfite has been chosen as a model to elucidate the electrocatalytic ability of NiPCNF-modified CCE prepared by one- or two-step sol-gel technique. The modified electrode showed excellent electrocatalytic activity toward the SO 3 2- electro oxidation in pH range 3-9 in comparison with CCE modified by homogeneous mixture of graphite powder, Ni(NO 3 ) 2 and Na 2 [Fe(CN) 5 NO] (one-step sol-gel technique). Sulfite was determined amperometrically at the surface of this modified electrode in pH 7. Under the optimized conditions the calibration curve is linear in the concentration range 2 μM to 2.0 mM. The detection limit (signal-to-noise is 3) and sensitivity are 0.5 μM and 13.5 nA/μM. The modified carbon ceramic electrode containing nickel pentacyanonitrosylferrate shows good repeatability, short response time, t (90%) 2 [Fe(CN) 5 NO] solution. The advantages of the SO 3 2- amperometrically detector based on the nickel pentacyanonitrosylferrate-doped CCE is high sensitivity, inherent stability at wide pH range, excellent catalytic activity and less expense and simplicity of preparation. This sensor can be used as amperometric detector in chromatographic instruments

  3. Preparation and Support of Part-Time Teachers in Higher Education.

    Science.gov (United States)

    Nicol, David J.

    2000-01-01

    Examines research on preparation and support of part-time faculty, analyzing four areas of support: institutional policies and practices, formal preparation programs, monitoring and evaluation systems, and formal and informal support measures in academic departments. Key processes and problems in each area are discussed, examining issues that must…

  4. Effect of preparation conditions on Nickel Zinc Ferrite nanoparticles: A comparison between sol–gel auto combustion and co-precipitation methods

    Directory of Open Access Journals (Sweden)

    Manju Kurian

    2016-09-01

    Full Text Available The experimental conditions used in the preparation of nano crystalline mixed ferrite materials play an important role in the particle size of the product. In the present work a comparison is made on sol–gel auto combustion methods and co-precipitation methods by preparing Nickel Zinc Ferrite (Ni0.5Zn0.5Fe2O4 nano particles. The prepared ferrite samples were calcined at different temperatures and characterized by using standard methods. X-ray diffraction analysis indicated the formation of single phase ferrite nanoparticles for samples calcined at 500 °C. The lattice parameter range of 8.32–8.49 Å confirmed the cubic spinel structure. Average crystallite size estimated from X-ray diffractogram was found to be between 17 and 40 nm. The IR spectra showed two main absorption bands, the high frequency band ν1 around 600 cm−1 and the low frequency band ν2 around 400 cm−1 arising from tetrahedral (A and octahedral (B interstitial sites in the spinel lattice. TEM pictures showed particles in the nanometric range confirming the XRD data. The studies revealed that the sol–gel auto combustion method was superior to the co-precipitation method for producing single phase nano particles with smaller crystallite size.

  5. Oxidation characteristics of porous-nickel prepared by powder metallurgy and cast-nickel at 1273 K in air for total oxidation time of 100 h.

    Science.gov (United States)

    Mohamed, Lamiaa Z; Ghanem, Wafaa A; El Kady, Omayma A; Lotfy, Mohamed M; Ahmed, Hafiz A; Elrefaie, Fawzi A

    2017-11-01

    The oxidation behavior of two types of inhomogeneous nickel was investigated in air at 1273 K for a total oxidation time of 100 h. The two types were porous sintered-nickel and microstructurally inhomogeneous cast-nickel. The porous-nickel samples were fabricated by compacting Ni powder followed by sintering in vacuum at 1473 K for 2 h. The oxidation kinetics of the samples was determined gravimetrically. The topography and the cross-section microstructure of each oxidized sample were observed using optical and scanning electron microscopy. X-ray diffractometry and X-ray energy dispersive analysis were used to determine the nature of the formed oxide phases. The kinetic results revealed that the porous-nickel samples had higher trend for irreproducibility. The average oxidation rate for porous- and cast-nickel samples was initially rapid, and then decreased gradually to become linear. Linear rate constants were 5.5 × 10 -8  g/cm 2  s and 3.4 × 10 -8  g/cm 2  s for the porous- and cast-nickel samples, respectively. Initially a single-porous non-adherent NiO layer was noticed on the porous- and cast-nickel samples. After a longer time of oxidation, a non-adherent duplex NiO scale was formed. The two layers of the duplex scales were different in color. NiO particles were observed in most of the pores of the porous-nickel samples. Finally, the linear oxidation kinetics and the formation of porous non-adherent duplex oxide scales on the inhomogeneous nickel substrates demonstrated that the addition of new layers of NiO occurred at the scale/metal interface due to the thermodynamically possible reaction between Ni and the molecular oxygen migrating inwardly.

  6. cobalt (ii), nickel (ii)

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. The manganese (II), cobalt (II), nickel (II) and copper (II) complexes of N, N' – bis(benzoin)ethylenediiminato have been prepared and characterized by infrared, elemental analysis, conductivity measurements and solubility. The potentiometric, and elemental analyses studies of the complexes revealed 1:1 ...

  7. Preparation of Pt–Ru bimetallic catalyst supported on carbon ...

    Indian Academy of Sciences (India)

    Unknown

    of carbon nanotube (Iijima 1991) was first based on the carbon-arc method, though the carbon nanotube prepared by this method are more graphitic, the low yield and rela- tively small length (< 1 m) make the production cost very high. The template synthesis method (Martin 1994) and catalytic production methods (Jose et ...

  8. Synthesis and characterization of Co3O4 prepared from atmospheric pressure acid leach liquors of nickel laterite ores

    Science.gov (United States)

    Meng, Long; Guo, Zhan-cheng; Qu, Jing-kui; Qi, Tao; Guo, Qiang; Hou, Gui-hua; Dong, Peng-yu; Xi, Xin-guo

    2018-01-01

    A chemical precipitation-thermal decomposition method was developed to synthesize Co3O4 nanoparticles using cobalt liquor obtained from the atmospheric pressure acid leaching process of nickel laterite ores. The effects of the precursor reaction temperature, the concentration of Co2+, and the calcination temperature on the specific surface area, morphology, and the electrochemical behavior of the obtained Co3O4 particles were investigated. The precursor basic cobaltous carbonate and cobaltosic oxide products were characterized and analyzed by Fourier transform infrared spectroscopy, thermogravimetric differential thermal analysis, X-ray diffraction, field-emission scanning electron microscopy, specific surface area analysis, and electrochemical analysis. The results indicate that the specific surface area of the Co3O4 particles with a diameter of 30 nm, which were obtained under the optimum conditions of a precursor reaction temperature of 30°C, 0.25 mol/L Co2+, and a calcination temperature of 350°C, was 48.89 m2/g. Electrodes fabricated using Co3O4 nanoparticles exhibited good electrochemical properties, with a specific capacitance of 216.3 F/g at a scan rate of 100 mV/s.

  9. Development and characterization of nickel catalysts supported in CeO2-ZrO2-Al2O3, CeO2-La2O3-Al2O3 e ZrO2-La2O3-Al2O3 matrixes evaluated for methane reforming reactions

    International Nuclear Information System (INIS)

    Abreu, Amanda Jordão de

    2012-01-01

    Nowadays, the methane reforming is large interest industrial for the take advantage of these gas in production the hydrogen and synthesis gas (syngas). Among in the reactions of methane stand of the reactions steam reforming and carbon dioxide reforming of methane. The main catalysts uses in the methane reforming is Ni/Al 2 O 3 . However, the supported-nickel catalyst is susceptible to the deactivation or the destruction by coke deposition. The carbon dissolves in the nickel crystallite and its diffuses through the nickel, leading for formation of the carbon whiskers, which results in fragmentation of the catalyst. Modification of such catalysts, like incorporation of suitable promoters, is desirable to achieve reduction of the methane hydrogenolysis and/or promotion of the carbon gasification. Catalysts 5%Ni/Al 2 O 3 supported on solid solutions formed by ZrO 2 -CeO 2 , La 2 O 3 and CeO 2 -ZrO 2 -La 2 O 3 were prepared, characterized and evaluated in reactions steam and carbon dioxide reforming and partial oxidation of methane with objective the value effect loading solution solid in support. The supports were prepared by co-precipitation method and catalysts were prepared by impregnation method and calcined at 500 deg C. The supports and catalysts were characterized by Nitrogen Adsorption, method -rays diffraction (XRD), X-rays dispersive spectroscopy (XDS), spectroscopy in the region of the ultraviolet and the visible (UV-vis NIR) to and temperature programmed reduction (TPR), Raman Spectroscopy, X-ray absorption spectroscopy and Thermogravimetric Analysis. After all the catalytic reactions check which the addition of solid solution is beneficial for Ni/Al 2 O 3 catalysts and the best catalysts are Ni/CeO 2 -La 2 O 3 -Al 2 O 3 . (author)

  10. Preparation of self-supporting carbon thin films

    CERN Document Server

    Lommel, B; Kindler, B; Klemm, J; Steiner, J

    2002-01-01

    For heavy-ion beam experiments, self-supporting carbon thin films are needed as targets, stripper foils and as backings (Nucl. Instr. and Meth. A 334 (1993) 69) for materials which cannot be produced self-supporting. Using resistance evaporation under high vacuum, self-supporting carbon foils with a thickness of 5 mu g/cm sup 2 and a diameter of 10 mm, a thickness of 10 mu g/cm sup 2 and a diameter of 50 mm up to a thickness of 50 mu g/cm sup 2 and a diameter of 300 mm can be obtained. Due to the energy impact of the heavy-ion beam, the amorphous carbon is restructured into textured graphite, as was found already by Dollinger et al. (Nucl. Instr. and Meth. A 303 (1991) 79). The discuss the production process as well as the change of the layer structure caused by the energy deposit.

  11. Electrodeposition of zinc--nickel alloys coatings

    Energy Technology Data Exchange (ETDEWEB)

    Dini, J W; Johnson, H R

    1977-10-01

    One possible substitute for cadmium in some applications is a zinc--nickel alloy deposit. Previous work by others showed that electrodeposited zinc--nickel coatings containing about 85 percent zinc and 15 percent nickel provided noticeably better corrosion resistance than pure zinc. Present work which supports this finding also shows that the corrosion resistance of the alloy deposit compares favorably with cadmium.

  12. Ordered mesoporous materials as model supports to study catalyst preparation

    NARCIS (Netherlands)

    Sietsma, J.R.A.

    2007-01-01

    Catalysts are indispensable to modern-day society because of their prominent role in petroleum refining, chemical processing, and the reduction of environmental pollution. The catalytically active component often consists of small metal (oxide) particles that are supported on a carrier such as

  13. Preparation of natural zeolitic supports for potential biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Tania; Ruiz-Salvador, A. Rabdel [Zeolites Engineering Laboratory, Institute of Materials Science and Technology (IMRE), University of Havana, Vedado, 10400 Havana (Cuba); Velazco, Lya [Electronic Department, Institute of Materials Science and Technology (IMRE), University of Havana, 10400 Havana (Cuba); Menorval, Louis Charles de [Institut Charles Gerhardt Montpellier, UMR 5253 CNRS-UM2, Equipe Agregats, Interfaces et Materiaux pour l' Energie, C.C. 1502, Place Eugene Bataillon, 34095 Montpellier cedex 5 (France); Rivera, Aramis, E-mail: aramis@fisica.uh.cu [Zeolites Engineering Laboratory, Institute of Materials Science and Technology (IMRE), University of Havana, Vedado, 10400 Havana (Cuba)

    2009-12-15

    Considering the biological properties reported for the purified natural clinoptilolite, NZ, we prepared K- and Li-enriched forms aimed at release matrices for biomedical applications. The raw material and the obtained solid samples were characterized by means of atomic absorption spectroscopy, X-ray diffraction, {sup 27}Al and {sup 29}Si MAS nuclear magnetic resonance, and nitrogen adsorption. The results demonstrated the structural stability of the materials after the different transformations applied. The chemical behavior of the samples in bi-distilled water and hydrochloric acid was studied by pH and conductivity measurements. A preliminary study related with the liberation of K and Li in aqueous medium was carried out by atomic absorption spectroscopy. The studies showed that the release of both ions from the solid samples is favored in HCl solutions, and that lithium is released faster than potassium in both dissolution media.

  14. Preparation of Al2O3 Supports for Thin Membrane Fabrication

    Directory of Open Access Journals (Sweden)

    Berna Topuz

    2017-12-01

    Full Text Available In this study, macroporous a-alumina supports were prepared by using vacuum-assisted filtration of α-Al2O3 suspensions with different particle size. The average particle sizes of the powders are 400 and 200 nm. The prepared supports had smooth and uniform surface microstructure and well suited for the fabrication of thin continuous membrane. The microstructure consists of a random close packing of 200 nm particles led to improved surface uniformity and roughness. ZnO spheres were prepared by homogeneous precipitation and added to the colloidal suspension to modify the support structure and increase the support flux. Structural parameters such as pore diameter and tortuosity of the prepared macroporous supports were estimated by using He, N2, CO2 permeance measurements. Slight pressure dependence in the permeance values indicated the contribution of viscous flow to the Knudsen flow. The supports prepared by alumina powder with a larger particle size exhibited He permeance of three times higher than that of prepared with a smaller particle size. The addition of ZnO resulted in the increase in He permeance value significantly for the support prepared by 400 nm particles in size. He permeance was in a range of 8.5-8.7x10-6 mol/(m2sPa which is very close to the desired value of 1x10-5 mol/(m2sPa.

  15. Electrophoretic self-assembly of expanded mesocarbon microbeads with attached nickel nanoparticles as a high-rate electrode for supercapacitors

    Science.gov (United States)

    Wu, Mao-Sung; Fu, Yan-Hao

    2014-03-01

    Expanded mesocarbon microbeads (EMCMBs) with graphene oxide (GO) sheets were prepared by expanding graphitized mesocarbon microbeads (MCMBs) using a simple solution-based oxidative process. EMCMB-supported nickel nanoparticles with an average size of 4.6 nm were fabricated by an electrophoretic deposition (EPD) method in the presence of nickel nitrate additive. Nickel ions were self-assembled on the fluffy GO sheets resulting in a more positively charged EMCMB particle for facilitating EPD and dispersion. After heat treatment at 300 °C, GO could be converted to graphene which could provide a conductive network for facilitating the transport of electrons. Well-dispersed nickel nanoparticles on graphene sheets could act as a redox center to allow storage of extra charge and a nanospacer to prevent the graphene sheets from restacking. The specific capacitance of EMCMB-supported nickel electrode could reach 491 F g-1, which is much higher than that of EMCMB electrode (43 F g-1) and bare nickel electrode (146 F g-1) at a discharge current of 5 A g-1. More importantly, the EMCMB-supported nickel electrode is capable of delivering a high specific capacitance of 440 F g-1 at a discharge current of 50 A g-1, and could pave the way towards high-rate supercapacitors.Expanded mesocarbon microbeads (EMCMBs) with graphene oxide (GO) sheets were prepared by expanding graphitized mesocarbon microbeads (MCMBs) using a simple solution-based oxidative process. EMCMB-supported nickel nanoparticles with an average size of 4.6 nm were fabricated by an electrophoretic deposition (EPD) method in the presence of nickel nitrate additive. Nickel ions were self-assembled on the fluffy GO sheets resulting in a more positively charged EMCMB particle for facilitating EPD and dispersion. After heat treatment at 300 °C, GO could be converted to graphene which could provide a conductive network for facilitating the transport of electrons. Well-dispersed nickel nanoparticles on graphene sheets

  16. The Study Of The Impact Of Surface Preparation Methods Of Inconel 625 And 718 Nickel-Base Alloys On Wettability By BNi-2 And BNi-3 Brazing Filler Metals

    Directory of Open Access Journals (Sweden)

    Lankiewicz K.

    2015-06-01

    Full Text Available The article discusses the impact of surface preparation method of Inconel 625 and 718 nickel-base alloys in the form of sheets on wettability of the surface. The results of the investigations of surface preparation method (such as nicro-blasting, nickel plating, etching, degreasing, abrasive blasting with grit 120 and 220 and manually grinding with grit 120 and 240 on spreading of BNi-2 and BNi-3 brazing filler metals, widely used in the aerospace industry in high temperature vacuum brazing processes, are presented. Technological parameters of vacuum brazing process are shown. The macro- and microscopic analysis have shown that nicro-blasting does not bring any benefits of wettability of the alloys investigated.

  17. The Study of the Impact of Surface Preparation Methods of Inconel 625 and 718 Nickel-Base Alloys on Wettability by BNi-2 and BNi-3 Brazing Filler Metals

    Directory of Open Access Journals (Sweden)

    Lankiewicz K.

    2015-04-01

    Full Text Available The article discusses the impact of surface preparation method of Inconel 625 and 718 nickel-base alloys in the form of sheets on wettability of the surface. The results of the investigations of surface preparation method (such as nicro-blasting, nickel plating, etching, degreasing, abrasive blasting with grit 120 and 220 and manually grinding with grit 120 and 240 on spreading of BNi-2 and BNi-3 brazing filler metals, widely used in the aerospace industry in high temperature vacuum brazing processes, are presented. Technological parameters of vacuum brazing process are shown. The macro- and microscopic analysis have shown that nicro-blasting does not bring any benefits of wettability of the alloys investigated.

  18. Two-stage reduction for the preparation of ferronickel alloy from nickel laterite ore with low Co and high MgO contents

    Science.gov (United States)

    Chen, Yong-qiang; Zhao, Hong-liang; Wang, Cheng-yan

    2017-05-01

    The preparation of ferronickel alloy from the nickel laterite ore with low Co and high MgO contents was studied by using a pre-reduction-smelting method. The effects of reduction time, calcination temperature, quantity of reductant and calcium oxide (CaO), and pellet diameter on the reduction ratio of Fe and on the pellet strength were investigated. The results show that, for a roasting temperature >800 °C, a roasting time >30 min, 1.5wt% added anthracite coal, 5wt% added CaO, and a pellet size of 10 mm, the reduction ratio of Fe exceeds 70% and the compressive strength of the pellets exceeds 10 kg per pellet. Reduction smelting experiments were performed by varying the smelting time, temperature, quantity of reductant and CaO, and reduction ratio of Fe in the pellets. Optimal conditions for the reduction smelting process are as follows: smelting time, 30-45 min; smelting temperature, 1550°C; quantity of reductant, 4wt%-5wt%; and quantity of CaO, 5wt%; leading to an Fe reduction ratio of 75% in the pellets. In addition, the mineral composition of the raw ore and that during the reduction process were investigated by process mineralogy.

  19. Influence of nickel substitution on crystal structure and magnetic properties of strontium ferrite preparation via sol-gel auto-combustion route

    Science.gov (United States)

    Roohani, Ebrahim; Arabi, Hadi; Sarhaddi, Reza

    2018-01-01

    In this research, SrFe12‑xNixO19 (x = 0 ‑ 1) hexagonal ferrites were prepared by sol-gel auto-combustion method. Effect of Ni substitution on structural, morphological and magnetic properties of nanoparticles was investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM), respectively. The XRD results confirmed that all samples with x ≤ 0.5 have single phase M-type strontium ferrite structure, whereas for the SrFe12‑xNixO19 samples with x > 0.5, the spinel NiFe2O4 phase has also appeared. The lattice parameters and crystallite sizes of the powders were concluded from the XRD data and Williamson-Hall method. Magnetic analyses showed that the coercivity of powders decreased from 5672 Oe to 639 Oe while the saturation magnetization increased from 74 emu/g to 81 emu/g with nickel substitution. The results of this study suggest that the strontium hexaferrites doped with Ni are suitable for applications in high density magnetic recording media as well as microwave devices because of their promising magnetic properties.

  20. Preparation of high purity nickel film from industrial effluent by the distribution of charge over microelectrodes using newly designed free electrolytic diffusion approach

    International Nuclear Information System (INIS)

    Ahmed, Sheikh Asrar; Qadir, Muhammad Abdul; Zafar, Muhammad Nadeem; Hussain, Ishtiaq; Tufail, Shahid; Rashid, Saima; Shah, Hamid Ali

    2008-01-01

    The present work deals with the development of a newly designed free electrolytic diffusion approach (the distribution of charge over microelectrodes) for the purification of metals and was successfully applied for the purification of nickel from the industrial effluent containing high proportion of nickel. Atomic absorption spectrophotometer (AAS) analyzed the purified nickel deposited on working microelectrodes. The results obtained show that the purity of nickel was enhanced from 95% to 99.9% with traces of copper etc. It was concluded that distribution of charge over the microcathodes at a rate of 50 cycles per second (cps) shows better results for the production of high purity (HP) nickel as compared to 25 cycles per second (cps)

  1. Preparation of high purity nickel film from industrial effluent by the distribution of charge over microelectrodes using newly designed free electrolytic diffusion approach

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Sheikh Asrar; Qadir, Muhammad Abdul [Institute of Chemistry, University of the Punjab, Lahore, 54590 (Pakistan); Zafar, Muhammad Nadeem [Institute of Chemistry, University of the Punjab, Lahore, 54590 (Pakistan)], E-mail: znadeempk@yahoo.com; Hussain, Ishtiaq [Institute of Chemistry, University of the Punjab, Lahore, 54590 (Pakistan); Tufail, Shahid [PCSIR Laboratories Complex, Feroz pur Road, Lahore (Pakistan); Rashid, Saima; Shah, Hamid Ali [Institute of Chemistry, University of the Punjab, Lahore, 54590 (Pakistan)

    2008-09-15

    The present work deals with the development of a newly designed free electrolytic diffusion approach (the distribution of charge over microelectrodes) for the purification of metals and was successfully applied for the purification of nickel from the industrial effluent containing high proportion of nickel. Atomic absorption spectrophotometer (AAS) analyzed the purified nickel deposited on working microelectrodes. The results obtained show that the purity of nickel was enhanced from 95% to 99.9% with traces of copper etc. It was concluded that distribution of charge over the microcathodes at a rate of 50 cycles per second (cps) shows better results for the production of high purity (HP) nickel as compared to 25 cycles per second (cps)

  2. Nickel allergy

    DEFF Research Database (Denmark)

    Fischer, L A; Johansen, J D; Menné, T

    2007-01-01

    BACKGROUND: The frequency of nickel allergy varies between different population groups. Exposure regulation has proven effective in decreasing the frequency. Experimental studies with other allergens have shown a significant relation between patch test reactivity and repeated open application test...... (ROAT) reactivity. OBJECTIVES: This study was aimed at determining the elicitation threshold in nickel-allergic individuals in a patch test and a ROAT, and comparing the threshold from these two test methods. METHODS: Twenty nickel-allergic persons were tested with a dilution series of 19 concentrations...... in a patch test and a dilution series of three concentrations in a ROAT, with duration of up to 21 days. Eighteen persons with no nickel allergy were included as control group for the ROAT. RESULTS: The predicted dose which will elicit a reaction in 10% of allergic individuals was calculated to be 0...

  3. Preparation of nickel oxide thin films at different annealing temperature by sol-gel spin coating method

    International Nuclear Information System (INIS)

    Abdullah, M. A. R.; Mamat, M. H.; Ismail, A. S.; Malek, M. F.; Alrokayan, Salman A. H.; Khan, Haseeb A.; Rusop, M.

    2016-01-01

    Preparation of NiO thin films at different annealing temperature by sol-gel method was conducted to synthesize the quality of the surface thin films. The effects of annealing temperature on the surface topology were systematically investigated. Our studies confirmed that the surface roughness of the thin films was increased whenever annealing temperature was increase. NiO thin films morphology structure analysis was confirmed by field emission scanning electron microscope. Surface roughness of the thin films was investigated by atomic force microscopy.

  4. Electrocatalysts with platinum, cobalt and nickel preparations by mechanical alloyed and CVD for the reaction of oxygen reduction

    International Nuclear Information System (INIS)

    Garcia C, M. A.

    2008-01-01

    In this research, the molecular oxygen reduction reaction (ORR) was investigated on electrocatalysts of Co, Ni, Pt and their alloys CoNi, PtCo, PtNi and PtCoNi by using H 2 SO 4 0.5 and KOH 0.5 M solutions as electrolytes. The electrocatalysts were synthesized by Mechanical Alloying (MA) and Chemical Vapor Deposition (CVD) processes. For MA, metallic powders were processed during 20 h of milling in a high energy SPEX 8000 mill. For CVD, a hot-wall reactor was utilized and Co, Ni and Pt acetilactetonates were used as precursors. Films were deposited at a total pressure of 1 torr and temperatures of 400-450 C. Electrocatalysts were characterized by X-Ray Diffraction (XRD). Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Energy Dispersive X-Ray Spectroscopy (EDS). Electrocatalysts prepared by mechanical alloying showed a homogeneously dispersed agglomeration of particles with nano metric size. Electrocatalysts obtained by CVD showed, in some cases, non uniform films, with particles of nano metric size, as well. The electrocatalytic performance was evaluated by using the Rotating Disk Electrode technique (RDE). Electrocatalysts prepared by MA showed higher activity than those obtained by CVD. All electrocatalysts were evaluated in alkaline media. Only electrocatalysts containing Pt were evaluated in acid media, because those materials with Co, Ni and their alloys showed instability in acidic media. Most electrocatalysts followed a mechanism for the ORR producing a certain proportion of H 2 O 2 . All electrocatalysts, exhibited a fair or good electrocatalytic activity in comparison with other similar reported materials. It was found that MA and CVD are appropriate processes to prepare electrocatalysts for the ORR with particles of nano metric size and performing with an acceptable catalytic activity. PtCoNi 70-23-7% by MA and PtCoNi-CVD electrocatalysts showed the highest activity in alkaline media, while in acidic electrolyte PtCoNi 70

  5. Preparation of TiO₂ supported Au–Pd and Cu–Pd by the combined ...

    Indian Academy of Sciences (India)

    TiO₂ supported Au–Pd and Cu–Pd catalysts were prepared by strong electrostatic adsorption (SEA) of Pd followed by electroless deposition (ED) of a second metal with incremental surface coverages of Au or Cu. High dispersion of small Pd particles on the Pd/TiO2 prepared by SEA led to the high amount of second metal ...

  6. Preparation of supported Au–Pd and Cu–Pd by the combined strong ...

    Indian Academy of Sciences (India)

    BOONTIDA PONGTHAWORNSAKUN

    2017-10-25

    Oct 25, 2017 ... Abstract. TiO2 supported Au–Pd and Cu–Pd catalysts were prepared by strong electrostatic adsorption (SEA) of Pd followed by electroless deposition (ED) of a second metal with incremental surface coverages of Au or. Cu. High dispersion of small Pd particles on the Pd/TiO2 prepared by SEA led to the ...

  7. Preparing Students with Disabilities in an Urban School for Success in Supported and Competitive Employment

    Science.gov (United States)

    Miller, Valerie S.

    2010-01-01

    In schools that serve students with varying disabilities, community-based education has become an important element in preparing students for competitive and supported employment. Because of the constant change in demographics and the overall competitiveness of the job market, it is essential that schools are prepared to find ways of infusing…

  8. Catalog of Existing Small Tools for Surface Preparation and Support Equipment for Blasters and Painters

    National Research Council Canada - National Science Library

    Peart, John; Unthank, H. D

    1977-01-01

    The objective of this project has been to provide supervisors of shipyard surface preparation and coating operators with a catalog of the small tools and support equipment used by blasters and painters...

  9. Nanoscale investigation of the interface situation of plated nickel and thermally formed nickel silicide for silicon solar cell metallization

    Science.gov (United States)

    Mondon, A.; Wang, D.; Zuschlag, A.; Bartsch, J.; Glatthaar, M.; Glunz, S. W.

    2014-12-01

    In the context of nickel silicide formation from plated nickel layers for solar cell metallization, there are several open questions regarding contact adhesion and electrical properties. Nanoscale characterization by transmission electron microscopy has been employed to support these investigations. Interfacial oxides and silicide phases were investigated on differently prepared samples by different analytical methods associated with transmission electron microscopy analysis. Processing variations included the pre-treatment of samples before nickel plating, the used plating solution and the thermal budget for the nickel-silicon solid-state reaction. It was shown that interface oxides of only few nm thickness on both silicon and nickel silicide are present on the samples, depending on the chosen process sequence, which have been shown to play an important role in adhesion of nickel on silicide in an earlier publication. From sample pretreatment variations, conclusions about the role of an interfacial oxide in silicide formation and its influence on phase formation were drawn. Such an oxide layer hinders silicide formation except for pinhole sites. This reduces the availability of Ni and causes a silicide with low Ni content to form. Without an interfacial oxide a continuous nickel silicide of greater depth, polycrystalline modification and expected phase according to thermal budget is formed. Information about the nature of silicide growth on typical solar cell surfaces could be obtained from silicide phase and geometric observations, which were supported by FIB tomography. The theory of isotropic NiSi growth and orientation dependent NiSi2 growth was derived. By this, a very well performing low-cost metallization for silicon solar cells has been brought an important step closer to industrial introduction.

  10. Medical student use of Facebook to support preparation for anatomy assessments.

    Science.gov (United States)

    Pickering, James D; Bickerdike, Suzanne R

    2017-06-01

    The use of Facebook to support students is an emerging area of educational research. This study explored how a Facebook Page could support Year 2 medical (MBChB) students in preparation for summative anatomy assessments and alleviate test anxiety. Overall, Facebook analytics revealed that in total 49 (19.8% of entire cohort) students posted a comment in preparation for either the first (33 students) or second (34) summative anatomy assessments. 18 students commented in preparation for both. In total, 155 comments were posted, with 83 for the first and 72 for the second. Of the 83 comments, 45 related to checking anatomical information, 30 were requiring assessment information and 8 wanted general course information. For the second assessment this was 52, 14 and 6, respectively. Student perceptions on usage, and impact on learning and assessment preparation were obtained via a five-point Likert-style questionnaire, with 119 students confirming they accessed the Page. Generally, students believed the Page was an effective way to support their learning, and provided information which supported their preparation with increases in perceived confidence and reductions in anxiety. There was no difference between gender, except for males who appeared to be significantly less likely to ask a question as they may be perceived to lack knowledge (P Facebook can play an important role in supporting students in preparation for anatomy assessments. Anat Sci Educ 10: 205-214. © 2016 American Association of Anatomists. © 2016 American Association of Anatomists.

  11. Tensile-Creep Test Specimen Preparation Practices of Surface Support Liners

    Science.gov (United States)

    Guner, Dogukan; Ozturk, Hasan

    2017-12-01

    Ground support has always been considered as a challenging issue in all underground operations. Many forms of support systems and supporting techniques are available in the mining/tunnelling industry. In the last two decades, a new polymer based material, Thin Spray-on Liner (TSL), has attained a place in the market as an alternative to the current areal ground support systems. Although TSL provides numerous merits and has different application purposes, the knowledge on mechanical properties and performance of this material is still limited. In laboratory studies, since tensile rupture is the most commonly observed failure mechanism in field applications, researchers have generally studied the tensile testing of TSLs with modification of American Society for Testing and Materials (ASTM) D-638 standards. For tensile creep testing, specimen preparation process also follows the ASTM standards. Two different specimen dimension types (Type I, Type IV) are widely preferred in TSL tensile testing that conform to the related standards. Moreover, molding and die cutting are commonly used specimen preparation techniques. In literature, there is a great variability of test results due to the difference in specimen preparation techniques and practices. In this study, a ductile TSL product was tested in order to investigate the effect of both specimen preparation techniques and specimen dimensions under 7-day curing time. As a result, ultimate tensile strength, tensile yield strength, tensile modulus, and elongation at break values were obtained for 4 different test series. It is concluded that Type IV specimens have higher strength values compared to Type I specimens and moulded specimens have lower results than that of prepared by using die cutter. Moreover, specimens prepared by molding techniques have scattered test results. Type IV specimens prepared by die cutter technique are suggested for preparation of tensile test and Type I specimens prepared by die cutter technique

  12. Growing a carbon nano-fiber layer on a monolith support; effect of nickel loading and growth conditions

    NARCIS (Netherlands)

    Jarah nabeel abdul kareem amin, N.A.K.A.; Jarrah, Nabeel A.; van Ommen, J.G.; Lefferts, Leonardus

    2004-01-01

    This work describes how a new, extremely porous, hairy layer of carbon nano-fibers (CNFs) can be prepared on the surface of porous inorganic bodies, e.g. wash-coated monoliths. CNFs were prepared catalytically by methane and ethene decomposition over a Ni catalyst. The influence of the Ni particle

  13. A comparative study of alumina-supported Ni catalysts prepared by photodeposition and impregnation methods on the catalytic ozonation of 2,4-dichlorophenoxyacetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, Julia L., E-mail: ozliliana@yahoo.com.mx [Lab. Ing. Química Ambiental. ESIQIE–Instituto Politécnico Nacional (Mexico); Valenzuela, Miguel A. [Lab.Catálisis y Materiales. ESIQIE–Instituto Politécnico Nacional. Zacatenco (Mexico); Tiznado, Hugo [Centro de Nanociencias y Nanotecnología. CNyN Universidad Nacional Autónoma de México (Mexico); Poznyak, Tatiana [Lab. Ing. Química Ambiental. ESIQIE–Instituto Politécnico Nacional (Mexico); Chairez, Isaac [Departamento de Bioprocesos, UPIBI- Instituto Politécnico Nacional (Mexico); Magallanes, Diana [Lab. Ing. Química Ambiental. ESIQIE–Instituto Politécnico Nacional (Mexico)

    2017-02-15

    The heterogeneous catalytic ozonation on unsupported and supported oxides has been successfully tested for the removal of several refractory compounds in aqueous solution. In this work, alumina-supported nickel catalysts prepared by photodeposition and impregnation methods were compared in the catalytic ozonation of 2,4-dichlorophenoxyacetic acid (2,4-D). The catalysts were characterized by high-resolution electron microscopy and X-ray photoelectron spectroscopy. The photochemical decomposition of Ni acetylacetonate to produce Ni(OH){sub 2}, NiO, and traces of Ni° deposited on alumina was achieved in the presence of benzophenone as a sensitizer. A similar surface composition was found with the impregnated catalyst after its reduction with hydrogen at 500 °C and exposed to ambient air. Results indicated a higher initial activity and maleic acid (byproduct) concentration with the photodeposited catalyst (1 wt% Ni) compared to the impregnated catalyst (3 wt% Ni). These findings suggest the use of the photodeposition method as a simple and reliable procedure for the preparation of supported metal oxide/metal catalysts under mild operating conditions.

  14. A comparative study of alumina-supported Ni catalysts prepared by photodeposition and impregnation methods on the catalytic ozonation of 2,4-dichlorophenoxyacetic acid

    International Nuclear Information System (INIS)

    Rodríguez, Julia L.; Valenzuela, Miguel A.; Tiznado, Hugo; Poznyak, Tatiana; Chairez, Isaac; Magallanes, Diana

    2017-01-01

    The heterogeneous catalytic ozonation on unsupported and supported oxides has been successfully tested for the removal of several refractory compounds in aqueous solution. In this work, alumina-supported nickel catalysts prepared by photodeposition and impregnation methods were compared in the catalytic ozonation of 2,4-dichlorophenoxyacetic acid (2,4-D). The catalysts were characterized by high-resolution electron microscopy and X-ray photoelectron spectroscopy. The photochemical decomposition of Ni acetylacetonate to produce Ni(OH) 2 , NiO, and traces of Ni° deposited on alumina was achieved in the presence of benzophenone as a sensitizer. A similar surface composition was found with the impregnated catalyst after its reduction with hydrogen at 500 °C and exposed to ambient air. Results indicated a higher initial activity and maleic acid (byproduct) concentration with the photodeposited catalyst (1 wt% Ni) compared to the impregnated catalyst (3 wt% Ni). These findings suggest the use of the photodeposition method as a simple and reliable procedure for the preparation of supported metal oxide/metal catalysts under mild operating conditions.

  15. Carbon-Nanotube-Supported Bio-Inspired Nickel Catalyst and Its Integration in Hybrid Hydrogen/Air Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gentil, Solène [Univ. Grenoble Alpes, CNRS, DCM UMR 5250, 38000 Grenoble France; Laboratoire de Chimie et Biologie des Métaux, Univ. Grenoble Alpes, CNRS UMR5249, CEA, 38000 Grenoble France; Lalaoui, Noémie [Univ. Grenoble Alpes, CNRS, DCM UMR 5250, 38000 Grenoble France; Dutta, Arnab [Pacific Northwest National Laboratory, Richland WA 99532 USA; Current address: Chemistry Department, IIT Gandhinagar, Gujarat 382355 India; Nedellec, Yannig [Univ. Grenoble Alpes, CNRS, DCM UMR 5250, 38000 Grenoble France; Cosnier, Serge [Univ. Grenoble Alpes, CNRS, DCM UMR 5250, 38000 Grenoble France; Shaw, Wendy J. [Pacific Northwest National Laboratory, Richland WA 99532 USA; Artero, Vincent [Laboratoire de Chimie et Biologie des Métaux, Univ. Grenoble Alpes, CNRS UMR5249, CEA, 38000 Grenoble France; Le Goff, Alan [Univ. Grenoble Alpes, CNRS, DCM UMR 5250, 38000 Grenoble France

    2017-01-12

    A biomimetic nickel bis-diphosphine complex incorporating the amino-acid arginine in the outer coordination sphere, was immobilized on modified single-wall carbon nanotubes (SWCNTs) through electrostatic interactions. The sur-face-confined catalyst is characterized by a reversible 2-electron/2-proton redox process at potentials close to the equibrium potential of the H+/H2 couple. Consequently, the functionalized redox nanomaterial exhibits reversible electrocatalytic activity for the H2/2H+ interconversion over a broad range of pH. This system exhibits catalytic bias, analogous to hydrogenases, resulting in high turnover frequencies at low overpotentials for electrocatalytic H2 oxida-tion between pH 0 and 7. This allowed integrating such bio-inspired nanomaterial together with a multicopper oxi-dase at the cathode side in a hybrid bioinspired/enzymatic hydrogen fuel cell. This device delivers ~2 mW cm–2 with an open-circuit voltage of 1.0 V at room temperature and pH 5, which sets a new efficiency record for a bio-related hydrogen fuel cell with base metal catalysts.

  16. Wet chemical synthesis of nickel supported on alumina catalysts; Sintese de catalisadores de niquel suportado em alumina por via umida

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Ranny Rodrigues; Costa, Talita Kenya Oliveira; Morais, Ana Carla da Fonseca Ferreira; Costa, Ana Cristina Figueiredo de Melo; Freitas, Normanda Lino de, E-mail: normanda@ufcg.edu.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2016-07-01

    Heterogenic catalysts are those found to be in a different phase on the reaction when compared to the reactants and products. Preferred when compared to homogeneous catalysts due to the easiness on which the separation is processed. The objective of this study is to obtain and characterize Alumina based catalysts impregnated with Nickel (Al{sub 2}O{sub 3}), by wet impregnation. The alumina was synthesized by combustion reaction. Before and after the impregnation the catalysts were characterized by X-ray diffraction (XRD), granulometric analysis, the textural analysis will be held by nitrogen adsorption (BET), energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). The results show a presence of a stable crystalline phase of Al2O3 in all the studied samples and after the impregnation the second phase formed was of NiO and NiAl{sub 2}O{sub 4}. The Al{sub 2}O{sub 3} e Ni/Al{sub 2}O{sub 3} catalysts resulted in clusters with a medium diameter of 18.9 and 14.2 μm, respectively. The catalysts show a medium-pore characteristic (medium pore diameter between 2 and 50 nm), the superficial area to Al{sub 2}O{sub 3} and Ni/Al{sub 2}O{sub 3} catalysts were 8.69 m{sup 2}/g and 5.56 m{sup 2}/g, respectively. (author)

  17. Carbon-Nanotube-Supported Bio-Inspired Nickel Catalyst and Its Integration in Hybrid Hydrogen/Air Fuel Cells.

    Science.gov (United States)

    Gentil, Solène; Lalaoui, Noémie; Dutta, Arnab; Nedellec, Yannig; Cosnier, Serge; Shaw, Wendy J; Artero, Vincent; Le Goff, Alan

    2017-02-06

    A biomimetic nickel bis-diphosphine complex incorporating the amino acid arginine in the outer coordination sphere was immobilized on modified carbon nanotubes (CNTs) through electrostatic interactions. The functionalized redox nanomaterial exhibits reversible electrocatalytic activity for the H 2 /2 H + interconversion from pH 0 to 9, with catalytic preference for H 2 oxidation at all pH values. The high activity of the complex over a wide pH range allows us to integrate this bio-inspired nanomaterial either in an enzymatic fuel cell together with a multicopper oxidase at the cathode, or in a proton exchange membrane fuel cell (PEMFC) using Pt/C at the cathode. The Ni-based PEMFC reaches 14 mW cm -2 , only six-times-less as compared to full-Pt conventional PEMFC. The Pt-free enzyme-based fuel cell delivers ≈2 mW cm -2 , a new efficiency record for a hydrogen biofuel cell with base metal catalysts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Mineral resource of the month: nickel

    Science.gov (United States)

    Kuck, Peter H.

    2006-01-01

    Together with chromium, nickel makes steel more resistant to corrosion. Stainless steel thus accounts for more than 65 percent of primary nickel consumption in the world. One of the more common grades of stainless steel is Type 304, which contains 18 to 20 percent chromium and 10.5 to 12 percent nickel. Owing to their high corrosion resistance, nickel-bearing stainless steels are widely used in the transportation sector, the energy sector, the food preparation and processing industry, the beverage industry, the pharmaceutical industry and the medical community.

  19. Nickel allergy and orthodontics.

    Science.gov (United States)

    Rahilly, G; Price, N

    2003-06-01

    Nickel is the most common metal to cause contact dermatitis in orthodontics. Nickel-containing metal alloys, such as nickel-titanium and stainless steel, are widely used in orthodontic appliances. Nickel-titanium alloys may have nickel content in excess of 50 per cent and can thus potentially release enough nickel in the oral environment to elicit manifestations of an allergic reaction. Stainless steel has a lower nickel content (8 per cent). However, because the nickel is bound in a crystal lattice it is not available to react. Stainless steel orthodontic components are therefore very unlikely to cause nickel hypersensitivity. This article discusses the diagnosis of nickel allergy in orthodontics and describes alternative products that are nickel free or have a very low nickel content, which would be appropriate to use in patients diagnosed with a nickel allergy.

  20. XPS analysis of supported catalysts prepared in water-in-oil microemulsion system

    International Nuclear Information System (INIS)

    Mohd Ambar Yarmo; Wong Hoi Jin; Tan Chew Khim; Anita Ramli; Shahidan Radiman

    2002-01-01

    Catalysts supported on γ-alumina prepared by water-in-oil microemulsion were studied by X-ray photoelectron spectroscopy for comparison with catalysts prepared by wet impregnation. Comparable shifts to higher binding energies indicated a metal-support interaction where metal obtained via microemulsion is very small in size and highly dispersed. The positive binding energy shifts could be explained from a net unit positive charge remaining on the cluster in the photoemission final state in addition to the metallic screening from a redistribution of states within the bands. (Author)

  1. Catalyst component interactions in nickel/alumina catalyst

    Directory of Open Access Journals (Sweden)

    Kiš Erne E.

    2007-01-01

    Full Text Available The influence of nickel loading (5; 10; 20 wt% Ni, temperature of heat treatment (400; 700; 1100°C and way of catalyst preparation on the catalyst component interactions (CCI in the impregnated, mechanical powder mixed and co-precipitated catalyst was investigated. For sample characterization, low temperature nitrogen adsorption (LTNA and X-ray diffraction (XRD were applied. Significant differences were revealed, concerning CCI in dependence of nickel loading, temperature of heat treatment and way of catalyst preparation. The obtained results show that the support metal oxide interactions (SMI in impregnated and co-precipitated catalysts are more intensive than in the mechanical powder mixed catalyst. The degree and intensity of CCI is expressed by the ratio of real and theoretical surface area of the catalyst. This ratio can be used for a quantitative estimation of CCI and it is generally applicable to all types of heterogeneous catalysts.

  2. Process for preparation of a solid-phase radioimmunoassay support and use thereof

    International Nuclear Information System (INIS)

    Meriadec, B.; Roubertie, P.

    1979-01-01

    A process is described for the preparation of a support useful in radioimmunoassay chromatographic columns. The process involves the preparation of a chromatographic gel capable of selectively retaining one or more components contained in an antigen-antibody-containing solution. The gel is bound to the appropriate antiserum, then freeze-dried, pulverized and compressed into a tablet. The tablet support swells upon contact with an antigen-antibody-containing solution to conform to the shape of the columns. An example of the application of this support in the radioimmunoassay of thyroid-stimulating hormone is described. This type of support is also particularly useful in second antibody solid phase radioimmunoassays since there is no limit to the size of the antigen to which this technology may be applied. (U.K.)

  3. Preparation of supported vanadium and molybdenum oxide catalysts using metal acetylacetonate complexes

    NARCIS (Netherlands)

    van Hengstum, A.J.; van Ommen, J.G.; Bosch, H.; Gellings, P.J.

    1983-01-01

    Supported vanadium and molybdenum oxide catalysts were prepared by reaction of the corresponding acetylacetonate complex in a non-aqueous solution with the surface hydroxyl groups of the carrier. Continuous or batch adsorption of the metal acetylacetonate from toluene, as well as wet impregnation

  4. Factors influencing the preparation, support and training of South African expatriates

    Directory of Open Access Journals (Sweden)

    A. J. Vogel

    2008-12-01

    Full Text Available Purpose: The purpose of this paper is to determine if the independent variables; location of an international assignment, the age of an expatriate, the duration of an assignment and the management level of an expatriate, influence the preparation, support and training that they require for an international assignment. Design/Methodology/Approach: This formal, empirical study was undertaken using an electronic questionnaire that was distributed to expatriates who were on an international assignment. Expatriates who were on an international assignment were thought to be in the best position to respond to their preparation, support and training needs. Findings: The research found that the preparation, support and training required by South African expatriates are not influenced by the location of an international assignment, the age of the expatriate, the duration of an international assignment or the management level of the expatriate. Implications: The findings highlight the fact that human resource managers of South African multinational enterprises should provide all their expatriates with the same preparation, support and training, as well as identifies five requirements that should be included in all South African expatriate policies.

  5. Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance

    International Nuclear Information System (INIS)

    Zhang, Shuna; Zhang, Shujuan; Song, Limin; Wu, Xiaoqing; Fang, Sheng

    2014-01-01

    Graphical abstract: Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance. - Highlights: • Three-dimensional Ni 2 P has been prepared using foam nickel as a template. • The microstructures interconnected and formed sponge-like porous networks. • Three-dimensional Ni 2 P shows superior hydrodesulfurization activity. - Abstract: Three-dimensional microstructured nickel phosphide (Ni 2 P) was fabricated by the reaction between foam nickel (Ni) and phosphorus red. The as-prepared Ni 2 P samples, as interconnected networks, maintained the original mesh structure of foamed nickel. The crystal structure and morphology of the as-synthesized Ni 2 P were characterized by X-ray diffraction, scanning electron microscopy, automatic mercury porosimetry and X-ray photoelectron spectroscopy. The SEM study showed adjacent hollow branches were mutually interconnected to form sponge-like networks. The investigation on pore structure provided detailed information for the hollow microstructures. The growth mechanism for the three-dimensionally structured Ni 2 P was postulated and discussed in detail. To investigate its catalytic properties, SiO 2 supported three-dimensional Ni 2 P was prepared successfully and evaluated for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). DBT molecules were mostly hydrogenated and then desulfurized by Ni 2 P/SiO 2

  6. Influence of supports on catalytic behavior of nickel catalysts in carbon dioxide reforming of toluene as a model compound of tar from biomass gasification.

    Science.gov (United States)

    Kong, Meng; Fei, Jinhua; Wang, Shuai; Lu, Wen; Zheng, Xiaoming

    2011-01-01

    A series of supported Ni catalysts including Ni/MgO, Ni/γ-Al2O3, Ni/α-Al2O3, Ni/SiO2 and Ni/ZrO2 was tested in CO2 reforming of toluene as a model compound of tar from biomass gasification in a fluidized bed reactor, and characterized by the means of temperature programmed reduction with hydrogen (H2-TPR), XRD, TEM and temperature programmed oxidation (TPO). Combining the characterization results with the performance tests, the activity of catalyst greatly depended on Ni particles size, and the stability was affected by the coke composition. Both of them (Ni particle size and coke composition) were closely related to the interaction between nickel and support which would determine the chemical environment where Ni inhabited. The best catalytic performance was observed on Ni/MgO due to the strong interaction between NiO and MgO via the formation of Ni-Mg-O solid solution, and the highest dispersion of Ni particle in the basic environment. Copyright © 2010 Elsevier Ltd. All rights reserved.

  7. ELECTRODEPOSITION OF NICKEL ON URANIUM

    Science.gov (United States)

    Gray, A.G.

    1958-08-26

    A method is described for preparing uranium objects prior to nickel electroplating. The process consiats in treating the surface of the uranium with molten ferric chloride hexahydrate, at a slightiy elevated temperature. This treatment etches the metal surface providing a structure suitable for the application of adherent electrodeposits and at the same time plates the surface with a thin protective film of iron.

  8. Supporting Geoscience Students at Two-Year Colleges: Career Preparation and Academic Success

    Science.gov (United States)

    McDaris, J. R.; Kirk, K. B.; Layou, K.; Macdonald, H.; Baer, E. M.; Blodgett, R. H.; Hodder, J.

    2013-12-01

    Two-year colleges play an important role in developing a competent and creative geoscience workforce, teaching science to pre-service K-12 teachers, producing earth-science literate citizens, and providing a foundation for broadening participation in the geosciences. The Supporting and Advancing Geoscience Education in Two-Year Colleges (SAGE 2YC) project has developed web resources for geoscience faculty on the preparation and support of students in two-year colleges (2YCs). Online resources developed from two topical workshops and several national, regional, and local workshops around the country focus on two main categories: Career Preparation and Workforce Development, and Supporting Student Success in Geoscience at Two-year Colleges. The Career Preparation and Workforce Development resources were developed to help faculty make the case that careers in the geosciences provide a range of possibilities for students and to support preparation for the geoscience workforce and for transfer to four-year programs as geoscience majors. Many two-year college students are unaware of geoscience career opportunities and these materials help illuminate possible futures for them. Resources include an overview of what geoscientists do; profiles of possible careers along with the preparation necessary to qualify for them; geoscience employer perspectives about jobs and the knowledge, skills, abilities and attitudes they are looking for in their employees; employment trends in sectors of the economy that employ geoscience professionals; examples of geotechnician workforce programs (e.g. Advanced Technological Education Centers, environmental technology programs, marine technician programs); and career resources available from professional societies. The website also provides information to support student recruitment into the geosciences and facilitate student transfer to geoscience programs at four- year colleges and universities, including sections on advising support before

  9. Preparation of silicon carbide-supported vanadium oxide and its application of removing NO by ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zi-Bo; Xu, Xu [Yangzhou University, College of Environmental Science and Engineering, Yangzhou, Jiangsu (China); Bai, Shu-Li [Wuyi University, College of Chemical and Environmental Engineering, Jiangmen, Guangdong (China); Guan, Yu-Jiang; Jiang, Sheng-Tao [Taizhou University, Environmental Engineering, Taizhou, Zhejiang (China)

    2017-03-15

    The aim of this work was to study the preparation of SiC-supported V{sub 2}O{sub 5} catalysts and the kinetics on selective catalytic reduction for NO with NH{sub 3} on the catalysts. Using incipient wetness impregnation methods, vanadium oxide was applied to silicon carbide to prepare a SiC-supported vanadium oxide. X-ray photoelectron spectroscopy analysis confirmed that V{sub 2}O{sub 5} existed in the prepared materials. Using the prepared materials as catalysts, selective catalytic reduction for NO by NH{sub 3} has been analyzed, and reaction kinetics on the catalysts was studied at 150-300 C. The obtained results showed that the reduction reaction on the catalysts is close to zero-order kinetics with respect to NH{sub 3}, first-order with respect to NO, and half-order to O{sub 2}. Apparent activation energy for the reduction reaction was found to be 38 kJ mol{sup -1}. The prepared materials are stable and reusable. (orig.)

  10. Effects of nickel on eosinophil survival.

    Science.gov (United States)

    Ishihara, Kenji; Goi, Yoshiaki; Hong, Jang Ja; Seyama, Toshio; Ohtsu, Hiroshi; Wada, Hiroshi; Ohuchi, Kazuo; Hirasawa, Noriyasu

    2009-01-01

    Accessories, watches, coins and other items containing metal sometimes cause contact dermatitis and metal allergy. Among metals, nickel in alloys is ionized by sweat on the surface of the skin and exhibits particularly marked irritancy and allergenicity. Although eosinophils play important roles in allergy, the effects of nickel on eosinophils have not been elucidated. Eosinophils were prepared from the peritoneal cavity in rats immunized with Ascaris suum extract. Purified rat eosinophils were incubated in the presence of various kinds of metals including nickel. The viability of eosinophils was analyzed using a flow cytometer. When rat eosinophils were incubated for 3 days in the presence of nickel chloride at 30-1,000 microM, the viability of eosinophils was decreased in a concentration-dependent manner. Nickel chloride at 300 muM significantly increased the percentage of annexin V+ PI- eosinophils. The population of annexin V+ PI- eosinophils was also increased by nickel sulfate, cobalt chloride and zinc sulfate. The binding of nickel ions to eosinophils was detected by flow cytometer. Nickel ions bind to eosinophils and decrease the viability of eosinophils through the induction of apoptosis. Nickel ions may exhibit activity which modifies the function of eosinophils in allergy. Copyright 2009 S. Karger AG, Basel.

  11. PROCESSING AND CHARACTERIZATION OF TUBULAR CERAMIC SUPPORT FOR MICROFILTRATION MEMBRANE PREPARED FROM PYROPHYLLITE CLAY

    Directory of Open Access Journals (Sweden)

    Abedallah Talidi

    2011-09-01

    Full Text Available Tubular macroporous support for ceramic microfiltration membranes were prepared by extrusion followed by sintering of the low cost pyrophyllite clay. Clay powders mixed with some organic additives can be extruded to form a porous tubular support. The average pore size of the membrane is observed to increase from 5 µm to 10.8 µm when sintering temperature increase from 900 °C to 1200 °C. However, with the increase in temperature from 900 °C to 1200 °C, the support porosity is reduced from 47% to 30% and flexural strength is increased from 4 MPa to 17 MPa. The fabricated macro-porous supports are expected to have potential applications in the pre-treatment and also can be used like support for membranes of ultra-filtration.

  12. Preparation and Support of Patients through the Transplant Process: Understanding the Recipients' Perspectives

    Directory of Open Access Journals (Sweden)

    Oliver Mauthner

    2012-01-01

    Full Text Available Preparation for heart transplant commonly includes booklets, instructional videos, personalized teaching sessions, and mentorship. This paper explores heart transplant recipients’ thoughts on their preparation and support through the transplant process. Twenty-five interviews were audio-/videotaped capturing voice and body language and transcribed verbatim. Coding addressed language, bodily gesture, volume, and tone in keeping with our visual methodology. Recipients reported that only someone who had a transplant truly understands the experience. As participants face illness and life-altering experiences, maintaining a positive attitude and hope is essential to coping well. Healthcare professionals provide ongoing care and reassurance about recipients’ medical status. Mentors, family members, and close friends play vital roles in supporting recipients. Participants reported that only heart transplant recipients understood the experience, the hope, and ultimately the suffering associated with living with another persons’ heart. Attention needs to be focused not solely on the use of teaching modalities, but also on the development of innovative support networks. This will promote patient and caregiver engagement in self-management. Enhancing clinicians’ knowledge of the existential aspects of transplantation will provide them with a nuanced understanding of the patients’ experience, which will ultimately enhance their ability to better prepare and support patients and their caregivers.

  13. Mechanical Properties of Electrolyte Jet Electrodeposited Nickel Foam

    Directory of Open Access Journals (Sweden)

    Jinsong Chen

    2013-07-01

    Full Text Available Principles of the preparation of nickel foam by electrolyte jet electrodeposition were introduced, Nickel foam samples with different porosity were fabricated. Effect of different porosity on microhardness and uniaxial tensile properties of nickel foam was discussed. The results show that the microhardness of nickel foam is 320~400 HV, lower than entitative metal clearly. The lower the porosity of nickel foam, the higher the microhardness is. During the process of uniaxial tensile, nickel foam is characterized by three distinct regions, e.g. elastic deforming region, plastic plateau region and densification region. The higher the porosity of nickel foam, the lower the plastic plateau and the poorer the strength of nickel foam, accordingly

  14. Evaluation of nickel and copper catalysts in biogas reforming for hydrogen production in SOFC

    International Nuclear Information System (INIS)

    Silva, Leonardo Alves; Martins, Andre Rosa; Rangel, Maria do Carmo

    2017-01-01

    The solid oxide fuel cells (SOFC) enable the efficient generation of clean energy, fitting the current requirements of the growing demand for electricity and for the environment preservation. When powered with biogas (from digesters of municipal wastes), the SOFCs also contribute to reduce the environmental impact of these wastes. The most suitable route to produce hydrogen inside SOFC from biogas is through dry reforming but the catalyst is easily deactivated by coke, because of the high amounts of carbon in the stream. A promising way to overcome this drawback is by adding a second metal to nickel-based catalysts. Aiming to obtain active, selective and stable catalysts for biogas dry reforming, solids based on nickel (15%) and copper (5%) supported on aluminum and magnesium oxide were studied in this work. Samples were prepared by impregnating the support with nickel and copper nitrate, followed by calcination at 500, 600 and 800 deg C. It was noted that all solids were made of nickel oxide, nickel aluminate and magnesium aluminate but no copper compound was found. The specific surface areas did not changed with calcination temperature but the nickel oxide average particles size increased. The solids reducibility decreased with increasing temperature. All catalysts were active in methane dry reforming, leading to similar conversions but different selectivities to hydrogen and different activities in water gas shift reaction (WGSR). This behavior was assigned to different interactions between nickel and copper, at different calcination temperatures. All catalysts were active in WGSR, decreasing the hydrogen to carbon monoxide molar ratio and producing water. The catalyst calcined at 500 deg C was the most promising one, leading to the highest hydrogen yield, besides the advantage of being produced at the lowest calcination temperature, requiring less energy in its preparation. (author)

  15. Evaluation of nickel and copper catalysts in biogas reforming for hydrogen production in SOFC

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Leonardo Alves; Martins, Andre Rosa; Rangel, Maria do Carmo, E-mail: mcarmov@ufba.br [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Grupo de Estudos em Cinetica e Catalise; Ballarini, Adriana; Maina, Silvia [Instituto de Investigaciones en Catalisis Y Petroquimica Ing. Jose Miguel Parera (INCAPE), Santa Fe (Argentina)

    2017-01-15

    The solid oxide fuel cells (SOFC) enable the efficient generation of clean energy, fitting the current requirements of the growing demand for electricity and for the environment preservation. When powered with biogas (from digesters of municipal wastes), the SOFCs also contribute to reduce the environmental impact of these wastes. The most suitable route to produce hydrogen inside SOFC from biogas is through dry reforming but the catalyst is easily deactivated by coke, because of the high amounts of carbon in the stream. A promising way to overcome this drawback is by adding a second metal to nickel-based catalysts. Aiming to obtain active, selective and stable catalysts for biogas dry reforming, solids based on nickel (15%) and copper (5%) supported on aluminum and magnesium oxide were studied in this work. Samples were prepared by impregnating the support with nickel and copper nitrate, followed by calcination at 500, 600 and 800 deg C. It was noted that all solids were made of nickel oxide, nickel aluminate and magnesium aluminate but no copper compound was found. The specific surface areas did not changed with calcination temperature but the nickel oxide average particles size increased. The solids reducibility decreased with increasing temperature. All catalysts were active in methane dry reforming, leading to similar conversions but different selectivities to hydrogen and different activities in water gas shift reaction (WGSR). This behavior was assigned to different interactions between nickel and copper, at different calcination temperatures. All catalysts were active in WGSR, decreasing the hydrogen to carbon monoxide molar ratio and producing water. The catalyst calcined at 500 deg C was the most promising one, leading to the highest hydrogen yield, besides the advantage of being produced at the lowest calcination temperature, requiring less energy in its preparation. (author)

  16. A green synthetic strategy of nickel hexacyanoferrate nanoparticals supported on the graphene substrate and its non-enzymatic amperometric sensing application

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Zhonghua, E-mail: xzh@nwnu.edu.cn [Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); He, Nan [Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Rao, Honghong [College of Chemistry and Chemical Engineering, Lanzhou City University, Lanzhou, 730070 (China); Hu, Chenxian; Wang, Xiaofen; Wang, Hui; Liu, Xiuhui [Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Lu, Xiaoquan, E-mail: luxq@nwnu.edu.cn [Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China)

    2017-02-28

    Highlights: • A sensitive non-enzymatic glucose sensor was explored by using a facile and green strategy. • Well dispersed and uniform NiHCF nanoparticles can be effectively produced by the introduction of electrochemical reduction graphene oxide films. • Metal hexacyanoferrate as a potential electron mediator was proposed and applied into non-enzymatic sensing. - Abstract: Rapid glucose detection is a key requirement for both diagnosis and treatment of diabetes. A facile and green strategy to achieve spherical-shaped nickel hexacyanoferrate (NiHCF) nanoparticals supported on electrochemical reduction graphene oxide by using electrochemical cyclic voltammetry is explored. As a sensing substrate, electrochemical reduction graphene oxide deposited on a glassy carbon electrode surface exhibited obvious positive effect on the electrodeposition of NiHCF nanoparticals with spherical structure and thus effectively improved the electrical conductivity and electrochemical sensing of the proposed amperometric sensor. Proof-concept experiments demonstrated that the proposed nanocomposites modified electrode exhibited excellent sensitivity toward glucose oxidation as well as with a satisfying detection limit of 0.11 μM. More importantly, we also explore that as a simple, green and facile method, electrochemical technology can be employed and provide a new strategy for developing GO and metal hexacyanoferrate based amperometric sensing platform toward glucose and other biomolecules.

  17. Controlled fabrication of multilayered 4-(pyrrole-1-yl) benzoate supported poly(3,4-ethylenedioxythiophene) linked hybrid films of Prussian blue type nickel hexacyanoferrate

    Energy Technology Data Exchange (ETDEWEB)

    Makowski, Oktawian; Kowalewska, Barbara; Szymanska, Dorota; Stroka, Jadwiga; Miecznikowski, Krzysztof; Palys, Barbara; Kulesza, Pawel J. [Department of Chemistry, University of Warsaw, Pasteura 1, PL-02-093 Warsaw (Poland); Malik, Marcin A. [Division of Chemistry, Department of Processing and Materials Engineering and Applied Physics, Czestochowa University of Technology, Al. Armii Krajowej 19, 42-201 Czestochowa (Poland)

    2007-12-20

    The ability of 4-(pyrrole-1-yl) benzoic acid (PyBA) to form monolayer-type carboxylate-derivatized ultra-thin organic films on solid electrode surfaces was explored here to attract coordinatively and immobilize Ni{sup 2+} ions at the electrode/electrolyte interface. In the next step, the system was exposed to Fe(CN){sub 6}{sup 3-} or Fe(CN){sub 6}{sup 4-} solution to form a robust nickel hexacyanoferrate (NiHCF) layer. By repeated and alternate treatments in solutions of PyBA, Ni{sup 2+} cations, and Fe(CN){sub 6}{sup 3-} or Fe(CN){sub 6}{sup 4-} anions, the amount of the material could be increased systematically in a controlled fashion to form three-dimensional multilayered NiHCF-based assemblies. The layer-by-layer method was also extended to the growth of hybrid conducting polymer stabilized NiHCF films in which the initial PyBA-anchored NiHCF layer (formed on glassy carbon) was subsequently exposed (a desired number of times) through alternate immersions to the monomer (3,4-ethylenedioxythiophene), Fe(CN){sub 6}{sup 3-} and Ni{sup 2+} solutions. During voltammetric potential cycling (electropolymerization) in the external supporting electrolyte solution, poly(3,4-ethylenedioxythiophene) or PEDOT linked NiHCF-based multilayered films were produced. They were characterized by good stability and high dynamics of charge transport. (author)

  18. A green synthetic strategy of nickel hexacyanoferrate nanoparticals supported on the graphene substrate and its non-enzymatic amperometric sensing application

    International Nuclear Information System (INIS)

    Xue, Zhonghua; He, Nan; Rao, Honghong; Hu, Chenxian; Wang, Xiaofen; Wang, Hui; Liu, Xiuhui; Lu, Xiaoquan

    2017-01-01

    Highlights: • A sensitive non-enzymatic glucose sensor was explored by using a facile and green strategy. • Well dispersed and uniform NiHCF nanoparticles can be effectively produced by the introduction of electrochemical reduction graphene oxide films. • Metal hexacyanoferrate as a potential electron mediator was proposed and applied into non-enzymatic sensing. - Abstract: Rapid glucose detection is a key requirement for both diagnosis and treatment of diabetes. A facile and green strategy to achieve spherical-shaped nickel hexacyanoferrate (NiHCF) nanoparticals supported on electrochemical reduction graphene oxide by using electrochemical cyclic voltammetry is explored. As a sensing substrate, electrochemical reduction graphene oxide deposited on a glassy carbon electrode surface exhibited obvious positive effect on the electrodeposition of NiHCF nanoparticals with spherical structure and thus effectively improved the electrical conductivity and electrochemical sensing of the proposed amperometric sensor. Proof-concept experiments demonstrated that the proposed nanocomposites modified electrode exhibited excellent sensitivity toward glucose oxidation as well as with a satisfying detection limit of 0.11 μM. More importantly, we also explore that as a simple, green and facile method, electrochemical technology can be employed and provide a new strategy for developing GO and metal hexacyanoferrate based amperometric sensing platform toward glucose and other biomolecules.

  19. Engineering one-dimensional and two-dimensional birnessite manganese dioxides on nickel foam-supported cobalt–aluminum layered double hydroxides for advanced binder-free supercapacitors

    KAUST Repository

    Hao, Xiaodong

    2014-11-19

    © The Royal Society of Chemistry. We report a facile decoration of the hierarchical nickel foam-supported CoAl layered double hydroxides (CoAl LDHs) with MnO2 nanowires and nanosheets by a chemical bath method and a hydrothermal approach for high-performance supercapacitors. We demonstrate that owing to the sophisticated configuration of binder-free LDH@MnO2 on the conductive Ni foam (NF), the designed NF/LDH@MnO2 nanowire composites exhibit a highly boosted specific capacitance of 1837.8 F g-1 at a current density of 1 A g-1, a good rate capability, and an excellent cycling stability (91.8% retention after 5000 cycles). By applying the hierarchical NF/LDH@MnO2 nanowires as the positive electrode and activated microwave exfoliated graphite oxide activated graphene as the negative electrode, the fabricated asymmetric supercapacitor produces an energy density of 34.2 Wh kg-1 with a maximum power density of 9 kW kg-1. Such strategies with controllable assembly capability could open up a new and facile avenue in fabricating advanced binder-free energy storage electrodes. This journal is

  20. Nanoscale investigation of the interface situation of plated nickel and thermally formed nickel silicide for silicon solar cell metallization

    Energy Technology Data Exchange (ETDEWEB)

    Mondon, A., E-mail: andrew.mondon@ise.fraunhofer.de [Fraunhofer ISE, Heidenhofst. 2, D-79110 Freiburg (Germany); Wang, D. [Karlsruhe Nano Micro Facility (KNMF), H.-von-Helmholz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Zuschlag, A. [Universität Konstanz FB Physik, Jacob-Burckhardt-Str. 27, D-78464 Konstanz (Germany); Bartsch, J.; Glatthaar, M.; Glunz, S.W. [Fraunhofer ISE, Heidenhofst. 2, D-79110 Freiburg (Germany)

    2014-12-30

    Highlights: • Adhesion of metallization of fully plated nickel–copper contacts on silicon solar cells can be achieved by formation of nickel silicide at the cost of degraded cell performance. • Understanding of silicide growth mechanisms and controlled growth may lead to high performance together with excellent adhesion. • Silicide formation is well known from CMOS production from PVD-Ni on flat surfaces. Yet the deposition methods and therefore layer characteristics and the surface topography are different for plated metallization. • TEM analysis is performed for differently processed samples. • A nickel silicide growth model is created for plated Ni on textured silicon solar cells. - Abstract: In the context of nickel silicide formation from plated nickel layers for solar cell metallization, there are several open questions regarding contact adhesion and electrical properties. Nanoscale characterization by transmission electron microscopy has been employed to support these investigations. Interfacial oxides and silicide phases were investigated on differently prepared samples by different analytical methods associated with transmission electron microscopy analysis. Processing variations included the pre-treatment of samples before nickel plating, the used plating solution and the thermal budget for the nickel–silicon solid-state reaction. It was shown that interface oxides of only few nm thickness on both silicon and nickel silicide are present on the samples, depending on the chosen process sequence, which have been shown to play an important role in adhesion of nickel on silicide in an earlier publication. From sample pretreatment variations, conclusions about the role of an interfacial oxide in silicide formation and its influence on phase formation were drawn. Such an oxide layer hinders silicide formation except for pinhole sites. This reduces the availability of Ni and causes a silicide with low Ni content to form. Without an interfacial oxide

  1. Preparation and reactions of polymer-supported 1-Alkoxycarbony la kylidenear soranes

    Energy Technology Data Exchange (ETDEWEB)

    Castells, J.; Lopez-Calahorra, F.; Yu, Z. [Departamet de Quimica Organica, Universidad de Barcelona, Barcelona (Spain)

    1994-12-31

    Ethoxycarbonylalkyldiphenylpolystyrylarsonium triflates are easily prepared by reaction of diphenylpolystyrylarsine with ethyl 2-trifloxyalkanoates. ``One-pot`` Wittin reactions of these polymer-supported arsonium salts with aromatic aldehydes take place satisfactorily in all cases affording good yields of the corresponding (E)-2alkyl-3-arylpropenoates. Two steps reactions, with isolation of the corresponding 1-ethoxycarbonylalkylidenediphenylpolystyrylarsoranes work well except in the case of ethoxycarbonyl ethylidenediphenylpolystyrylarsorane. 11 refs.

  2. Strategies to Support PGCE Mathematics and Science Students Preparing for Assignments at Masters Level

    OpenAIRE

    Tas, Maarten; Forsythe, Sue

    2010-01-01

    The main aim of this study was to analyse and evaluate the effectiveness of support strategies being put into place for students who need to write assignments at Masters Level. In preparation for writing a 5000 word assignment on an aspect of teaching Mathematics or Science, 57 Science and Mathematics PGCE students were asked to write a 500 word synopsis which included an introduction, description of the main focus, questions that the assignment would address and possible strategies for teach...

  3. Supported Zeolite Beta Layers via an Organic Template-Free Preparation Route

    Directory of Open Access Journals (Sweden)

    Stephanie Reuss

    2018-01-01

    Full Text Available Layers of high silica zeolites, synthesized with an organic structure directing agent (OSDA and grown onto porous support structures, frequently suffer from the thermal stress during the removal of OSDA via the calcination process. The different thermal expansion coefficients of the zeolite and the support material, especially when stainless steel is used as a support, causes enormous tension resulting in defect formation in the zeolite layer. However, the calcination is an easy procedure to decompose the OSDA in the pore system of the zeolite. Recently, methods to synthesize zeolite beta without the use of an organic structure directing agent have been described. In the present study, a seed-directed synthesis is used to prepare OSDA-free zeolite beta layers on stainless steel supports via an in situ preparation route. For the application as membrane, a porous stainless steel support has been chosen. The beta/stainless steel composites are characterized by X-ray diffraction (XRD and scanning electron microscopy (SEM. To prove its possible application as a membrane, the beta/stainless steel composites were also tested by single gas permeances of H2, He, CO2, N2, and CH4.

  4. Supported Zeolite Beta Layers via an Organic Template-Free Preparation Route.

    Science.gov (United States)

    Reuss, Stephanie; Sanwald, Dirk; Schülein, Marion; Schwieger, Wilhelm; Al-Thabaiti, Shaeel A; Mokhtar, Mohamed; Basahel, Sulaiman N

    2018-01-21

    Layers of high silica zeolites, synthesized with an organic structure directing agent (OSDA) and grown onto porous support structures, frequently suffer from the thermal stress during the removal of OSDA via the calcination process. The different thermal expansion coefficients of the zeolite and the support material, especially when stainless steel is used as a support, causes enormous tension resulting in defect formation in the zeolite layer. However, the calcination is an easy procedure to decompose the OSDA in the pore system of the zeolite. Recently, methods to synthesize zeolite beta without the use of an organic structure directing agent have been described. In the present study, a seed-directed synthesis is used to prepare OSDA-free zeolite beta layers on stainless steel supports via an in situ preparation route. For the application as membrane, a porous stainless steel support has been chosen. The beta/stainless steel composites are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). To prove its possible application as a membrane, the beta/stainless steel composites were also tested by single gas permeances of H₂, He, CO₂, N₂, and CH₄.

  5. Studies on Bis(Para Anisidine Acetylacetonato) Nickel (II) Complex ...

    African Journals Online (AJOL)

    Studies on Bis(Para Anisidine Acetylacetonato) Nickel (II) Complex. HN Aliyu, UL Bilyamin. Abstract. Schiff base was prepared from the reaction of para anisidine and acetylacetone. Bis(para anisidineacetylacetonato)nickel(II) complex was synthesized by the reaction of the prepared para anisidineacetylacetone ligand and ...

  6. Nickel-supported carbon nitride photocatalyst combined with organic dye for visible-light-driven hydrogen evolution from water.

    Science.gov (United States)

    Mori, Kohsuke; Itoh, Taiki; Kakudo, Hiroki; Iwamoto, Tomoyuki; Masui, Yoichi; Onaka, Makoto; Yamashita, Hiromi

    2015-10-07

    A noble-metal-free photocatalytic H2 production system consisting of a Ni-based catalyst, visible-light-responsive organic dye, and graphitic carbon nitride (g-C3N4) as a support has been developed. Characterization by means of XAFS revealed that the deposition of a trinuclear Ni precursor complex, Ni(NiL2)2Cl2 (L = β-mercaptoethylamine), on the g-C3N4 affords a monomeric Ni(ii) species involving β-mercaptoethylamine and aqua ligands in an octahedral coordination geometry. Such a Ni species acts as a hydrogen production site from an aqueous solution without an electron relay reagent by combining with thiazole orange (TO) as a photosensitizer. The emission of the attached TO at around 550 nm decreases with increasing loading amount of Ni catalyst, suggesting electron transfer from TO to the Ni catalyst via the g-C3N4 support. Leaching and agglomeration of the active Ni catalyst and TO are not observed during the photocatalytic reaction. Moreover, the use of highly porous carbon nitride (nanoporous carbon nitride; nanoC3N4) is proven to significantly enhance the photocatalytic activity because of the high surface area due to the unique porous structure as well as high absorption and emission properties of TO associated with nanoC3N4.

  7. Influence of coprecipitation and mechanical mixture methods on the characteristics of nickel oxide-alumina composites

    International Nuclear Information System (INIS)

    Cordeiro, G.L.; Yoshito, W.K.; Ussui, V.; Lima, N.B. de; Lazar, D.R.R.

    2014-01-01

    Alumina-supported nickel catalysts are currently used in the reforming process due to low cost and high activity for hydrogen production from alcohols. In this work, the effect of preparation methods on nickel oxide-alumina based materials has been investigated. Nickel content was fixed at 15 wt%. Ceramic powders were obtained by coprecipitation in ammonia medium and mechanical mixture. Coprecipitated materials were calcined in air at 750 deg C to obtain the corresponding oxides. Materials obtained by mechanical mixture were prepared by wet milling of nickel oxide and alumina powders, both synthesized by precipitation and calcination in air at 450 and 750 deg C, respectively. Powders were characterized by X-ray diffraction, nitrogen gas sorption by applying the BET method, laser diffraction, scanning electron microscopy, electrophoretic mobility measurements for zeta potential determination and infrared spectroscopy. The results showed that coprecipitation method allowed the production of mixed oxides with high surface area (232,7 ± 3,2 m 2 .g -1 ) and normal granulometric distribution while mechanical mixture led to the formation of materials constituted by gamma alumina and nickel oxide phases, with low surface area (136,2 ± 0,5 m 2 .g -1 ) and bimodal granulometric distribution. (author)

  8. Preparation and evaluation of doped ceria interlayer on supported stabilized zirconia electrolyte SOFCs by wet ceramic processes

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Tuong Lan; Honda, Takeo; Iimura, Youko; Kato, Ken; Neghisi, Akira; Nozaki, Ken; Tappero, Fabrizio; Kato, Tohru [Fuel Cell Group, Energy Electronics Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8568 (Japan); Kobayashi, Kenichi; Sasaki, Kazuya; Shirahama, Hiroshi; Dokiya, Masayuki [Graduate School of Environment and Information Sciences, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama, 240-8501 (Japan); Ota, Kenichiro [Department of Energy and Safety Engineering, Yokohama National University, 79-7 Tokiwadai, Hodogaya-ku, Yokohama, 240-8501 (Japan)

    2004-10-29

    We have fabricated anode-supported solid oxide fuel cells (SOFCs) for reduced temperature operation by wet ceramic processes. Nickel/yttria-stabilised ZrO{sub 2} (Ni-YSZ), nickel/scandia-stabilised ZrO{sub 2} (Ni-ScSZ) cermets, ScSZ, gadolinia-doped ceria (GDC), and strontium-doped LaCoO{sub 3} (LSCO) were used as materials for anode substrate, anode functional layer, electrolyte, interlayer, and cathode, respectively. The influences of firing temperature of GDC films to the characteristics of ScSZ/GDC interface were investigated in detail using XRD and AC impedance spectroscopy; 1200C was considered as the optimum firing temperature of GDC film on ScSZ electrolyte. By combining the ScSZ electrolyte film with GDC interlayer, we succeeded in preventing the solid-state reactions between ScSZ and LSCO. The anode-supported SOFCs with GDC interlayer fired at 1200C generated electricity successfully at reduced temperature. However, in the case of SOFCs, with whole functional layers cofired together at 1200C, the performances of the cell were badly affected by the contact between ScSZ and GDC films. Further investigation for matching the sintering behaviors of ScSZ and GDC green films are required to realize a cost-effective cofiring process for fabricating the anode-supported SOFCs employing CGO interlayer.

  9. Preparation

    Directory of Open Access Journals (Sweden)

    M.M. Dardir

    2014-03-01

    Full Text Available Some hexanamide-mono and di-linoleniate esters were prepared by the reaction of linolenic acid and hexanamide (derived from the reaction of hexanoic acid and diethanolamine. The chemical structure for the newly prepared hexanamide-mono and di-linoleniate esters were elucidated using elemental analysis, (FTIR, H 1NMR and chemical ionization mass spectra (CI/Ms spectroscopic techniques. The results of the spectroscopic analysis indicated that they were prepared through the right method and they have high purity. The new prepared esters have high biodegradability and lower toxicity (environmentally friendly so they were evaluated as a synthetic-based mud (ester-based mud for oil-well drilling fluids. The evaluation included study of the rheological properties, filtration and thermal properties of the ester based-muds formulated with the newly prepared esters compared to the reference commercial synthetic-based mud.

  10. Human exposure to nickel.

    Science.gov (United States)

    Grandjean, P

    1984-01-01

    In order of abundance in the earth's crust, nickel ranks as the 24th element and has been detected in different media in all parts of the biosphere. Thus, humans are constantly exposed to this ubiquitous element, though in variable amounts. The average natural nickel exposure from food in the past has probably been somewhat, but not much, below current levels. Nickel is a useful metal, particularly in various alloys, in batteries and in nickel-plating. Nickel compounds are used especially as catalysts and pigments. In nickel-producing or nickel-using industries, about 0.2% of the work force may be exposed to considerable amounts of airborne nickel. In addition, nickel release, e.g., into cutting oils, and skin contact with nickel-containing or nickel-plated tools and other items may add to an occupational nickel hazard. Occupational exposures may lead to the retention of 100 micrograms of nickel per day. Environmental nickel levels depend particularly on natural sources, pollution from nickel-manufacturing industries and airborne particles from combustion of fossil fuels. Absorption from atmospheric nickel pollution is of minor concern. Vegetables usually contain more nickel than do other food items; high levels have been found in legumes, spinach, lettuce and nuts. Certain products, such as baking powder and cocoa powder, have been found to contain excessive amounts of nickel, perhaps related to nickel leaching during the manufacturing process. Soft drinking-water and acid beverages may dissolve nickel from pipes and containers. Leaching or corrosion processes may contribute significantly to the oral nickel intake, occasionally up to 1 mg/day. Scattered studies indicate a highly variable dietary intake of nickel, but most averages are about 200-300 micrograms/day. In addition, skin contact to a multitude of metal objects may be of significance to the large number of individuals suffering from contact dermatitis and nickel allergy. Finally, nickel alloys are often

  11. Fuel cell testing of Pt–Ru catalysts supported on differently prepared and pretreated carbon nanotubes

    International Nuclear Information System (INIS)

    Tokarz, Wojciech; Lota, Grzegorz; Frackowiak, Elzbieta; Czerwiński, Andrzej; Piela, Piotr

    2013-01-01

    Proton-exchange membrane fuel cell (PEMFC) testing of Pt–Ru catalysts supported on differently prepared multiwall carbon nanotube (MCNT) supports was performed to elucidate the influence of the different supports on the operating characteristics of the catalysts under real direct methanol fuel cell (DMFC) anode and H 2 -PEMFC anode conditions. The MCNTs were either thin, entangled or thick, disentangled. Pretreatment of the MCNTs was also done and it was either high-temperature KOH etching or annealing (graphitization). The performance of the catalysts was compared against the performance of a commercial Pt–Ru catalyst supported on a high-surface-area carbon black. Among the different MCNT supports, the graphitized, entangled support offered the best performance in all tests, which was equal to the performance of the commercial catalyst, despite the MCNT catalyst layer was ca. 2.2 times thicker than the carbon black catalyst layer. Even for an MCNT catalyst layer, which was almost 7 times thicker than the carbon black catalyst layer, the transport limitations were not prohibitive. This confirmed the expected potential of nanotube supports for providing superior reactant transport properties of the PEMFC catalyst layers

  12. Highly efficient palladium nanoparticles decorated reduced graphene oxide sheets supported on nickel foam for hydrogen peroxide electroreduction

    Science.gov (United States)

    Song, Congying; Cao, Liu; Li, Biaopeng; Huang, Xiaomei; Ye, Ke; Zhu, Kai; Cao, Dianxue; Cheng, Kui; Wang, Guiling

    2017-12-01

    A current collector of reduced graphene oxide modified Ni foam (RN) is synthesized through a handy method of hydrothermal. The sheet-like reduced graphene oxide (rGO) wrapped around the skeleton of Ni foam establishes a unique structure of the current collector with large surface area as well as good electronic conductivity which make a positive effect on the promotion of electrochemical property. Pd is chosen as the catalyst and deposited on the RN substrate in a form of nanoparticle by potentiostatic electro-deposition. Characterization analysis including scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and inductive coupled plasma emission spectrometer (ICP) are conducted to investigate the morphology and structure of the final electrode of Pd nanoparticles decorated rGO supported on Ni foam (PRN). In 2 mol L-1 NaOH and 0.5 mol L-1 H2O2, a current density of 450 mA cm-2 is gained on the PRN electrode which is much larger than that on the electrode of Pd nanoparticles directly deposited on Ni foam (PN). An excellent stability of the PRN electrode is also concluded by the measurements revealing that this material can be potentially and widely applied to direct hydrogen peroxide fuel cell in the near future.

  13. Microleakage of cavit in varnish-lined, matrix-supported endodontic access preparations.

    Science.gov (United States)

    Iqbal, M K; Saad, N A

    1998-07-01

    The effect of the application of a matrix band and the use of cavity varnish on the microleakage of Cavit in endodontic access preparations was investigated. Sixty human upper premolars were divided into six groups of ten specimens each. Access cavities with proximal extensions were prepared and filled with 1, Cavit only; 2, Cavit after application of varnish; 3, Cavit with the use of a matrix band; 4, Cavit with a matrix band and varnish; 5, incremental deposition of Cavit with the use of a matrix band and varnish; and 6, gutta percha stopping. The specimens were placed in 2% methylene blue dye, thermocycled, and evaluated for both proximal and occlusal linear leakage. The experimental group in which Cavit was incrementally deposited in varnish-lined and matrix-supported cavities exhibited significantly (p < 0.05) less proximal microleakage than those groups in which cavities were filled without the application of both a matrix band and a cavity varnish.

  14. Picture book support for preparing children ahead of and during day surgery.

    Science.gov (United States)

    Nilsson, Elisabeth; Svensson, Gunnar; Frisman, Gunilla Hollman

    2016-10-07

    Aim To develop and evaluate the use of a specific picture book aiming to prepare children for anaesthesia and surgery. Methods An intervention comparing two different information methods before ear, nose and throat day surgery was performed. The intervention involved using a specific information sheet and a specific picture book. Parents (n=104) of children aged 2-12 years completed open-ended questions that were analysed with qualitative content analysis. They were divided into two groups: one group received routine information and one received routine information and the intervention. Findings The picture sheet and picture book were valuable aids to prepare small children for anaesthesia and surgery by explaining the procedures that would take place. The parents expressed that knowledge of the procedures made them and the child feel secure. Conclusion Peri-operative information through pictures supports children and their parents during day surgery and may be helpful in future healthcare visits.

  15. Recovery of Uranium from Seawater: Preparation and Development of Polymer-Supported Extractants

    Energy Technology Data Exchange (ETDEWEB)

    Spiro, Alexandratos [City Univ. (CUNY), NY (United States). Hunter College

    2013-12-01

    A new series of polymer-supported extractants is proposed for the removal and recovery of uranium from seawater. The objective is to produce polymers with improved stability, loading capacity, and sorption kinetics compared to what is found with amidoximes. The target ligands are diphosphonates and aminomethyldiphosphonates. Small molecule analogues, especially of aminomethyldiphos-phonates, have exceptionally high stability constants for the uranyl ion. The polymeric diphosphonates will have high affinities due to their ability to form six-membered rings with the uranyl ion while the aminomethyldiphosphonates may have yet higher affinities due to possible tridentate coordination and their greater acidity. A representative set of the polymers to be prepared are indicated.

  16. NICKEL PLATING PROCESS

    Science.gov (United States)

    Hoover, T.B.; Zava, T.E.

    1959-05-12

    A simplified process is presented for plating nickel by the vapor decomposition of nickel carbonyl. In a preferred form of the invention a solid surface is nickel plated by subjecting the surface to contact with a mixture containing by volume approximately 20% nickel carbonyl vapor, 2% hydrogen sulfide and .l% water vapor or 1% oxygen and the remainder carbon dioxide at room temperature until the desired thickness of nickel is obtained. The advantage of this composition over others is that the normally explosive nickel carbonyl is greatly stabilized.

  17. Comparison of Alterations in the Surface Topographies of HyFlex CM and HyFlex EDM Nickel-titanium Files after Root Canal Preparation: A Three-dimensional Optical Profilometry Study.

    Science.gov (United States)

    Uslu, Gülşah; Özyürek, Taha; Yılmaz, Koray

    2018-01-01

    The aims of the present study were to examine the surface topographies of intact HyFlex CM and HyFlex EDM nickel-titanium files and to compare alterations in the surface topographies of these files after root canal preparation of severely curved canals of molar teeth. Eight HyFlex CM (25/.08) and 8 HyFlex EDM (25/.08) files were included in the present study. In total, 64 severely curved canals of molar teeth, with curvature angles ranging between 50° and 70°, were prepared with HyFlex CM and EDM (n = 32 in each group). Quantitative and qualitative analyses of the files' surface deformation were performed by using three-dimensional optical profilometry before and after root canal preparation. The data were analyzed with the Student t test at the 5% significant level by using SPSS 21.0 software. In the HyFlex EDM group, the qualitative evaluation revealed the presence of cracks and microcavities after use of the file for root canal preparation, whereas only minor surface deformation was observed in the HyFlex CM group. The average roughness, root mean square roughness, and peak to valley height values of the HyFlex EDM group were significantly higher than those of the HyFlex CM group before and after root canal preparation (P EDM group was not statistically significant (P > .5). Within the limitations of the present study, the HyFlex CM files showed significantly higher surface alterations compared with the HyFlex EDM files after the preparation of severely curved root canals. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Healthy foods prepared at home: Diet and support as protective strategies during pregnancy for Hispanic women.

    Science.gov (United States)

    Hopkins, Allison L; Yeoman, Michelle; Ritenbaugh, Cheryl

    2018-01-01

    Birth outcomes tend to be better among Hispanics than among other ethnic groups, even when matched for poverty and education, and foreign-born Latinas compared to their US-born counterparts. These patterns suggest that sociocultural factors exhibited by recent immigrants have the potential to protect birth outcomes against the instability of minority and low socioeconomic status. To discover potential sociocultural factors, a pilot qualitative study was carried out in Tucson, Arizona, with 18 Hispanic mothers. The two most prevalent factors reported were (1) a healthy diet prepared at home from minimally processed ingredients, and (2) constant and comprehensive social support. When comparing responses related to diet by interview language preference, a proxy for acculturation, there was very little difference between participants who interviewed in Spanish and those who interviewed in English. This result may be explained by greater maternal social support and higher education levels among those who interviewed in English.

  19. Sustainable preparation of supported metal nanoparticles and their applications in catalysis.

    Science.gov (United States)

    Campelo, Juan M; Luna, Diego; Luque, Rafael; Marinas, José M; Romero, Antonio A

    2009-01-01

    Metal nanoparticles have attracted much attention over the last decade owing to their unique properties as compared to their bulk metal equivalents, including a large surface-to-volume ratio and tunable shapes. To control the properties of nanoparticles with particular respect to shape, size and dispersity is imperative, as these will determine the activity in the desired application. Supported metal nanoparticles are widely employed in catalysis. Recent advances in controlling the shape and size of nanoparticles have opened the possibility to optimise the particle geometry for enhanced catalytic activity, providing the optimum size and surface properties for specific applications. This Review describes the state of the art with respect to the preparation and use of supported metal nanoparticles in catalysis. The main groups of such nanoparticles (noble and transition metal nanoparticles) are highlighted and future prospects are discussed.

  20. Preparation and Properties of Nano Dy/TiO2 Films Supported on High Silica Fiber

    Directory of Open Access Journals (Sweden)

    HUANG Feng-ping

    2017-07-01

    Full Text Available In order to improve the photocatalytic degradation performance and stability of nano TiO2, Dy doped TiO2 supported on high silica glass fiber was prepared by microwave-sol method combined with dip-coating method. The samples were analyzed by XRD,SEM,PL,EDS,XPS and other equipments for phase composition of films,surface topography, surface elements and the stability of films. And the effects of pretreatment solution and coating method on the high-silica fiber film were investigated.In addition, the photocatalytic performance of the sample has been investigated by degrading methylene blue. The results show that the catalytic stability of Dy doping TiO2 nanofilms supported on high silica glass fiber can be improved and the degradation of methyl orange can reach 94% in 30min after 5 times of coating treatment.

  1. Th1 lymphokine production profiles of nickel-specific CD4+T-lymphocyte clones from nickel contact allergic and non-allergic individuals

    NARCIS (Netherlands)

    Kapsenberg, M. L.; Wierenga, E. A.; Stiekema, F. E.; Tiggelman, A. M.; Bos, J. D.

    1992-01-01

    Panels of nickel-specific T-lymphocyte clones (TLC) were prepared from nickel-allergic and non-allergic donors. TLC from both panels showed similar levels of expression of TCR alpha/beta, CD4, CD2, CD25, and CD29 and recognized nickel in association with class II HLA molecules with restriction

  2. [Nickel allergy and orthodontics].

    Science.gov (United States)

    Leenen, R L J; Kuijpers-Jagtman, A M; Jagtman, B A; Katsaros, C

    2009-04-01

    Nickel hypersensitivity is a common problem, especially among young females, with a prevalence of 5 to 10%, increasing to 30%. In comparison with the oral mucosa, skin is more sensitive to an allergic reaction. The oral mucosa is less sensitive to nickel due to the difference in anatomical structure and the presence of pellicle. Nickel is used in many orthodontic appliances. Due to corrosion nickel ions can be released into the oral cavity. The extent of the corrosion of the appliance depends on the pH, the composition of saliva and plaque, temperature and mechanical loading. In spite of the relatively high amount of nickel processed in orthodontic appliances nickel allergies are rare. In cases of nickel-hypersensitivity, nickel-free appliances should be used.

  3. Decorating multi-walled carbon nanotubes with nickel nanoparticles for selective hydrogenation of citral

    International Nuclear Information System (INIS)

    Tang Yuechao; Yang Dong; Qin Feng; Hu Jianhua; Wang Changchun; Xu Hualong

    2009-01-01

    The nanocomposites of multi-walled carbon nanotubes (MWNTs) decorated with nickel nanoparticles were conveniently prepared by a chemical reduction of nickel salt in the present of poly(acrylic acid) grafted MWNTs (PAA-g-MWNTs). Due to the strong interaction between Ni 2+ and -COOH, PAA-g-MWNTs became an excellent supporting material for Ni nanoparticles. The morphology and distribution of Ni nanoparticles on the surface of MWNTs were greatly influenced by the reduction temperatures, the experimental results also showed that the distribution of Ni nanoparticles was greatly improved while the MWNTs were modified by poly(acrylic acid) (PAA). The hydrogenation activity and selectivity of MWNTs decorated with Ni nanoparticles (Ni-MWNTs) for α, β-unsaturated aldehyde (citral) were also studied, and the experimental results showed that the citronellal, an important raw material for flavoring and perfumery industries, is the favorable product with a percentage as high as 86.9%, which is 7 times higher than that of catalyst by Ni-supported active carbon (Ni-AC). - Abstract: Nickel nanoparticles decorated multi-walled carbon nanotubes (Ni-MWNTs) nanocomposites were conveniently prepared by a chemical reduction of nickel salt in the present of poly(acrylic acid) grafted MWNTs (PAA-g-MWNTs). These nanocomposites possessed excellent catalytic activity and selectivity for hydrogenation of citral.

  4. Environmental and human toxicology of nickel - a review; Umwelt- und Humantoxikologie von Nickel - eine aktuelle Uebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Beyersmann, D. [Fachbereich Biologie und Chemie, Univ. Bremen (Germany)

    2006-07-01

    Nickel is a relatively rare element, and its concentrations in ambient air, soils and waters are very low. Higher burdens of nickel are found in nickel industries and their proximity. The human uptake of nickel from the ambient air is neglectably low, except in industrial exposures. The main fraction of human nickel uptake is from food, nearly 50% stems from vegetables. Only about 2% of the oral uptake of nickel are resorbed and distributed over all organs investigated. The uptake of nickel compounds through the skin generally is very low. However, chronic skin contact with nickel and nickel compounds causes a specific contact allergy. This disease was observed after occupational exposure but also frequently in the general population. The number of new cases has dropped considerably due to reinforced prevention. Epidemiological studies with workers of nickel smelting and refining plants have demonstrated increased risks of nose and lung cancer. Human data are supported by results from animal experiments which have shown that inhalation of various nickel compounds caused lung cancer. Furthermore, animal experiments have yielded evidence that oral and inhalative exposure to nickel compounds impair reproduction. National and international agencies have classified various nickel compounds as carcinogenic to humans. The unit cancer risk attributed to life-long inhalation of 1 {mu}g Ni/m{sup 3} air is estimated to be between 2 x 10{sup -4} and 7 x 10{sup -4}. Occupational exposure limits in Germany have been the Technical Guidance Values of 0.5 mg/m{sup 3} for nickel and weakly soluble nickel compounds and of 0.05 mg/m{sup 3} for inhalable droplets of soluble nickel salts. The German limit value for ambient immission is 0.015 mg Ni/m{sup 2}. d, and for emission 0,5 mg Ni/m{sup 3}. Limit values for nickel in air are to be taken not as safe thresholds but as guidance values for the delimitation of the cancer risk. (orig.)

  5. Urine nickel concentrations in nickel-exposed workers.

    Science.gov (United States)

    Bernacki, E J; Parsons, G E; Roy, B R; Mikac-Devic, M; Kennedy, C D; Sunderman, F W

    1978-01-01

    Electrothermal atomic absorption spectrometry was employed for analyses of nickel concentrations in urine samples from nickel-exposed workers in 10 occupational groups and from non-exposed workers in two control groups. Mean concentrations of nickel in urine were greatest in workers who were exposed to inhalation of aerosols of soluble nickel salts (e.g., workers in nickel plating operations and in an electrolytic nickel refinery). Less marked increases in urine nickel concentrations were found in groups of metal sprayers, nickel battery workers, bench mechanics and are welders. No significant increases in mean concentrations of nickel were found in urine samples from workers who performed grinding, buffing and polishing of nickel-containing alloys or workers in a coal gasification plant who employed Raney nickel as a hydrogenation catalyst. Measurements of nickel concentrations in urine are more sensitive and practical than measurements of serum nickel concentrations for evaluation of nickel exposures in industrial workers.

  6. Nanostructured Carbon Materials as Supports in the Preparation of Direct Methanol Fuel Cell Electrocatalysts

    Directory of Open Access Journals (Sweden)

    María Jesús Lázaro

    2013-08-01

    Full Text Available Different advanced nanostructured carbon materials, such as carbon nanocoils, carbon nanofibers, graphitized ordered mesoporous carbons and carbon xerogels, presenting interesting features such as high electrical conductivity and extensively developed porous structure were synthesized and used as supports in the preparation of electrocatalysts for direct methanol fuel cells (DMFCs. The main advantage of these supports is that their physical properties and surface chemistry can be tailored to adapt the carbonaceous material to the catalytic requirements. Moreover, all of them present a highly mesoporous structure, diminishing diffusion problems, and both graphitic character and surface area can be conveniently modified. In the present work, the influence of the particular features of each material on the catalytic activity and stability was analyzed. Results have been compared with those obtained for commercial catalysts supported on Vulcan XC-72R, Pt/C and PtRu/C (ETEK. Both a highly ordered graphitic and mesopore-enriched structure of these advanced nanostructured materials resulted in an improved electrochemical performance in comparison to the commercial catalysts assayed, both towards CO and alcohol oxidation.

  7. Performance improvement of pasted nickel electrodes with multi-wall carbon nanotubes for rechargeable nickel batteries

    International Nuclear Information System (INIS)

    Song, Q.S.; Aravindaraj, G.K.; Sultana, H.; Chan, S.L.I.

    2007-01-01

    Carbon nanotubes (CNTs) were employed as a functional additive to improve the electrochemical performance of pasted nickel-foam electrodes for rechargeable nickel-based batteries. The nickel electrodes were prepared with spherical β-Ni(OH) 2 powder as the active material and various amounts of CNTs as additives. Galvanostatic charge/discharge cycling tests showed that in comparison with the electrode without CNTs, the pasted nickel electrode with added CNTs exhibited better electrochemical properties in the chargeability, specific discharge capacity, active material utilization, discharge voltage, high-rate capability and cycling stability. Meanwhile, the CNT addition also lowered the packing density of Ni(OH) 2 particles in the three-dimensional porous nickel-foam substrate, which could lead to the decrease in the active material loading and discharge capacity of the electrode. Hence, the amount of CNTs added to Ni(OH) 2 should be optimized to obtain a high-performance nickel electrode, and an optimum amount of CNT addition was found to be 3 wt.%. The superior electrochemical performance of the nickel electrode with CNTs could be attributed to lower electrochemical impedance and less γ-NiOOH formed during charge/discharge cycling, as indicated by electrochemical impedance spectroscopy and X-ray diffraction analyses. Thus, it was an effective method to improve the electrochemical properties of pasted nickel electrodes by adding an appropriate amount of CNTs to spherical Ni(OH) 2 as the active material

  8. Analytical support for the preparation of bundle test QUENCH-10 on air ingress

    International Nuclear Information System (INIS)

    Birchley, J.; Haste, T.; Homann, C.; Hering, W.

    2005-07-01

    Bundle test QUENCH-10 is dedicated to study air ingress with subsequent water quench during a supposed accident in a spent fuel storage tank. It was proposed by AEKI, Budapest, Hungary and was performed on 21 July 2004 in the QUENCH facility at Forschungszentrum Karlsruhe. Preparation of the test is based on common analytical work at Forschungszentrum Karlsruhe and Paul Scherrer Institut, Villigen, Switzerland, mainly with the severe accident codes SCDAP/RELAP5 and MELCOR, to derive the protocol for the essential test phases, namely pre-oxidation, air ingress and quench phase. For issues that could not be tackled by this computational work, suggestions for the test conduct were made and applied during the test. Improvements of the experimental set-up and the test conduct were suggested and largely applied. In SCDAP/RELAP5, an error was found: for thick oxide scales, the output value of the oxide scale is sensibly underestimated. For the aims of the test preparation, its consequences could be taken into account. Together with the related computational and other analytical support by the engaged institutions the test is co-financed as test QUENCH-L1 by the European Community under the Euratom Fifth Framework Programme on Nuclear Fission Safety 1998 - 2002 (LACOMERA Project, contract No. FIR1-CT2002-40158). (orig.)

  9. Preparation and Characterization of ZnO Nanoparticles Supported on Amorphous SiO2

    Directory of Open Access Journals (Sweden)

    Ying Chen

    2017-08-01

    Full Text Available In order to reduce the primary particle size of zinc oxide (ZnO and eliminate the agglomeration phenomenon to form a monodisperse state, Zn2+ was loaded on the surface of amorphous silica (SiO2 by the hydrogen bond association between hydroxyl groups in the hydrothermal process. After calcining the precursors, dehydration condensation among hydroxyl groups occurred and ZnO nanoparticles supported on amorphous SiO2 (ZnO–SiO2 were prepared. Furthermore, the SEM and TEM observations showed that ZnO nanoparticles with a particle size of 3–8 nm were uniformly and dispersedly loaded on the surface of amorphous SiO2. Compared with pure ZnO, ZnO–SiO2 showed a much better antibacterial performance in the minimum inhibitory concentration (MIC test and the antibacterial properties of the paint adding ZnO–SiO2 composite.

  10. Preparation and Characterization of ZnO Nanoparticles Supported on Amorphous SiO₂.

    Science.gov (United States)

    Chen, Ying; Ding, Hao; Sun, Sijia

    2017-08-10

    In order to reduce the primary particle size of zinc oxide (ZnO) and eliminate the agglomeration phenomenon to form a monodisperse state, Zn 2+ was loaded on the surface of amorphous silica (SiO₂) by the hydrogen bond association between hydroxyl groups in the hydrothermal process. After calcining the precursors, dehydration condensation among hydroxyl groups occurred and ZnO nanoparticles supported on amorphous SiO₂ (ZnO-SiO₂) were prepared. Furthermore, the SEM and TEM observations showed that ZnO nanoparticles with a particle size of 3-8 nm were uniformly and dispersedly loaded on the surface of amorphous SiO₂. Compared with pure ZnO, ZnO-SiO₂ showed a much better antibacterial performance in the minimum inhibitory concentration (MIC) test and the antibacterial properties of the paint adding ZnO-SiO₂ composite.

  11. Delivering competence based training and capacity building to support sustainable uranium mining in less prepared areas

    International Nuclear Information System (INIS)

    Miko Dit Angoula, I.; Tulsidas, H.

    2014-01-01

    The IAEA project “Supporting sustainable uranium mining in less prepared areas” consists of a 3-year catalytic training and capacity building of a range of work packages/tasks targeted on technical, operational, regulatory, environmental, stakeholders and governance needs in uranium mining of African francophone uranium producer or potential producer countries. The project is externally funded by a contribution from the USA. The scope is defined by the identification and the delivery of training and further capacity-building measures to enhance national and regional preparedness in these francophone Member States for the conduct of sustainable uranium mining and production, with particular reference to environmental, social, economic issues and good governance within the context of fostering good, safe practices in the comprehensive extraction of all possible economic resources from the mining process.

  12. Preparation of Mesoporous Silica-Supported Palladium Catalysts for Biofuel Upgrade

    Directory of Open Access Journals (Sweden)

    Ling Fei

    2012-01-01

    Full Text Available We report the preparation of two hydrocracking catalysts Pd/CoMoO4/silica and Pd/CNTs/CoMoO4/silica (CNTs, carbon nanotubes. The structure, morphologies, composition, and thermal stability of catalysts were studied by X-ray diffraction (XRD, scanning electron microscopy (SEM, Raman spectroscopy, transmission electron microscopy (TEM, energy-dispersive X-ray (EDX, and thermogravimetric analysis (TGA. The catalyst activity was measured in a Parr reactor with camelina fatty acid methyl esters (FAMEs as the feed. The analysis shows that the palladium nanoparticles have been incorporated onto mesoporous silica in Pd/CoMoO4/silica or on the CNTs surface in Pd/CNTs/CoMoO4/silica catalysts. The different combinations of metals and supports have selective control cracking on heavy hydrocarbons.

  13. Removal of Congo red dye from aqueous solution with nickel-based metal-organic framework/graphene oxide composites prepared by ultrasonic wave-assisted ball milling.

    Science.gov (United States)

    Zhao, Shuaiqi; Chen, Ding; Wei, Fuhua; Chen, Nini; Liang, Zhao; Luo, Yun

    2017-11-01

    Metal-organic frameworks (MOFs) were successfully synthesized by ultrasonic wave-assisted ball milling. In the absence of organic solvent, the coupling effect of ultrasonic wave and mechanical force played an significant role in the synthesis of MOFs. Adsorption of Congo red (CR) was studied in view of adsorption kinetic, isotherm and thermodynamics. The adsorbent was carried out using X-ray diffraction (XRD), thermogravimetric analysis (TGA), N 2 adsorption-desorption isotherms, Raman spectroscopy and scanning electron microscope (SEM) methods. It was found that pseudo-second-order kinetic model and Freundlich adsorption isotherm matched well for the adsorption of CR onto nickel-based metal-organic framework/graphene oxide composites (Ni-MOF/GO). The results of the adsorption thermodynamics indicated that the adsorption process was a spontaneous and endothermic process. The adsorption capacity of graphene oxide/metal-organic frameworks (GO/MOFs) for CR reached 2489mg/g, much higher than previous reports. It was demonstrated that an increase in the number of active metal sites can dramatically improve the adsorption capacity of dye. A suitable dry temperature is beneficial for the improvement of adsorption capacity for dye. In this paper, the adsorption results indicated that ultrasonic wave-assisted ball milling has a good prospect for synthesis of MOFs with excellent adsorption performance. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The all-ceramic, inlay supported fixed partial denture. Part 1. Ceramic inlay preparation design: a literature review.

    Science.gov (United States)

    Thompson, M C; Thompson, K M; Swain, M

    2010-06-01

    The effect of cavity design is a controversial and underrated factor in the clinical success of ceramic inlays and inlay supported prosthesis. Many articles and studies have been conducted into the advantages and disadvantages of isolated aspects of preparation design, but lacking is a review of the most relevant papers which bring together a consensus on all the critical features. Hence, a review and analysis of cavity depth, width, preparation taper and internal line angles is warranted in our attempts to formulate preparation guidelines that will lead to clinically successful, all-ceramic inlay restorations and ceramic inlay supported prosthesis.

  15. Melt impregnation as a post processing treatment for performance enhancement in high capacity 3D microporous tin-copper-nickel intermetallic anode for Li-ion battery supported by electrodeposited nickel scaffold: A structural study

    Science.gov (United States)

    Sengupta, Srijan; Patra, Arghya; Mitra, Arijit; Jena, Sambedan; Das, Karabi; Majumder, Subhasish Basu; Das, Siddhartha

    2018-05-01

    This paper communicates stabilization of a Sn anode by impregnating it within the porous framework of a Ni-scaffold. The impregnation is carried out by electrodeposition Sn on Ni-foam followed by heating at 300 °C for 1 h. The Ni-foam was also electrodeposited on a Cu foil prior to deposition of Sn. The melting step leads to the formation of Nisbnd Sn and Cusbnd Sn intermetallics within pores of the Ni-scaffold. Snsbnd Cu/Ni intermetallics lithiate following the active-inactive strategy in which the inactive Cu/Ni buffers the volume expansion while Sn lithiates. Furthermore, this entire process takes place within Ni-scaffold which resists material pulverization and delamination and provide better electronic pathway for charge transfer. This active-inactive Sn:Snsbnd Cu/Ni intermetallic within a protected Ni-scaffold assembly results in 100th cycle discharge capacity of 587.9 mA h/g at a rate of 500 mA/g (0.5 C), and superior rate capability delivering 463 mAh/g at a rate of 2 A/g (2 C) while retaining structural integrity as compared to pure Sn electrodeposited (without heat-treatment) on the nickel scaffold.

  16. Nickel Nanowire@Porous NiCo2O4 Nanorods Arrays Grown on Nickel Foam as Efficient Pseudocapacitor Electrode

    Directory of Open Access Journals (Sweden)

    Houzhao Wan

    2017-12-01

    Full Text Available A three dimensional hierarchical nanostructure composed of nickel nanowires and porous NiCo2O4 nanorods arrays on the surface of nickel foam is successfully fabricated by a facile route. In this structure, the nickel nanowires are used as core materials to support high-pseudocapacitance NiCo2O4 nanorods and construct the well-defined NiCo2O4 nanorods shell/nickel nanowires core hierarchical structure on nickel foam. Benefiting from the participation of nickel nanowires, the nickel nanowire@NiCo2O4/Ni foam electrode shows a high areal specific capacitance (7.4 F cm−2 at 5 mA cm−2, excellent rate capability (88.04% retained at 100 mA cm−2, and good cycling stability (74.08% retained after 1,500 cycles. The superior electrochemical properties made it promising as electrode for supercapacitors.

  17. Preparation of composite hollow fiber membranes: co-extrusion of hydrophilic coatings onto porous hydrophobic support structures

    NARCIS (Netherlands)

    He, T.; Mulder, M.H.V.; Strathmann, H.; Wessling, Matthias

    2002-01-01

    Coating a layer onto a support membrane can serve as a means of surface functionalization of membranes. Frequently, this procedure is a two-step process. In this paper, we describe a concept of membrane preparation in which a coating layer forms in situ onto a support membrane in one step by a

  18. Effect of nickel oxide seed layers on annealed-amorphous titanium oxide thin films prepared using plasma-enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Cheng-Yang; Hong, Shao-Chyang [Institute of Electro-Optical and Materials Science, National Formosa University, Huwei, Yunlin, 63201, Taiwan (China); Hwang, Fu-Tsai [Department of Electro-Optical Engineering, National United University, Miao-Li, 36003, Taiwan (China); Lai, Li-Wen [ITRI South, Industrial Technology Research Institute, Liujia, Tainan, 73445, Taiwan (China); Lin, Tan-Wei [Institute of Electro-Optical and Materials Science, National Formosa University, Huwei, Yunlin, 63201, Taiwan (China); Liu, Day-Shan, E-mail: dsliu@sunws.nfu.edu.tw [Institute of Electro-Optical and Materials Science, National Formosa University, Huwei, Yunlin, 63201, Taiwan (China)

    2011-10-31

    The effect of a nickel oxide (NiO{sub x}) seed layer on the crystallization and photocatalytic activity of the sequentially plasma-enhanced chemical vapor deposited amorphous titanium oxide (TiO{sub x}) thin film processed by a post-annealing process was investigated. The evolution of the crystalline structures, chemical bond configurations, and surface/cross-sectional morphologies of the annealed TiO{sub x} films, with and without a NiO{sub x} seed layer, was examined using X-ray diffractometer, Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, atomic force microscopy, and field emission scanning electron microscope measurements. Thermo- and photo-induced hydrophilicity was determined by measuring the contact angle of water droplet. Photocatalytic activity after UV light irradiation was evaluated from the decolorization of a methylene blue solution. The crystallization temperature of the TiO{sub x} film, deposited on a NiO{sub x} seed layer, was found to be lower than that of a pure TiO{sub x} film, further improving the thermo- and photo-induced surface super-hydrophilicity. The TiO{sub x} film deposited onto the NiO{sub x} seed layer, resulting in significant cluster boundaries, showed a rough surface morphology and proved to alleviate the anatase crystal growth by increasing the post-annealing temperature, which yielded a more active surface area and prohibited the recombination of photogenerated electrons and holes. The photocatalytic activity of the NiO{sub x}/TiO{sub x} system with such a textured surface therefore was enhanced and optimized through an adequate post-annealing process.

  19. ATV Engineering Support Team Safety Console Preparation for the Johannes Kepler Mission

    Science.gov (United States)

    Chase, R.; Oliefka, L.

    2010-09-01

    This paper describes the improvements to be implemented in the Safety console position of the Engineering Support Team(EST) at the Automated Transfer Vehicle(ATV) Control Centre(ATV-CC) for the upcoming ATV Johannes Kepler mission. The ATV missions to the International Space Station are monitored and controlled from the ATV-CC in Toulouse, France. The commanding of ATV is performed by the Vehicle Engineering Team(VET) in the main control room under authority of the Flight Director. The EST performs a monitoring function in a room beside the main control room. One of the EST positions is the Safety console, which is staffed by safety engineers from ESA and the industrial prime contractor, Astrium. The function of the Safety console is to check whether the hazard controls are available throughout the mission as required by the Hazard Reports approved by the ISS Safety Review Panel. Safety console preparation activities were limited prior to the first ATV mission due to schedule constraints, and the safety engineers involved have been working to improve the readiness for ATV 2. The following steps have been taken or are in process, and will be described in this paper: • review of the implementation of Operations Control Agreement Documents(OCADs) that record the way operational hazard controls are performed to meet the needs of the Hazard Reports(typically in Flight Rules and Crew Procedures), • crosscheck of operational control needs and implementations with respect to ATV's first flight observations and post flight evaluations, with a view to identifying additional, obsolete or revised operational hazard controls, • participation in the Flight Rule review and update process carried out between missions, • participation in the assessment of anomalies observed during the first ATV mission, to ensure that any impacts are addressed in the ATV 2 safety documentation, • preparation of a Safety console handbook to provide lists of important safety aspects to be

  20. Electron transport and electrocatalytic properties of MWCNT/nickel nanocomposites: hydrazine and diethylaminoethanethiol as analytical probes

    CSIR Research Space (South Africa)

    Adekunle, AS

    2010-06-01

    Full Text Available This work describes the electron transport and electrocatalytic properties of chemically-synthesized nickel (Ni) and nickel oxide (NiO) nanoparticles supported on multi-walled carbon nanotubes (MWCNT) platforms. Successful modification...

  1. Creep in an electrodeposited nickel

    Czech Academy of Sciences Publication Activity Database

    Sklenička, Václav; Kuchařová, Květa; Kvapilová, Marie; Svoboda, Milan; Král, Petr; Vidrich, G.

    2013-01-01

    Roč. 48, č. 13 (2013), s. 4780-4788 ISSN 0022-2461 R&D Projects: GA ČR(CZ) GAP108/11/2260; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : nanocrystalline nickel * electrodeposited metals * nanocomposite * creep behavior * creep mechanisms Subject RIV: JG - Metallurgy Impact factor: 2.305, year: 2013

  2. Preparation of Modified Red Mud-Supported Fe Catalysts for Hydrogen Production by Catalytic Methane Decomposition

    Directory of Open Access Journals (Sweden)

    Quanrun Liu

    2017-01-01

    Full Text Available A modified red mud- (MRM- supported Fe catalyst (xFe/MRM was prepared using the homogeneous precipitation method and applied to methane decomposition to produce hydrogen. The TEM and SEM-EDX results suggested that the particle sizes of the xFe/MRM catalysts were much smaller than that of raw red mud (RM, and the active metal Fe was evenly distributed over the catalyst structure. Moreover, BET results indicated that the surface areas and pore volumes of the catalysts were significantly improved, and the pore sizes of xFe/MRM were distributed from 5 to 12 nm, which is typical for a mesoporous material. The activities of those catalysts for the catalytic decomposition of methane were studied at atmospheric pressure at a moderate temperature of 650°C; the results showed that the xFe/MRM catalysts were more active than RM and MRM. The methane conversion curves of xFe/MRM catalysts exhibited similar variation tendencies (three-step during the reaction despite different Fe contents, and the loading amount of Fe clearly affected the activity of the catalysts.

  3. The impact of preparation and support procedures for children with sickle cell disease undergoing MRI

    Energy Technology Data Exchange (ETDEWEB)

    Cejda, Katherine R. [St. Jude Children' s Research Hospital, Child Life Program, Memphis, TN (United States); Smeltzer, Matthew P. [St. Jude Children' s Research Hospital, Department of Biostatistics, Memphis, TN (United States); Hansbury, Eileen N. [Baylor International Hematology Center of Excellence and the Texas Children' s Center for Global Health, Houston, TX (United States); McCarville, Mary Elizabeth; Helton, Kathleen J. [St. Jude Children' s Research Hospital, Department of Radiological Sciences, Memphis, TN (United States); Hankins, Jane S. [St. Jude Children' s Research Hospital, Department of Hematology, Memphis, TN (United States)

    2012-10-15

    Children with sickle cell disease (SCD) often undergo MRI studies to assess brain injury or to quantify hepatic iron. MRI requires the child to lie motionless for 30-60 min, thus sedation/anesthesia might be used to facilitate successful completion of exams, but this poses additional risks for SCD patients. To improve children's ability to cope with MRI examinations and avoid sedation, our institution established preparation and support procedures (PSP). To investigate the impact of PSP in reducing the need for sedation during MRI exams among children with SCD. Data on successful completion of MRI testing were compared among 5- to 12-year-olds who underwent brain MRI or liver R2*MRI with or without receiving PSP. Seventy-one children with SCD (median age 9.85 years, range 5.57-12.99 years) underwent a brain MRI (n = 60) or liver R2*MRI (n = 11). Children who received PSP were more likely to complete an interpretable MRI exam than those who did not 30 of 33; 91% vs. 27 of 38; 71%, unadjusted OR = 4.1 (P = 0.04) and OR = 8.5 (P < 0.01) when adjusting for age. PSP can help young children with SCD complete clinically interpretable, nonsedated MRI exams, avoiding the risks of sedation/anesthesia. (orig.)

  4. Preparation of nickel and Ni{sub 3}Sn nanoparticles via extension of conventional citric acid and ethylene diamine tetraacetic acid mediated sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Li, Pingyun, E-mail: lpyljr@126.com; Deng, Guodong; Guo, Xiaode; Liu, Hongying; Jiang, Wei; Li, Fengsheng

    2016-05-25

    This work aims to extend the application field of sol–gel process from conventional oxides, carbides, sulfides to metallic nanocrystalline materials. Metallic ions were coordinated with chelating agents of citric acid (CA) and ethylene diamine tetraacetic acid (EDTA) in aqueous solution. Then the solutions were dried at 383 K, resulting in the formation of sol and gel. Heating treatments of dried gels were then carried out with protection of N{sub 2} atmosphere. Ni and Ni{sub 3}Sn alloy nanoparticles were obtained by this sol–gel method in the range of 623–823 K. The as-prepared Ni and Ni{sub 3}Sn alloy nanoparticles have average grain sizes of 15 and 30 nm, and have face-centred-cubic (fcc) crystalline phase. Our results provide new insight into the application of conventional sol–gel method. - Graphical abstract: Sol–gel method is conventionally applied to prepare oxides, carbides, and sulfides. In this work, the application field of sol–gel method is extended to metallic nanoparticles. By using citric acid (CA) and ethylene diamine tetraacetic acid (EDTA) mediated sol–gel method, metallic Ni (a and c) and Ni{sub 3}Sn (b and d) alloy nanoparticles can be prepared when the heating treatments are performed under N{sub 2} protecting atmosphere. The Ni and Ni{sub 3}Sn nanoparticles have face-centered-cubic (fcc) crystalline phase and ultrafine grain sizes. Diffraction peaks of (110) superstructure reflection plane of Ni{sub 3}Sn nanoparticles can also be observed in Figure b, which can be considered as direct evidence of formation of alloy crystalline phase by performing this sol–gel method. - Highlights: • Ni and Ni{sub 3}Sn alloy nanoparticles have been prepared by sol–gel processes. • Citric acid and ethylene diamine tetraacetic acid were applied as chelating agent. • Diffraction peak of superstructure reflection plane of Ni{sub 3}Sn was detected by XRD. • A novel strategy for preparation of alloy nanoparticles has been presented.

  5. Contaminated nickel scrap processing

    Energy Technology Data Exchange (ETDEWEB)

    Compere, A.L.; Griffith, W.L.; Hayden, H.W.; Johnson, J.S. Jr.; Wilson, D.F.

    1994-12-01

    The DOE will soon choose between treating contaminated nickel scrap as a legacy waste and developing high-volume nickel decontamination processes. In addition to reducing the volume of legacy wastes, a decontamination process could make 200,000 tons of this strategic metal available for domestic use. Contaminants in DOE nickel scrap include {sup 234}Th, {sup 234}Pa, {sup 137}Cs, {sup 239}Pu (trace), {sup 60}Co, U, {sup 99}Tc, and {sup 237}Np (trace). This report reviews several industrial-scale processes -- electrorefining, electrowinning, vapormetallurgy, and leaching -- used for the purification of nickel. Conventional nickel electrolysis processes are particularly attractive because they use side-stream purification of process solutions to improve the purity of nickel metal. Additionally, nickel purification by electrolysis is effective in a variety of electrolyte systems, including sulfate, chloride, and nitrate. Conventional electrorefining processes typically use a mixed electrolyte which includes sulfate, chloride, and borate. The use of an electrorefining or electrowinning system for scrap nickel recovery could be combined effectively with a variety of processes, including cementation, solvent extraction, ion exchange, complex-formation, and surface sorption, developed for uranium and transuranic purification. Selected processes were reviewed and evaluated for use in nickel side-stream purification. 80 refs.

  6. Contaminated nickel scrap processing

    International Nuclear Information System (INIS)

    Compere, A.L.; Griffith, W.L.; Hayden, H.W.; Johnson, J.S. Jr.; Wilson, D.F.

    1994-12-01

    The DOE will soon choose between treating contaminated nickel scrap as a legacy waste and developing high-volume nickel decontamination processes. In addition to reducing the volume of legacy wastes, a decontamination process could make 200,000 tons of this strategic metal available for domestic use. Contaminants in DOE nickel scrap include 234 Th, 234 Pa, 137 Cs, 239 Pu (trace), 60 Co, U, 99 Tc, and 237 Np (trace). This report reviews several industrial-scale processes -- electrorefining, electrowinning, vapormetallurgy, and leaching -- used for the purification of nickel. Conventional nickel electrolysis processes are particularly attractive because they use side-stream purification of process solutions to improve the purity of nickel metal. Additionally, nickel purification by electrolysis is effective in a variety of electrolyte systems, including sulfate, chloride, and nitrate. Conventional electrorefining processes typically use a mixed electrolyte which includes sulfate, chloride, and borate. The use of an electrorefining or electrowinning system for scrap nickel recovery could be combined effectively with a variety of processes, including cementation, solvent extraction, ion exchange, complex-formation, and surface sorption, developed for uranium and transuranic purification. Selected processes were reviewed and evaluated for use in nickel side-stream purification. 80 refs

  7. Tween 80 coated alumina: An alternative support for solid phase extraction of copper, nickel, cobalt and cadmium prior to flame atomic absorption spectrometric determination

    Directory of Open Access Journals (Sweden)

    S.Z. Mohammadi

    2016-11-01

    Full Text Available The potential of coated alumina as a sorbent for the simultaneous separation and preconcentration of copper, nickel, cobalt and cadmium ions has been investigated. Copper, nickel, cobalt and cadmium were adsorbed quantitatively on coated alumina in the pH of 6. The main factors such as pH, amount sorbent, sample and eluent flow rate, type and volume of elution solution and interfering ions on the sorption of metal ions have been investigated in detail. Under the optimum experimental conditions, the detection limits (3Sb of this method for Cu(II, Ni(II, Co(II and Cd(II ions were 0.4, 1.0, 1.2 and 0.2 ng mL−1 in the original solution, respectively. Seven replicate determinations of a mixture of 5.0 μg of Cu(II, Ni(II, Co(II and 1.0 μg of Cd(II ions in the original solution gave a mean absorbance of 0.093, 0.071, 0.066 and 0.049 with relative standard deviations 1.9%, 2.3%, 2.6% and 2.1%, respectively. The method has been applied for the determination of trace amounts of Cu(II, Ni(II, Co(II and Cd(II ions in tobacco, brewed tea and water samples with satisfactory results.

  8. Hydrogen vibrations in nickel hydride

    International Nuclear Information System (INIS)

    Eckert, J.; Daniels, W.B.; Kitchens, T.A.; Majkrzak, C.F.; Passell, L.

    1983-01-01

    This chapter examines nickel hydride which was prepared in a BeCu high pressure cell at room temperature by applying a hydrogen gas pressure of 7kbar to pellets pressed from fine nickel powder. It explains that the rate and degree of completion of the hydride formation was first checked by neutron diffraction using deuterium gas with the result that a deuterium to metal ratio of approximately 0.75 was reached. It points out that after desorption of the deuterium, the nickel sample was charged with hydrogen for the inelastic incoherent neutron scattering measurements. The chapter notes that measurements were performed with the Be filter technique at the Brookhaven High Flux Beam Reactor, and finds that the optic modes appear as a broad band in the phonon density of states from about 70 to 110 MeV with peaks at approximately 88 and 108 MeV. It finally discusses the effect of hydride formation on the acoustic phonon density of states

  9. Microwave assisted combustion synthesis and characterization of nickel ferrite nanoplatelets

    Directory of Open Access Journals (Sweden)

    M. Venkatesh

    2016-09-01

    Full Text Available Nickel ferrite nanoplatelets have been successfully synthesized by a simple microwave assisted combustion method using trisodium citrate as a fuel. The prepared sample was chemically and structurally characterized by different techniques and the magnetic behaviour was studied by field dependent magnetization measurement. The obtained results indicate that the prepared sample is phase pure nickel ferrite nanoplatelets having size in the range of 40–50 nm and it exhibits a soft ferromagnetic nature with saturation magnetization of 49 emu/g and coercivity of 167 G. Hence proposed method is a facile approach to obtain nickel ferrite nanoplatelets for broad spectrum of applications.

  10. Preparation of Environmental and Food Samples to Support the Heavy Metals Detection by Stripping Electrochemical

    International Nuclear Information System (INIS)

    Iswani S

    2002-01-01

    Preparation of environmental and food samples to support the heavy metals detection by stripping electrochemistry was done. The water samples taken directly from the ground water were acidified with 1 mL of HNO 3 acic suprapure was not digested, while the soils samples which have already dried in the oven at 105 o C, ware grinded and sieved through 150 μm, werte digested with HNO 3 acic suprapure in the digestion bomb at 150 o C for 3-4 hours. The mussels samples which have already freezed in the freezer were peeled, dried with N 2 liquid, grinded and dried again in the freeze drier at the pressure of ≅ 10 -2 mBar, and then were grinded again, weighted, digested with HNO 3 acic and HClO 4 suprapure in the digestion bomb at 150 o C for 3 hours. Food samples were homogenized by electric mixer, dried with freeze dried, homogenized again by using ZrO 2 ball mill, weighted, digested by HPA (high Pressure Asher). The heavy metals in the food samples solution of digestion product were detected by using Polarographic Analyzer EGandG of SWV and DPASV methods, while in the water, soils and the mussels solution were detected by using PDV 2000 and Polarograf E-505, DPASV method. The method validity were tested with SRM materials such as soil-5, soil-7, water W-4, and coppepoda. The heavy metals detection results in the water, soils, mussels, and food by electrochemical method were reported in this paper. (author)

  11. Preparation of carbon supported cobalt by electrostatic adsorption of [Co(NH[subscript 3])[subscript 6

    Energy Technology Data Exchange (ETDEWEB)

    D' Souza, L.; Regalbuto, J.R.; Miller, J.T. (BP Res. Cntr.); (UIC)

    2010-10-22

    Our previous paper [L. D'Souza, L. Jiao, J.R. Regalbuto, J.T. Miller, A.J. Kropf, J. Catal. 248 (2007) 165] presented the synthesis of cobalt catalysts on carbon (Timrex) and silica supports by strong electrostatic adsorption (SEA), using a cobalt hexaamine chloride ([Co(NH{sub 3}){sub 6}]Cl{sub 3}, CoHA) precursor. The CoHA undergoes reductive deammination in an uncontrolled manner in the presence of NaOH and adsorbs as Co{sub 3}O{sub 4} on carbon with broad size distribution. The present paper extends these studies toward the end of synthesizing well-dispersed Co oxide particles in a narrow size range on carbon supports using NH{sub 4}OH. Cobalt uptake versus pH was determined in NH{sub 4}OH and NaOH basified solutions over a number of carbons with varying point of zero charge (PZC). The resulting materials were characterized by ICP, powder XRD, XAS, TPR and STEM. CoHA in the presence of NH{sub 4}OH adsorbs as well dispersed as CoO, Co{sub 3}O{sub 4} and Co(OH){sub 4}{sup 2-} depending upon the pH of the adsorption solution. These phases were undetectable by powder XRD and STEM Z-contrast imaging, but could be identified by XAS. Additionally, non-adsorbed CoHA complexes underwent transformation to [Co(NH{sub 3}){sub 5}Cl]Cl{sub 2} at pH > 11 in solution. After calcinations of 250 C, particle sizes of Co{sub 3}O{sub 4} range from 20-50 {angstrom} from NH{sub 4}OH and 50-200 {angstrom} from NaOH. Maximum metal uptake was approximately 3.3 and 2.7 {micro}mol/m{sup 2} in presence of NaOH and NH{sub 4}OH, respectively. The SEA method of preparation was compared with incipient wetness impregnation (IWI) of Co(NO{sub 3}){sub 2}{sm_bullet}6H{sub 2}O; this method yields Co{sub 3}O{sub 4} particles after 250 C calcinations which are almost as small or in one case, smaller than the calcined SEA samples. Higher metal loadings can be achieved by the SEA method by successive adsorption steps with a little variation in particle size and distribution. However, the main

  12. [Mechanisms of nickel allergy].

    Science.gov (United States)

    Czarnobilska, Ewa; Obtułowicz, Krystyna; Wsołek, Katarzyna; Pietowska, Justyna; Spiewak, Radosław

    2007-01-01

    Nickel allergy constitutes a serious health problem of modern societies. Hypersensitivity to this metal is found in 13% adults and 8% children. Risk factors for nickel allergy are: female gender and early exposure to nickel, e.g. piercing. Various mechanisms of inducing nickel allergy are possible, which is also reflected in the different clinical pictures. Nickel can induce allergic reaction in 3 different ways: 1) it binds to carrier protein in the extracellular space and subsequently is processed and presented by antigen presenting cell (APC) in the context of MHC class II molecule, which activates CD4+ lymphocytes, 2) Ni penetrates into the cell where it binds to intracellular proteins, and subsequently it is presented in the context of MHC class I molecule, which activates CD8+ lymphocytes, 3) Ni can "bridge" MHC molecule together with the TCR receptor on lymphocyte without actually filling the antigen-binding site, which is in analogy to superantigens. Both Th2/Tc2 (IL-4, IL-5, IL-13) and Th1/ Tc1 (IFNgamma) take their part in the development of contact allergy to nickel. The trafficking of the effector cells to target organs (where the inflammatory reaction actually takes place) is controlled by homing antigens and chemokine receptors that are expressed on their surface. The accumulation of effector cells in a target organ can determine the symptoms of nickel allergy (the skin, mucosa etc.). The acquisition of nickel tolerance is possibly dependent on the IL-10 secretion by specific lymphocytes.

  13. [Nickel allergy and orthodontics

    NARCIS (Netherlands)

    Leenen, R.L.; Kuijpers-Jagtman, A.M.; Jagtman, B.A.; Katsaros, C.

    2009-01-01

    Nickel hypersensitivity is a common problem, especially among young females, with a prevalence of 5 to 10%, increasing to 30%. In comparison with the oral mucosa, skin is more sensitive to an allergic reaction. The oral mucosa is less sensitive to nickel due to the difference in anatomical structure

  14. A Predictive Study of Community College Faculty Perceptions of Student Academic Preparation, Work Ethics, and Institutional Support

    Science.gov (United States)

    Ibezim-Uche, Scholar

    2013-01-01

    Examined in this study were faculty perceptions of students who do not continue their college education. Also examined was how urban and rural community colleges faculty perceived academic preparation, work ethics, and institutional support as predictors of student success. In this predictive study of community college faculty, 36 faculty members…

  15. 76 FR 11811 - Environmental Document Prepared in Support of Oil and Gas Activities on the Alaska Outer...

    Science.gov (United States)

    2011-03-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management, Regulation and Enforcement Environmental Document Prepared in Support... availability to the public of the following environmental documents: Project name Location Project purpose...

  16. The Effects of Teacher Background, Teacher Preparation, and Support on Attitudes and Expectations of K-12 Urban Music Educators

    Science.gov (United States)

    Doyle, Jennifer L.

    2012-01-01

    The purpose of this study was to determine the effects of personal and professional background factors, teacher preparation, and support on urban music teacher disposition. Specifically, the study aimed to examine the status of K-12 urban music education; verify the psychometric appropriateness of the researcher-created survey instrument; analyze…

  17. Functionalized SBA-15 supported nickel (II)–oxime–imine catalysts for liquid phase oxidation of olefins under solvent-free conditions

    International Nuclear Information System (INIS)

    Paul, Luna; Banerjee, Biplab; Bhaumik, Asim; Ali, Mahammad

    2016-01-01

    A new oxime–imine functionalized highly ordered mesoporous SBA-15 (SBA-15-NH 2 -DAMO) has been synthesized via post-synthesis functionalization of SBA-15 with 3-aminopropyl-triethoxysilane followed by the Schiff base condensation with diacetylmonooxime, which was further reacted with Ni(ClO 4 ) 2 to yield the functionalized nickel catalyst SBA-15-NH 2 -DAMO-Ni. All the synthesized materials were thoroughly characterized using different characterization techniques. It was found that SBA-15-NH 2 -DAMO-Ni catalyzes the one-pot oxidation of olefins like styrene, cyclohexene, cyclooctene, 1-hexene and 1-octene to the corresponding benzaldehyde, cyclohexene-1-ol and cyclooctene-oxide, respectively under solvent-free conditions by using tert-butylhydroperoxide as oxidant. - Graphical abstract: A new well characterized oxime–imine functionalized highly ordered mesoporous SBA-15-NH 2 -DAMO-Ni complex catalyzes the one-pot oxidation of olefins under solvent free mild conditions.

  18. Electroless nickel plating on abs plastics from nickel chloride and nickel sulfate baths

    International Nuclear Information System (INIS)

    Inam-ul-haque; Ahmad, S.; Khan, A.

    2005-01-01

    Aqueous acid nickel chloride and alkaline nickel sulphate bath were studied for electroless nickel planting on acrylonitrile-butadiene-styrene (ABS) plastic. Before electroless nickel plating, specimens were etched, sensitized and activated. Effects of sodium hypophosphite and sodium citrate concentration on the electroless nickel plating thickness were discussed. Aqueous acid nickel chloride bath comprising, nickel chloride 10 g/L, sodium hypophosphite 40 g/L, sodium citrate 40g/L at pH 5.5, temperature 85 deg. C and density of 1 Be/ for thirty minutes gave best coating thickness in micrometer. It was found that acid nickel chloride bath had a greater stability, wide operating range and better coating thickness results than alkaline nickel sulphate bath. Acid nickel chloride bath gave better coating thickness than alkaline nickel sulfate bath

  19. Progress of the Application of Mesoporous Silica-Supported Heteropolyacids in Heterogeneous Catalysis and Preparation of Nanostructured Metal Oxides

    Directory of Open Access Journals (Sweden)

    Heyong He

    2010-01-01

    Full Text Available Mesoporous silica molecular sieves are a kind of unique catalyst support due to their large pore size and high surface area. Several methods have been developed to immobilize heteropolyacids (HPAs inside the channels of these mesoporous silicas. The mesoporous silica-supported HPA materials have been widely used as recyclable catalysts in heterogeneous systems. They have shown high catalytic activities and shape selectivities in some reactions, compared to the parent HPAs in homogeneous systems. This review summarizes recent progress in the field of mesoporous silica-supported HPAs applied in the heterogeneous catalysis area and preparation of nanostructured metal oxides using HPAs as precursors and mesoporous silicas as hard templates.

  20. Progress of the Application of Mesoporous Silica-Supported Heteropolyacids in Heterogeneous Catalysis and Preparation of Nanostructured Metal Oxides

    Science.gov (United States)

    Ren, Yuanhang; Yue, Bin; Gu, Min; He, Heyong

    2010-01-01

    Mesoporous silica molecular sieves are a kind of unique catalyst support due to their large pore size and high surface area. Several methods have been developed to immobilize heteropolyacids (HPAs) inside the channels of these mesoporous silicas. The mesoporous silica-supported HPA materials have been widely used as recyclable catalysts in heterogeneous systems. They have shown high catalytic activities and shape selectivities in some reactions, compared to the parent HPAs in homogeneous systems. This review summarizes recent progress in the field of mesoporous silica-supported HPAs applied in the heterogeneous catalysis area and preparation of nanostructured metal oxides using HPAs as precursors and mesoporous silicas as hard templates.

  1. Steric Effect on the Nucleophilic Reactivity of Nickel(III) Peroxo Complexes.

    Science.gov (United States)

    Kim, Jalee; Shin, Bongki; Kim, Hyunjeong; Lee, Junhyung; Kang, Joongoo; Yanagisawa, Sachiko; Ogura, Takashi; Masuda, Hideki; Ozawa, Tomohiro; Cho, Jaeheung

    2015-07-06

    A set of nickel(III) peroxo complexes bearing tetraazamacrocyclic ligands, [Ni(III)(TBDAP)(O2)](+) (TBDAP = N,N'-di-tert-butyl-2,11-diaza[3.3](2,6)pyridinophane) and [Ni(III)(CHDAP)(O2)](+) (CHDAP = N,N'-dicyclohexyl-2,11-diaza[3.3](2,6)pyridinophane), were prepared by reacting [Ni(II)(TBDAP)(NO3)(H2O)](+) and [Ni(II)(CHDAP)(NO3)](+), respectively, with H2O2 in the presence of triethylamine. The mononuclear nickel(III) peroxo complexes were fully characterized by various physicochemical methods, such as UV-vis, electrospray ionization mass spectrometry, resonance Raman, electron paramagnetic resonance, and X-ray analysis. The spectroscopic and structural characterization clearly shows that the NiO2 cores are almost identical where the peroxo ligand is bound in a side-on fashion. However, the different steric properties of the supporting ligands were confirmed by X-ray crystallography, where the CHDAP ligand gives enough space around the Ni core compared to the TBDAP ligand. The nickel(III) peroxo complexes showed reactivity in the oxidation of aldehydes. In the aldehyde deformylation reaction, the nucleophilic reactivity of the nickel(III) peroxo complexes was highly dependent on the steric properties of the macrocyclic ligands, with a reactivity order of [Ni(III)(TBDAP)(O2)](+) < [Ni(III)(CHDAP)(O2)](+). This result provides fundamental insight into the mechanism of the structure (steric)-reactivity relationship of metal peroxo intermediates.

  2. Preparation of Mesoporous SBA-16 Silica-Supported Biscinchona Alkaloid Ligand for the Asymmetric Dihydroxylation of Olefins

    Directory of Open Access Journals (Sweden)

    Shaheen M. Sarkar

    2014-01-01

    Full Text Available Optically active cinchona alkaloid was anchored onto mesoporous SBA-16 silica and the as-prepared complex was used as a heterogeneous chiral ligand of osmium tetraoxide for the asymmetric dihydroxylation of olefins. The prepared catalytic system provided 90–93% yield of vicinal diol with 92–99% enantioselectivity. The ordered mesoporous SBA-16 silica was found to be a valuable support for the cinchona alkaloid liganded osmium catalyst system which is frequently used in chemical industries and research laboratories for olefin functionalization.

  3. CuO/CeO2 catalysts prepared with different cerium supports for CO oxidation at low temperature

    International Nuclear Information System (INIS)

    Lu, Chi-Yuan; Chang, Wen-Chi; Wey, Ming-Yen

    2013-01-01

    The activity of a catalyst depends on the nature of its support, its active site, and its preparation method. This study aimed to employ various types of CeO 2 supports such as commercial CeO 2 and self-prepared CeO 2 for the preparation of copper catalysts. The CuO/CeO 2 catalysts were prepared using the polyol process and impregnation method. The catalysts were characterized using Brunauer–Emmett–Teller analysis, scanning electron microscopy, and X-ray analysis, and their catalytic activity for CO removal was evaluated in a microcatalytic reactor. The experimental results showed that the catalytic activity of the CuO/CeO 2 catalysts with different calcination temperatures decreased in the following order: 500 °C > 300 °C > 700 °C. Compared to the impregnation method, the polyol process generated well-dispersed metal particles over the support and showed higher CO removal efficiency with low activation energy. Compared to CuO/CeO 2 catalysts with commercial CeO 2 , those with CeO 2 that was self-prepared by pyrolysis had a large pore volume and good crystal structure of CeO 2 and showed good performance. The catalytic activity for CO removal was in the following order: CuO/CeO 2 -P (pyrolysis) > CuO/CeO 2 -C (commercial) > CuO/CeO 2 -D (deposition precipitation). CuO/CeO 2 -P catalysts showed good activity even at low temperature. The CuO/CeO 2 -P(300)-P-120 min catalyst was found to possess the good CO removal rate when the oxygen content was 6%, CO concentration was 500 ppm, catalyst weighed 1.0 g, pollutant gas velocity was 500 mL min −1 , SV was 3.7 × 10 4 h −1 , and reaction temperature was 150 °C. - Highlights: • CuO/CeO 2 catalysts were prepared using polyol and impregnation methods. • The supports of catalyst were self-prepared cerium oxide and commercial cerium oxide. • Pyrolysis and deposition precipitation methods were used for cerium preparation. • Catalytic activity of CuO/CeO 2 catalysts were evaluated by the removal of CO

  4. Low Nickel Diet in Dermatology

    OpenAIRE

    Sharma, Ashimav D

    2013-01-01

    Nickel is a ubiquitous trace element and the commonest cause of metal allergy among the people. Nickel allergy is a chronic, recurring problem; females are affected more commonly than males. Nickel allergy may develop at any age. Once developed, it tends to persist life-long. Nickel is present in most of the dietary items and food is considered to be a major source of nickel exposure for the general population. Nickel in the diet of a nickel-sensitive person can provoke dermatitis. Careful se...

  5. Low nickel diet in dermatology

    Directory of Open Access Journals (Sweden)

    Ashimav D Sharma

    2013-01-01

    Full Text Available Nickel is a ubiquitous trace element and the commonest cause of metal allergy among the people. Nickel allergy is a chronic, recurring problem; females are affected more commonly than males. Nickel allergy may develop at any age. Once developed, it tends to persist life-long. Nickel is present in most of the dietary items and food is considered to be a major source of nickel exposure for the general population. Nickel in the diet of a nickel-sensitive person can provoke dermatitis. Careful selection of food with relatively low nickel concentration can bring a reduction in the total dietary intake of nickel per day. This can influence the outcome of the disease and can benefit the nickel sensitive patient.

  6. Low nickel diet in dermatology.

    Science.gov (United States)

    Sharma, Ashimav D

    2013-05-01

    Nickel is a ubiquitous trace element and the commonest cause of metal allergy among the people. Nickel allergy is a chronic, recurring problem; females are affected more commonly than males. Nickel allergy may develop at any age. Once developed, it tends to persist life-long. Nickel is present in most of the dietary items and food is considered to be a major source of nickel exposure for the general population. Nickel in the diet of a nickel-sensitive person can provoke dermatitis. Careful selection of food with relatively low nickel concentration can bring a reduction in the total dietary intake of nickel per day. This can influence the outcome of the disease and can benefit the nickel sensitive patient.

  7. Issues in knowledge representation to support maintainability: A case study in scientific data preparation

    Science.gov (United States)

    Chien, Steve; Kandt, R. Kirk; Roden, Joseph; Burleigh, Scott; King, Todd; Joy, Steve

    1992-01-01

    Scientific data preparation is the process of extracting usable scientific data from raw instrument data. This task involves noise detection (and subsequent noise classification and flagging or removal), extracting data from compressed forms, and construction of derivative or aggregate data (e.g. spectral densities or running averages). A software system called PIPE provides intelligent assistance to users developing scientific data preparation plans using a programming language called Master Plumber. PIPE provides this assistance capability by using a process description to create a dependency model of the scientific data preparation plan. This dependency model can then be used to verify syntactic and semantic constraints on processing steps to perform limited plan validation. PIPE also provides capabilities for using this model to assist in debugging faulty data preparation plans. In this case, the process model is used to focus the developer's attention upon those processing steps and data elements that were used in computing the faulty output values. Finally, the dependency model of a plan can be used to perform plan optimization and runtime estimation. These capabilities allow scientists to spend less time developing data preparation procedures and more time on scientific analysis tasks. Because the scientific data processing modules (called fittings) evolve to match scientists' needs, issues regarding maintainability are of prime importance in PIPE. This paper describes the PIPE system and describes how issues in maintainability affected the knowledge representation used in PIPE to capture knowledge about the behavior of fittings.

  8. Nickel Particles Selectively Confined in the Mesoporous Channels of SBA-15 Yielding a Very Stable Catalyst for DRM Reaction.

    Science.gov (United States)

    Rodriguez-Gomez, Alberto; Pereñiguez, Rosa; Caballero, Alfonso

    2018-01-18

    A series of four Ni catalysts supported on SBA-15 and on a high SiO 2 surface area have been prepared by modified impregnation (ImU) and deposition-precipitation (DP) methods. The catalysts have been extensively characterized, including in situ XAS (bulk sensitive) and XPS (surface sensitive) techniques, and their catalytic activities evaluated in the dry reforming reaction of methane (DRM). The combined use of XPS and XAS has allowed us to determine the location of nickel particles on each catalyst after reduction at high temperature (750 °C). Both Ni/SiO 2 -DP and Ni/SBA-15-DP catalysts yield well-dispersed and homogeneous metallic phases mainly located in the mesoporosity of both supports. On the contrary, the Ni/SiO 2 -ImU and Ni/SBA-15-ImU catalysts present a bimodal distribution of the reduced nickel phase, with nickel metallic particles located out and into the mesoporous structure of SiO 2 or the SBA-15 channels. The Ni/SBA-15-DP catalyst was found the most stable and performing system, with a very low level of carbon deposition, about an order of magnitude lower than the equivalent ImU catalyst. This outstanding performance comes from the confinement of small and homogeneous nickel particles in the mesoporous channels of SBA-15, which, in strong interaction with the support, are resistant to sintering and coke deposition during the demanding reaction conditions of DRM.

  9. Restricted access materials and large particle supports for on-line sample preparation: an attractive approach for biological fluids analysis.

    Science.gov (United States)

    Souverain, S; Rudaz, S; Veuthey, J-L

    2004-03-05

    An analytical process generally involves four main steps: (1) sample preparation; (2) analytical separation; (3) detection; and (4) data handling. In the bioanalytical field, sample preparation is often considered as the time-limiting step. Indeed, the extraction techniques commonly used for biological matrices such as liquid-liquid extraction (LLE) and solid-phase extraction (SPE) are achieved in the off-line mode. In order to perform a high throughput analysis, efforts have been engaged in developing a faster sample purification process. Among different strategies, the introduction of special extraction sorbents, such as the restricted access media (RAM) and large particle supports (LPS), allowing the direct and repetitive injection of complex biological matrices, represents a very attractive approach. Integrated in a liquid chromatography (LC) system, these extraction supports lead to the automation, simplification and speeding up of the sample preparation process. In this paper, RAM and LPS are reviewed and particular attention is given to commercially available supports. Applications of these extraction supports, are presented in single column and column-switching configurations, for the direct analysis of compounds in various biological fluids.

  10. NICKEL – ENVIRONMENTAL ALLERGEN

    Directory of Open Access Journals (Sweden)

    Henryka Langauer-Lewowicka

    2010-06-01

    Full Text Available Nickel (Ni is ubiquitus in our biosphere because of its emission from natural and anthropogenic sources. Its toxic and carcinogenic properties are well recognised only in workers exposed to high Ni concentrations. Nickel allergy is the most common form of cutaneus hypersensitivity in general population and also in occupationally exposed groups. As sensitizing agent Ni has a high prevalence of allergic contact dermatitis. The most important known risk factor associated with nickel allergy is ear piercing and use of other jewelry in females. In general population 17 % adults and 8 % children have Ni allergy symptoms. Permanently growing Ni allergy is regarded as serious risk for public health.

  11. Pulse plating of nickel deposits

    Energy Technology Data Exchange (ETDEWEB)

    Stimetz, C.J.; Stevenson, M.F.

    1980-02-01

    Pulse plated and conventional nickel deposits have been compared for differences in morphology, mechanical properties, and microstructure. The deposits were obtained from nickel sulfamate, nickel chloride, and Watts nickel plating solutions. No significant differences were found in the direct and pulse current deposits from the sulfamate and chloride solutions; however, significant differences in microstructure, yield strength, and microhardness were observed in deposits from the Watts nickel solution.

  12. Selective Preparation of trans-Carveol over Ceria Supported Mesoporous Materials MCM-41 and SBA-15

    Directory of Open Access Journals (Sweden)

    Nariman F. Salakhutdinov

    2013-05-01

    Full Text Available Ce-modified mesoporous silica materials MCM-41 and SBA-15, namely 32 wt % Ce–Si–MCM-41, 16 wt % Ce–H–MCM-41 and 20 wt % Ce–Si–SBA-15, were prepared, characterized and studied in the selective preparation of trans-carveol by α-pinene oxide isomerization. The characterizations of these catalysts were performed using scanning electron microscopy, X-ray photoelectron spectroscopy, nitrogen adsorption and FTIR pyridine adsorption. Selective preparation of trans-carveol was carried out in the liquid phase in a batch reactor. The activity and the selectivity of catalyst were observed to be influenced by their acidity, basicity and morphology of the mesoporous materials. The formation of trans-carveol is moreover strongly influenced by the basicity of the used solvent and in order to achieve high yields of this desired alcohol it is necessary to use polar basic solvent.

  13. Functionalized SBA-15 supported nickel (II)–oxime–imine catalysts for liquid phase oxidation of olefins under solvent-free conditions

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Luna [Department of Chemistry, Jadavpur University, Kolkata 700 032 (India); Banerjee, Biplab [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Bhaumik, Asim, E-mail: msab@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Ali, Mahammad, E-mail: m_ali2062@yahoo.com [Department of Chemistry, Jadavpur University, Kolkata 700 032 (India)

    2016-05-15

    A new oxime–imine functionalized highly ordered mesoporous SBA-15 (SBA-15-NH{sub 2}-DAMO) has been synthesized via post-synthesis functionalization of SBA-15 with 3-aminopropyl-triethoxysilane followed by the Schiff base condensation with diacetylmonooxime, which was further reacted with Ni(ClO{sub 4}){sub 2} to yield the functionalized nickel catalyst SBA-15-NH{sub 2}-DAMO-Ni. All the synthesized materials were thoroughly characterized using different characterization techniques. It was found that SBA-15-NH{sub 2}-DAMO-Ni catalyzes the one-pot oxidation of olefins like styrene, cyclohexene, cyclooctene, 1-hexene and 1-octene to the corresponding benzaldehyde, cyclohexene-1-ol and cyclooctene-oxide, respectively under solvent-free conditions by using tert-butylhydroperoxide as oxidant. - Graphical abstract: A new well characterized oxime–imine functionalized highly ordered mesoporous SBA-15-NH{sub 2}-DAMO-Ni complex catalyzes the one-pot oxidation of olefins under solvent free mild conditions.

  14. Carbon nanofibers (CNFs) supported cobalt- nickel sulfide (CoNi2S4) nanoparticles hybrid anode for high performance lithium ion capacitor.

    Science.gov (United States)

    Jagadale, Ajay; Zhou, Xuan; Blaisdell, Douglas; Yang, Sen

    2018-01-25

    Lithium ion capacitors possess an ability to bridge the gap between lithium ion battery and supercapacitor. The main concern of fabricating lithium ion capacitors is poor rate capability and cyclic stability of the anode material which uses sluggish faradaic reactions to store an electric charge. Herein, we have fabricated high performance hybrid anode material based on carbon nanofibers (CNFs) and cobalt-nickel sulfide (CoNi 2 S 4 ) nanoparticles via simple electrospinning and electrodeposition methods. Porous and high conducting CNF@CoNi 2 S 4 electrode acts as an expressway network for electronic and ionic diffusion during charging-discharging processes. The effect of anode to cathode mass ratio on the performance has been studied by fabricating lithium ion capacitors with different mass ratios. The surface controlled contribution of CNF@CoNi 2 S 4 electrode was 73% which demonstrates its excellent rate capability. Lithium ion capacitor fabricated with CNF@CoNi 2 S 4 to AC mass ratio of 1:2.6 showed excellent energy density of 85.4 Wh kg -1 with the power density of 150 W kg -1 . Also, even at the high power density of 15 kW kg -1 , the cell provided the energy density of 35 Wh kg -1 . This work offers a new strategy for designing high-performance hybrid anode with the combination of simple and cost effective approaches.

  15. Engagement in Adolescent Career Preparation: Social Support, Personality and the Development of Choice Decidedness and Congruence

    Science.gov (United States)

    Hirschi, Andreas; Niles, Spencer G.; Akos, Patrick

    2011-01-01

    This longitudinal panel study investigated predictors and outcomes of active engagement in career preparation among 349 Swiss adolescents from the beginning to the end of eighth grade. Latent variable structural equation modeling was applied. The results showed that engagement in terms of self- and environmental-exploration and active career…

  16. Weighing the Issues and Consequences of Federal Program Termination: Administration on Aging Support for Career Preparation.

    Science.gov (United States)

    Craig, Bruce M.

    1982-01-01

    Describes policy decisions that have acted upon the 1982 Fiscal Year budget and funding priorities of the Administration on Aging's Gerontology Career Preparation Program, and projects the probable consequences of the policy option now being weighed to eliminate all future funding. (University of Texas Press, Box 7819, Austin, TX 78712). (NJ)

  17. Preparation of carbon nano-riber washcoat on porous silica foam as structured catalyst support.

    NARCIS (Netherlands)

    Liu, P.; Liu, Pingle; Lefferts, Leonardus

    2006-01-01

    This paper reports how a hairy layer of carbon nano-fibers can be prepared on the macro-porous silica foam produced by the sphere templating method. Firstly, three-dimensional close-packed crystals of polystyrene spheres are assembled on porous disk substrate by vacuum filtration or evaporation. The

  18. Preparation of self-supporting mesostructured silica thin film membranes as gateable interconnects for microfluidics

    NARCIS (Netherlands)

    Garcia Juez, R.; Boffa, V.; Blank, David H.A.; ten Elshof, Johan E.

    2008-01-01

    A methodology for the preparation of self-standing 100–200 nm thick mesoporous silica membrane interconnects is reported. Interconnects may become an important component in future microfluidic device technology since it allows extension of microfluidic architectures into the third dimension. The

  19. Dissolution studies on Nickel ferrite in dilute chemical decontamination formulations

    Energy Technology Data Exchange (ETDEWEB)

    Ranganathan, S. [New Brunswick Univ., Fredericton, NB (Canada). Dept. of Chemical Engineering; Srinivasan, M.P. [Bhabha Atomic Research Centre (BARC) (India). Water and Steam Chemistry Laboratory; Raghavan, P.S. [Madras Christian College, Chennai (India); Narasimhan, S.V. [Bhabha Atomic Research Centre, Bombay (India); Gopalan, R. [Madras Christian College, Chennai (India). Department of Chemistry

    2004-09-01

    Nickel ferrite is one of the important corrosion products in the pipeline surfaces of water-cooled nuclear reactors. The dissolution of the nickel ferrite by chelating agents is very sensitive to the nature of the chelant, the nature of the reductant used in the formulation and the temperature at which the dissolution studies are performed. The dissolution is mainly controlled by the reductive dissolution of the ferrite particles, but complexing agents also play a significant role in the dissolution process. This study deals with the leaching of iron and nickel from nickel ferrite prepared by the solid-state method. The dissolution studies are performed in pyridine-2,6-dicarboxylic acid (PDCA), nitrilotriacetic acid (NTA), and ethylenediaminetetraacetic acid (EDTA) formulations containing organic reductants like ascorbic acid and low oxidation state transition metal ion reductants like Fe(II)-L (where L = PDCA, NTA, EDTA) at 85 C. The dissolution of nickel ferrite in PDCA, NTA and EDTA formulations is influenced by the presence of reductants in the formulations. The addition of Fe(II)-L in the formulation greatly enhances the dissolution of nickel ferrite. The preferential leaching of nickel over iron during the dissolution of nickel ferrite was observed in all the formulations. (orig.)

  20. Nickel-cobalt hydroxide nanosheets: Synthesis, morphology and electrochemical properties.

    Science.gov (United States)

    Schneiderová, Barbora; Demel, Jan; Zhigunov, Alexander; Bohuslav, Jan; Tarábková, Hana; Janda, Pavel; Lang, Kamil

    2017-08-01

    This paper reports the synthesis, characterization, and electrochemical performance of nickel-cobalt hydroxide nanosheets. The hydroxide nanosheets of approximately 0.7nm thickness were prepared by delamination of layered nickel-cobalt hydroxide lactate in water and formed transparent colloids that were stable for months. The nanosheets were deposited on highly oriented pyrolytic graphite by spin coating, and their electrochemical behavior was investigated by cyclic voltammetry in potassium hydroxide electrolyte. Our method of electrode preparation allows for studying the electrochemistry of nanosheets where the majority of the active centers can participate in the charge transfer reaction. The observed electrochemical response was ascribed to mutual compensation of the cobalt and nickel response via electron sharing between these metals in the hydroxide nanosheets, a process that differentiates the behavior of nickel-cobalt hydroxide nanosheets from single nickel hydroxide or cobalt hydroxide nanosheets or their physical mixture. The presence of cobalt in the nickel-cobalt hydroxide nanosheets apparently decreases the time of electrochemical activation of the nanosheet layer, which for the nickel hydroxide nanosheets alone requires more potential sweeps. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Nickel films: Nonselective and selective photochemical deposition and properties

    International Nuclear Information System (INIS)

    Smirnova, N.V.; Boitsova, T.B.; Gorbunova, V.V.; Alekseeva, L.V.; Pronin, V.P.; Kon'uhov, G.S.

    2006-01-01

    Nickel films deposited on quartz surfaces by the photochemical reduction of a chemical nickel plating solution were studied. It was found that the deposition of the films occurs after an induction period, the length of which depends on the composition of the photolyte and the light intensity. Ni particles with a mean diameter of 20-30 nm were detected initially by transmission electron microscopy. The particles then increased in size (50 nm) upon irradiation and grouped into rings consisting of 4-5 particles. Irradiation with high-intensity light produces three-dimensional films. The calculated extinction coefficient of the nickel film was found to be 4800 L mol -1 cm -1 . Electron diffraction revealed that the prepared amorphous nickel films crystallize after one day of storage. It was determined that the films exhibit catalytic activity in the process of nickel deposition from nickel plating solution. The catalytic action remains for about 5-7 min after exposure of the films to air. The processes of selective and nonselective deposition of the nickel films are discussed. The use of poly(butoxy titanium) in the process of selective photochemical deposition enables negative and positive images to be prepared on quartz surfaces

  2. Structure investigations of electrodeposited nickel

    Energy Technology Data Exchange (ETDEWEB)

    Vertes, A.; Czako-Nagy, I.; Lakatos-Varsani, M. (Eoetvoes Lorand Tudomanyegyetem, Budapest (Hungary). Dept. of Physical Chemistry); Kajcsos, Z. (Hungarian Academy of Sciences, Budapest. Central Research Inst. for Physics); Csordas, L. (Eoetvoes Lorand Tudomanyegyetem, Budapest (Hungary). Dept. of Solid State Physics); Brauer, G. (Zentralinstitut fuer Kernforschung, Rossendorf bei Dresden (German Democratic Republic)); Leidheiser, H. Jr. (Lehigh Univ., Bethlehem, PA (USA). Center for Surface and Coatings Research)

    1982-08-01

    Nickel, electrodeposited under different conditions and yielding different values of stress, was investigated by positron annihilation (lifetime and Doppler-broadening), Moessbauer effect and X-ray diffraction measurements. Two-component positron lifetime spectra were obtained. The first component is thought to result from bulk annihilation and trapping at single trapping centres (TC). Estimations of TC-concentrations are obtained by means of the trapping model. The second one possibly denotes annihilation at voids, the number of which is dependent on the stress in the deposit. Results of Doppler-broadening measurements support this interpretation. The Moessbauer results show differences in the magnetic orientation in the three samples examined.

  3. Controlled metal nitrate decomposition for the preparation of supported metal Catalysts

    NARCIS (Netherlands)

    Wolters, M.

    2010-01-01

    High surface area supported metal (oxide) catalysts are essential for the production of fuels, chemicals, pharmaceuticals and the abatement of environmental pollution. Impregnation of high surface area supports, often silica or alumina, followed by drying, calcination and reduction is one of the

  4. Preparing School Counselors to Support LGBT Youth: The Roles of Graduate Education and Professional Development

    Science.gov (United States)

    Kull, Ryan M.; Kosciw, Joseph G.; Greytak, Emily A.

    2017-01-01

    This study examined whether school counselors' LGBT-related graduate education and professional development predicted more frequent efforts to support LGBT students, and whether their LGBT-related self-efficacy mediated the relationship between their training experiences and supportive efforts. Results from ordinary least squares (OLS) regression…

  5. Systemic nickel hypersensitivity and diet: myth or reality?

    Science.gov (United States)

    Pizzutelli, S

    2011-02-01

    Nickel is a very common metal contained in many everyday objects and is the leading cause of ACD (Allergic Contact Dermatitis). Nickel is present in most of the constituents of a normal diet, but some food groups are usually considered to be richer. However, the nickel content of specific food can vary widely, depending on many factors. Thus, the daily intake of nickel is also highly variable both among different populations and in a single individual, in different seasons and even in different days. Measuring precisely the daily intake of nickel from food and drinks is extremely difficult, if not impossible. The relationship between ACD and contact with nickel is undisputed and widely confirmed in literature. The situation is different for systemic nickel allergy syndrome (SNAS). The SNAS can have cutaneous signs and symptoms (Systemic Contact Dermatitis or SCD) or extracutaneous signs and symptoms (gastrointestinal, respiratory, neurological, etc.).The occurrence of SCD as a systemic reaction to the nickel normally assumed in the daily diet is very controversial. A rigorous demonstration of the relationship between SCD and nickel is extremely difficult. In particular, further and larger studies are needed to assess the reality and the prevalence of nickel urticaria. With respect to nickel-related gastrointestinal symptoms, as well as chronic fatigue syndrome, fibromyalgia, headache, recurring cold sores and recurrent infections in general, the data available in literature are not conclusive and the studies lack the support of clear, first-hand evidence. With respect to respiratory disorders, the role of food nickel and the effectiveness of a dietary treatment have been assumed but not proven. In fact, the usefullness of a therapeutic low-nickel diet is controversial: rare, if not exceptional, and limited to very sporadic cases of SCD. Additionally, the quantitative and qualitative composition of a low-nickel diet presents few certainties and many uncertainties

  6. Synthesis and Characterization of Nickel Phosphate Nanoparticles and VSB-5 with Quaternary Ammonium Base

    Directory of Open Access Journals (Sweden)

    Abdolraouf Samadi–Maybodi

    2011-01-01

    Full Text Available Nickel phosphate VSB-5 (Versailles Santa Barbara-5 was synthesized with microwave for 1 h and followed by conventional oven for 2 days in the presence of (2-hydroxyethyl trimethylammonium hydroxide as template. By addition of ethylene glycol, nickel phosphate nanoparticle was prepared with average size of 55 nm. Also, nickel phosphate nanoparticles was synthesized by microwave assisted hydrothermal using tetrapropylammonium hydroxide as template. The spherical nickel phosphate crystals with average diameter of 80 nm were successfully synthesized in the presence of tetrapropylammonium hydroxide. Furthermore, spherical nanosized crystals were prepared with polyethylene glycol: water volume ratio of 1:1 using (2-hydroxyethyl trimethylammonium hydroxide as template.

  7. New methodology of preparation support for solid oxide fuel cells using different pore forming agent

    Energy Technology Data Exchange (ETDEWEB)

    Fiuza, Raigenis da P.; Guedes, Bruna C.F.; Silva, Marcos A. da; Carvalho, Luiz F.V. de; Boaventura, Jaime S. [Universidade Federal da Bahia (IQ/UFBA), Salvador, BA (Brazil). Inst. de Quimica; Pontes, Luiz A.M. [Universidade Federal da Bahia (EP/UFBA), Salvador, BA (Brazil). Escola Politecnica. Programa de Pos-Graduacao em Engenharia Quimica

    2008-07-01

    The development of environment-friendly energy sources has been of the most important scientific and technological area. Solid oxide fuel cells (SOFC) are very promising alternative for their ability to handle renewable fuels with low emissions and high efficiency. However, this device requires massive improvement before commercial application. This work studies the pore formation in the cell anode and cathode with NaHCO{sub 3} or citric acid, comparing to graphite. The three agents make pore with similar features, but the use of NaHCO{sub 3} and citric acid considerably improves the adhesion of the electrode-electrolyte interface, critical characteristic for good cell efficiency. The prepared anode-electrolyte-cathode structure was studied by SEM technique. The SOFC prepared using citric acid was tested with gaseous ethanol, natural gas and hydrogen. For all these three fuels the SOFC shows virtually no overpotential, indicating the good ionic conductance of the electrodes-electrolyte interface.. (author)

  8. Catalyst component interactions in nickel/alumina catalyst

    OpenAIRE

    Kiš Erne E.; Lazić Matilda M.; Bošković Goran C.

    2007-01-01

    The influence of nickel loading (5; 10; 20 wt% Ni), temperature of heat treatment (400; 700; 1100°C) and way of catalyst preparation on the catalyst component interactions (CCI) in the impregnated, mechanical powder mixed and co-precipitated catalyst was investigated. For sample characterization, low temperature nitrogen adsorption (LTNA) and X-ray diffraction (XRD) were applied. Significant differences were revealed, concerning CCI in dependence of nickel loading, temperature of heat treatme...

  9. Preparation and heat treatment characterization of alumina-based ceramic catalyst supports

    International Nuclear Information System (INIS)

    Che Seman Mahmood; Sarimah Mahat; Che Nor Aiza Jaafar

    2000-01-01

    Physical and chemical properties of support materials are as equally important as the precursor metals to the overall performance and function of the heterogeneous catalyst system. Studies on support properties could lead to development of procedure for production of catalyst designed for a desired functionality. This paper reports on the studies of changes of physical properties of alumina and mullite, that have been synthesized for catalyst support, after undergoing heat treatment. The crystallization has been studied by XRD technique, and the phase transformation was monitored by TGA and DTA methods. The surface area changes were followed by BET nitrogen adsorption method

  10. Soil, nickel and low nickel food

    Science.gov (United States)

    Chami, Ziad Al; Cavoski, Ivana; Mondelli, Donato; Mimiola, Giancarlo; Miano, Teodoro

    2013-04-01

    Nickel is an ubiquitous trace element and occurs in soil, water, air and in the biosphere. Ni is an essential element for several plants, microorganisms and vertebrates. Human requirement for Ni has not been conclusively demonstrated. Nickel is normally present in human tissues at low concentration and, under conditions of high exposure, these levels may increase significantly. Food is the major source of Ni exposure. Nickel is present in many food products, especially vegetables. The amount of Ni present in vegetables is increasing because of environmental contamination and cultural practices. It has been demonstrated that the consumption of a Ni-rich diet can cause an increase of immunological disorders including Systemic Ni Allergy Syndrome (SNAS). The SNAS patients are currently treated with a diet that is closely Ni-free. Therefore, there is a need to produce certified and guaranteed vegetables with a low Ni concentration in the market. The proposed research aims to develop new methods for vegetable production and innovative cultural practices through a suitable choice of agricultural soil, cultivar, amendments and fertilizers as well as good agricultural practices in order to reduce Ni plant uptake and its translocation to the edible plant parts and therefore to produce Ni-free food products for SNAS patients.

  11. X-ray diffraction and Moessbauer studies on superparamagnetic nickel ferrite (NiFe{sub 2}O{sub 4}) obtained by the proteic sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, N.A.S. [Departamento de Engenharia Metalúrgica e de Materiais, Centro de Tecnologia, Campus do Pici, Universidade Federal do Ceará – UFC, 60455-760 Fortaleza, CE (Brazil); Utuni, V.H.S.; Silva, Y.C. [Departamento de Física, Universidade Federal do Ceará – UFC, Campus do Pici, 60440-970 Fortaleza, CE (Brazil); Kiyohara, P.K. [Instituto de Física, Universidade de São Paulo – USP, 05315-970 São Paulo, SP (Brazil); Vasconcelos, I.F. [Departamento de Engenharia Metalúrgica e de Materiais, Centro de Tecnologia, Campus do Pici, Universidade Federal do Ceará – UFC, 60455-760 Fortaleza, CE (Brazil); Miranda, M.A.R., E-mail: marcus.a.r.miranda@gmail.com [Departamento de Física, Universidade Federal do Ceará – UFC, Campus do Pici, 60440-970 Fortaleza, CE (Brazil); Sasaki, J.M. [Departamento de Física, Universidade Federal do Ceará – UFC, Campus do Pici, 60440-970 Fortaleza, CE (Brazil)

    2015-08-01

    Nickel ferrite (NiFe{sub 2}O{sub 4}) nanoparticles were synthesized by the proteic sol–gel method at synthesis temperature of 250 °C, 300 °C and 400 °C, with the objective of obtaining superparamagnetic nanoparticles. Thermogravimetric analysis (TGA) and temperature-programed oxidation (TPO) presented peaks around 290 °C indicating that nickel ferrite was forming at this temperature. X-ray powder diffraction (XRPD) confirmed that the polycrystalline sample was single phased NiFe{sub 2}O{sub 4} with space group Fd3m. Scherrer equation applied to the diffraction patterns and transmission electron microscopy (TEM) images showed that the size of the nanoparticles ranged from 9 nm to 13 nm. TEM images also revealed that the nanoparticles were agglomerated, which was supported by the low values of surface area provided by the Brunauer-Emmet-Teller (BET) method. Moessbauer spectroscopy presented spectra composed of a superposition of three components: a sextet, a doublet and a broad singlet pattern. The sample synthetized at 300 °C had the most pronounced doublet pattern characteristic of superparamagnetic nanoparticles. In conclusion, this method was partially successful in obtaining superparamagnetic nickel ferrite nanoparticles, in which the synthetized samples were a mixture of nanoparticles with blocking temperature above and below room temperature. Magnetization curves revealed a small hysteresis, supporting the Moessbauer results. The sample with the higher concentration of superparamagnetic nanoparticles being the one synthetized at 300 °C. - Highlights: • Superparamagnetic nickel ferrite nanoparticles were grown by the proteic sol–gel method. • The proteic sol–gel method provided superparamagnetic nickel ferrite nanoparticles with sizes in the range of 9–13 nm. • Nickel ferrite nanoparticles were prepared at temperatures as low as 250 °C. • The nickel ferrite nanoparticles were studied by x-ray diffraction and Moessbauer.

  12. A versatile sonication-assisted deposition-reduction method for preparing supported metal catalysts for catalytic applications.

    Science.gov (United States)

    Padilla, Romen Herrera; Priecel, Peter; Lin, Ming; Lopez-Sanchez, Jose Antonio; Zhong, Ziyi

    2017-03-01

    This work aims to develop a rapid and efficient strategy for preparing supported metal catalysts for catalytic applications. The sonication-assisted reduction-precipitation method was employed to prepare the heterogeneous mono- and bi-metallic catalysts for photocatalytic degradation of methyl orange (MO) and preferential oxidation (PROX) of CO in H 2 -rich gas. In general, there are three advantages for the sonication-assisted method as compared with the conventional methods, including high dispersion of metal nanoparticles on the catalyst support, the much higher deposition efficiency (DE) than those of the deposition-precipitation (DP) and co-precipitation (CP) methods, and the very fast preparation, which only lasts 10-20s for the deposition. In the AuPd/TiO 2 catalysts series, the AuPd(3:1)/TiO 2 catalyst is the most active for MO photocatalytic degradation; while for PROX reaction, Ru/TiO 2 , Au-Cu/SBA-15 and Pt/γ-Al 2 O 3 catalysts are very active, and the last one showed high stability in the lifetime test. The structural characterization revealed that in the AuPd(3:1)/TiO 2 catalyst, Au-Pd alloy particles were formed and a high percentage of Au atoms was located at the surface. Therefore, this sonication-assisted method is efficient and rapid in the preparation of supported metal catalysts with obvious structural characteristics for various catalytic applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Production method of nickel electrode

    Science.gov (United States)

    Ikeda, H.; Ohira, T.

    1982-01-01

    A nickel electrode having improved charging efficiency, an increased coefficient of discharging utilization, and large capacity is disclosed. Nickel hydroxide or nickel oxide is retained in a porous nickel substrate which is immersed in an aqueous solution of cobalt acetate with a pH 4.0 to 6.8. The electrode thus obtained is then immersed in an alkaline solution or heated to change cobalt acetate into cobalt hydroxide or cobalt oxide whereby the surface of nickel active material is covered with cobalt crystals and alloying of cobalt and nickel is promoted at the same time.

  14. Preparing the 1993--94 Safeguards Implementation Support Programme for IAEA

    International Nuclear Information System (INIS)

    Green, L.

    1993-01-01

    The 1993-94 Safeguards Implementation Support (IS) Program describes the Department of Safeguards' program of implementation support for the coming two years. The main body of the document describes the IS program for IAEA. A detailed description of the individual IS needs for 1993-1994 is contained in an annex that specifies the nee, assigns priorities and lists tasks and activities underway to address the need. Other annexes address policy and procedures for program planning and management, current Member State Support Programs (MSSP) tasks, and identification of MSSP resources required for implementation of developed technologies that could be provided. The primary responsibility for supporting the implementation of safeguards technology is with the support divisions of the Department of Safeguards. However, in this time of limited resources it is essential that, where possible, the Department receives assistance from MSSPs that have the needed resources. This document should serve as a guide for IAEA, in planning implementation support activities and for identifying tasks for MSSPs wishing to provide assistance

  15. Methane dry reforming over Ni catalysts supported on Ce–Zr oxides prepared by a route involving supercritical fluids

    Directory of Open Access Journals (Sweden)

    Smirnova Marina Yu.

    2017-12-01

    Full Text Available Ce0.5Zr0.5O2 mixed oxides were prepared in a flow reactor in supercritical isopropanol with acetylacetone as a complexing agent. Variation of the nature of the Zr salt and the temperature of synthesis affected the phase composition, morphology and specific surface area of oxides. X-ray diffraction and Raman spectroscopy studies revealed formation of metastable t” and t’ phases. Oxides are comprised of agglomerates with sizes depending on the synthesis parameters. Loading NiO decreases the specific surface area without affecting X-ray particle sizes of supports. Such sintering was the most pronounced for a support with the highest specific surface area, which resulted in the lowest surface content of Ni as estimated by X-ray photoelectron spectroscopy and in the formation of flattened NiO particles partially embedded into the support. The catalytic activity and stability of these samples in the dry reforming of methane were determined by the surface concentration of Ni and the morphology of its particle controlled by the metal-support interaction, which also depends on the type of catalyst pretreatment. Samples based on ceria-zirconia oxides prepared under these conditions provide a higher specific catalytic activity as compared with the traditional Pechini route, which makes them promising for the practical application.

  16. Method of preparing Ru-immobilized polymer-supported catalyst for hydrogen generation from NaBH{sub 4} solution

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ching-Wen; Chen, Chuh-Yung; Huang, Yao-Hui [Department of Chemical Engineering, National Cheng Kung University, No.1, University Road, Tainan City 70101 (China)

    2009-03-15

    A method of preparing a polymer-supported catalyst for hydrogen generation is introduced in this article. This polymer-supported catalyst is the structure of ruthenium (Ru) nanoparticle immobilized on a monodisperse polystyrene (PSt) microsphere. The diameter of the Ru nanoparticle is around 16 nm, and the diameter of the PSt microsphere is 2.65 um. This preparation method is accomplished by two unique techniques: one is sodium lauryl sulfate/sodium formaldehyde sulfoxylate (SLS/SFS) interface-initiated system, the other is 2-methacrylic acid 3-(bis-carboxymethylamino)-2-hydroxy-propyl ester (GMA-IDA) chelating monomer. By taking advantage of these two techniques, Ru{sup 3+} ion will be chelated and then reduced to Ru{sup (0)} nanoparticle over PSt surface predominantly. The hydrolysis of alkaline sodium borohydride (NaBH{sub 4}) solution catalyzed by this Ru-immobilized polymer-supported catalyst is also examined in this article. It reveals that the hydrogen generation rate is 215.9 ml/min g-cat. in a diluted solution containing 1 wt.% NaBH{sub 4} and 1 wt.% NaOH, and this Ru-immobilized polymer-supported catalyst could be recycled during the reaction. (author)

  17. Data in support of preparation and functionalization of a clickable polycarbonate monolith

    Directory of Open Access Journals (Sweden)

    Yuanrong Xin

    2016-06-01

    Full Text Available This data article provides supplementary figures to the research article entitled, “Phase separation approach to a reactive polycarbonate monolith for “click” modifications” (Xin et al., Polymer, 2015, doi:10.1016/j.polymer.2015.04.008. Here, the nitrogen adsorption/desorption isotherms of the prepared porous polycarbonate monolith are shown to classify its inner structure and calculate the specific surface area. The monoliths were modified by using the thiol-ene click chemistry and the olefin metathesis, which was examined by contact angle measurements, FT-IR, solid state 13C NMR spectroscopy as well as thermogravimetric analysis.

  18. Preparation of titanium dioxide photocatalyst loaded onto activated carbon support using chemical vapor deposition: A review paper

    International Nuclear Information System (INIS)

    Li Puma, Gianluca; Bono, Awang; Krishnaiah, Duduku; Collin, Joseph G.

    2008-01-01

    Various methods to prepare and characterize TiO 2 photocatalyst loaded onto activated carbon (AC) support have been developed over the last decade. This photocatalyst has been used in a variety of investigations, i.e. from water decontamination to direct pollutant degradation in aqueous and gas phase systems using UV irradiation and lately with the assistance of ultrasonic sound waves. Chemical vapor deposition (CVD) method is one of the most promising and well-researched methods for deposition of catalysts onto supports. Given its advantage, from an engineering and fundamental aspect, CVD method also has commercial applications. A detailed search of published reports of these investigations was carried out and analyzed in this paper with focus on CVD techniques, activated carbon support and sonication

  19. The use of earth observation and decision support systems for the restoration of open-cast nickel mines in Evia, central Greece

    NARCIS (Netherlands)

    Ganas, A.; Aerts, J.C.J.H.; Astaras, T.; de Vente, J.; Frogoudakis, E.; Labrinos, N.

    2004-01-01

    We have developed a decision support system (DSS) for open mining areas which reflects and simulates the major decision steps of a mining expert (engineer, manager) during the formulation of a restoration plan. The software supports the mining expert to structure the various restoration alternatives

  20. AFM characterization of solid-supported lipid multilayers prepared by spin-coating.

    Science.gov (United States)

    Pompeo, G; Girasole, M; Cricenti, A; Cattaruzza, F; Flamini, A; Prosperi, T; Generosi, J; Castellano, A Congiu

    2005-06-15

    Lipids are the principal components of biologically relevant structures as cellular membranes. They have been the subject of many studies due to their biological relevance and their potential applications. Different techniques, such as Langmuir-Blodgett and vesicle-fusion deposition, are available to deposit ordered lipid films on etched surfaces. Recently, a new technique of lipid film deposition has been proposed in which stacks of a small and well-controlled number of bilayers are prepared on a suitable substrate using a spin-coater. We studied the morphological properties of multi-layers made of cationic and neutral lipids (DOTAP and DOPC) and mixtures of them using dynamic mode atomic force microscopy (AFM). After adapting and optimizing, the spin-coating technique to deposit lipids on a chemically etched Silicon (1,0,0) substrate, a morphological nanometer-scale characterization of the aforementioned samples has been provided. The AFM study showed that an initial layer of ordered vesicles is formed and, afterward, depending on details of the spin-coating preparation protocol and to the dimension of the silicon substrate, vesicle fusion and structural rearrangements of the lipid layers may occur. The present data disclose the possibility to control the lipid's structures by acting on spin-coating parameters with promising perspectives for novel applications of lipid films.

  1. Preparation and Characterization of Uranium Oxides in Support of the K Basin Sludge Treatment Project

    International Nuclear Information System (INIS)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2008-01-01

    Uraninite (UO2) and metaschoepite (UO3-2H2O) are the uranium phases most frequently observed in K Basin sludge. Uraninite arises from the oxidation of uranium metal by anoxic water and metaschoepite arises from oxidation of uraninite by atmospheric or radiolytic oxygen. Studies of the oxidation of uraninite by oxygen to form metaschoepite were performed at 21 C and 50 C. A uranium oxide oxidation state characterization method based on spectrophotometry of the solution formed by dissolving aqueous slurries in phosphoric acid was developed to follow the extent of reaction. This method may be applied to determine uranium oxide oxidation state distribution in K Basin sludge. The uraninite produced by anoxic corrosion of uranium metal has exceedingly fine particle size (6 nm diameter), forms agglomerates, and has the formula UO2.004 ± 0.007; i.e., is practically stoichiometric UO2. The metaschoepite particles are flatter and wider when prepared at 21 C than the particles prepared at 50 C. These particles are much smaller than the metaschoepite observed in prolonged exposure of actual K Basin sludge to warm moist oxidizing conditions. The uraninite produced by anoxic uranium metal corrosion and the metaschoepite produced by reaction of uraninite aqueous slurries with oxygen may be used in engineering and process development testing. A rapid alternative method to determine uranium metal concentrations in sludge also was identified.

  2. Mechanochemical synthesis of stoichiometric nickel and nickel-zinc ferrite powders with Nicolson-Ross analysis of absorption coefficients

    Directory of Open Access Journals (Sweden)

    Jovalekić Čedomir

    2012-01-01

    Full Text Available The interest in finding new methods for preparation of nickel ferrite (NiFe2O4 and nickel-zinc ferrite (NixZn1-xFe2O4 powders has recently increased, due to the fact that physical and chemical properties of these soft magnetic materials depend strongly on the preparation conditions. In this paper, powder samples of ferrites were obtained by: 1 classic sintering procedure (NixZn1-xFe2O4, x = 0.9 and 2 planetary mill synthesis (both NiFe2O4 and NixZn1-xFe2O4. Mechanochemical reaction leading to the formation of NixZn1-xFe2O4 (x = 1 and 0.9 spinel phase was monitored by SEM, TEM, and XRD. Values of the real and imaginary parts of permittivity and permeability were measured for the obtained nickel and nickel-zinc ferrite samples in the 7-12 GHz frequency range. Based on the obtained results, the EMR absorption coefficients were calculated for all three sample types. It has been concluded that the method of preparation and the final particle size influence the EMR absorption coefficient of nickel and nickel-zinc ferrites.

  3. Preparation, characterization, and activity of α-Ti(HPO4)2 supported metallocene catalysts

    Science.gov (United States)

    Shi, Yasai; Yuan, Yuan; Xu, Qinghong; Yi, Jianjun

    2016-10-01

    A series of heterogeneous catalysts by loading metallocenes on surface of α-Ti(HPO4)2, a kind of solid acid, has been synthesized. Polymerization of alkenes, including ethylene and propylene, based on participation of the heterogeneous catalysts were studied and the results were compared to metallocenes supported on silica gel, α-Zr(HPO4)2 and clay. Higher catalytic activity, larger polymer molecular weight and narrow distribution of polymer molecular weight were obtained. Acidic strength of the support and its influence to metallocenes were studied to discover intrinsic factors in the polymerizations.

  4. Fracture of rotary nickel titanium instruments

    Directory of Open Access Journals (Sweden)

    Rajendra Kumar Tewari

    2017-01-01

    Full Text Available With the advent of rotary nickel titanium (NiTi instruments, preparation of curved canals have become easy but chances of instrument separation have increased. Such an instrument separation can cause procedural problems in rendering endodontic therapy. There are various factors that cause separation of rotary NiTi instruments. These factors, various failure mechanisms and impact on the prognosis of instrument separation have to be well understood by the clinician.

  5. Pt nanoparticles supported over Ce-Ti-O: the solvothermal and photochemical approaches for the preparation of catalytic materials

    International Nuclear Information System (INIS)

    Silva, Adrian M. T.; Machado, Bruno F.; Gomes, Helder T.; Figueiredo, Jose L.; Drazic, Goran; Faria, Joaquim L.

    2010-01-01

    Ce-Ti-O supports with different Ce/Ti molar ratios were synthesized by the solvothermal method using hexadecyltrimethylammonium bromide. Pt nanoparticles were then supported by photochemical deposition. The shape, size, and structure of these materials were analyzed by high-resolution transmission electron microscopy. The single CeO 2 support was also prepared, consisting of agglomerated cubic particles ranging from ∼3 to 8 nm. When titania was combined with ceria, a nanostructured architecture was produced, evidencing the strong influence of Ti in the support structure. Photodeposition of Pt nanoparticles is more efficient on Ce-Ti-O supports than in pristine CeO 2 . Crystalline Pt nanoparticles (mainly of ∼2 to 4 nm) were detected. The catalytic properties of the materials were tested in the selective hydrogenation of cinnamaldehyde to cinnamyl alcohol. It was observed that Pt supported on Ce-Ti-O is more active and selective than Pt on CeO 2 or TiO 2 separately. The catalyst with 40 mol% Ce leads to total conversion of cinnamaldehyde in a few minutes; however, higher selectivity toward the desired product (cinnamyl alcohol) was obtained with higher amounts of Ce (50 mol%).

  6. Preparation of Silver and Silver-backing self-supported thin targets by high vacuum evaporation

    OpenAIRE

    Cabanelas, P.; Galaviz, D.; Henriques, A.; Sánchez-Benítez, A.; Teubig, P.; Velho, P.

    2016-01-01

    We have produced in the Nuclear Physics Center in Lisbon thin film self-supported targets of Ag, LiF/Ag and CaF$_2$/Ag by a high vacuum resistance evaporation method. The production setup, materials, methods, characterization and results are described.

  7. Combined silica sources to prepare preferentially oriented silicalite-1 layers on various supports

    Czech Academy of Sciences Publication Activity Database

    Hrabánek, Pavel; Zikánová, Arlette; Drahokoupil, Jan; Prokopová, Olga; Brabec, Libor; Jirka, Ivan; Matějková, Martina; Fíla, V.; de la Iglesia, O.; Kočiřík, Milan

    2013-01-01

    Roč. 174, July 2013 (2013), s. 154-162 ISSN 1387-1811 R&D Projects: GA ČR(CZ) GAP204/11/1206 Institutional support: RVO:61388955 ; RVO:68378271 Keywords : zeolite * synthesis * orientation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.209, year: 2013

  8. Preparation of MgO Catalytic Support in Shaped Mesoporous High Surface Area Form

    Czech Academy of Sciences Publication Activity Database

    Gulková, Daniela; Šolcová, Olga; Zdražil, Miroslav

    2004-01-01

    Roč. 76, 1-3 (2004), s. 137-149 ISSN 1387-1811 R&D Projects: GA AV ČR IAA4072306 Institutional research plan: CEZ:AV0Z4072921 Keywords : MgO support * sigh Surface area * texture Subject RIV: CC - Organic Chemistry Impact factor: 2.093, year: 2004

  9. Allergy risks with laptop computers - nickel and cobalt release.

    Science.gov (United States)

    Midander, Klara; Hurtig, Anna; Borg Tornberg, Anette; Julander, Anneli

    2016-06-01

    Laptop computers may release nickel and cobalt when they come into contact with skin. Few computer brands have been studied. To evaluate nickel and cobalt release from laptop computers belonging to several brands by using spot tests, and to quantify the release from one new computer by using artificial sweat solution. Nickel and cobalt spot tests were used on the lid and wrist supports of 31 laptop computers representing five brands. The same surfaces were tested on all computers. In addition, one new computer was bought and dismantled for release tests in artificial sweat according to the standard method described in EN1811. Thirty-nine per cent of the laptop computers were nickel spot test-positive, and 6% were positive for cobalt. The nickel on the surface could be worn off by consecutive spot testing of the same surface. The release test in artificial sweat of one computer showed that nickel and cobalt were released, although in low concentrations. As they constitute a potential source of skin exposure to metals, laptop computers should qualify as objects to be included within the restriction of nickel in REACH, following the definition of 'prolonged skin contact'. Skin contact resulting from laptop use may contribute to an accumulated skin dose of nickel that can be problematic for sensitized individuals. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Preparation and application of zirconium sulfate supported on SAPO-34 molecular sieve as solid acid catalyst for esterification

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Dongyan, E-mail: xdy0156@sina.com; Ma, Hong; Cheng, Fei

    2014-05-01

    Graphical abstract: - Highlights: • SAPO-34 supported zirconium sulfate solid acid catalyst was prepared. • Esterification of acetic acid with ethanol can be catalyzed by ZS/SAPO-34. • The hydration of ZS is vital to the acidic property and catalytic performance. • The ZS/SAPO-34 catalyst treated at 200 °C shows good reusability. - Abstract: Zirconium sulfate (ZS) was supported on SAPO-34 molecular sieve by using an incipient wetness impregnation method with zirconium sulfate as the precursor. The as-prepared catalysts were used as solid acid catalyst for esterification reaction of acetic acid with ethanol. The influence of calcination temperature on the acidic property, catalytic activity, and reusability of ZS/SAPO-34 catalysts were mainly investigated. FT-IR, SEM, EDS and TG analysis have been carried out to demonstrate the characteristics of ZS/SAPO-34 catalysts. It was found that the 30 wt%ZS/SAPO-34 catalysts display the property of superacid irrespective of calcination temperature. The ZS/SAPO-34 catalyst treated at 200 °C can enhance the interaction between the supported ZS and SAPO-34 and keep the catalyst remaining substantially active after several reaction cycles. However, further increasing calcination temperature will cause the transfer of ZS from hydrate to anhydrous phase, and thus the decrease of activity.

  11. Preparation of Zeolitic Imidazolate Framework-8 (ZIF-8) Membrane on Porous Polymeric Support via Contra-Diffusion Method

    KAUST Repository

    Tan, Xiaoyu

    2016-05-18

    In the last decade, many attempts were made to put metal organic frameworks (MOFs) in industrial applications, but most of these efforts weren’t successfully. As one of the few MOFs produced on industrial scale, ZIF-8 has interesting pore size, huge internal surface area and great thermal and chemical stability. Therefore, ZIF-8 might become the first MOF, which will be applied in industrial separation processes. In this thesis, a synthesis study is presented, which leads to a cheap and convenient way to
fabricate defect-free and thin ZIF-8 membranes on porous polymeric supports showing high selectivity and high gas permeance. The ZIF-8 layers were produced via a contra-diffusion method. Several polymeric membranes were employed as support in this study, such as PAN, PEI, PSU, PA and PTSC. We studied the influence of the polymeric support properties for the ZIF-8 membrane preparation and optimized the ZIF-8 preparation conditions. The ZIF-8 membranes were characterized via scanning electron microscopy (SEM) and X-ray diffraction (XRD). For gas permeation test, we chose a Wicke-Kallenbach apparatus to measure membrane’s gas permeance and selectivity. One of the best ZIF-8 membranes exhibited a hydrogen permeance of 3.45 × 10-8 mol m-2 s-1 Pa-1 and
an ideal selectivity of hydrogen over propane of about 500.

  12. The Impact of Ce-Zr Addition on Nickel Dispersion and Catalytic Behavior for CO2 Methanation of Ni/AC Catalyst at Low Temperature

    Directory of Open Access Journals (Sweden)

    Minh Cam Le

    2017-01-01

    Full Text Available The CO2 methanation was studied over 7 wt.% nickel supported on Ce0.2Zr0.8O2/AC to evaluate the correlation of the structural properties with catalytic performance. The catalysts were investigated in more detail by means of X-ray diffraction (XRD, transmission electron microscopy (TEM, and scanning electron microscopy (SEM. A sample of 7 wt.% nickel loading supported on activated carbon (AC was also prepared for comparison. The results demonstrated that the ceria-zirconia solid solution phase could disperse and stabilize the nickel species more effectively and resulted in stronger interaction with nickel than the parent activated carbon phase. Therefore, 7% Ni/Ce0.2Zr0.8O2/AC catalyst exhibited higher activity for CO2 reduction than 7% Ni//AC. It can attain 85% CO2 conversion at 350°C and have a CH4 selectivity of 100% at a pressure as low as 1 atm. The high activity of prepared catalysts is attributed to the good interaction between Ni and Ce0.2Zr0.8O2 and the high CO2 adsorption capacity of the activated carbon as well.

  13. Influence of preparation method on supported Cu-Ni alloys and their catalytic properties in high pressure CO hydrogenation

    DEFF Research Database (Denmark)

    Wu, Qiongxiao; Eriksen, Winnie L.; Duchstein, Linus Daniel Leonhard

    2014-01-01

    (50 bar CO and 50 bar H2). These alloy catalysts are highly selective (more than 99 mol%) and active for methanol synthesis; however, loss of Ni caused by nickel carbonyl formation is found to be a serious issue. The Ni carbonyl formation should be considered, if Ni-containing catalysts (even...

  14. Supported Pd-Au Membrane Reactor for Hydrogen Production: Membrane Preparation, Characterization and Testing.

    Science.gov (United States)

    Iulianelli, Adolfo; Alavi, Marjan; Bagnato, Giuseppe; Liguori, Simona; Wilcox, Jennifer; Rahimpour, Mohammad Reza; Eslamlouyan, Reza; Anzelmo, Bryce; Basile, Angelo

    2016-05-09

    A supported Pd-Au (Au 7wt%) membrane was produced by electroless plating deposition. Permeation tests were performed with pure gas (H₂, H₂, N₂, CO₂, CH₄) for long time operation. After around 400 h under testing, the composite Pd-Au membrane achieved steady state condition, with an H₂/N₂ ideal selectivity of around 500 at 420 °C and 50 kPa as transmembrane pressure, remaining stable up to 1100 h under operation. Afterwards, the membrane was allocated in a membrane reactor module for methane steam reforming reaction tests. As a preliminary application, at 420 °C, 300 kPa of reaction pressure, space velocity of 4100 h(-1), 40% methane conversion and 35% hydrogen recovery were reached using a commercial Ni/Al₂O₃ catalyst. Unfortunately, a severe coke deposition affected irreversibly the composite membrane, determining the loss of the hydrogen permeation characteristics of the supported Pd-Au membrane.

  15. Vertically aligned nanowires on flexible silicone using a supported alumina template prepared by pulsed anodization

    DEFF Research Database (Denmark)

    Mátéfi-Tempfli, Stefan; Mátéfi-Tempfli, M.

    2009-01-01

    Carpets of vertically aligned nanowires on flexible substrates are successfully realized by a template method. Applying special pulsed anodization conditions, defect-free nanoporous alumina structures supported on polydimethylsiloxane (PDMS), a flexible silicone elastomer, are created. By using...... this template with nanopores ending on a conducting underlayer, a high-density nanowire array can be simply grown by direct DCelectrodeposition on the top of the silicone rubber....

  16. Nickel hydroxide modified electrodes for urea determination

    Directory of Open Access Journals (Sweden)

    Luiz Henrique Dall´Antonia

    2007-03-01

    Full Text Available Nickel hydroxide films were prepared by electrodeposition from a solution Ni(NO32 0,05 mol L ?¹ on ITO electrodes (Tin oxide doped with Indium on PET-like plastic film, applying a current of - 0,1 A cm ?² during different time intervals between 1800 and 7200 s. The electrochemical behavior of the nickel hydroxide electrode was investigated through a cyclic voltammogram, in NaOH 1,0 mol L ?¹, where it was observed two peaks in the profile in 0,410 and 0,280 V, corresponding to redox couple Ni(II/Ni(III. A sensor for urea presenting a satisfactory answer can be obtained when, after the deposit of the film of Ni(OH2 on the electrode of nickel, it is immersed in a solution of NaOH 1,0 mol L ?¹ and applying a potential of + 0,435 V, where the maximum of the anodic current occurs in the cyclic voltammogram. Analyzing the results it can be observed that, for a range of analite concentration between 5 to 50 m mol L ?¹, the behavior is linear and the sensibility found was of 20,3 mA cm?² (mol L?¹?¹, presenting reproducibility confirming the nickel hydroxide electrodes utilization for the determination of urea.

  17. Mixed Oxide Supported MoO3 Catalyst: Preparation, Characterization and Activities in Nitration of o-xylene

    OpenAIRE

    S.M. Kemdeo; V.S. Sapkal; G.N. Chaudhari

    2010-01-01

    TiO2-ZrO2 mixed oxide support was prepared and impregnated with 12 wt % MoO3 and calcined at various temperatures. The resultant catalyst systems were characterized by XRD, FT-IR, BET, SEM, NH3-TPD and pyridine adsorbed FT-IR methods to know the physico-chemical changes occurred in course of thermal treatment. Activities of these catalysts were tested by employing them in the nitration of o-xylene. Mostly, 500 oC calcined catalyst sample was found to be most active for nitration reactio...

  18. Mixed Oxide Supported MoO3 Catalyst: Preparation, Characterization and Activities in Nitration of o-xylene

    OpenAIRE

    S.M. Kemdeo; G.N. Chaudhari; V.S. Sapkal

    2010-01-01

    TiO2-ZrO2 mixed oxide support was prepared and impregnated with 12 wt % MoO3 and calcined at various temperatures. The resultant catalyst systems were characterized by XRD, FT-IR, BET, SEM, NH3-TPD and pyridine adsorbed FT-IR methods to know the physico-chemical changes occurred in course of thermal treatment. Activities of these catalysts were tested by employing them in the nitration of o-xylene. Mostly, 500 oC calcined catalyst sample was found to be most active for nitration reaction. Cat...

  19. Sorption of nickel on chitosan

    International Nuclear Information System (INIS)

    Pivarciova, O.; Rosskopfova, O.; Galambos, M.

    2012-01-01

    This work was focused on the study of sorption properties of nickel on chitosan. Sorption of nickel on the selected sorbents was studied by batch method. Radionuclide 63 Ni was used as a tracer. Langmuir isotherm was used for interpretation of the sorption of nickel on chitosan by varying the concentration of Ni 2 + cations in aqueous phase.

  20. Electroplated tin-nickel coatings as a replacement for nickel to eliminate nickel dermatitis

    DEFF Research Database (Denmark)

    Møller, Per; Boyce, Jan M.; Nielsen, Lars Pleth

    2013-01-01

    Nickel dermatitis (skin allergy) is a growing problem in numerous countries. The alarming frequency of sensitization to nickel especially in the US caused nickel to be selected as the "Allergen of the Year" in 2008 by the American Contact Dermatitis Society. Nickel as coating in contact with skin...... has already been regulated by the nickel EU directive [94/27/EC] since 1994. In the present contribution tin/nickel alloy coatings (66.9 wt. % Sn), electrodeposited from a chloride/fluoride containing alloy electrolyte, will be presented as an alternative for both nickel and bright chromium coatings....... The main focus will be on the corrosion properties where the following corrosion investigations will be covered; corrosion potential measurements for the different coatings, estimation of corrosion rates for materials in galvanic coupling with tin/nickel coatings, salt spray test, medical tests...

  1. Preparation of diethylene glycol monomethyl ether monolaurate catalyzed by active carbon supported KF/CaO.

    Science.gov (United States)

    Lou, Shengfeng; Jia, Lihua; Guo, Xiangfeng; Wu, Ping; Gao, Lianbing; Wang, Jianjun

    2015-01-01

    Diethylene glycol monomethyl ether monolaurate (DGMEML) was synthesized via the reaction of diethylene glycol monomethyl ether (DGME) with methyl laurate (ML) by a new solid base catalyst of KF/CaO/AC, which was prepared by impregnation method using active carbon as carrier. The catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), nitrogen physisorption-desorption and Hammett indicator methods; the effect of the mole ratio of KF to CaO, DGME to ML molar ratio, amount of catalyst, reaction time and temperature on the yield of DGMEML were studied; and the relationship between the structure of the catalyst and the yield of DGMEML was investigated. The formed KCaF3 and K2O were acting as the main active components in the catalytic transesterification; the highest yield of 96.3 % was obtained as KF-to-CaO molar ratio of 2.0, DGME to ML molar ratio of 4.0, catalyst amount of 5 wt%, and reaction time of 30 min at 75 °C; and the catalyst displayed good stability in the transesterification.

  2. Preparation of Zirconia Supported Basic Nanocatalyst: A Physicochemical and Kinetic Study of Biodiesel Production from Soybean Oil.

    Science.gov (United States)

    Patil, Pramod; Pratap, Amit

    2016-01-01

    Zirconia supported cadmium oxide basic nanocatalyst was prepared by simple co-precipitation method using aq. ammonia as precipitating reagent. The catalyst was characterised by X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy technique (TEM), Brunauer-Emmet-Teller surface area measurement (BET), temperature program desorption (TPD-CO2) etc. The transesterificaton of soybean oil with methanol into biodiesel was catalysed by employing zirconia supported nanocatalyst. Kinetics of transesterificaton of oil was studied and obeyed the pseudo first order equation. While, the activation energy (Ea) for the transesterification of oil was found to be 41.18 kJ mol(-1). The 97% yield of biodiesel was observed using 7% catalyst loading (with respect of oil), 1:40 molar ratio of oil to methanol at 135°C.

  3. Supported Pd-Au Membrane Reactor for Hydrogen Production: Membrane Preparation, Characterization and Testing

    Directory of Open Access Journals (Sweden)

    Adolfo Iulianelli

    2016-05-01

    Full Text Available A supported Pd-Au (Au 7wt% membrane was produced by electroless plating deposition. Permeation tests were performed with pure gas (H2, H2, N2, CO2, CH4 for long time operation. After around 400 h under testing, the composite Pd-Au membrane achieved steady state condition, with an H2/N2 ideal selectivity of around 500 at 420 °C and 50 kPa as transmembrane pressure, remaining stable up to 1100 h under operation. Afterwards, the membrane was allocated in a membrane reactor module for methane steam reforming reaction tests. As a preliminary application, at 420 °C, 300 kPa of reaction pressure, space velocity of 4100 h−1, 40% methane conversion and 35% hydrogen recovery were reached using a commercial Ni/Al2O3 catalyst. Unfortunately, a severe coke deposition affected irreversibly the composite membrane, determining the loss of the hydrogen permeation characteristics of the supported Pd-Au membrane.

  4. Controlled synthesis of size-tunable nickel and nickel oxide nanoparticles using water-in-oil microemulsions

    International Nuclear Information System (INIS)

    Kumar, Ajeet; Saxena, Amit; Shankar, Ravi; Mozumdar, Subho; De, Arnab

    2013-01-01

    Industrial demands have generated a growing need to synthesize pure metal and metal–oxide nanoparticles of a desired size. We report a novel and convenient method for the synthesis of spherical, size tunable, well dispersed, stable nickel and nickel oxide nanoparticles by reduction of nickel nitrate at room temperature in a TX-100/n-hexanol/cyclohexane/water system by a reverse microemulsion route. We determined that reduction with alkaline sodium borohydrate in nitrogen atmosphere leads to the formation of nickel nanoparticles, while the use of hydrazine hydrate in aerobic conditions leads to the formation of nickel oxide nanoparticles. The influence of several reaction parameters on the size of nickel and nickel oxide nanoparticles were evaluated in detail. It was found that the size can be easily controlled either by changing the molar ratio of water to surfactant or by simply altering the concentration of the reducing agent. The morphology and structure of the nanoparticles were characterized by quasi-elastic light scattering (QELS), transmission electron microscopy (TEM), x-ray diffraction (XRD), electron diffraction analysis (EDA) and energy dispersive x-ray (EDX) spectroscopy. The results show that synthesized nanoparticles are of high purity and have an average size distribution of 5–100 nm. The nanoparticles prepared by our simple methodology have been successfully used for catalyzing various chemical reactions. (paper)

  5. Study on the influence of nickel and Al{sub 2}O{sub 3} support on MoS{sub 2} as hydrodenitrogenation catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Hein, J.; Hrabar, A.; Gutierrez, O.Y.; Lercher, J.A. [Technische Univ. Muenchen, Garching (Germany). Catalysis Research Center

    2012-07-01

    Alumina-supported Mo and Ni-Mo catalysts as well as an unsupported NiMo catalyst were characterized and tested in the hydrodenitrogenation (HDN) of quinoline in the presence of dibenzothiophene (DBT). The supported catalysts had a well dispersed MoS{sub 2} phase with an average stacking degree around two and slabs length below 10 nm. The unsupported NiMo sulfide catalyst exhibited long, multistacked MoS{sub 2} slabs and contained segregated Ni{sub x}S{sub y} phases. The formation of the Ni-Mo-S phase in both Ni containing catalysts was verified by X-ray absorption spectroscopy, whereas the concentration of coordinatively unsaturated sites was higher for the supported Mo and Ni-Mo catalysts than for the unsupported one. All catalysts were active in the HDN of quinoline and hydrodesulfurization of DBT. The catalytic activity increased in the order Mo/Al{sub 2}O{sub 3} < NiMo/unsupported < Ni-Mo/Al{sub 2}O{sub 3}. Thus, the influence on the catalytic activity of the promoter metal Ni is more important than the presence of a support due to the formation of the Ni-Mo-S phase (more active than MoS{sub 2}). (orig.)

  6. Preparation and electrochemical performance of copper foam-supported amorphous silicon thin films for rechargeable lithium-ion batteries

    International Nuclear Information System (INIS)

    Li Haixia; Cheng Fangyi; Zhu Zhiqiang; Bai Hongmei; Tao Zhanliang; Chen Jun

    2011-01-01

    Research highlights: → Amorphous Si thin films have been deposited on copper foam substrate by radio-frequency (rf) magnetron sputtering. → The as-prepared Si/Cu films with interconnected 3-dimensional structure are employed as anode materials of rechargeable lithium-ion batteries, showing that the electrode properties are greatly affected by the deposition temperature. → The film electrode deposited at an optimum temperature of 300 deg. C delivers a specific capacity of ∼2900 mAh/g and a coulombic efficiency above 95% at charge/discharge current density of 0.2C after 30 cycles. → The Li + diffusion coefficiency in copper foam-supported Si thin films is determined to be 2.36 x 10 -9 cm 2 /s. → The combination of rf magnetron sputtering and cooper foam substrate is an efficient route to prepare amorphous Si films with high capacity and cyclability due to the efficient ionic diffusion and interface contact with a good conductive current collector. - Abstract: Amorphous Si thin films, which have been deposited on copper foam by radio-frequency (rf) magnetron sputtering, are employed as anode materials of rechargeable lithium-ion batteries. The morphologies and structures of the as-prepared Si thin films are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). Electrochemical performance of lithium-ion batteries with the as-prepared Si films as the anode materials is investigated by cyclic voltammetry and charge-discharge measurements. The results show that the electrode properties of the prepared amorphous Si films are greatly affected by the deposition temperature. The film electrode deposited at an optimum temperature of 300 deg. C can deliver a specific capacity of ∼2900 mAh/g and a coulombic efficiency above 95% at charge/discharge current density of 0.2C after 30 cycles. The Li + diffusion coefficiency in copper foam-supported Si thin films is determined to be 2.36 x 10 -9 cm

  7. Cadmium Sulfide and Nickel Synergetic Co-catalysts Supported on Graphitic Carbon Nitride for Visible-Light-Driven Photocatalytic Hydrogen Evolution

    Science.gov (United States)

    Yue, Xinzheng; Yi, Shasha; Wang, Runwei; Zhang, Zongtao; Qiu, Shilun

    2016-01-01

    Design and preparation of noble-metal-free photocatalysts is of great importance for photocatalytic water splitting harvesting solar energy. Here, we report the high visible-light-driven hydrogen evolution upon the hybrid photocatalyst system consisting of CdS nanocrystals and Ni@NiO nanoparticles grown on the surface of g-C3N4. The hybrid system shows a high H2-production rate of 1258.7 μmol h−1 g−1 in the presence of triethanolamine as a sacrificial electron donor under visible light irradiation. The synergetic catalytic mechanism has been studied and the results of photovoltaic and photoluminescence properties show that efficient electron transfer could be achieved from g-C3N4 to CdS nanocrystals and subsequently to Ni@NiO hybrid. PMID:26923439

  8. Cadmium Sulfide and Nickel Synergetic Co-catalysts Supported on Graphitic Carbon Nitride for Visible-Light-Driven Photocatalytic Hydrogen Evolution

    Science.gov (United States)

    Yue, Xinzheng; Yi, Shasha; Wang, Runwei; Zhang, Zongtao; Qiu, Shilun

    2016-02-01

    Design and preparation of noble-metal-free photocatalysts is of great importance for photocatalytic water splitting harvesting solar energy. Here, we report the high visible-light-driven hydrogen evolution upon the hybrid photocatalyst system consisting of CdS nanocrystals and Ni@NiO nanoparticles grown on the surface of g-C3N4. The hybrid system shows a high H2-production rate of 1258.7 μmol h-1 g-1 in the presence of triethanolamine as a sacrificial electron donor under visible light irradiation. The synergetic catalytic mechanism has been studied and the results of photovoltaic and photoluminescence properties show that efficient electron transfer could be achieved from g-C3N4 to CdS nanocrystals and subsequently to Ni@NiO hybrid.

  9. New catalyst supports prepared by surface modification of graphene- and carbon nanotube structures with nitrogen containing carbon coatings

    Science.gov (United States)

    Oh, Eun-Jin; Hempelmann, Rolf; Nica, Valentin; Radev, Ivan; Natter, Harald

    2017-02-01

    We present a new and facile method for preparation of nitrogen containing carbon coatings (NCC) on the surface of graphene- and carbon nanotubes (CNT), which has an increased electronic conductivity. The modified carbon system can be used as catalyst support for electrocatalytic applications, especially for polymer electrolyte membrane fuel cells (PEMFC). The surface modification is performed by impregnating carbon structures with a nitrogen containing ionic liquid (IL) with a defined C:N ratio, followed by a thermal treatment under ambient conditions. We investigate the influence of the main experimental parameters (IL amount, temperature, substrate morphology) on the formation of the NCC. Additionally, the structure and the chemical composition of the resulting products are analyzed by electron microscopic techniques (SEM, TEM), energy disperse X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS) and hot extraction analysis. The modified surface has a nitrogen content of 29 wt% which decreases strongly at temperatures above 600 °C. The new catalyst supports are used for the preparation of PEMFC anodes which are characterized by polarization measurements and electrochemical impedance spectroscopy (EIS). Compared to unmodified graphene and CNT samples the electronic conductivity of the modified systems is increased by a factor of 2 and shows improved mass transport properties.

  10. Synthesis of mesoporous zeolite catalysts by in situ formation of carbon template over nickel nanoparticles

    DEFF Research Database (Denmark)

    Abildstrøm, Jacob Oskar; Kegnæs, Marina; Hytoft, Glen

    2016-01-01

    A novel synthesis procedure for the preparation of the hierarchical zeolite materials with MFI structure based on the carbon templating method with in situ generated carbon template is presented in this study. Through chemical vapour deposition of coke on nickel nanoparticles supported on silica...... oxide, a carbon-silica composite is obtained and exploited as a combined carbon template/silica source for zeolite synthesis. This approach has several advantages in comparison with conventional carbon templating methods, where relatively complicated preparative strategies involving multistep...... impregnation procedures and rather expensive chemicals are used. Removal of the carbon template by combustion results in zeolite single crystals with intracrystalline pore volumes between 0.28 and 0.48 cm3/g. The prepared zeolites are characterized by XRD, SEM, TEM and physisorption analysis. The isomerization...

  11. Dynamic research on preparation of soil like substrate in bioregenerative life support system

    Science.gov (United States)

    Hu, Enzhu; Bartsev, Sergey I.; Liu, Professor Hong

    Bioregenerative life support systems(BLSS) with higher plants emerge as a promising key technology for sustainable planetary explorations. Conversion of inedible plant biomass into soil like substrate would reduce logistics and increase system closure. A mathematic model was established to simulate the dynamic behavior of this biological process, which included growth of microorganisms, growth of earthworms, and decomposition of organic substance. Meanwhile, a series of experiments using grinding wheat straw, earthworms Eisenia foetida and native bacteria were conducted to testify the validity of the model. The numerical simulation was consistent with experimental results and rightly reflected the formation mechanism of soil like substrate. The numerical methods used in this study were Runge-Kutta-Fehlberg method, interior-reflective Newton method and nonlinear least-square method.

  12. Controlled interactions between anhydrous keggin-type heteropolyacids and silica support: Preparation and characterization of well-defined silica-supported polyoxometalate species

    KAUST Repository

    Grinenval, Eva

    2010-11-11

    Anhydrous Keggin-type phosphorus heteropolyacids were deposited on partially dehydroxylated silica by using the surface organometallic chemistry (SOMC) strategy. The resulting solids were characterized by a combination of physicochemical methods including IR, Raman, 1D and 2D 1H, and 31P MAS NMR, electron microscopy experiments and density functional theory (DFT) calculations. It is shown that the main surface species is [ - Si(OH...H+)]2[H+]1[PM 12O403-] where the polyoxometalate is linked to the support by proton interaction with two silanols. Two other minor species (10% each) are formed by coordination of the polyoxometalate to the surface via the interaction between all three protons with three silanol groups or via three covalent bonds formed by dehydroxylation of the above species. Comparison of the reactivity of these solids and of compounds prepared by a classical way shows that the samples prepared by the SOMC approach contain ca. 7 times more acid sites. © 2010 American Chemical Society.

  13. The cost of nickel allergy

    DEFF Research Database (Denmark)

    Hamann, Carsten R; Hamann, Dathan; Hamann, Curtis

    2013-01-01

    %), followed by aluminium-bronze (62, 17%). In total, 239 denominations released nickel (28%). Coins from Bolivia, Brazil and Costa Rica did not release nickel. Fewer than one-third of the denominations or issues from China, India, the euro area and Indonesia released nickel. In the United States, the Russian...... Federation, Japan, and Mexico, one-third or more of the denominations released nickel. Conclusions. This worldwide selection of circulating coins covered countries with 75% of the world population, and shows that the majority of the world population lives in countries where coins release nickel. Pertinently...

  14. Decomposition of methane over alumina supported Fe and Ni–Fe bimetallic catalyst: Effect of preparation procedure and calcination temperature

    Directory of Open Access Journals (Sweden)

    A.S. Al-Fatesh

    2018-02-01

    Full Text Available Catalytic decomposition of methane has been studied extensively as the production of hydrogen and formation of carbon nanotube is proven crucial from the scientific and technological point of view. In that context, variation of catalyst preparation procedure, calcination temperature and use of promoters could significantly alter the methane conversion, hydrogen yield and morphology of carbon nanotubes formed after the reaction. In this work, Ni promoted and unpromoted Fe/Al2O3 catalysts have been prepared by impregnation, sol–gel and co-precipitation method with calcination at two different temperatures. The catalysts were characterized by X-ray diffraction (XRD, N2 physisorption, temperature programmed reduction (TPR and thermogravimetric analysis (TGA techniques. The catalytic activity was tested for methane decomposition reaction. The catalytic activity was high when calcined at 500 °C temperature irrespective of the preparation method. However while calcined at high temperature the catalyst prepared by impregnation method showed a high activity. It is found from XRD and TPR characterization that disordered iron oxides supported on alumina play an important role for dissociative chemisorptions of methane generating molecular hydrogen. The transmission electron microscope technique results of the spent catalysts showed the formation of carbon nanotube which is having length of 32–34 nm. The Fe nanoparticles are present on the tip of the carbon nanotube and nanotube grows by contraction–elongation mechanism. Among three different methodologies impregnation method was more effective to generate adequate active sites in the catalyst surface. The Ni promotion enhances the reducibility of Fe/Al2O3 oxides showing a higher catalytic activity. The catalyst is stable up to six hours on stream as observed in the activity results.

  15. Review of Supported Pd-Based Membranes Preparation by Electroless Plating for Ultra-Pure Hydrogen Production

    Directory of Open Access Journals (Sweden)

    David Alique

    2018-01-01

    Full Text Available In the last years, hydrogen has been considered as a promising energy vector for the oncoming modification of the current energy sector, mainly based on fossil fuels. Hydrogen can be produced from water with no significant pollutant emissions but in the nearest future its production from different hydrocarbon raw materials by thermochemical processes seems to be more feasible. In any case, a mixture of gaseous compounds containing hydrogen is produced, so a further purification step is needed to purify the hydrogen up to required levels accordingly to the final application, i.e., PEM fuel cells. In this mean, membrane technology is one of the available separation options, providing an efficient solution at reasonable cost. Particularly, dense palladium-based membranes have been proposed as an ideal chance in hydrogen purification due to the nearly complete hydrogen selectivity (ideally 100%, high thermal stability and mechanical resistance. Moreover, these membranes can be used in a membrane reactor, offering the possibility to combine both the chemical reaction for hydrogen production and the purification step in a unique device. There are many papers in the literature regarding the preparation of Pd-based membranes, trying to improve the properties of these materials in terms of permeability, thermal and mechanical resistance, poisoning and cost-efficiency. In this review, the most relevant advances in the preparation of supported Pd-based membranes for hydrogen production in recent years are presented. The work is mainly focused in the incorporation of the hydrogen selective layer (palladium or palladium-based alloy by the electroless plating, since it is one of the most promising alternatives for a real industrial application of these membranes. The information is organized in different sections including: (i a general introduction; (ii raw commercial and modified membrane supports; (iii metal deposition insights by electroless-plating; (iv

  16. Review of Supported Pd-Based Membranes Preparation by Electroless Plating for Ultra-Pure Hydrogen Production

    Science.gov (United States)

    Alique, David; Martinez-Diaz, David; Sanz, Raul

    2018-01-01

    In the last years, hydrogen has been considered as a promising energy vector for the oncoming modification of the current energy sector, mainly based on fossil fuels. Hydrogen can be produced from water with no significant pollutant emissions but in the nearest future its production from different hydrocarbon raw materials by thermochemical processes seems to be more feasible. In any case, a mixture of gaseous compounds containing hydrogen is produced, so a further purification step is needed to purify the hydrogen up to required levels accordingly to the final application, i.e., PEM fuel cells. In this mean, membrane technology is one of the available separation options, providing an efficient solution at reasonable cost. Particularly, dense palladium-based membranes have been proposed as an ideal chance in hydrogen purification due to the nearly complete hydrogen selectivity (ideally 100%), high thermal stability and mechanical resistance. Moreover, these membranes can be used in a membrane reactor, offering the possibility to combine both the chemical reaction for hydrogen production and the purification step in a unique device. There are many papers in the literature regarding the preparation of Pd-based membranes, trying to improve the properties of these materials in terms of permeability, thermal and mechanical resistance, poisoning and cost-efficiency. In this review, the most relevant advances in the preparation of supported Pd-based membranes for hydrogen production in recent years are presented. The work is mainly focused in the incorporation of the hydrogen selective layer (palladium or palladium-based alloy) by the electroless plating, since it is one of the most promising alternatives for a real industrial application of these membranes. The information is organized in different sections including: (i) a general introduction; (ii) raw commercial and modified membrane supports; (iii) metal deposition insights by electroless-plating; (iv) trends in

  17. Review of Supported Pd-Based Membranes Preparation by Electroless Plating for Ultra-Pure Hydrogen Production.

    Science.gov (United States)

    Alique, David; Martinez-Diaz, David; Sanz, Raul; Calles, Jose A

    2018-01-23

    In the last years, hydrogen has been considered as a promising energy vector for the oncoming modification of the current energy sector, mainly based on fossil fuels. Hydrogen can be produced from water with no significant pollutant emissions but in the nearest future its production from different hydrocarbon raw materials by thermochemical processes seems to be more feasible. In any case, a mixture of gaseous compounds containing hydrogen is produced, so a further purification step is needed to purify the hydrogen up to required levels accordingly to the final application, i.e., PEM fuel cells. In this mean, membrane technology is one of the available separation options, providing an efficient solution at reasonable cost. Particularly, dense palladium-based membranes have been proposed as an ideal chance in hydrogen purification due to the nearly complete hydrogen selectivity (ideally 100%), high thermal stability and mechanical resistance. Moreover, these membranes can be used in a membrane reactor, offering the possibility to combine both the chemical reaction for hydrogen production and the purification step in a unique device. There are many papers in the literature regarding the preparation of Pd-based membranes, trying to improve the properties of these materials in terms of permeability, thermal and mechanical resistance, poisoning and cost-efficiency. In this review, the most relevant advances in the preparation of supported Pd-based membranes for hydrogen production in recent years are presented. The work is mainly focused in the incorporation of the hydrogen selective layer (palladium or palladium-based alloy) by the electroless plating, since it is one of the most promising alternatives for a real industrial application of these membranes. The information is organized in different sections including: (i) a general introduction; (ii) raw commercial and modified membrane supports; (iii) metal deposition insights by electroless-plating; (iv) trends in

  18. Fundamentals of Melt infiltration for the Preparation of Supported Metal Catalysts.The Case of Co/SiO2 Fischer-Tropsch Synthesis

    NARCIS (Netherlands)

    Eggenhuisen, T.M.|info:eu-repo/dai/nl/313959498; den Breejen, J.P.|info:eu-repo/dai/nl/304837318; Verdoes, D.; de Jongh, P.E.|info:eu-repo/dai/nl/186125372; de Jong, K.P.|info:eu-repo/dai/nl/06885580X

    2013-01-01

    We explored melt infiltration of mesoporous silica supports to prepare supported metal catalysts with high loadings and controllable particle sizes. Melting of Co(NO3)2 ·6H2O in the presence of silica supports was studied in situ with differential scanning calorimetry. The melting point depression

  19. Synthesis and characterization of alumina-supported vanadium oxide catalysts prepared by the molecular designed dispersion of VO(acac)2 complexes

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Baltes, M.; Voort, P. van der; Ramachandra Rao, R.; Catana, Gabriela; Schoonheydt, R.A.; Vansant, E.F.

    2000-01-01

    Alumina-supported vanadium oxide catalysts have been prepared by the molecular designed dispersion method, using the vanadyl acetylacetonate complex (VO(acac)2). The complex has been adsorbed on the support from solution, followed by thermal conversion into the corresponding supported vanadium oxide

  20. Nickel in tap water

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Nielsen, G D; Flyvholm, Morten

    1983-01-01

    Nickel analyses of tap water from several sources in Copenhagen gave up to 490 X 10(-6) g X 1(-1) in the first 250 ml portions. Hot water gave higher values than cold water. After flushing for 5 min, low values were found. Considerable variation from time to time and from tap to tap was found...

  1. EPIDEMIOLOGICAL AND PATHOGENETIC ASPECTS OF NICKEL POISONING

    OpenAIRE

    Vladmila Bojanic; Vladimir Ilic; Biljana Jovic

    2007-01-01

    Nickel is widely distributed in the environment. High consumption of nickel containing products inevitably leads to environmental pollution by nickel and its derivatives at all stages of production, utilization, and disposal.Human exposure to nickel occurs primarily via inhalation and ingestion and is particularly high among nickel metallurgy workers. In addition, implantation of nickel-containing endoprostheses and iatrogenic administration of nickel-contaminated medica-tions leads to signif...

  2. Research, development, and demonstration of nickel-zinc batteries for electric vehicle propulsion. Annual report for 1980

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    Progress in the development of nickel-zinc batteries for electric vehicles is reported. Information is presented on nickel electrode preparation and testing; zinc electrode preparation with additives and test results; separator development and the evaluation of polymer-blend separator films; sealed Ni-Zn cells; and the optimization of electric vehicle-type Ni-Zn cells. (LCL)

  3. Homocoupling of benzyl halides catalyzed by POCOP-nickel pincer complexes

    KAUST Repository

    Chen, Tao

    2012-08-01

    Two types of POCOP-nickel(II) pincer complexes were prepared by mixing POCOP pincer ligands and NiX 2 in toluene at reflux. The resulting nickel complexes efficiently catalyze the homocoupling reactions of benzyl halides in the presence of zinc. The coupled products were obtained in excellent to quantitative yields. © 2012 Elsevier Ltd. All rights reserved.

  4. Effect of nickel content on the anodic dissolution and passivation of ...

    Indian Academy of Sciences (India)

    Nickel and its alloys exhibited excellent corrosion resistance in aqueous aggressive environments, which are attributed to the ability of nickel to form a stable passive film on its surface.24–33. In recent years, several attempts have been made at prepar- ing zinc coating with high corrosion resistance. In so doing, zinc alloys ...

  5. Syntheses and spectroscopic properties of mercury(II) and nickel(II ...

    African Journals Online (AJOL)

    Mercury(II) complex, [Hg2(BPTU-2H)Cl2] and nickel(II) complex, [Ni(BPTU-H)2] were prepared by reacting Bis(N-phenylthiourea), BPTU, with mercury(II) chloride and nickel(II) acetate respectively. The complexes were characterized by IR, diffuse reflectance, 1H NMR spectra and elemental analysis. BPTU acts as ...

  6. Leukopak PBMC sample processing for preparing quality control material to support proficiency testing programs.

    Science.gov (United States)

    Garcia, Ambrosia; Keinonen, Sarah; Sanchez, Ana M; Ferrari, Guido; Denny, Thomas N; Moody, M Anthony

    2014-07-01

    External proficiency testing programs designed to evaluate the performance of end-point laboratories involved in vaccine and therapeutic clinical trials form an important part of clinical trial quality assurance. Good clinical laboratory practice (GCLP) guidelines recommend both assay validation and proficiency testing for assays being used in clinical trials, and such testing is facilitated by the availability of large numbers of well-characterized test samples. These samples can be distributed to laboratories participating in these programs and allow monitoring of laboratory performance over time and among participating sites when results are obtained with samples derived from a large master set. The leukapheresis procedure provides an ideal way to collect samples from participants that can meet the required number of cells to support these activities. The collection and processing of leukapheresis samples require tight coordination between the clinical and laboratory teams to collect, process, and cryopreserve large number of samples within the established ideal time of ≤8 hours. Here, we describe our experience with a leukapheresis cryopreseration program that has been able to preserve the functionality of cellular subsets and that provides the sample numbers necessary to run an external proficiency testing program. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Preparation and characterization of Pt supported on graphene with enhanced electrocatalytic activity in fuel cell

    Science.gov (United States)

    Xin, Yuchen; Liu, Jian-guo; Zhou, Yong; Liu, Wenming; Gao, Jian; Xie, Yun; Yin, Ying; Zou, Zhigang

    Pt nanoparticles are deposited onto graphene sheets via synchronous reduction of H 2PtCl 6 and graphene oxide (GO) suspension using NaBH 4. Lyophilization is introduced to avoid irreversible aggregation of graphene (G) sheets, which happens during conventional drying process. Pt/G catalysts reveal a high catalytic activity for both methanol oxidation and oxygen reduction reaction compared to Pt supported on carbon black (Pt/C). The performance of Pt/G catalysts is further improved after heat treatment in N 2 atmosphere at 300 °C for 2 h, and the peak current density of methanol oxidation for Pt/G after heat treatment is almost 3.5 times higher than Pt/C. Transmission electron microscope (TEM) images show that the Pt particles are uniformly distributed on graphene sheets. X-ray photoelectron spectroscopy (XPS) results demonstrate that the interaction between Pt and graphene is enhanced during annealing. It suggests that graphene has provided a new way to improve electrocatalytic activity of catalyst for fuel cell.

  8. Preparation and Characterization of Cellulose Triacetate as Support for Lecitase Ultra Immobilization

    Directory of Open Access Journals (Sweden)

    Francielle Batista da Silva

    2017-11-01

    Full Text Available The use of polymers as supports for enzyme immobilization is a strategy that enables to remove the enzymes from a chemical reaction and improve their efficiency in catalytic processes. In this work, cellulose triacetate (CTA was used for physical adsorption of phospholipase Lecitase ultra (LU. CTA is more hydrophobic than cellulose, shows good performance in the lipases immobilization being a good candidate for immobilization of phospholipases. We investigated the immobilization of LU in CTA, the stability of the immobilized enzyme (CTA-LU and the performance of CTA-LU using soybean oil as a substrate. LU was efficiently immobilized in CTA reaching 97.1% in 60 min of contact with an enzymatic activity of 975.8 U·g−1. The CTA-LU system presents good thermal stability, being superior of the free enzyme and increase of the catalytic activity in the whole range of pH values. The difference observed for immobilized enzyme compared to free one occurs because of the interaction between the enzyme and the polymer, which stabilizes the enzyme. The CTA-LU system was used in the transesterification of soybean oil with methanol, with the production of fatty acid methyl esters. The results showed that CTA-LU is a promising system for enzymatic reactions.

  9. Preparation and Characterization of a Hydrophobic Metal-Organic Framework Membrane Supported on Thin Porous Metal Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jian; Canfield, Nathan L.; Liu, Wei

    2016-02-29

    A hydrophobic metal-organic framework (MOF) UiO-66-CH3 is prepared and its solvothermal stability is investigated in comparison to UiO-66. It is confirmed that the MOF stability is enhanced by introduction of the two methyl groups, while the water adsorption is reduced. Given its hydrophobicity and stability, UiO-66-CH3 is proposed as an attractive membrane material for gas separation under moisture conditions. The UiO-66-CH3 membrane is prepared on a 50µm-thin porous Ni support sheet for the first time by use of a secondary growth method. It is found that uniform seed coating on the support is necessary to form a continuous membrane. In addition to growth time and temperature, presence of a modulator in the growth solution is found to be useful for controlling hydrothermal membrane growth on the seeded support. A dense, inter-grown membrane layer is formed by 24-h growth over a temperature range from 120 oC to 160 oC. The membrane surface comprises 500 nm octahedral crystals, which are supposed to grow out of the original 100 nm spherical seeding crystals. The separation characteristics of resulting membranes are tested with pure CO2, air, CO2/air mixture, and humid CO2/air mixture. CO2 permeance as high as 1.9E-06 mol/m2/s/Pa at 31oC is obtained. Unlike the hydrophilic zeolite membranes, CO2 permeation through this membrane is not blocked by the presence of water vapor in the feed gas. The results suggest that this MOF framework is a promising membrane material worth to be further investigated for separation of CO2 and other small molecules from humid gas mixtures.

  10. Correction: Particle shape optimization by changing from an isotropic to an anisotropic nanostructure: preparation of highly active and stable supported Pt catalysts in microemulsions.

    Science.gov (United States)

    Parapat, Riny Y; Wijaya, Muliany; Schwarze, Michael; Selve, Sören; Willinger, Marc; Schomäcker, Reinhard

    2016-04-07

    Correction for 'Particle shape optimization by changing from an isotropic to an anisotropic nanostructure: preparation of highly active and stable supported Pt catalysts in microemulsions' by Riny Y. Parapat et al., Nanoscale, 2013, 5, 796-805.

  11. Influence of coprecipitation and mechanical mixture methods on the characteristics of nickel oxide-alumina composites; Influencia dos metodos de coprecipitacao e mistura mecanica nas caracteristicas de compositos oxido de niquel-alumina

    Energy Technology Data Exchange (ETDEWEB)

    Cordeiro, G.L.; Yoshito, W.K.; Ussui, V.; Lima, N.B. de; Lazar, D.R.R., E-mail: gcordeiro@usp.br [Instituto de Pesquisas Energeticas e Nucleares (CCTM/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia de Materiais

    2014-07-01

    Alumina-supported nickel catalysts are currently used in the reforming process due to low cost and high activity for hydrogen production from alcohols. In this work, the effect of preparation methods on nickel oxide-alumina based materials has been investigated. Nickel content was fixed at 15 wt%. Ceramic powders were obtained by coprecipitation in ammonia medium and mechanical mixture. Coprecipitated materials were calcined in air at 750 deg C to obtain the corresponding oxides. Materials obtained by mechanical mixture were prepared by wet milling of nickel oxide and alumina powders, both synthesized by precipitation and calcination in air at 450 and 750 deg C, respectively. Powders were characterized by X-ray diffraction, nitrogen gas sorption by applying the BET method, laser diffraction, scanning electron microscopy, electrophoretic mobility measurements for zeta potential determination and infrared spectroscopy. The results showed that coprecipitation method allowed the production of mixed oxides with high surface area (232,7 ± 3,2 m{sup 2}.g{sup -1}) and normal granulometric distribution while mechanical mixture led to the formation of materials constituted by gamma alumina and nickel oxide phases, with low surface area (136,2 ± 0,5 m{sup 2}.g{sup -1}) and bimodal granulometric distribution. (author)

  12. Preparation of Metal Nanoparticles via Sonochemical Reduction

    OpenAIRE

    Saura Puig, Oriol

    2011-01-01

    Pure nickel, copper and zinc nanoparticles were prepared from chlorides of these elements using ultrasound with three different reducing agents (zinc, aluminum and magnesium). In the second part, syntheses of nickel-copper alloy and nickel-zinc using ultrasound were investigated. The products were characterized by powder X-ray diffraction. The reaction parameters, such as sonification time, the amount of reagents and reaction conditions were modified to observe variations in...

  13. Nickel compounds induce histone ubiquitination by inhibiting histone deubiquitinating enzyme activity

    International Nuclear Information System (INIS)

    Ke Qingdong; Ellen, Thomas P.; Costa, Max

    2008-01-01

    Nickel (Ni) compounds are known carcinogens but underlying mechanisms are not clear. Epigenetic changes are likely to play an important role in nickel ion carcinogenesis. Previous studies have shown epigenetic effects of nickel ions, including the loss of histone acetylation and a pronounced increase in dimethylated H3K9 in nickel-exposed cells. In this study, we demonstrated that both water-soluble and insoluble nickel compounds induce histone ubiquitination (uH2A and uH2B) in a variety of cell lines. Investigations of the mechanism by which nickel increases histone ubiquitination in cells reveal that nickel does not affect cellular levels of the substrates of this modification, i.e., ubiquitin, histones, and other non-histone ubiquitinated proteins. In vitro ubiquitination and deubiquitination assays have been developed to further investigate possible effects of nickel on enzymes responsible for histone ubiquitination. Results from the in vitro assays demonstrate that the presence of nickel did not affect the levels of ubiquitinated histones in the ubiquitinating assay. Instead, the addition of nickel significantly prevents loss of uH2A and uH2B in the deubiquitinating assay, suggesting that nickel-induced histone ubiquitination is the result of inhibition of (a) putative deubiquitinating enzyme(s). Additional supporting evidence comes from the comparison of the response to nickel ions with a known deubiquitinating enzyme inhibitor, iodoacetamide (IAA). This study is the first to demonstrate such effects of nickel ions on histone ubiquitination. It also sheds light on the possible mechanisms involved in altering the steady state of this modification. The study provides further evidence that supports the notion that nickel ions alter epigenetic homeostasis in cells, which may lead to altered programs of gene expression and carcinogenesis

  14. Distorted tetrahedral nickel-nitrosyl complexes: spectroscopic characterization and electronic structure.

    Science.gov (United States)

    Soma, Shoko; Van Stappen, Casey; Kiss, Mercedesz; Szilagyi, Robert K; Lehnert, Nicolai; Fujisawa, Kiyoshi

    2016-09-01

    The linear nickel-nitrosyl complex [Ni(NO)(L3)] supported by a highly hindered tridentate nitrogen-based ligand, hydrotris(3-tertiary butyl-5-isopropyl-1-pyrazolyl)borate (denoted as L3), was prepared by the reaction of the potassium salt of the ligand with the nickel-nitrosyl precursor [Ni(NO)(Br)(PPh 3 ) 2 ]. The obtained nitrosyl complexes as well as the corresponding chlorido complexes [Ni(NO)(Cl)(PPh 3 ) 2 ] and [Ni(Cl)(L3)] were characterized by X-ray crystallography and different spectroscopic methods including IR/far-IR, UV-Vis, NMR, and multi-edge X-ray absorption spectroscopy at the Ni K-, Ni L-, Cl K-, and P K-edges. For comparative electronic structure analysis we also performed DFT calculations to further elucidate the electronic structure of [Ni(NO)(L3)]. These results provide the nickel oxidation state and the character of the Ni-NO bond. The complex [Ni(NO)(L3)] is best described as [Ni (II) (NO (-) )(L3)], and the spectroscopic results indicate that the phosphane complexes have a similar [Ni (II) (NO (-) )(X)(PPh 3 ) 2 ] ground state.

  15. Orientation-dependent electromagnetic properties of basalt fibre/nickel core–shell heterostructures

    International Nuclear Information System (INIS)

    Yu-Qing, Kang; Mao-Sheng, Cao; Xiao-Yong, Fang; Jie, Yuan

    2010-01-01

    The influence of orientation on electromagnetic properties of basalt fibre/nickel core–shell heterostructures prepared by a simple electroless plating method is investigated. For comparison, the same investigation is also performed on naked basalt fibres. For electromagnetic measurement, the directions of basalt fibre/nickel and naked basalt fibres are parallel, random and perpendicular to the direction of external electric field, termed E || sample, random sample and E p erpendicular sample, respectively. Electromagnetic anisotropy can be clearly observed in the basalt fibre/nickel core–shell heterostructures, while electromagnetic properties of naked basalt fibres are unrelated to the orientation. The E p erpendicular basalt fibre/nickel shows the highest dielectric loss but the lowest magnetic loss, and E || basalt fibre/nickel exhibits the highest magnetic loss but the lowest dielectric loss. The dielectric loss of E p erpendicular basalt fibre/nickel is several times as large as that of E || basalt fibre/nickel, which could be attributed to the increase of polarization relaxation time as a consequence of the nanosize-confinement effect. The magnetic loss of E || basalt fibre/nickel is even one order of magnitude higher than that of E p erpendicular basalt fibre/nickel, which originates mainly from the natural magnetic resonance of basalt fibre/nickel core–shell heterostructures. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  16. A Study On Dispersion Stability Of Nickel Nanoparticles Synthesized By Wire Explosion In Liquid Media

    Directory of Open Access Journals (Sweden)

    Kim C.K.

    2015-06-01

    Full Text Available In this study, nickel nanoparticles were synthesized in ethanol using portable pulsed wire evaporation, which is a one-step physical method. From transmission electron microscopy images, it was found that the Ni nanoparticles exhibited a spherical shape with an average diameter of 7.3 nm. To prevent aggregation of the nickel nanoparticles, a polymer surfactant was added into the ethanol before the synthesis of nickel nanoparticles, and adsorbed on the freshly synthesized nickel nanoparticles during the wire explosion. The dispersion stability of the prepared nickel nanofluids was investigated by zeta-potential analyzer and Turbiscan optical analyzer. As a result, the optimum concentration of polymer surfactant to be added was suggested for the maximized dispersion stability of the nickel nanofluids.

  17. Nickel oxide/hydroxide nanoplatelets synthesized by chemical precipitation for electrochemical capacitors

    International Nuclear Information System (INIS)

    Wu, M.-S.; Hsieh, H.-H.

    2008-01-01

    Nickel hydroxide powder prepared by directly chemical precipitation method at room temperature has a nanoplatelet-like morphology and could be converted into nickel oxide at annealing temperature higher than 300 deg. C, confirmed by the thermal gravimetric analysis and X-ray diffraction. Annealing temperature influences significantly both the electrical conductivity and the specific surface area of nickel oxide/hydroxide powder, and consequently determines the capacitor behavior. Electrochemical capacitive behavior of the synthesized nickel hydroxide/oxide film is investigated by cyclic voltammetry and electrochemical impedance spectroscope methods. After 300 deg. C annealing, the highest specific capacitance of 108 F g -1 is obtained at scan rate of 10 mV s -1 . When annealing temperature is lower than 300 deg. C, the electrical conductivity of nickel hydroxide dominates primarily the capacitive behavior. When annealing temperature is higher than 300 deg. C, both electrical conductivity and specific surface area of the nickel oxide dominate the capacitive behavior

  18. Carbon deposition on nickel ferrites and nickel-magnetite surfaces

    International Nuclear Information System (INIS)

    Allen, G.C.; Jutson, J.A.

    1988-06-01

    Carbon deposition on Commercial Advanced Gas-Cooled Reactor (CAGR) fuel cladding and heat exchanger surfaces lowers heat transfer efficiency and increases fuel pin temperatures. Several types of deposit have been identified including both thin dense layers and also low density columnar deposits with filamentary or convoluted laminar structure. The low-density types are often associated with particles containing iron, nickel or manganese. To identify the role of nickel in the deposition process surfaces composed of nickel-iron spinels or metallic nickel/magnetite mixtures have been exposed to γ radiation in a gas environment simulating that in the reactor. Examination of these surfaces by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) have shown that while metallic nickel (Ni(O)) catalyses the formation of filamentary low density carbon deposits, the presence of divalent nickel (Ni(II)) sites in spinel type oxides is associated only with dense deposits. (author)

  19. Children with social and emotional difficulties need support from a range of professionals: Preparing professions for integrated working

    Directory of Open Access Journals (Sweden)

    Lesley A Hughes

    2012-11-01

    Full Text Available Inclusive education for all children means that teachers are increasingly faced with challenges in managing children with social, emotional and behavioural difficulties (SEBD whose complex needs span a number of professional disciplines, some of which sit outside of education. However, whilst it is recognised that children with SEBD require management and support across a range of professions that include education, health, social and youth services, there is little done to prepare teaching staff for working across professional and organisational boundaries. The evidence of poor communication and team working amongst professions has led to policy changes and guidelines calling for greater coordination in the delivery of services for children and young people. This paper considers how education and training needs to prepare students with the knowledge and skills for collaborative working through interprofessional education (IPE, and draws on adult learning theory and activity theory to frame its direction. In doing so, it demonstrates a model for IPE that can be used to engage students from different disciplines to gain insight into the understanding of the wider issues of SEBD and the roles and responsibilities of the other professions involved. The model is one that enables students to consider the impact the role of others has on their own role, and to reflect on how their role impacts on the role of others.

  20. Decreasing heavy metals content in aqueous solutions using prepared polyacrylonitrile (PAN)-supported Titanium Silicate; equilibrium studies

    International Nuclear Information System (INIS)

    EI-Zahhal, A.A.

    2007-01-01

    Equilibrium and kinetic studies was performed on sorption of heavy metal ions (Pb(II), Cr(lII) and Zn(II) on unsupported and polyacrylonitrile (PAN) supported amorphous titanium silicate. The sorbents was prepared and characterized, then used for sorption of metal ions. Different factors affecting the sorption equilibrium (ph, ion concentration, contact time, and competitive sorption) were studied. The descending order of metal ion uptake is as Pb(II) > Cr(III) > Zn(lI). The competitive sorption clarify the high affinity of the resins towards Pb(II). The most common models for sorption (Langumir and Freundlish) were used for studying the sorption of heavy metal ions and their constants were assigned

  1. Distribution of nickel between copper-nickel and alumina saturated iron silicate slags

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, R.G.; Acholonu, C.C.

    1984-03-01

    The solubility of nickel in slag is determined in this article by equilibrating copper-nickel alloys with alumina-saturated iron silicate slags in an alumina crucible at 1573 K. The results showed that nickel dissolves in slag both as nickel oxide and as nickel metal. The presence of alumina is shown to increase the solubility of nickel in slags.

  2. Mixed Oxide Supported MoO3 Catalyst: Preparation, Characterization and Activities in Nitration of o-xylene

    Directory of Open Access Journals (Sweden)

    S.M. Kemdeo

    2010-10-01

    Full Text Available TiO2-ZrO2 mixed oxide support was prepared and impregnated with 12 wt % MoO3 and calcined at various temperatures. The resultant catalyst systems were characterized by XRD, FT-IR, BET, SEM, NH3-TPD and pyridine adsorbed FT-IR methods to know the physico-chemical changes occurred in course of thermal treatment. Activities of these catalysts were tested by employing them in the nitration of o-xylene. Mostly, 500 oC calcined catalyst sample was found to be most active for nitration reaction. Catalyst calcined at higher temperatures showed the negative influence on o-xylene conversion and 4-nitro-o-xylene selectivity. Conversion can be correlated with the presence of strong Brönsted acid sites over the catalyst surface whereas change in selectivity was found attributed to the pore diameter of the catalyst. These catalysts also performed satisfactorily, when used for nitration of other aromatics. No use of corrosive sulfuric acid and efficient reusability of the catalyst make the process environmentally friendly and economic. ©2010 BCREC UNDIP. All rights reserved(Received: 9th February 2010, Revised: 5th March 2010; Accepted: 18th March 2010[How to Cite: S.M. Kemdeo, V.S. Sapkal, G.N. Chaudhari. (2010. Mixed Oxide Supported MoO3 Catalyst: Preparation, Characterization and Activities in Nitration of o-xylene. Bulletin of Chemical Reaction Engineering and Catalysis, 5(1: 39-49. doi:10.9767/bcrec.5.1.7126.39-49][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.5.1.7126.39-49 || or local:  http://ejournal.undip.ac.id/index.php/bcrec/article/view/7126 ]Cited by in: Taylor Francis |

  3. Nickel ferrule applicators: a source of nickel exposure in children.

    Science.gov (United States)

    Jacob, Sharon E; Silverberg, Jonathan I; Rizk, Christopher; Silverberg, Nanette

    2015-01-01

    Eye makeup has been investigated for nickel content and found to have no direct association with nickel allergy and cosmetic dermatitis. However, the tools used (e.g., eyelash curlers, hairdressing scissors, hair curlers, and eye shadow and makeup applicators) may be sources. Nickel is ubiquitous and a wide range of sources have been reported, and makeup applicators (ferrules) now join the list. © 2015 Wiley Periodicals, Inc.

  4. In situ XAFS studies of the oxygen reduction reaction on carbon supported platinum and platinum nickel nano-scale alloys as cathode catalysts in fuel cells

    Science.gov (United States)

    Jia, Qingying

    Platinum based bimetallic alloys have been investigated by conducting Pt L3 and Ni K edge in situ XAFS measurements on carbon supported Pt and PtNi(1:1) nanoscale catalysts under a wide range of operating potentials. We observed that (1) the Pt-Pt bond distance in PtNi alloys is shorter than that of Pt, and the bond distance between Pt and oxygen adsorbate is longer for PtNi. (2) Pt has a tendency to stay on the surface while Ni is mostly underneath the surface. (3) While a change in oxidation of pure Pt was clearly observed at different potentials, the Pt in the PtNi alloy remained nearly oxygen-free at all potentials, but an accompanying oxidation change of Ni was observed instead. (4) PtNi has higher open circuit voltage than Pt/C. These results indicate that the chemisorption energy between Pt and oxygen adsorbate is reduced in PtNi alloys, which prevents the poison of oxygen adsorbate and hence improves the reactivity. In addition, the strain and ligand effects in PtNi nanoparticle alloys were studied by FEW calculations using experimental data as a guide to understand the factors causing the reduction of chemisorptions energy of Pt. Our calculation indicates that Pt d-band is broader and lower in energy when the bond distance between Pt is shorter, resulting in weaker chemisorption energy between Pt and absorbed oxygen atom on top, and vice verse. Meanwhile, the investigation of ligand effect shows two trends in modifying Pt's properties within alloyed transition metals. The strain effect dominates in PtNi bimetallic system, corresponding to weaker chemisorptions energy and lower white intensity of Pt L3 edge, which is in consistent with our experimental results. The implications of these results afford a good guideline in understanding the reactivity enhancement mechanism and in the context of alloy catalysts design.

  5. Pulse Reversal Plating of Nickel and Nickel Alloys for MEMS

    DEFF Research Database (Denmark)

    Tang, Peter Torben

    2001-01-01

    Pulse plating has previously been reported to improve the properties of nickel and nickel alloy deposits. Typically, focus has been on properties such as grain size, hardness and smoothness. When pulse plating is to be utilized for micro electromechanical systems (MEMS), internal stress and mater......Pulse plating has previously been reported to improve the properties of nickel and nickel alloy deposits. Typically, focus has been on properties such as grain size, hardness and smoothness. When pulse plating is to be utilized for micro electromechanical systems (MEMS), internal stress...

  6. Studying nursing in a rural setting: are students adequately supported and prepared for rural practice? A pilot study.

    Science.gov (United States)

    Gum, L F

    2007-01-01

    A rural nursing program has a vital role in improving the recruitment and retention of nurses in rural and remote settings. A small pilot study was conducted to explore the views and experiences of the first cohort of undergraduate nursing students who completed a rurally based bachelor of nursing program which commenced in 2002 in Renmark, South Australia. The participants were eight current undergraduate nursing students who were part of the first cohort of nursing students nearing completion of the program. The pilot study set out to explore support provided to rural nursing students studying in a rural setting; to investigate whether rural nursing students feel adequately prepared for rural clinical practice near completion of the nursing program; to identify the challenges and highlights of studying rurally; and to explore the probability of retention and recruitment of future nursing graduates in a rural setting. The method used was a descriptive, exploratory, web-based survey. Quantitative data were limited to descriptive statistics of demographic characteristics, career goals, graduate nurse program and future employment intentions, level of support, preparation for practice, challenges and highlights of rural study and clinical placements. Qualitative responses to open-ended questions were content analysed to identify common themes. This study found between two and four participants indicated they received no support from academic, administrative staff and clinical facilitators from the city campus. Five participants (63%) indicated they received no financial support during their studies. Seven of the participants (88%) surveyed, indicated an intention to undertake a graduate nurse program and the same number indicated they would be living in a rural or remote area in 5 years time. Six participants (75%) indicated they were prepared with regard to their 'attitude' towards their future practice as a registered nurse. The study identified some of the

  7. NICKEL ALLERGY: Surgeons Beware.

    Science.gov (United States)

    Axe, Jeremie M; Sinz, Nathan J; Axe, Michael J

    2015-06-01

    When performing an orthopaedic device implantation, it should be routine practice for the surgeon to ask the patient if he or she has a metal allergy, and more specifically a nickel allergy. Ask the patient about costume jewelry or button reactions. If it is an elective surgery, obtain a confirmatory test with the aid of a dermatologist or allergist. It is recommended to use a non-nickel implant if the surgery is urgent, the patient has a confirmed allergy, or the patient does not want to undergo testing, as these implants are readily available in 2015. Finally, if the patient has a painful joint arthroplasty and all other causes have been ruled out, order a metal allergy test to aid in diagnosis.

  8. Radiosensitization by nickel lapachol.

    Science.gov (United States)

    Skov, K A; Adomat, H; Farrell, N P

    1993-12-01

    The properties of interest in the radiosensitization of a metal complex, nickel lapachol, are compared with those of the 2-nitroimidazole, misonidazole. These very different compounds were found to be surprisingly similar in terms of their reduction potential (-370 mV), enhancement ratios for killing of hypoxic Chinese hamster ovary cells by X-irradiation, and enhancement of DNA breaks in hypoxia. For nitroimidazoles, the sensitization depends on 'electron affinity', reduction of the nitro group; for nickel lapachol it is the metal which is necessary for reduction, yet the sensitization efficiencies are remarkably close. However, the metal complex has additional activities (some sensitization in aerobic cells; increased sensitization with preincubation) which are as yet unexplained but are assumed to be related to the nature of the naphthoquinone ligand, rather than to the reduction of the metal.

  9. Radiosensitization by nickel lapachol

    Energy Technology Data Exchange (ETDEWEB)

    Skov, K.A.; Adomat, H. (B.C. Cancer Research Centre, Vancouver, BC (Canada)); Farrell, N.P. (Vermont Univ., Burlington, VT (United States). Dept. of Chemistry)

    1993-12-01

    The properties of interest in the radiosensitization of a metal complex, nickel lapachol, are compared with those of the 2-nitroimidazole, misonidazole. These very different compounds were found to be surprisingly similar in terms of their reduction potential (-370 mV), enhancement ratios for killing of hypoxic Chinese hamster ovary cells by X-irradiation, and enhancement of DNA breaks in hypoxia. For nitroimidazoles, the sensitization depends on 'electron affinity', reduction of the nitro group; for nickel lapachol it is the metal which is necessary for reduction, yet the sensitization efficiencies are remarkably close. However, the metal complex has additional activities (some sensitization in aerobic cells; increased sensitization with preincubation) which are as yet unexplained but are assumed to be related to the nature of the naphthoquinone ligand, rather than to the reduction of the metal. (Author).

  10. Directed synthesis of a heterobimetallic complex based on a novel unsymmetric double-Schiff-base ligand: preparation, characterization, reactivity and structures of hetero- and homobimetallic nickel(II) and zinc(II) complexes.

    Science.gov (United States)

    Roth, Arne; Buchholz, Axel; Rudolph, Manfred; Schütze, Eileen; Kothe, Erika; Plass, Winfried

    2008-01-01

    A series of bimetallic zinc(II) and nickel(II) complexes based on the novel dinucleating unsymmetric double-Schiff-base ligand benzoic acid [1-(3-{[2-(bispyridin-2-ylmethylamino)ethylimino]methyl}-2-hydroxy-5-methylphenyl)methylidene]hydrazide (H(2)bpampbh) has been synthesized and structurally characterized. The metal centers reside in two entirely different binding pockets provided by the ligand H(2)bpampbh, a planar tridentate [ONO] and a pentadentate [ON(4)] compartment. The utilized ligand H(2)bpampbh has been synthesized by condensation of the single-Schiff-base proligand Hbpahmb with benzoic acid hydrazide. The reaction of H(2)bpampbh with two equivalents of either zinc(II) or nickel(II) acetate yields the homobimetallic complexes [Zn(2)(bpampbh)(mu,eta(1)-OAc)(eta(1)-OAc)] (ZnZn) and [Ni(2)(bpampbh)(mu-H(2)O)(eta(1)-OAc)(H(2)O)](OAc) (NiNi), respectively. Simultaneous presence of one equivalent zinc(II) and one equivalent nickel(II) acetate results in the directed formation of the heterobimetallic complex [NiZn(bpampbh)(mu,eta(1)-OAc)(eta(1)-OAc)] (NiZn) with a selective binding of the nickel ions in the pentadentate ligand compartment. In addition, two homobimetallic azide-bridged complexes [Ni(2)(bpampbh)(mu,eta(1)-N(3))]ClO(4) (NiNi(N(3))) and [Ni(2)(bpampbh)(mu,eta(1)-N(3))(MeOH)(2)](ClO(4))(0.5)(N(3))(0.5) (NiNi(N(3))(MeOH)(2)) were synthesized. In all complexes, the metal ions residing in the pentadentate compartment adopt a distorted octahedral coordination geometry, whereas the metal centers placed in the tridentate compartment vary in coordination number and geometry from square-planar (NiNi(N(3))) and square-pyramidal (ZnZn and NiZn), to octahedral (NiNi and NiNi(N(3))(MeOH)(2)). In the case of complex NiNi(N(3)) this leads to a mixed-spin homodinuclear nickel(II) complex. All compounds have been characterized by means of mass spectrometry as well as IR and UV/Vis spectroscopies. Magnetic susceptibility measurements show significant zero

  11. Recent Advances in Carbon Supported Metal Nanoparticles Preparation for Oxygen Reduction Reaction in Low Temperature Fuel Cells

    Directory of Open Access Journals (Sweden)

    Yaovi Holade

    2015-03-01

    Full Text Available The oxygen reduction reaction (ORR is the oldest studied and most challenging of the electrochemical reactions. Due to its sluggish kinetics, ORR became the major contemporary technological hurdle for electrochemists, as it hampers the commercialization of fuel cell (FC technologies. Downsizing the metal particles to nanoscale introduces unexpected fundamental modifications compared to the corresponding bulk state. To address these fundamental issues, various synthetic routes have been developed in order to provide more versatile carbon-supported low platinum catalysts. Consequently, the approach of using nanocatalysts may overcome the drawbacks encountered in massive materials for energy conversion. This review paper aims at summarizing the recent important advances in carbon-supported metal nanoparticles preparation from colloidal methods (microemulsion, polyol, impregnation, Bromide Anion Exchange… as cathode material in low temperature FCs. Special attention is devoted to the correlation of the structure of the nanoparticles and their catalytic properties. The influence of the synthesis method on the electrochemical properties of the resulting catalysts is also discussed. Emphasis on analyzing data from theoretical models to address the intrinsic and specific electrocatalytic properties, depending on the synthetic method, is incorporated throughout. The synthesis process-nanomaterials structure-catalytic activity relationships highlighted herein, provide ample new rational, convenient and straightforward strategies and guidelines toward more effective nanomaterials design for energy conversion.

  12. Preparation of Bimetallic Pd-Co Nanoparticles on Graphene Support for Use as Methanol Tolerant Oxygen Reduction Electrocatalysts

    Directory of Open Access Journals (Sweden)

    R. N. Singh

    2012-12-01

    Full Text Available Graphene-supported (40-x wt% Pd x wt% Co (0≤x≤13.33 alloys/composites have been prepared by a microwave-assisted polyol reduction method and been investigated for their structural and electrocatalytic properties for the oxygen reduction reaction (ORR in 0.5 M H2SO4 at 298 K. The study demonstrated that the bimetallic Pd-Co composite nanoparticles are, in fact, alloy nanoparticles with fcc crystalline structure. Partial substitution of Pd by Co (from 3.64 to 13.33 wt% in 40 wt% Pd/graphene decreases the lattice parameter as well as the crystallite size and increases the apparent catalytic activity, the latter, however, being the greatest with 8 wt% Co. The ORR activity of the active 32 wt% Pd 8wt% Co is found to be considerably low when it was deposited on the support multiwall carbon nanotubes under similar conditions. The rotating disk electrode study indicated that the ORR on 32 wt% Pd 8 wt% Co/GNS in 0.5 M H2SO4 follows approximately the four-electron pathway.

  13. Method of determining the extent to which a nickel structure has been attached by a fluorine-containing gas

    Science.gov (United States)

    Brusie, James P.

    2004-07-13

    The method of determining the extent to which a nickel structure has been attacked by a halogen containing gas to which it has been exposed which comprises preparing a quantity of water substantially free from dissolved oxygen, passing ammonia gas through a cuprammonium solution to produce ammonia substantially free from oxygen, dissolving said oxygen-free ammonia in said water to produce a saturated aqueous ammonia solution free from uncombined oxygen, treating at least a portion of said nickel structure of predetermined weight with said solution to dissolve nickel compounds from the surface of said structure without dissolving an appreciable amount of said nickel and analyzing the resulting solution to determine the quantity of said nickel compounds that was associated with said said portion of said structure to determine the proportion of combined nickel in said nickel structure.

  14. Method of Determining the Extent to which a Nickel Structure has been Attached by a Fluorine-Containing Gas

    Energy Technology Data Exchange (ETDEWEB)

    Brusie, James P.

    2004-07-13

    The method of determining the extent to which a nickel structure has been attacked by a halogen containing gas to which it has been exposed which comprises preparing a quantity of water substantially free from dissolved oxygen, passing ammonia gas through a cuprammonium solution to produce ammonia substantially free from oxygen, dissolving said oxygen-free ammonia in said water to produce a saturated aqueous ammonia solution free from uncombined oxygen, treating at least a portion of said nickel structure of predetermined weight with said solution to dissolve nickel compounds from the surface of said structure without dissolving an appreciable amount of said nickel and analyzing the resulting solution to determine the quantity of said nickel compounds that was associated with said said portion of said structure to determine the proportion of combined nickel in said nickel structure.

  15. The accumulation of nickel in human lungs.

    OpenAIRE

    Edelman, D A; Roggli, V L

    1989-01-01

    Using data from published studies, lung concentrations of nickel were compare for persons with and without occupational exposure to nickel. As expected, the concentrations were much higher for persons with occupational exposure. To estimate the effects of nickel-containing tobacco smoke and nickel in the ambient air on the amount of nickel accumulated in lungs over time, a model was derived that took into account various variables related to the deposition of nickel in lungs. The model predic...

  16. Mixed-Ligand Complexes Of Nickel (II) With 2-Acetylpyridine ...

    African Journals Online (AJOL)

    The preparation and spectral properties of five nickel (II) mixed-ligands complexes (Ni [2-Actsc.Y]CI2), derived from 2-acetylpyridinethiosermicarbazones and some nitrogen/sulphur monodentate ligands such as thiophene, ammonia, picoline, pyridine and aniline are described. The complexes have been characterized on ...

  17. short communication binding of nickel and zinc ions with activated ...

    African Journals Online (AJOL)

    a

    ABSTRACT. Activated carbon was prepared from sugar cane fibre by carbonizing at 500 oC for 30 minutes. ... Equilibrium sorption of nickel and zinc ions by the activated carbon was studied using a range of metal ion .... which means that limited sorption cycles will be required in the treatment of waste water containing the ...

  18. A nanostructural study of Raney-type nickel catalysts

    NARCIS (Netherlands)

    Devred, F.

    2004-01-01

    Raney-type nickel catalysts have been applied in commercial hydrogenation reactions for decades. They are relatively cheap and have proven to be very efficient in hydrogenation. The preparation process is relatively simple, but it appears that many parameters have an influence on the performance of

  19. Nickel Excretion in Urine after Oral Administration

    DEFF Research Database (Denmark)

    Menne, T.; Mikkelsen, H. I.; Solgaard, Per Bent

    1978-01-01

    In recent years the importance of internal exposure to nickel in patients with recurrent hand eczema and nickel allergy has become evident. The present study was performed in order to investigate the value of urinary nickel determinations as an index of oral nickel intake. After oral administration...... of 5.6 mg nickel (as the sulfate), increased nickel excretion was found over the following 2-3 days. We conclude that consecutive urinary nickel determinations are able to disclose variations in oral intake of nickel....

  20. Nickel release from nickel-plated metals and stainless steels.

    Science.gov (United States)

    Haudrechy, P; Foussereau, J; Mantout, B; Baroux, B

    1994-10-01

    Nickel release from nickel-plated metals often induces allergic contact dermatitis, but, for nickel-containing stainless steels, the effect is not well-known. In this paper, AISI 304, 316L, 303 and 430 type stainless steels, nickel and nickel-plated materials were investigated. 4 tests were performed: patch tests, leaching experiments, dimethylglyoxime (DMG) spot tests and electrochemical tests. Patch tests showed that 96% of the patients were intolerant to Ni-plated samples, and 14% to a high-sulfur stainless steel (303), while nickel-containing stainless steels with a low sulfur content elicited no reactions. Leaching experiments confirmed the patch tests: in acidic artificial sweat, Ni-plated samples released about 100 micrograms/cm2/week of nickel, while low-sulfur stainless steels released less than 0.03 microgram/cm2/week of nickel, and AISI 303 about 1.5 micrograms/cm2/week. Attention is drawn to the irrelevance of the DMG spot test, which reveals Ni present in the metal bulk but not its dissolution rate. Electrochemical experiments showed that 304 and 316 grades remain passive in the environments tested, while Ni-plated steels and AISI 303 can suffer significant cation dissolution. Thus, Ni-containing 304 and 316 steels should not induce contact dermatitis, while 303 should be avoided. A reliable nitric acid spot test is proposed to distinguish this grade from other stainless steels.

  1. Electrolytic Recovery of Nickel from Spent Electroless Nickel Bath Solution

    Directory of Open Access Journals (Sweden)

    R. Idhayachander

    2010-01-01

    Full Text Available Plating industry is one of the largest polluting small scale industries and nickel plating is among the important surface finishing process in this industry. The waste generated during this operation contains toxic nickel. Nickel removal and recovery is of great interest from spent bath for environmental and economic reasons. Spent electroless nickel solution from a reed relay switch manufacturing industry situated in Chennai was taken for electrolytic recovery of nickel. Electrolytic experiment was carried out with mild steel and gold coated mild steel as cathode and the different parameters such as current density, time, mixing and pH of the solution were varied and recovery and current efficiency was studied. It was noticed that there was an increase in current efficiency up to 5 A/dm2 and after that it declines. There is no significant improvement with mixing but with modified cathode there was some improvement. Removal of nickel from the spent electroless nickel bath was 81.81% at 5 A/dm2 and pH 4.23. Under this condition, the content of nickel was reduced to 0.94 g/L from 5.16 g/L. with 62.97% current efficiency.

  2. StreetWise: developing a serious game to support forensic mental health service users' preparation for discharge: a feasibility study.

    Science.gov (United States)

    Reynolds, L M; Davies, J P; Mann, B; Tulloch, S; Nidsjo, A; Hodge, P; Maiden, N; Simpson, A

    2017-05-01

    WHAT IS KNOWN ON THE SUBJECT?: Serious gaming can support learning and development. The use of serious games for skills development and the rehearsal of the management of events that cannot be replicated in real life is well established. Few serious games have been used in mental health services, and none in forensic mental health care. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: How a serious game may be coproduced by forensic mental health service users and game developers The acceptability of the therapeutic use of serious gaming by forensic mental health service users and providers. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Computer games may be used by practitioners in their therapeutic work with forensic mental health service users. Mental health nurses to use serious games to creatively and safely bridge the gap for service users between receiving care in controlled environments and living more independent in the community. Introduction Assessment of users' skills and confidence to safely respond to risky community-based situations underpins discharge planning. Serious games have been used for skills development, and this study trialled their use in forensic mental health services. Aim The aim was to develop and test the acceptability and usability of an innovative serious game to support forensic mental health service users' preparation for discharge. Method A prototype serious game was developed by service users and researchers. Acceptability and usability testing was undertaken and service providers interviewed about the acceptability of serious gaming for forensic mental health services. Result A prototype game was produced and successfully trialled by service users. However, both service users and providers identified that work needed to be done to develop and test a game with greater complexity. Discussion The acceptability and usability of using serious games to support service users to develop skills needed for successful discharge was demonstrated

  3. The Preparation and Characterization of Immobilized TiO2/PEG by Using DSAT as a Support Binder

    Directory of Open Access Journals (Sweden)

    Wan Izhan Nawawi

    2016-12-01

    Full Text Available Immobilized TiO2 was prepared by adding a small composition of polyethylene glycol (PEG as a binder, and this paper reported for the very first time the formation of C=O from oxidized PEG, which acted as an electron injector in enhancing photoactivity. Water-based TiO2 with PEG formulation was deposited by using a brush technique onto double-sided adhesive tape (DSAT as a support binder to increase the adhesiveness of immobilized TiO2. The photocatalytic activity of immobilized TiO2-PEG was measured by photodegradation of 12 mg·L−1 methylene blue (MB dye. The optimum condition of immobilized TiO2-PEG was observed at TiO2/PEG-2 (TP2 with 10:0.1 for the TiO2/PEG ratio, which resulted in a 1.8-times higher photodegradation rate as compared to the suspension mode of pristine TiO2. The high photodegradation rate was due to the formation of the active C=O bond from oxidized PEG binder in immobilized TiO2-PEG as observed by Fourier transform infrared and X-ray photoelectron spectroscopy analyses. The presence of C=O has escalated the photoactivity by forming an electron injector to a conduction band of TiO2 as proven by higher photoluminescence intensity obtained for TP2 as compared to pristine TiO2. The TP2 sample has also increased its adhesiveness when DSAT is applied as a support binder where it can be recycled up to eight times and comparable to recent photocatalysis cycle developments.

  4. Point defects in nickel

    International Nuclear Information System (INIS)

    Peretto, P.

    1969-01-01

    The defects in electron irradiated nickel (20 deg. K) or neutron irradiated nickel (28 deg. K) are studied by simultaneous analysis using the magnetic after-effect, electron microscopy and electrical resistivity recovery. We use zone refined nickel (99.999 per cent) which, for some experiments, is alloyed with a small amount of iron (for example 0.1 per cent Fe). The temperature dependant electrical recovery may be divided in four stages. The sub-stages I B (31 deg. K), I C (42 deg. K), I D (from to 57 deg. K) and I E (62 deg. K) of stage I are due to the disappearance of single interstitials into vacancies. The interstitial defect has a split configuration with a migration energy of about 0.15 eV. In the close pair which disappears in stage I B the interstitial is found to be in a 3. neighbour position whilst in stage I D it is near the direction from the vacancy. In stage I E there is no longer any interaction between the interstitial and the vacancy. The stage II is due to more complicated interstitial defects: di-interstitials for stage II B (84 deg. K) and larger and larger interstitial loops for the following sub-stages. The loops may be seen by electron microscopy. Impurities can play the role of nucleation centers for the loops. Stages III A (370 deg. K) and III B (376 deg. K) are due to two types of di-vacancies. During stage IV (410 deg. K) the single vacancies migrate. Vacancy type loops and interstitial type loops grow concurrently and disappear at about 800 deg. K as observed by electron microscopy. (author) [fr

  5. Nickel, cobalt, and their alloys

    CERN Document Server

    2000-01-01

    This book is a comprehensive guide to the compositions, properties, processing, performance, and applications of nickel, cobalt, and their alloys. It includes all of the essential information contained in the ASM Handbook series, as well as new or updated coverage in many areas in the nickel, cobalt, and related industries.

  6. Bimetallic nickel-cobalt nanosized layers supported on polar ZnO surfaces: metal-support interaction and alloy effects studied by synchrotron radiation X-ray photoelectron spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Law, Y.T.; Skála, T.; Pis, I.; Nehasil, V.; Vondráček, Martin; Zafeiratos, S.

    2012-01-01

    Roč. 116, č. 18 (2012), s. 10048-10056 ISSN 1932-7447 R&D Projects: GA MŠk(CZ) LC06058; GA ČR GD202/09/H041 Institutional support: RVO:68378271 Keywords : mc fuel-cell * hydrogen -production * oxide surfaces Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.814, year: 2012

  7. Fischer-Tropsch Performance of an SiO2-Supported Co-Based Catalyst Prepared by Hydrogen Dielectric-Barrier Discharge Plasma

    International Nuclear Information System (INIS)

    Fu Tingjun; Huang Chengdu; Lv Jing; Li Zhenhua

    2014-01-01

    A silica-supported cobalt catalyst was prepared by hydrogen dielectric-barrier discharge (H 2 -DBD) plasma. Compared to thermal hydrogen reduction, H 2 -DBD plasma treatment can not only fully decompose the cobalt precursor but also partially reduce the cobalt oxides at lower temperature and with less time. The effect of the discharge atmosphere on the property of the plasma-prepared catalyst and the Fischer-Tropsch synthesis activity was studied. The results indicate that H 2 -DBD plasma treatment is a promising alternative for preparing Co/SiO 2 catalysts from the viewpoint of energy savings and efficiency

  8. Self-Supporting, Hydrophobic, Ionic Liquid-Based Reference Electrodes Prepared by Polymerization-Induced Microphase Separation.

    Science.gov (United States)

    Chopade, Sujay A; Anderson, Evan L; Schmidt, Peter W; Lodge, Timothy P; Hillmyer, Marc A; Bühlmann, Philippe

    2017-10-27

    Interfaces of ionic liquids and aqueous solutions exhibit stable electrical potentials over a wide range of aqueous electrolyte concentrations. This makes ionic liquids suitable as bridge materials that separate in electroanalytical measurements the reference electrode from samples with low and/or unknown ionic strengths. However, methods for the preparation of ionic liquid-based reference electrodes have not been explored widely. We have designed a convenient and reliable synthesis of ionic liquid-based reference electrodes by polymerization-induced microphase separation. This technique allows for a facile, single-pot synthesis of ready-to-use reference electrodes that incorporate ion conducting nanochannels filled with either 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or 1-dodecyl-3-methylimidazolium bis(trifluoromethyl sulfonyl)imide as ionic liquid, supported by a mechanically robust cross-linked polystyrene phase. This synthesis procedure allows for the straightforward design of various reference electrode geometries. These reference electrodes exhibit a low resistance as well as good reference potential stability and reproducibility when immersed into aqueous solutions varying from deionized, purified water to 100 mM KCl, while requiring no correction for liquid junction potentials.

  9. Self-Supporting, Hydrophobic, Ionic Liquid-Based Reference Electrodes Prepared by Polymerization-Induced Microphase Separation

    Energy Technology Data Exchange (ETDEWEB)

    Chopade, Sujay A.; Anderson, Evan L.; Schmidt, Peter W.; Lodge, Timothy P.; Hillmyer, Marc A.; Bühlmann, Philippe (UMM)

    2017-09-25

    Interfaces of ionic liquids and aqueous solutions exhibit stable electrical potentials over a wide range of aqueous electrolyte concentrations. This makes ionic liquids suitable as bridge materials that separate in electroanalytical measurements the reference electrode from samples with low and/or unknown ionic strengths. However, methods for the preparation of ionic liquid-based reference electrodes have not been explored widely. We have designed a convenient and reliable synthesis of ionic liquid-based reference electrodes by polymerization-induced microphase separation. This technique allows for a facile, single-pot synthesis of ready-to-use reference electrodes that incorporate ion conducting nanochannels filled with either 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or 1-dodecyl-3-methylimidazolium bis(trifluoromethyl sulfonyl)imide as ionic liquid, supported by a mechanically robust cross-linked polystyrene phase. This synthesis procedure allows for the straightforward design of various reference electrode geometries. These reference electrodes exhibit a low resistance as well as good reference potential stability and reproducibility when immersed into aqueous solutions varying from deionized, purified water to 100 mM KCl, while requiring no correction for liquid junction potentials.

  10. Preparation of reusable bioreactors using reversible immobilization of enzyme on monolithic porous polymer support with attached gold nanoparticles.

    Science.gov (United States)

    Lv, Yongqin; Lin, Zhixing; Tan, Tianwei; Svec, Frantisek

    2014-01-01

    Porcine lipase has been reversibly immobilized on a monolithic polymer support containing thiol functionalities prepared within confines of a fused silica capillary and functionalized with gold nanoparticles. Use of gold nanoparticles enabled rejuvenation of the activity of the deactivated reactor simply by stripping the inactive enzyme from the nanoparticles using 2-mercaptoethanol and subsequent immobilization of fresh lipase. This flow through enzymatic reactor was then used to catalyze the hydrolysis of glyceryl tributyrate (tributyrin). The highest activity was found within a temperature range of 37-40°C. The reaction kinetics is characterized by Michaelis-Menten constant, Km  = 10.9 mmol/L, and maximum reaction rate, Vmax  = 5.0 mmol/L min. The maximum reaction rate for the immobilized enzyme is 1,000 times faster compared to lipase in solution. The fast reaction rate enabled to achieve 86.7% conversion of tributyrin in mere 2.5 min and an almost complete conversion in 10 min. The reactor lost only less than 10% of its activity even after continuous pumping through it a solution of substrate equaling 1,760 reactor volumes. Finally, potential application of this enzymatic reactor was demonstrated with the transesterification of triacylglycerides from kitchen oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel. © 2013 Wiley Periodicals, Inc.

  11. Zinc-nickel alloy electrodeposits for water electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Sheela, G.; Pushpavanam, Malathy; Pushpavanam, S. [Central Electrochemical Research Inst., Karaikudi (India)

    2002-06-01

    Electrodeposited zinc-nickel alloys of various compositions were prepared. A suitable electrolyte and conditions to produce alloys of various compositions were identified. Alloys produced on electroformed nickel foils were etched in caustic to leach out zinc and to produce the Raney type, porous electro catalytic surface for hydrogen evolution. The electrodes were examined by polarisation measurements, to evaluate their Tafel parameters, cyclic voltammetry, to test the change in surface properties on repeated cycling, scanning electron microscopy to identify their microstructure and X-ray diffraction. The catalytic activity as well as the life of the electrode produced from 50% zinc alloy was found to be better than others. (Author)

  12. Nanoparticles of nickel hexacyanoferrate; Nanoparticulas de hexacianoferrato de niquel

    Energy Technology Data Exchange (ETDEWEB)

    Bicalho, U.O.; Santos, D.C.; Silvestrini, D.R.; Trama, B.; Carmo, D.R. do, E-mail: docarmo@dfq.feis.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Faculdade de Engenharia

    2014-07-01

    Nanoparticles of nickel hexacyanoferrate (NHNi) were prepared in three medium (aqueous, formamide and aqueous/formamide). The materials were characterized by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), electronica spectroscopy in the ultraviolet-visible (UV-Vis) region and also by cyclic voltammetry (CV). By spectroscopic analysis of X-ray diffraction was possible to estimate the size of the particles obtained by the Scherrer equation. The graphite paste electrodes containing nanoparticles of nickel hexacyanoferrate means formamide was sensitive to different concentrations of Dipyrone. (author)

  13. Characterization of nickel nanocones routed by electrodeposition without any template.

    Science.gov (United States)

    Hang, Tao; Li, Ming; Fei, Qin; Mao, Dali

    2008-01-23

    This work reports the synthesis of Ni nanocones by a one-step electrodeposition method without any template. With the addition of ethylenediamine dihydrochloride (EDA·2HCl) in the nickel plating solution, the novel Ni conical structure can be easily deposited onto different metal surfaces. The as-prepared nickel nanocones grow preferentially along [Formula: see text] directions with very sharp tips. The conical structures are single crystalline without any disruption of the lattice planes. In addition, the Ni nanocone structure is demonstrated to show magnetocrystalline anisotropy and enhance the magnetic properties when compared with other Ni nanostructures.

  14. Characterization and assessment of dermal and inhalable nickel exposures in nickel production and primary user industries.

    Science.gov (United States)

    Hughson, G W; Galea, K S; Heim, K E

    2010-01-01

    The aim of this study was to measure the levels of nickel in the skin contaminant layer of workers involved in specific processes and tasks within the primary nickel production and primary nickel user industries. Dermal exposure samples were collected using moist wipes to recover surface contamination from defined areas of skin. These were analysed for soluble and insoluble nickel species. Personal samples of inhalable dust were also collected to determine the corresponding inhalable nickel exposures. The air samples were analysed for total inhalable dust and then for soluble, sulfidic, metallic, and oxidic nickel species. The workplace surveys were carried out in five different workplaces, including three nickel refineries, a stainless steel plant, and a powder metallurgy plant, all of which were located in Europe. Nickel refinery workers involved with electrolytic nickel recovery processes had soluble dermal nickel exposure of 0.34 microg cm(-2) [geometric mean (GM)] to the hands and forearms. The GM of soluble dermal nickel exposure for workers involved in packing nickel salts (nickel chloride hexahydrate, nickel sulphate hexahydrate, and nickel hydroxycarbonate) was 0.61 microg cm(-2). Refinery workers involved in packing nickel metal powders and end-user powder operatives in magnet production had the highest dermal exposure (GM = 2.59 microg cm(-2) soluble nickel). The hands, forearms, face, and neck of these workers all received greater dermal nickel exposure compared with the other jobs included in this study. The soluble nickel dermal exposures for stainless steel production workers were at or slightly above the limit of detection (0.02 microg cm(-2) soluble nickel). The highest inhalable nickel concentrations were observed for the workers involved in nickel powder packing (GM = 0.77 mg m(-3)), although the soluble component comprised only 2% of the total nickel content. The highest airborne soluble nickel exposures were associated with refineries using

  15. Substitution effects of a carbonated hydroxyapatite biomaterial against intoxication chloride nickel-exposed rats.

    Science.gov (United States)

    Boulila, Salha; Elfeki, Abdelfattah; Oudadesse, Hassane; Elfeki, Hafed

    2015-03-01

    This study aimed to investigate the potential effects of a synthetic apatite (carbonated hydroxyapatite) on the detoxification of a group of male "Wistar" rats exposed to nickel chloride. Toxicity was evaluated by rats' bioassay of nickel chloride. Wistar rats received this metal daily by gavage for seven days (4 mg/ml nickel chloride/200 g body weight, BW). To detoxify this organism, a subcutaneous implantation of the apatite is made. The results revealed that exposure to nickel induced oxidative stress, disorders in the balances of ferric phosphocalcic, renal failures, liver toxicity and significant increase in nickel rates in the bones of intoxicated rats. The application of the carbonated hydroxyapatite presented in this study restored those disorders back to normal. The synthetic apatite protected the rats against the toxic effects of nickel by lowering the levels of lipid peroxidation markers and improving the activities of defense enzymes. It also amended ferric and phosphocalcic equilibriums, protected liver and kidney functions and reduced the nickel rate in the bones of the rats. Overall, the results provided strong support for the protective role of carbonated hydroxyapatite in the detoxification of rats exposed to nickel. Those beneficial effects were further confirmed by physico-chemical characterization (X-ray diffraction and infrared spectroscopy), which revealed its property of anionic and cationic substitution, thus supporting its promising candidacy for future biomedical application. The hydroxyapatite is an effective biomaterial to solve health problems, particularly detoxification against metals (nickel).

  16. Gasification of Nickel-Preloaded Oil Palm Biomass with Air

    Directory of Open Access Journals (Sweden)

    Syed Shatir A. Syed-Hassan

    2016-10-01

    Full Text Available This study experimentally investigates the gasification of nickel-preloaded oil palm biomass as an alternative catalytic approach to produce clean syngas. To eliminate the use of catalyst support, nickel was added directly to the oil palm mesocarp fiber via ion-exchange using an aqueous solution of nickel nitrate. Nickel species was found to disperse very well on the biomass at a nano-scale dispersion. The presence of the finely dispersed nickels on biomass enhanced syngas production and reduced tar content in the producer gas during the air gasification of biomass. It is believed that nickel particles attached on the biomass and its char promote the catalytic cracking of tar on their surface and supply free radicals to the gas phase to enhance the radical-driven gas-phase reactions for the reforming of high molecular weight hydrocarbons. The unconsumed nickel-containing char shows great potential to be re-utilised as a catalyst to further enhance the destruction of tar components in the secondary tar reduction process. Copyright © 2016 BCREC GROUP. All rights reserved Received: 12nd September 2015; Revised: 10th January 2016; Accepted:16th January 2016 How to Cite: Syed-Hassan, S.S.A., Nor-Azemi, S. (2016. Gasification of Nickel-Preloaded Oil Palm Biomass with Air. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (3: 262-272 (doi:10.9767/bcrec.11.3.566.262-272 Permalink/DOI: http://doi.org/10.9767/bcrec.11.3.566.262-272

  17. Nickel Oxide and Nickel Co-doped Graphitic Carbon Nitride Nanocomposites and its Octylphenol Sensing Application

    KAUST Repository

    Gong, Wanyun

    2015-11-16

    Nickel oxide and nickel co-doped graphitic carbon nitride (NiO-Ni-GCN) nanocomposites were successfully prepared by thermal treatment of melamine and NiCl2 6H2O. NiO-Ni-GCN nanocomposites showed superior electrochemical catalytic activity for the oxidation of octylphenol to pure GCN. A detection method of octylphenol in environmental water samples was developed based at NiO-Ni-GCN nanocomposites modified electrode under infrared light irradiation. Differential pulse voltammetry was used as the analytic technique of octylphenol, exhibiting stable and specific concentration-dependent oxidation signal in the presence of octylphenol in the range of 10nM to 1μM and 1μM to 50μM, with a detection limit of 3.3nM (3S/N). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Nb effect in the nickel oxide-catalyzed low-temperature oxidative dehydrogenation of ethane

    KAUST Repository

    Zhu, Haibo

    2012-01-01

    A method for the preparation of NiO and Nb-NiO nanocomposites is developed, based on the slow oxidation of a nickel-rich Nb-Ni gel obtained in citric acid. The resulting materials have higher surface areas than those obtained by the classical evaporation method from nickel nitrate and ammonium niobium oxalate. These consist in NiO nanocrystallites (7-13 nm) associated, at Nb contents >3 at.%., with an amorphous thin layer (1-2 nm) of a niobium-rich mixed oxide with a structure similar to that of NiNb 2O 6. Unlike bulk nickel oxides, the activity of these nanooxides for low-temperature ethane oxidative dehydrogenation (ODH) has been related to their redox properties. In addition to limiting the size of NiO crystallites, the presence of the Nb-rich phase also inhibits NiO reducibility. At Nb content >5 at.%, Nb-NiO composites are thus less active for ethane ODH but more selective, indicating that the Nb-rich phase probably covers part of the unselective, non-stoichiometric, active oxygen species of NiO. This geometric effect is supported by high-resolution transmission electron microscopy observations. The close interaction between NiO and the thin Nb-rich mixed oxide layer, combined with possible restructuration of the nanocomposite under ODH conditions, leads to significant catalyst deactivation at high Nb loadings. Hence, the most efficient ODH catalysts obtained by this method are those containing 3-4 at.% Nb, which combine high activity, selectivity, and stability. The impact of the preparation method on the structural and catalytic properties of Nb-NiO nanocomposites suggests that further improvement in NiO-catalyzed ethane ODH can be expected upon optimization of the catalyst. © 2011 Elsevier Inc. All rights reserved.

  19. Support acidity influence in NiMoS (Nickel and Molybdenum) catalyst for Marlim diesel; Influencia da acidez do suport de catalisadores NiMoS (Niquel e Molibidenio) no hidrotratamento de diesel Marlim

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, Sheila Guimaraes de Almeida; Zotin, Jose Luiz; Jesus, Anderson Gomes de; Santos, Bruno Martins; Medeiros, Marcus Vinicius Costa [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2008-07-01

    The specification of diesel points to the reduction of the sulfur content, of the final boiling point, of the density range and increase of the cetane number. These two last properties are directly related with the ability of the hydrotreating catalytic system in promoting the hydrogenation of aromatic structures and ring opening of the naphthenic compounds, which are both associated to low cetane number. In such way, more acidic catalysts, able to promote the cracking of naphthenic structures, should be evaluated for the diesel HDT. Three bifunctional NiMo catalysts with the same metal content, different acidity and similar active phase dispersion were prepared using alumina, silica-alumina and alumina-Y zeolite as supports. These catalysts were evaluated in a micro-reactor unit for diesel HDT aiming to correlate their activity with the support acidity. The alumina and alumina-zeolite supported catalysts presented better performance than the one supported on silica-alumina. NiMo/alumina-zeolite showed higher cetane and density improvement, associated with a slight decrease in the initial boiling point. (author)

  20. Preparation and study of IrO2/SiC–Si supported anode catalyst for high temperature PEM steam electrolysers

    DEFF Research Database (Denmark)

    Nikiforov, Aleksey; Tomás García, Antonio Luis; Petrushina, Irina

    2011-01-01

    A novel catalyst material for oxygen evolution electrodes was prepared and characterised by different techniques. IrO2 supported on a SiC–Si composite was synthesised by the Adams fusion method. XRD and nitrogen adsorption experiments showed an influence of the support on the surface properties...... of the IrO2 particles, affecting the IrO2 particle size. The prepared catalysts were electrochemically characterised by cyclic voltammetry experiments at 25,80,120 and 150 °C. In accordance with the observed variation in particle size, a support loading of up to 20% improved the activity of the catalyst....... Powder conductivity measurements were also performed, which showed the influence of the support particles in the packing of IrO2 particles, perhaps favouring the formation of channels and pores between particles, thus increasing the catalyst utilisation....

  1. Liquid phase methanol process development unit: installation, operation, and support studies. Topical report. Experimental catalyst preparation program

    Energy Technology Data Exchange (ETDEWEB)

    1984-01-01

    This report details the preparation of 29 catalyst samples under DOE contract No. DE-AC22-81PC30019. These were selected for gas phase activity testing from a total of 70 prepared. Based on activity results, three compositions were selected for further slurry phase testing in the Chem Systems, Inc. (CSI) laboratories. 11 references, 5 figures, 7 tables.

  2. The study of hydrogen electrosorption in layered nickel foam/palladium/carbon nanofibers composite electrodes

    International Nuclear Information System (INIS)

    Skowronski, J.M.; Czerwinski, A.; Rozmanowski, T.; Rogulski, Z.; Krawczyk, P.

    2007-01-01

    In the present work, the process of hydrogen electrosorption occurring in alkaline KOH solution on the nickel foam/palladium/carbon nanofibers (Ni/Pd/CNF) composite electrodes is examined. The layered Ni/Pd/CNF electrodes were prepared by a two-step method consisting of chemical deposition of a thin layer of palladium on the nickel foam support to form Ni/Pd electrode followed by coating the palladium layer with carbon nanofibers layer by means of the CVD method. The scanning electron microscope was used for studying the morphology of both the palladium and carbon layer. The process of hydrogen sorption/desorption into/from Ni/Pd as well as Ni/Pd/CNF electrode was examined using the cyclic voltammetry method. The amount of hydrogen stored in both types of composite electrodes was shown to increase on lowering the potential of hydrogen sorption. The mechanism of the anodic desorption of hydrogen changes depending on whether or not CNF layer is present on the Pd surface. The anodic peak corresponding to the removal of hydrogen from palladium is lower for Ni/Pd/CNF electrode as compared to that measured for Ni/Pd one due to a partial screening of the Pd surface area by CNF layer. The important feature of Ni/Pd/CNF electrode is anodic peak appearing on voltammetric curves at potential ca. 0.4 V more positive than the peak corresponding to hydrogen desorption from palladium. The obtained results showed that upon storing the hydrogen saturated Ni/Pd/CNF electrode at open circuit potential, diffusion of hydrogen from carbon to palladium phase occurs due to interaction between carbon fibers and Pd sites on the nickel foam support

  3. Application of 2-cyanoethyl n,n,n′,n′-tetraisopropylphosphorodiamidite for in situ preparation of deoxyribonucleoside phosphoramidites and their use in polymer-supported synthesis of oligodeoxyribonucleotides

    DEFF Research Database (Denmark)

    Nielsen, John; Taagaard, Michael; Marugg, John E.

    1986-01-01

    Deoxyribonucleoside phosphoramidites are prepared in situ from 5′-O,N-protected deoxyribonucleosides and 2-cyanoethyl N,N,N′,N′-tetraisopropylphosphorodiamidite with tetrazole as catalyst, and the solutions applied directly on an automatic solid-phase DNA synthesizer. Using LCAA-CPG support...

  4. Implementation of the Dutch Meeting Centres Support Program for people with dementia and their carers in Milan: process evaluation of the preparation phase.

    NARCIS (Netherlands)

    Westerman, Marjan J.; Farina, E.; van der Sanden, M.C.; Saibene, F.L.; Meiland, F.J.M.; Droes, R.M.; Chattat, R.

    2016-01-01

    Background & Aims: The Meeting Centres Support Programme (MCSP) for people with mild to moderately severe dementia and their carers proved effective in the Netherlands, and is now being implemented in other European countries. This study aimed to compare factors that at the preparation of two

  5. Mechanisms of nickel toxicity in microorganisms

    OpenAIRE

    Macomber, Lee; Hausinger, Robert P.

    2011-01-01

    Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological co...

  6. Effect of screw access hole preparation on fracture load of implant-supported zirconia-based crowns: an in vitro study

    Directory of Open Access Journals (Sweden)

    Hadi Mokhtarpour

    2016-07-01

    Full Text Available Background. Fracture load of implant-supported restorations is an important factor in clinical success. This study evaluated the effect of two techniques for screw access hole preparation on the fracture load of cement-screw-retained implant-supported zirconia-based crowns. Methods. Thirty similar cement-screw-retained implant-supported zirconia-based maxillary central incisor crowns were evaluated in three groups of 10. Group NH: with no screw access holes for the control; Group HBS: with screw access holes prepared with a machine before zirconia sintering; Group HAS: with screw access holes prepared manually after zirconia sintering. In group HBS, the access holes were virtually designed and prepared by a computer-assisted design/computer-assisted manufacturing system. In group HAS, the access holes were manually prepared after zirconia sintering using a diamond bur. The dimensions of the screw access holes were equal in both groups. The crowns were cemented onto same-size abutments and were then subjected to thermocycling. The fracture load values of the crowns were measured using a universal testing machine. Data were analyzed with ANOVA and Tukey test (P < 0.05. Results. The mean fracture load value for the group NH was 888.37 ± 228.92 N, which was the highest among the groups, with a significant difference (P < 0.0001. The fracture load values were 610.48 ± 125.02 N and 496.74 ± 104.10 Nin the HBS and HAS groups, respectively, with no significant differences (P = 0.44. Conclusion. Both techniques used for preparation of screw access holes in implant-supported zirconia-based crowns de-creased the fracture load.

  7. Removing nickel from nickel-coated carbon fibers

    Science.gov (United States)

    Hardianto, A.; Hertleer, C.; De Mey, G.; Van Langenhove, L.

    2017-10-01

    Conductive fibers/yarns are one of the most important materials for smart textiles because of their electrically conductive functionality combined with flexibility and light weight. They can be applied in many fields such as the medical sector, electronics, sensors and even as thermoelectric generators. Temperature sensors, for example, can be made using the thermocouple or thermopile principle which usually uses two different metal wires that can produce a temperature-dependent voltage. However, if metal wires are inserted into a textile structure, they will decrease the flexibility properties of the textile product. Nickel-coated Carbon Fiber (NiCF), a conductive textile yarn, has a potential use as a textile-based thermopile if we can create an alternating region of carbon and nickel along the fiber which in turn it can be used for substituting the metallic thermopile. The idea was to remove nickel from NiCF in order to obtain a yarn that contains alternating zones of carbon and nickel. Due to no literature reporting on how to remove nickel from NiCF, in this paper we investigated some chemicals to remove nickel from NiCF.

  8. Influence of dietary factors, age and nickel contact dermatitis on nickel excretion.

    Science.gov (United States)

    Darsow, Ulf; Fedorov, Michael; Schwegler, Ursula; Twardella, Dorothee; Schaller, Karl-Heinz; Habernegg, Renate; Fromme, Hermann; Ring, Johannes; Behrendt, Heidrun

    2012-12-01

    Nickel is a frequently detected cause of allergic contact dermatitis. Ingestion of nickel may lead to flares of nickel contact dermatitis. We examined nickel excretion in the urine of 164 female patients with and without nickel contact dermatitis. The associations between age, atopic dermatitis, nickel contact dermatitis and nickel exposure through nutrition (e.g. dietary supplements) and by patch tests were investigated prospectively. Nickel was measured with atomic absorption spectrometry with two different standardized methods. A nickel detection limit of 0.2 µg/l was exceeded by all samples. The 95th percentiles of urine nickel concentration were 3.77 µg/l (age 18-30 years) and 3.98 µg/l (age 31-46 years). Bivariate analyses pointed to significantly increased nickel excretion with increasing age, ingestion of dietary supplements, drinking of stagnant tap water, and consumption of nickel-rich food. In the multivariate analysis, age and dietary supplements remained significant predictors of high nickel excretion. A non-significant increase in the median concentration of nickel was observed after the administration of conventional nickel patch tests. Patients with atopic eczema showed urine nickel concentrations similar to those in non-atopic controls. The 95th percentile of nickel excretion in our study population markedly exceeded the actual reference value of 3 µg/l. Age and consumption of dietary supplements are the most important predictors. The use of stagnant tap water and consumption of nickel-rich food contribute to the total load. These factors should be explicitly mentioned when allergic patients on a low-nickel diet are counselled. In contrast, existing nickel contact sensitization was not more frequent in subjects with higher nickel excretion. Nickel patch testing may cause transient minor systemic nickel exposure. The findings of this study extend our understanding and management of factors associated with nickel allergy. © 2012 John Wiley

  9. Synthesis and Characterization of Nickel-Alumina Composites from Recycled Nickel Powder

    Directory of Open Access Journals (Sweden)

    V. G. Karayannis

    2012-01-01

    Full Text Available The recycling of metallic waste to create more valuable materials and their valorization into upgraded metal-based composites constitutes an important field of study. The composite industry nowadays considers environmental improvements as important as other properties of the materials. In the present paper, nickel powder was recycled from ferrous scrap, a low-cost and largely available material, by an effective hydrometallurgical recovery process. Then, this recycled powder was successfully used along with particulate α-alumina to prepare oblong nickel-based composite specimens with ceramic reinforcement loadings ranging from 0 to 30 wt.% by applying powder processing manufacturing techniques including cold isostatic pressing (CIP and sintering. The microstructures obtained were characterized, the specimens were subjected to three-point bend tests, and their fracture behaviour was evaluated. By increasing the % ceramic reinforcement content, density clearly decreases while strengthening is achieved, thus leading to development of lightweight and enhanced oblong nickel-alumina composites. The composite microstructure, and particularly the metal-ceramic interface bonding, has a strong impact on fracture behaviour upon external loading.

  10. Bio-preparates support the productivity of potato plants grown under desert farming conditions of north Sinai: Five years of field trials

    Directory of Open Access Journals (Sweden)

    Mohammed T. Abbas

    2014-01-01

    Full Text Available Organic agriculture as well as good agricultural practices (GAPs intrigues the concern of both consumers and producers of agricultural commodities. Bio-preparates of various rhizospheric microorganisms (RMOs are potential sources of biological inputs supporting plant nutrition and health. The response of open-field potatoes to the application of RMO bio-preparates, the biofertilizer “Biofertile” and the bioagent “Biocontrol”, were experimented over 5 successive years under N-hunger of north Sinai desert soils. Both vegetative and tuber yields of a number of tested cultivars were significantly improved due to rhizobacterial treatments. In the majority of cases, the biofertilizer “Biofertile” did successfully supply ca. 50% of plant N requirements, as the yield of full N-fertilized plants was comparable to those received 50% N simultaneously with bio-preparates treatment. The magnitude of inoculation was cultivar-dependent; cvs. Valor and Oceania were among the most responsive ones. Bio-preparate introduction to the plant–soil system was successful via soaking of tubers and/or spraying the plant canopy. The “Biocontrol” formulation was supportive in controlling plant pathogens and significantly increased the fruit yields. The cumulative effect of both bio-preparates resulted in tuber yield increases of ca. 25% over control.

  11. Excessive nickel release from mobile phones--a persistent cause of nickel allergy and dermatitis

    DEFF Research Database (Denmark)

    Jensen, Peter; Johansen, Jeanne D; Zachariae, Claus

    2011-01-01

    phones, we showed that eight (19.5%) of 41 mobile phones marketed in Denmark between 2003 and 2007 released nickel in concentrations that may result in nickel allergy and dermatitis. In 2009, the EU Nickel Directive was revised to include nickel-releasing mobile phones.......Despite the political intention to limit nickel allergy and dermatitis in Europeans, nickel allergy remains frequent. There are several explanations for the persistence of nickel allergy and dermatitis, including the increasing use of mobile phones. Before regulation of nickel release from mobile...

  12. Biosorption of nickel with barley straw.

    Science.gov (United States)

    Thevannan, Ayyasamy; Mungroo, Rubeena; Niu, Catherine Hui

    2010-03-01

    Wastewater containing nickel sulphate generated from a nickel plating industry is of great concern. In the present work, biosorption of nickel by barley straw from nickel sulphate solution was investigated. Nickel uptake at room temperature (23+/-0.5 degrees C) was very sensitive to solution pH, showing a better uptake value at a pH of 4.85+/-0.10 among the tested values. The nickel biosorption isotherm fitted well the Langmuir equation. When the ionic strength (IS) of the solution was increased from less than 0.02-0.6M, nickel uptake was reduced to 12% of that obtained at IS of less than 0.02 M. Barley straw showed a higher nickel uptake (0.61 mmol/g) than acid washed crab shells (0.04 mmol/g), demonstrating its potential as an adsorbent for removal of nickel. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  13. Photometric method for determination of nickel in hafnium-nickel-carbon alloy

    International Nuclear Information System (INIS)

    Ushakova, L.V.; Shishkina, Z.I.

    1978-01-01

    The photometric method based on the preparation of a red-coloured compound with dimethylglyoxime in ammoniacal solution in the presence of ammonium persulfate as an oxidizer Was used to determine Ni in hafnium base alloys. Hafnium hydrolysis is prevented by addition of tartaric acid. The accuracy of the method is confirmed by the analysis of imitating mixtures and also by comparing the results obtained with those of nickel Weight determination. Deviation between the results of two parallel determinations at the content of 0.2 and 10% of Ni does not exceed 0.05 and 0.5%, respectively, the duration of a determination run being 1 h

  14. EPIDEMIOLOGICAL AND PATHOGENETIC ASPECTS OF NICKEL POISONING

    Directory of Open Access Journals (Sweden)

    Vladmila Bojanic

    2007-04-01

    Full Text Available Nickel is widely distributed in the environment. High consumption of nickel containing products inevitably leads to environmental pollution by nickel and its derivatives at all stages of production, utilization, and disposal.Human exposure to nickel occurs primarily via inhalation and ingestion and is particularly high among nickel metallurgy workers. In addition, implantation of nickel-containing endoprostheses and iatrogenic administration of nickel-contaminated medica-tions leads to significant parenteral exposures. Exposure to nickel compounds can produce a variety of adverse effects on human health. Nickel allergy in the form of contact dermatitis is the most common reaction.A frontal headache, vertigo, nausea, vomiting, insomnia, and irritability are the most common signs of acute poisoning with nickel compounds. The respiratory tract, kidneys and liver suffer the most significant changes like nickel pneumoconiosis, chronic rhinitis and sinonasal tumors and transitory nephropathy. Although the accumulation of nickel in the body through chronic exposure can lead to lung fibrosis, cardiovascular and kidney diseases, the most serious concerns relate to nickel’s carcinogenic activity. Nickel compounds are carcinogenic to humans and metallic nickel is possibly carcinogenic to humans.

  15. Relationship between nickel allergy and diet

    Directory of Open Access Journals (Sweden)

    Sharma Ashimav

    2007-01-01

    Full Text Available Nickel is a ubiquitous trace element and it occurs in soil, water, air and of the biosphere. It is mostly used to manufacture stainless steel. Nickel is the commonest cause of metal allergy. Nickel allergy is a chronic and recurring skin problem; females are affected more commonly than males. Nickel allergy may develop at any age. Once developed, it tends to persist life-long. Nickel is present in most of the dietary items and food is considered to be a major source of nickel exposure for the general population. Nickel content in food may vary considerably from place to place due to the difference in nickel content of the soil. However, certain foods are routinely high in nickel content. Nickel in the diet of a nickel-sensitive person can provoke dermatitis. Careful selection of food with relatively low nickel concentration can bring a reduction in the total dietary intake of nickel per day. This can influence the outcome of the disease and can benefit the nickel sensitive patient.

  16. Relationship between nickel allergy and diet.

    Science.gov (United States)

    Sharma, Ashimav Deb

    2007-01-01

    Nickel is a ubiquitous trace element and it occurs in soil, water, air and of the biosphere. It is mostly used to manufacture stainless steel. Nickel is the commonest cause of metal allergy. Nickel allergy is a chronic and recurring skin problem; females are affected more commonly than males. Nickel allergy may develop at any age. Once developed, it tends to persist life-long. Nickel is present in most of the dietary items and food is considered to be a major source of nickel exposure for the general population. Nickel content in food may vary considerably from place to place due to the difference in nickel content of the soil. However, certain foods are routinely high in nickel content. Nickel in the diet of a nickel-sensitive person can provoke dermatitis. Careful selection of food with relatively low nickel concentration can bring a reduction in the total dietary intake of nickel per day. This can influence the outcome of the disease and can benefit the nickel sensitive patient.

  17. A Mechanistic Insight into the Nickel-Catalyzed Homocoupling Reaction of Terminal Alkynes

    OpenAIRE

    Ghosh, Subrata

    2018-01-01

    1,3-Diynes are frequently found as an important structural motif in natural products, pharmaceuticals and bioactive compounds, electronic and optical materials and supramolecular molecules. Copper and palladium complexes are widely used to prepare 1,3-diynes by homocoupling of terminal alkynes; albeit the potential of nickel complexes towards the same is essentially unexplored. Although a detailed study on the reported nickel-acetylene chemistry has not been carried out, a generalized mechani...

  18. Nickel-resistant bacteria from anthropogenically nickel-polluted and naturally nickel-percolated ecosystems.

    Science.gov (United States)

    Stoppel, R; Schlegel, H G

    1995-06-01

    DNA fragments harboring the nickel resistance determinants from bacteria isolated from anthropogenically polluted ecosystems in Europe and Zaire were compared with those harboring the nickel resistance determinants from bacteria isolated from naturally nickel-percolated soils from New Caledonia by DNA-DNA hybridization. The biotinylated DNA probes were derived from the previously described Alcaligenes eutrophus CH34, Alcaligenes xylosoxidans 31A, Alcaligenes denitrificans 4a-2, and Klebsiella oxytoca CCUG 15788 and four new nickel resistance-determining fragments cloned from strains isolated from soils under nickel-hyperaccumulating trees. Nine probes were hybridized with endonuclease-cleaved plasmid and total DNA samples from 56 nickel-resistant strains. Some of the New Caledonian strains were tentatively identified as Acinetobacter, Pseudomonas mendocina, Comamonas, Hafnia alvei, Burkholderia, Arthrobacter aurescens, and Arthrobacter ramosus strains. The DNA of most strains showed homologies to one or several of the following nickel resistance determinants: the cnr and ncc operons of the strains A. eutrophus CH34 and A. xylosoxidans 31A, respectively, the nre operon of strain 31A, and the nickel resistance determinants of K. oxytoca. On the basis of their hybridization reactions the nickel resistance determinants of the strains could be assigned to four groups: (i) cnr/ncc type, (ii) cnr/ncc/nre type, (iii) K. oxytoca type, and (iv) others. The majority of the strains were assigned to the known groups. Among the strains from Belgium and Zaire, exclusively the cnr/ncc and the cnr/ncc/nre types were found. Among the New Caledonian strains all four types were represented. Homologies to the nre operon were found only in combination with the cnr/ncc operon. The homologies to the cnr/ncc operon were the most abundant and were detected alone or together with homologies to the nre operon. Only the DNA of the strains isolated from soil in Scotland and the United States

  19. The EU Nickel Directive revisited--future steps towards better protection against nickel allergy

    DEFF Research Database (Denmark)

    Thyssen, Jacob P; Uter, Wolfgang; McFadden, John

    2011-01-01

    In July 2001, the EU Nickel Directive came into full force to protect European citizens against nickel allergy and dermatitis. Prior to this intervention, Northern European governments had already begun to regulate consumer nickel exposure. According to part 2 of the EU Nickel Directive and the D......In July 2001, the EU Nickel Directive came into full force to protect European citizens against nickel allergy and dermatitis. Prior to this intervention, Northern European governments had already begun to regulate consumer nickel exposure. According to part 2 of the EU Nickel Directive...... and the Danish nickel regulation, consumer items intended to be in direct and prolonged contact with the skin were not allowed to release more than 0.5 µg nickel/cm2/week. It was considered unlikely that nickel allergy would disappear altogether as a proportion of individuals reacted below the level defined...

  20. Relationship between nickel allergy and diet

    OpenAIRE

    Sharma Ashimav

    2007-01-01

    Nickel is a ubiquitous trace element and it occurs in soil, water, air and of the biosphere. It is mostly used to manufacture stainless steel. Nickel is the commonest cause of metal allergy. Nickel allergy is a chronic and recurring skin problem; females are affected more commonly than males. Nickel allergy may develop at any age. Once developed, it tends to persist life-long. Nickel is present in most of the dietary items and food is considered to be a major source of nickel exposure for the...

  1. Pulse reversal plating of nickel alloys

    DEFF Research Database (Denmark)

    Tang, Peter Torben

    2007-01-01

    Pulse plating has previously been reported to improve the properties of nickel and nickel alloy deposits. Typically, focus has been on properties such as grain size, hardness and smoothness. When pulse plating is to be utilised for microtechnologies such as microelectromechanical systems (MEMS......), internal stress and material distribution are even more important. With baths based upon nickel chloride, and nickel and cobalt chlorides, pulse reversal plating of both pure nickel and nickel-cobalt alloys has been used to fabricate tools for microinjection moulding. Pulse reversal plating of ternary soft...... magnetic alloys, comprising 45-65%Co, 15-35%Fe and 15-35%Ni, is also reported....

  2. Dry Reforming of Methane Using a Nickel Membrane Reactor

    Directory of Open Access Journals (Sweden)

    Jonas M. Leimert

    2017-12-01

    Full Text Available Dry reforming is a very interesting process for synthesis gas generation from CH 4 and CO 2 but suffers from low hydrogen yields due to the reverse water–gas shift reaction (WGS. For this reason, membranes are often used for hydrogen separation, which in turn leads to coke formation at the process temperatures suitable for the membranes. To avoid these problems, this work shows the possibility of using nickel self-supported membranes for hydrogen separation at a temperature of 800 ∘ C. The higher temperature effectively suppresses coke formation. The paper features the analysis of the dry reforming reaction in a nickel membrane reactor without additional catalyst. The measurement campaign targeted coke formation and conversion of the methane feedstock. The nickel approximately 50% without hydrogen separation. The hydrogen removal led to an increase in methane conversion to 60–90%.

  3. Ultrasmall Dispersible Crystalline Nickel Oxide Nanoparticles as High-Performance Catalysts for Electrochemical Water Splitting

    Czech Academy of Sciences Publication Activity Database

    Fominykh, K.; Feckl, J. M.; Sicklinger, J.; Döblinger, M.; Böcklein, S.; Ziegler, J.; Peter, L.; Rathouský, Jiří; Scheidt, E.-W.; Bein, T.; Fattakhova-Rohlfing, D.

    2014-01-01

    Roč. 24, č. 21 (2014), s. 3123-3129 ISSN 1616-301X Institutional support: RVO:61388955 Keywords : electrocatalysis * nickel oxide * nanocrystals Subject RIV: CG - Electrochemistry Impact factor: 11.805, year: 2014

  4. Synthesis, spectral (IR, UV-Vis and variable temperature NMR) characterization and crystal structure of (N-benzyl-N-furfuryldithicarbamato-S,S‧)(thiocyanato-N)(triphenylphosphine)nickel(II)

    Science.gov (United States)

    Valarmathi, P.; Thirumaran, S.; Sarmal, Lovely; Kant, Rajni

    2014-08-01

    Planar (N-benzyl-N-furfuryldithiocarbamato-S,S‧)(thiocyanato-N)(triphenylphospine)nickel(II), [Ni(bfdtc)(NCS)(PPh3)], (1) was prepared from bis(N-benzyl-N-furfuryldithiocarbamato-S,S‧)nickel(II), [Ni(bfdtc)2], (2) and characterized by elemental analysis, cyclic voltammetry, electronic, IR and variable temperature 1H and 13C NMR spectra. For complex 1, the thioureide vCsbnd N value is shifted to higher wavenumber compared to 2 and N13CS2 carbon signal observed for 1 is additionally shielded compared to the parent complex 2, suggesting increased strength of the thioureide bond due to the presence of the π-accepting phosphine. In the room temperature 13C NMR spectrum of 1, two pseudo doublets are observed in the aliphatic region. Variable temperature 13C NMR spectral studies suggest that the fast thiocyanate exchange appears to be responsible for the appearance of pseudo doublets. Single crystal X-ray structural analysis of 1 and 2 confirm the presence of four coordinated nickel in a distorted square planar arrangement with the NiS2PN and NiS4 chromophores, respectively. The Nisbnd S bonds are symmetric in 2 (2.1914(14) and 2.2073(13) Å). But significant asymmetry in Nisbnd S bond distances was observed in 1 (2.2202(8) Å and 2.1841 Å). This observation clearly supports the less effective trans effect of SCN- over PPh3. Cyclic voltammetric studies revealed easier reduction of nickel(II) to nickel(I) in complex 1 compared to 2.

  5. Influence of the processing parameters of slurries for the deposit of nickelate thick films

    International Nuclear Information System (INIS)

    Castillo, S.; Cienfuegos, R.F.; Fontaine, M.L.; Lenormand, P.; Bacchin, P.; Ansart, F.

    2007-01-01

    Thick films cathodes for Solid Oxide Fuel Cells (SOFC) are prepared by dip-coating slurries made of several lanthanum nickelate oxide powders onto yttria stabilized zirconia (YSZ) substrates. The processing parameters for the slurries preparation and the multilayers coating have been optimized to obtain homogeneous, crack-free, thick and adherent films after heat treatment

  6. Selective coating for solar panels. [using black chrome and black nickel

    Science.gov (United States)

    Mcdonald, G. E. (Inventor)

    1977-01-01

    The energy absorbing properties of solar heating panels are improved by depositing a black chrome coating of controlled thickness on a specially prepared surface of a metal substrate. The surface is prepared by depositing a dull nickel on the substrate, and the black chrome is plated on this low emittance surface to a thickness between 0.5 micron and 2.5 microns.

  7. Supporting and Preparing Future First-Generation College Students in the High School Environment: Implications for School Counselors

    Science.gov (United States)

    Bryant, Jill K.; Nicolas, Joanna

    2011-01-01

    This study surveyed college freshmen from two different institutions in order to examine differences between First-Generation College Students and Continuing-Generation College Students. Differences between groups emerged for high school academic preparation, college exploration behaviors, college application behaviors, and college decision-making…

  8. Mechanisms of nickel toxicity in microorganisms

    Science.gov (United States)

    Macomber, Lee

    2014-01-01

    Summary Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological concern. To date, the mechanisms of nickel toxicity in microorganisms and higher eukaryotes are poorly understood. In this review, we summarize nickel homeostasis processes used by microorganisms and highlight in vivo and in vitro effects of exposure to elevated concentrations of nickel. On the basis of this evidence we propose four mechanisms of nickel toxicity: 1) nickel replaces the essential metal of metalloproteins, 2) nickel binds to catalytic residues of non-metalloenzymes; 3) nickel binds outside the catalytic site of an enzyme to inhibit allosterically, and 4) nickel indirectly causes oxidative stress. PMID:21799955

  9. Adsorption isotherms for cesium ions in seawater of insoluble cobalt and nickel ferrocyanide-impregnated fibers

    International Nuclear Information System (INIS)

    Amakai, Wataru; Sugiyama, Mai; Fujiwara, Kunio; Umeno, Daisuke; Saito, Kyoichi; Sugo, Takanobu

    2014-01-01

    Cobalt or nickel ferrocyanide was impregnated into an anion-exchange polymer chain grafted onto a commercially available 6-nylon fiber. First, ferrocyanide ions (Fe(CN) 6 4- ) were bound to the anion-exchange fiber. Second, the fiber was made to reach with cobalt or nickel ions to form insoluble cobalt or nickel ferrocyanide via precipitation. For comparison, a commercially available anion-exchange bead was used as a support for the impregnation of insoluble cobalt or nickel ferrocyanide. The contents of metal ferrocyanides impregnated onto the fiber were approximately half those impregnated onto the bead. Adsorption isotherms of insoluble cobalt or nickel ferro-cyanide-impregnated fiber and bead for cesium ions in seawater correlated well with a Langmuir-type isotherm. The saturation capacity for cesium ions in seawater per gram of insoluble metal ferrocyanides was almost identical between the fiber and the bead. (author)

  10. Synthesis and Reactivity of New Aminophenolate Complexes of Nickel

    Directory of Open Access Journals (Sweden)

    Siqi Yu

    2014-09-01

    Full Text Available New well-defined, paramagnetic nickel complexes have been prepared and characterized by X-ray crystallography. The complexes were found to be active for the cross-coupling of alkyl electrophiles (especially ethyl 2-bromobutyrate with alkyl Grignard reagents. The ligand architecture in these new complexes could potentially be rendered chiral, opening up future possibilities for performing asymmetric cross-coupling reactions.

  11. Raman scattering in nanosized nickel oxide NiO

    International Nuclear Information System (INIS)

    Mironova-Ulmane, N; Kuzmin, A; Steins, I; Grabis, J; Sildos, I; Paers, M

    2007-01-01

    Magnetic ordering in nanosized (100 and 1500 nm) nickel oxide NiO powders, prepared by the plasma synthesis method, was studied using Raman scattering spectroscopy in a wide range of temperatures from 10 to 300 K. It was observed that the intensity of two-magnon band decreases rapidly for smaller crystallites size. This effect is attributed to a decrease of antiferromagnetic spin correlations and leads to the antiferromagnetic-to-paramagnetic phase transition

  12. Catalytic CO Oxidation over Au Nanoparticles Loaded Nanoporous Nickel Phosphate Composite

    Directory of Open Access Journals (Sweden)

    Xiaonan Leng

    2015-01-01

    Full Text Available Au/nickel phosphate-5 (Au/VSB-5 composite with the noble metal loading amount of 1.43 wt.% is prepared by using microporous VSB-5 nanocrystals as the support. Carbon monoxide (CO oxidation reaction is carried out over the sample with several catalytic cycles. Complete conversion of CO is achieved at 238°C over the catalyst at the first catalytic cycle. The catalytic activity improved greatly at the second cycle with the complete conversion fulfilled at 198°C and preserved for the other cycles. A series of experiments such as X-ray diffraction (XRD, high resolution transmission electron microscopy (HRTEM, ultraviolet-visible (UV-vis spectroscopy, and X-ray photoelectron spectroscopy (XPS are carried out to characterize the catalysts before and after the reaction to study the factors influencing this promotion at the second cycle.

  13. Ni-SiO2 Catalysts for the Carbon Dioxide Reforming of Methane: Varying Support Properties by Flame Spray Pyrolysis

    Directory of Open Access Journals (Sweden)

    Emma C. Lovell

    2015-03-01

    Full Text Available Silica particles were prepared by flame spray pyrolysis (FSP as a support for nickel catalysts. The impact of precursor feed rate (3, 5 and 7 mL/min during FSP on the silica characteristics and the ensuing effect on catalytic performance for the carbon dioxide, or dry, reforming of methane (DRM was probed. Increasing the precursor feed rate: (i progressively lowered the silica surface area from ≈340 m2/g to ≈240 m2/g; (ii altered the silanol groups on the silica surface; and (iii introduced residual carbon-based surface species to the sample at the highest feed rate. The variations in silica properties altered the (5 wt % nickel deposit characteristics which in turn impacted on the DRM reaction. As the silica surface area increased, the nickel dispersion increased which improved catalyst performance. The residual carbon-based species also appeared to improve nickel dispersion, and in turn catalyst activity, although not to the same extent as the change in silica surface area. The findings illustrate both the importance of silica support characteristics on the catalytic performance of nickel for the DRM reaction and the capacity for using FSP to control these characteristics.

  14. AN ELECTROPLATING METHOD OF FORMING PLATINGS OF NICKEL, COBALT, NICKEL ALLOYS OR COBALT ALLOYS

    DEFF Research Database (Denmark)

    1997-01-01

    An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys with reduced stresses in an electrodepositing bath of the type: Watt's bath, chloride bath or a combination thereof, by employing pulse plating with periodic reverse pulse and a sulfonated naphthalene...... additive. This method makes it possible to deposit nickel, cobalt, nickel or cobalt platings without internal stresses....

  15. Excessive nickel release from mobile phones--a persistent cause of nickel allergy and dermatitis

    DEFF Research Database (Denmark)

    Jensen, Peter; Johansen, Jeanne D; Zachariae, Claus

    2011-01-01

    Despite the political intention to limit nickel allergy and dermatitis in Europeans, nickel allergy remains frequent. There are several explanations for the persistence of nickel allergy and dermatitis, including the increasing use of mobile phones. Before regulation of nickel release from mobile...

  16. Synergetic Effect of Ultrasound, the Heterogeneous Fenton Reaction and Photocatalysis by TiO2 Loaded on Nickel Foam on the Degradation of Pollutants

    Science.gov (United States)

    Qiu, Shan; Xu, Shanwen; Li, Guangming; Yang, Jixian

    2016-01-01

    The synergistic effect of ultrasound, the heterogeneous Fenton reaction and photocatalysis was studied using a nickel foam (NF)-supporting TiO2 system and rhodamine B (RhB) as a target. The NF-supporting TiO2 system was prepared by depositing TiO2 on the skeleton of NF repeatedly and then calcining it. To optimize the conditions and parameters, the catalytic activity was tested in four systems (ultrasound alone (US), nickel foam (NF), US/NF and NF/US/H2O2). The optimal conditions were fixed at 0.1 g/mL NF, initial 5.00 mg/L RhB, 300 W ultrasonic power, pH = 3 and 5.00 mg/L H2O2. The effects of the dissolution of nickel from NF and quenching of the Fenton reaction were studied on degradation efficiency. When the heterogeneous Fenton reaction is combined with TiO2-photocatalysis, the pollutant removal efficiency is enhanced significantly. Through this synergistic effect, 22% and 80% acetochlor was degraded within 10 min and 80 min, respectively. PMID:28773580

  17. Synergetic Effect of Ultrasound, the Heterogeneous Fenton Reaction and Photocatalysis by TiO₂ Loaded on Nickel Foam on the Degradation of Pollutants.

    Science.gov (United States)

    Qiu, Shan; Xu, Shanwen; Li, Guangming; Yang, Jixian

    2016-06-08

    The synergistic effect of ultrasound, the heterogeneous Fenton reaction and photocatalysis was studied using a nickel foam (NF)-supporting TiO₂ system and rhodamine B (RhB) as a target. The NF-supporting TiO₂ system was prepared by depositing TiO₂ on the skeleton of NF repeatedly and then calcining it. To optimize the conditions and parameters, the catalytic activity was tested in four systems (ultrasound alone (US), nickel foam (NF), US/NF and NF/US/H₂O₂). The optimal conditions were fixed at 0.1 g/mL NF, initial 5.00 mg/L RhB, 300 W ultrasonic power, pH = 3 and 5.00 mg/L H₂O₂. The effects of the dissolution of nickel from NF and quenching of the Fenton reaction were studied on degradation efficiency. When the heterogeneous Fenton reaction is combined with TiO₂-photocatalysis, the pollutant removal efficiency is enhanced significantly. Through this synergistic effect, 22% and 80% acetochlor was degraded within 10 min and 80 min, respectively.

  18. Nickel exposure and plasma levels of biomarkers for assessing oxidative stress in nickel electroplating workers.

    Science.gov (United States)

    Tsao, Yu-Chung; Gu, Po-Wen; Liu, Su-Hsun; Tzeng, I-Shiang; Chen, Jau-Yuan; Luo, Jiin-Chyuan John

    2017-07-01

    The mechanism of nickel-induced pathogenesis remains elusive. To examine effects of nickel exposure on plasma oxidative and anti-oxidative biomarkers. Biomarker data were collected from 154 workers with various levels of nickel exposure and from 73 controls. Correlations between nickel exposure and oxidative and anti-oxidative biomarkers were determined using linear regression models. Workers with a exposure to high nickel levels had significantly lower levels of anti-oxidants (glutathione and catalase) than those with a lower exposure to nickel; however, only glutathione showed an independent association after multivariable adjustment. Exposure to high levels of nickel may reduce serum anti-oxidative capacity.

  19. Development and characterization of protective nickel coatings by CVD process for non-ferrous metals and alloys

    International Nuclear Information System (INIS)

    Haq, A.U.

    2012-01-01

    Objective of this thesis is the formation of adhesive and corrosion resistant nickel film on aluminum, aluminum-lithium (Li 0.5 %) alloy and copper substrates by chemical vapor deposition (CVD) technique. Different surface preparation treatments such as electropolishing, anodizing and pickling are applied to the aforementioned substrates and its effect on the adhesion and corrosion resistance of nickel coating is studied. Nickel coating is deposited on different substrates by using already optimized parameters of 190-200 degree C deposition temperature, 9-8 x 10/sup -1/ Torr pressure during deposition, pure nickel-tetra-carbonyl gas, and induction heating source and 5 minutes deposition time. Substrates subjected to pickling treatment show excellent adhesion of nickel coating with a value of 5B based on ASTM standard while electropolished substrates show valve of 3B. XRD characterization of the nickel film show characteristic peaks of nickel confirming its phase purity. The SEM images show that nickel coating follows the surface features of the substrate. The pickled surface results in film with rough morphology than electropolished or anodized surface. The corrosion resistance of both uncoated and coated substrates is studied by monitoring its open circuit potential in different electrolytes (brine solution, sea and distilled water) at different temperatures. All substrates coated with nickel show 120-400mV potential difference compare with uncoated substrates in different electrolytes. (author)

  20. Oral nickel exposure may induce Type I hypersensitivity reaction in nickel-sensitized subjects.

    Science.gov (United States)

    Büyüköztürk, Suna; Gelincik, Aslı; Ünal, Derya; Demirtürk, Mustafa; Çelik, Dolay Damla; Erden, Sacide; Çolakoğlu, Bahattin; Erdem Kuruca, Serap

    2015-05-01

    Little is known about the clinical and immunological changes in the nickel allergic patients with systemic symptoms. We aimed to evaluate T helper cell responses of patients with different clinical presentations due to nickel. Patients having various allergic symptoms and positive patch test results to nickel and 20 controls underwent skin prick tests with nickel. IL-10, IL-4, IL-5 and IFN-gamma were measured in the culture supernatants of PBMC stimulated by nickel during lymphocyte proliferation test (LTT). 69 patients (56 female, mean age: 49.2 ± 13.1), 97% having nickel containing dental devices and 20 controls (8 female, mean age 34.9 ± 12.06) were evaluated. Skin prick tests with nickel were positive in 70% of the patients (pnickel. Nickel containing dental alloys and oral nickel intake seem to trigger systemic symptoms in previously nickel sensitized patients. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. The EU Nickel Directive revisited--future steps towards better protection against nickel allergy

    DEFF Research Database (Denmark)

    Thyssen, Jacob P; Uter, Wolfgang; McFadden, John

    2011-01-01

    In July 2001, the EU Nickel Directive came into full force to protect European citizens against nickel allergy and dermatitis. Prior to this intervention, Northern European governments had already begun to regulate consumer nickel exposure. According to part 2 of the EU Nickel Directive...... and the Danish nickel regulation, consumer items intended to be in direct and prolonged contact with the skin were not allowed to release more than 0.5 µg nickel/cm2/week. It was considered unlikely that nickel allergy would disappear altogether as a proportion of individuals reacted below the level defined...... by the EU Nickel Directive. Despite this, the EU Nickel Directive part 2 was expected to work as an operational limit that would sufficiently protect European consumers against nickel allergy and dermatitis. This review presents the accumulation of epidemiological studies that evaluated the possible effect...

  2. Nickel may be released from laptop computers

    DEFF Research Database (Denmark)

    Jensen, Peter; Jellesen, Morten Stendahl; Møller, Per

    2012-01-01

    Consumer nickel sensitization and dermatitis is caused by prolonged or repeated skin exposure to items that release nickel, for example jewellery, belts, buttons, watches, and mobile phones (1–3). We recently described a patient in whom primary nickel contact sensitization and dermatitis developed...... following the use of an Apple laptop computer (4). To estimate nickel release from Apple laptop computers, we investigated a random sample of 20 devices....

  3. Nickel Nanowire@Porous NiCo{sub 2}O{sub 4} Nanorods Arrays Grown on Nickel Foam as Efficient Pseudocapacitor Electrode

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Houzhao; Li, Lang; Zhang, Jun; Liu, Xiang; Wang, Hanbin; Wang, Hao, E-mail: nanoguy@126.com [Faculty of Physics and Electronic Science, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei Key Laboratory of Ferro & Piezoelectric Materials and Devices, Hubei University, Wuhan (China)

    2017-12-13

    A three dimensional hierarchical nanostructure composed of nickel nanowires and porous NiCo{sub 2}O{sub 4} nanorods arrays on the surface of nickel foam is successfully fabricated by a facile route. In this structure, the nickel nanowires are used as core materials to support high-pseudocapacitance NiCo{sub 2}O{sub 4} nanorods and construct the well-defined NiCo{sub 2}O{sub 4} nanorods shell/nickel nanowires core hierarchical structure on nickel foam. Benefiting from the participation of nickel nanowires, the nickel nanowire@NiCo{sub 2}O{sub 4}/Ni foam electrode shows a high areal specific capacitance (7.4 F cm{sup −2} at 5 mA cm{sup −2}), excellent rate capability (88.04% retained at 100 mA cm{sup −2}), and good cycling stability (74.08% retained after 1,500 cycles). The superior electrochemical properties made it promising as electrode for supercapacitors.

  4. Enhancement of porous silicon photoluminescence by electroless deposition of nickel

    Energy Technology Data Exchange (ETDEWEB)

    Amdouni, S. [Unité de nanomatériaux et photonique, Université El Manar, Faculté des Sciences de Tunis, Département de Physique, 2092 El Manar, Tunis Tunisia (Tunisia); Rahmani, M., E-mail: rahmanimehdi79@yahoo.com [Unité de nanomatériaux et photonique, Université El Manar, Faculté des Sciences de Tunis, Département de Physique, 2092 El Manar, Tunis Tunisia (Tunisia); Zaïbi, M.-A [Unité de nanomatériaux et photonique, Université El Manar, Faculté des Sciences de Tunis, Département de Physique, 2092 El Manar, Tunis Tunisia (Tunisia); Ecole Nationale Supérieure des Ingénieurs de Tunis, Université de Tunis, 5 Avenue Taha Hussein, 1008 Tunis (Tunisia); Oueslati, M. [Unité de nanomatériaux et photonique, Université El Manar, Faculté des Sciences de Tunis, Département de Physique, 2092 El Manar, Tunis Tunisia (Tunisia)

    2015-01-15

    Nickel-porous silicon nanocomposites (PS/Ni) are elaborated by an electroless deposition method using NiCl{sub 2} aqueous solution. The presence of nickel ions in the porous layer is confirmed by Fourier Transformed InfraRed spectroscopy (FTIR) and Raman spectroscopy. The photoluminescence (PL) spectra of PS/Ni, prepared at different electroless durations (t{sub edp}), are analyzed. A remarkable enhancement in the integrated PL intensity of PS containing nickel was observed. The lower t{sub edp} favor the deposition of nickel in PS, hence the silicon dangling bonds at the porous surface are quenched and this was increased the PL intensity. However, for the longer t{sub edp}, the PL intensity has been considerably decreased due to the destruction of some Si nanocrystallites. The PL spectra of PS/Ni, for t{sub edp} less than 8 min, show a multiband profile indicating the creation of new luminescent centers by Ni elements which induces a strong modification in the emission mechanisms. - Highlights: • Deposition of Ni ions into porous silicon (PS) layer using the electroless method. • Formation of Ni–O bonds on the porous layer. • The photoluminescence (PL) intensity of PS is enhanced after Ni deposition. • The increase of the PL is due to the contribution of radiative centers related to Ni.

  5. Discovery of doubly magic nickel

    CERN Document Server

    CERN. Geneva

    2000-01-01

    An experiment at the French GANIL laboratory has recently discovered a new "doubly magic" nucleus-only the tenth such isotope known to science. A collaboration of French, Polish and Romanian physicists began an experiment at GANIL in Caen, France, to search for nickel-48, the last doubly magic nucleus accessible with present methods. A primary beam of nickel-58 with an average intensity of 10 /sup 12/ ions per second and an energy of 95 MeV per nucleon hit a natural nickel target in the superconducting solenoids of the SISSI device. The proton-rich projectile fragments were selected by the USE3 separator and finally identified by their time of flight, their energy loss and their total energy in a detection set-up consisting of a microchannel plate detector and a stack of five silicon detectors. This allowed the measurement of 10 independent parameters to identify each fragment arriving at the focal plane. (0 refs).

  6. Investigation of hydrogen evolution activity for the nickel, nickel-molybdenum nickel-graphite composite and nickel-reduced graphene oxide composite coatings

    International Nuclear Information System (INIS)

    Jinlong, Lv; Tongxiang, Liang; Chen, Wang

    2016-01-01

    Graphical abstract: - Highlights: • Improved HER efficiency of Ni-Mo coatings was attributed to ‘cauliflower’ like microstructure. • RGO in nickel-RGO composite coating promoted refined grain and facilitated HER. • Synergistic effect between nickel and RGO facilitated HER due to large specific surface of RGO. - Abstract: The nickel, nickel-molybdenum alloy, nickel-graphite and nickel-reduced graphene oxide composite coatings were obtained by the electrodeposition technique from a nickel sulfate bath. Nanocrystalline molybdenum, graphite and reduced graphene oxide in nickel coatings promoted hydrogen evolution reaction in 0.5 M H 2 SO 4 solution at room temperature. However, the nickel-reduced graphene oxide composite coating exhibited the highest electrocatalytic activity for the hydrogen evolution reaction in 0.5 M H 2 SO 4 solution at room temperature. A large number of gaps between ‘cauliflower’ like grains could decrease effective area for hydrogen evolution reaction in slight amorphous nickel-molybdenum alloy. The synergistic effect between nickel and reduced graphene oxide promoted hydrogen evolution, moreover, refined grain in nickel-reduced graphene oxide composite coating and large specific surface of reduced graphene oxide also facilitated hydrogen evolution reaction.

  7. Investigation of hydrogen evolution activity for the nickel, nickel-molybdenum nickel-graphite composite and nickel-reduced graphene oxide composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Jinlong, Lv, E-mail: ljlbuaa@126.com [Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Zhongguancun Street, Haidian District, Beijing 100084 (China); State Key Lab of New Ceramic and Fine Processing, Tsinghua University, Beijing 100084 (China); Tongxiang, Liang; Chen, Wang [Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Zhongguancun Street, Haidian District, Beijing 100084 (China); State Key Lab of New Ceramic and Fine Processing, Tsinghua University, Beijing 100084 (China)

    2016-03-15

    Graphical abstract: - Highlights: • Improved HER efficiency of Ni-Mo coatings was attributed to ‘cauliflower’ like microstructure. • RGO in nickel-RGO composite coating promoted refined grain and facilitated HER. • Synergistic effect between nickel and RGO facilitated HER due to large specific surface of RGO. - Abstract: The nickel, nickel-molybdenum alloy, nickel-graphite and nickel-reduced graphene oxide composite coatings were obtained by the electrodeposition technique from a nickel sulfate bath. Nanocrystalline molybdenum, graphite and reduced graphene oxide in nickel coatings promoted hydrogen evolution reaction in 0.5 M H{sub 2}SO{sub 4} solution at room temperature. However, the nickel-reduced graphene oxide composite coating exhibited the highest electrocatalytic activity for the hydrogen evolution reaction in 0.5 M H{sub 2}SO{sub 4} solution at room temperature. A large number of gaps between ‘cauliflower’ like grains could decrease effective area for hydrogen evolution reaction in slight amorphous nickel-molybdenum alloy. The synergistic effect between nickel and reduced graphene oxide promoted hydrogen evolution, moreover, refined grain in nickel-reduced graphene oxide composite coating and large specific surface of reduced graphene oxide also facilitated hydrogen evolution reaction.

  8. Void formation in irradiated binary nickel alloys

    International Nuclear Information System (INIS)

    Shaikh, M.A.; Ahmed, M.; Akhter, J.I.

    1994-01-01

    In this work a computer program has been used to compute void radius, void density and swelling parameter for nickel and binary nickel-carbon alloys irradiated with nickel ions of 100 keV. The aim is to compare the computed results with experimental results already reported

  9. Improved nickel plating of Inconel X-750

    Science.gov (United States)

    Farmer, M. E.; Feeney, J. E.; Kuster, C. A.

    1969-01-01

    Electroplating technique with acid pickling provides a method of applying nickel plating on Inconel X-750 tubing to serve as a wetting agent during brazing. Low-stress nickel-plating bath contains no organic wetting agents that cause the nickel to blister at high temperatures.

  10. Pulse electrodeposited nickel using sulphamate electrolyte for hardness and corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Sivasakthi, P.; Sekar, R.; Bapu, G.N.K.Ramesh, E-mail: bapu2657@yahoo.com

    2015-10-15

    Highlights: • Nickel deposits from sulphamate solutions using pulse method are prepared. • Effect of duty cycle and frequency are studied. • XRD, SEM and AFM of the nickel deposits are characterized. • Corrosion characteristics of the nickel deposit are reported. - Abstract: Nickel deposits have been obtained on mild steel substrate by pulse current (PC) electrodeposition method using nickel sulphamate electrolyte. Micro hardness values increased with decreasing duty cycle and pulse frequency. X-ray diffraction studies revealed that (2 0 0) plane was predominant and the nickel deposit obtained at low duty cycle and low frequency has the smallest grain size. The surface morphology of the coatings was explored by scanning electron microscopy (SEM) and atomic force microscopy. These studies showed that the microstructure of the nickel coatings changed from pyramidal structure to homogeneous structure with increasing duty cycle and pulse frequencies. The corrosion resistance of coatings was evaluated by potentiodynamic polarization and electrochemical impedance studies in 3.5 wt% sodium chloride (NaCl) solutions. An enhancement of the corrosion resistance, charge-transfer resistance and wear resistance has been obtained at low duty cycle and low frequencies.

  11. Synthesis and growth mechanism of sponge-like nickel using a hydrothermal method

    Science.gov (United States)

    Shao, Bin; Yin, Xueguo; Hua, Weidong; Ma, Yilong; Sun, Jianchun; Li, Chunhong; Chen, Dengming; Guo, Donglin; Li, Kejian

    2018-05-01

    Sponge-like nickel composed of micro-chains with a diameter of 1-5 μm was selectively synthesized by the hydrothermal method, using sodium hydroxide (NaOH) as the alkaline reagent, aqueous hydrazine as reducing agent and citric acid as a coordination agent. The time-dependent samples prepared at different NaOH concentrations were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR). The results showed that the agglomerates of nickel citrate hydrazine complex nanoplates were first precipitated and then reduced to prickly nickel micro-chains at a lower NaOH concentration, which played a role in the further formation of sponge-like nickel. Also, the probable growth mechanism of the sponge-like nickel was proposed. The magnetic properties of sponge-like nickel were studied using a vibrating sample magnetometer. The sponge-like nickel exhibited a ferromagnetic behavior with a saturation magnetization value of 43.8 emu g-1 and a coercivity value of 120.7 Oe.

  12. Molecular Mechanisms of Nickel Allergy.

    Science.gov (United States)

    Saito, Masako; Arakaki, Rieko; Yamada, Akiko; Tsunematsu, Takaaki; Kudo, Yasusei; Ishimaru, Naozumi

    2016-02-02

    Allergic contact hypersensitivity to metals is a delayed-type allergy. Although various metals are known to produce an allergic reaction, nickel is the most frequent cause of metal allergy. Researchers have attempted to elucidate the mechanisms of metal allergy using animal models and human patients. Here, the immunological and molecular mechanisms of metal allergy are described based on the findings of previous studies, including those that were recently published. In addition, the adsorption and excretion of various metals, in particular nickel, is discussed to further understand the pathogenesis of metal allergy.

  13. Molecular Mechanisms of Nickel Allergy

    Directory of Open Access Journals (Sweden)

    Masako Saito

    2016-02-01

    Full Text Available Allergic contact hypersensitivity to metals is a delayed-type allergy. Although various metals are known to produce an allergic reaction, nickel is the most frequent cause of metal allergy. Researchers have attempted to elucidate the mechanisms of metal allergy using animal models and human patients. Here, the immunological and molecular mechanisms of metal allergy are described based on the findings of previous studies, including those that were recently published. In addition, the adsorption and excretion of various metals, in particular nickel, is discussed to further understand the pathogenesis of metal allergy.

  14. Ecological Considerations on Nickel Dermatitis

    Science.gov (United States)

    Marcussen, Poul V.

    1960-01-01

    The incidence of nickel dermatoses has shifted from the plating industry to other occupations and particularly to non-occupational causes. A Danish survey of 621 cases shows that 4% are due to nickel plating, 9·5% to other occupations, and 86·5% were not due to occupation. A primary eruption not due to occupation had occurred in 14% of the occupational cases. The importance of preventive measures for the community more than for the adequately controlled industry is underlined. PMID:14420983

  15. Nickel catalyst supported on magnesium and zinc aluminates (MgAl{sub 2}O{sub 4} and ZnAl{sub 2}O{sub 4}) spinels for dry reforming of methane

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, L.C.B. de; Melo, D.M. de A.; Melo, M.A. de F.; Barros, J.M. de F.; Braga, R.M.; Costa, C. de C.; Rodrigues, G., E-mail: ieda.garcia@pq.cnpq.br [Universidade Federal da Paraiba (LACOM/UFPB), Joao Pessoa, PB (Brazil). Dept. de Quimica

    2017-01-15

    Materials such as MgAl{sub 2}O{sub 4} and ZnAl{sub 2}O{sub 4} assessed in the reaction of dry reforming of methane to produce syngas were synthesized by microwave-assisted combustion method using urea as fuel. Samples of synthesized oxides were calcined at 800 °C for 2 h and impregnated with 5% nickel. The impregnated samples were calcined at 850 °C for 4 h to obtain the desired phases. The results of the catalytic tests showed that the catalysts are active for the reaction of dry reforming of methane, and the catalyst that showed the best performance for methane conversion was 5% Ni/MgAl{sub 2}O{sub 4} calcined at 850 °C/4 h. (author)

  16. Preparation and Characterization of Cu and Ni on Alumina Supports and Their Use in the Synthesis of Low-Temperature Metal-Phthalocyanine Using a Parallel-Plate Reactor

    Directory of Open Access Journals (Sweden)

    Carlos J. Lucio-Ortiz

    2013-09-01

    Full Text Available Ni- and Cu/alumina powders were prepared and characterized by X-ray diffraction (XRD, scanning electronic microscope (SEM, and N2 physisorption isotherms were also determined. The Ni/Al2O3 sample reveled agglomerated (1 μm of nanoparticles of Ni (30–80 nm however, NiO particles were also identified, probably for the low temperature during the H2 reduction treatment (350 °C, the Cu/Al2O3 sample presented agglomerates (1–1.5 μm of nanoparticles (70–150 nm, but only of pure copper. Both surface morphologies were different, but resulted in mesoporous material, with a higher specificity for the Ni sample. The surfaces were used in a new proposal for producing copper and nickel phthalocyanines using a parallel-plate reactor. Phthalonitrile was used and metallic particles were deposited on alumina in ethanol solution with CH3ONa at low temperatures; ≤60 °C. The mass-transfer was evaluated in reaction testing with a recent three-resistance model. The kinetics were studied with a Langmuir-Hinshelwood model. The activation energy and Thiele modulus revealed a slow surface reaction. The nickel sample was the most active, influenced by the NiO morphology and phthalonitrile adsorption.

  17. A facile method for the preparation of Covalent Triazine Framework coated monoliths as catalyst support - applications in C1 catalysis

    KAUST Repository

    Bavykina, Anastasiya V.

    2017-07-17

    A quasi Chemical Vapour Deposition method for the manufacturing of well-defined Covalent Triazine Framework (CTF) coatings on cordierite monoliths is reported. The resulting supported porous organic polymer is an excellent support for the immobilisation of two different homogeneous catalysts: 1) an IrIIICp*-based catalyst for the hydrogen production from formic acid, and 2) a PtII-based for the direct activation of methane via Periana chemistry. The immobilised catalysts display a much higher activity in comparison with the unsupported CTF operated in slurry because of improved mass transport. Our results demonstrate that CTF based catalysts can be further optimised by engineering at different length-scales.

  18. Electrocatalysts with platinum, cobalt and nickel preparations by mechanical alloyed and CVD for the reaction of oxygen reduction; Electrocatalizadores a base de platino, cobalto y niquel preparados por aleado mecanico y CVD para la reaccion de reduccion de oxigeno

    Energy Technology Data Exchange (ETDEWEB)

    Garcia C, M. A. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)

    2008-07-01

    In this research, the molecular oxygen reduction reaction (ORR) was investigated on electrocatalysts of Co, Ni, Pt and their alloys CoNi, PtCo, PtNi and PtCoNi by using H{sub 2}SO{sub 4} 0.5 and KOH 0.5 M solutions as electrolytes. The electrocatalysts were synthesized by Mechanical Alloying (MA) and Chemical Vapor Deposition (CVD) processes. For MA, metallic powders were processed during 20 h of milling in a high energy SPEX 8000 mill. For CVD, a hot-wall reactor was utilized and Co, Ni and Pt acetilactetonates were used as precursors. Films were deposited at a total pressure of 1 torr and temperatures of 400-450 C. Electrocatalysts were characterized by X-Ray Diffraction (XRD). Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Energy Dispersive X-Ray Spectroscopy (EDS). Electrocatalysts prepared by mechanical alloying showed a homogeneously dispersed agglomeration of particles with nano metric size. Electrocatalysts obtained by CVD showed, in some cases, non uniform films, with particles of nano metric size, as well. The electrocatalytic performance was evaluated by using the Rotating Disk Electrode technique (RDE). Electrocatalysts prepared by MA showed higher activity than those obtained by CVD. All electrocatalysts were evaluated in alkaline media. Only electrocatalysts containing Pt were evaluated in acid media, because those materials with Co, Ni and their alloys showed instability in acidic media. Most electrocatalysts followed a mechanism for the ORR producing a certain proportion of H{sub 2}O{sub 2}. All electrocatalysts, exhibited a fair or good electrocatalytic activity in comparison with other similar reported materials. It was found that MA and CVD are appropriate processes to prepare electrocatalysts for the ORR with particles of nano metric size and performing with an acceptable catalytic activity. PtCoNi 70-23-7% by MA and PtCoNi-CVD electrocatalysts showed the highest activity in alkaline media, while in acidic

  19. Nickel exposure from keys: a Brazilian issue.

    Science.gov (United States)

    Suzuki, Nathalie Mie; Duarte, Ida Alzira Gomes; Hafner, Mariana de Figueiredo Silva; Lazzarini, Rosana

    2017-01-01

    Keys are a significant source of exposure to metal allergens and can be a relevant problem for nickel-allergic individuals. This study aimed to perform nickel and cobalt spot testing among the 5 most common Brazilian brands of keys. Among the tested keys, 100% showed positive result to nickel spot test, 83,3% presented strong positive reaction. 50% exhibited cobalt release as well. Nickel release from keys is very common in our country and may cause a negative impact on sensitized individual's quality of life. Study's results highlight the importance of establishing directives to regulate nickel release in Brazil.

  20. Field Test of a DCVD Using an Ixon Camera with a Lumogen-Coated EMCCD Detector. Prepared for the Canadian Safeguards Support Program and the Swedish Support Program

    International Nuclear Information System (INIS)

    Chen, J.D.; Gerwing, A.F.; Maxwell, R.; Larsson, M.; Axell, K.; Hildingsson, L.; Lindberg, B.; Vinnaa, F.

    2003-12-01

    The Canadian and Swedish Safeguards Support Programs have developed a new digital Cerenkov viewing device (DCVD) to verify spent fuel. The new system, based upon an electron-multiplied charge-coupled device that is lumogen coated, can operate at 14 frames per second using the fast 5 MHz analogue to digital converter. The new DCVD was successful in measuring the long-cooled Aagesta fuel with a burnup of 1,200 MWd/t U and a cooling time of 31 years, which is well below the target of 10,000 MWd/t U and 40- years- cooled. Scanning of fuel assemblies was successfully demonstrated. With the aid of a laser pointer system, random verification within a reasonable time frame was also demonstrated

  1. Preparation, Clinical Support, and Confidence of Speech-Language Therapists Managing Clients with a Tracheostomy in the UK

    Science.gov (United States)

    Ward, Elizabeth; Morgan, Tessa; McGowan, Sue; Spurgin, Ann-Louise; Solley, Maura

    2012-01-01

    Background: Literature regarding the education, training, clinical support and confidence of speech-language therapists (SLTs) working with patients with a tracheostomy is limited; however, it suggests that many clinicians have reduced clinical confidence when managing this complex population, many face role and team challenges practising in this…

  2. High-activity MgO-supported CoMo Hydrodesulfurization Catalysts Prepared by Non-aqueous Impregnation

    Czech Academy of Sciences Publication Activity Database

    Kaluža, Luděk; Gulková, Daniela; Vít, Zdeněk; Zdražil, Miroslav

    2015-01-01

    Roč. 162, JAN 2015 (2015), s. 430-436 ISSN 0926-3373 R&D Projects: GA ČR GAP106/11/0902 Institutional support: RVO:67985858 Keywords : CoMo/MgO * benzothiophene hydrodesulfurization * non-aqueous impregnation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 8.328, year: 2015

  3. Relative Activity of Niobia-Supported CoMo Hydrodesulphurization Catalyst Prepared with NTA: A Kinetic Approach.

    Czech Academy of Sciences Publication Activity Database

    Kaluža, Luděk; Zdražil, Miroslav

    2018-01-01

    Roč. 107 (2018), s. 62-67 ISSN 1566-7367 R&D Projects: GA ČR GA17-22490S Institutional support: RVO:67985858 Keywords : Niobia * hydrodesulphurization * CoMo Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 3.330, year: 2016

  4. Water- and organo-dispersible gold nanoparticles supported by using ammonium salts of hyperbranched polystyrene: preparation and catalysis.

    Science.gov (United States)

    Gao, Lei; Nishikata, Takashi; Kojima, Keisuke; Chikama, Katsumi; Nagashima, Hideo

    2013-12-01

    Gold nanoparticles (1 nm in size) stabilized by ammonium salts of hyperbranched polystyrene are prepared. Selection of the R groups provides access to both water- and organo-dispersible gold nanoparticles. The resulting gold nanoparticles are subjected to studies on catalysis in solution, which include reduction of 4-nitrophenol with sodium borohydride, aerobic oxidation of alcohols, and homocoupling of phenylboronic acid. In the reduction of 4-nitrophenol, the catalytic activity is clearly dependent on the size of the gold nanoparticles. For the aerobic oxidation of alcohols, two types of biphasic oxidation are achieved: one is the catalyst dispersing in the aqueous phase, whereas the other is in the organic phase. The catalysts are reusable more than four times without loss of the catalytic activity. Selective synthesis of biphenyl is achieved by the homocoupling of phenylboronic acid catalyzed by organo-dispersible gold nanoparticles. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Preparation and Characterization of Zirconia-Coated Nanodiamonds as a Pt Catalyst Support for Methanol Electro-Oxidation

    Directory of Open Access Journals (Sweden)

    Jing Lu

    2016-12-01

    Full Text Available Zirconia-coated nanodiamond (ZrO2/ND electrode material was successfully prepared by one-step isothermal hydrolyzing from ND-dispersed ZrOCl2·8H2O aqueous solution. High-resolution transmission electron microscopy reveals that a highly conformal and uniform ZrO2 shell was deposited on NDs by this simple method. The coating obtained at 90 °C without further calcination was mainly composed of monoclinic nanocrystalline ZrO2 rather than common amorphous Zr(OH4 clusters. The ZrO2/NDs and pristine ND powder were decorated with platinum (Pt nanoparticles by electrodeposition from 5 mM chloroplatinic acid solution. The electrochemical studies indicate that Pt/ZrO2/ND catalysts have higher electrocatalytic activity and better stability for methanol oxidation than Pt/ND catalysts in acid.

  6. Assaying environmental nickel toxicity using model nematodes

    Science.gov (United States)

    Rudel, David; Douglas, Chandler; Huffnagle, Ian; Besser, John M.; Ingersoll, Christopher G.

    2013-01-01

    Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water), we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegansand P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species.

  7. Assaying environmental nickel toxicity using model nematodes.

    Directory of Open Access Journals (Sweden)

    David Rudel

    Full Text Available Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water, we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegans and P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species.

  8. Assaying environmental nickel toxicity using model nematodes.

    Science.gov (United States)

    Rudel, David; Douglas, Chandler D; Huffnagle, Ian M; Besser, John M; Ingersoll, Christopher G

    2013-01-01

    Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water), we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegans and P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species.

  9. Iron-nickel-chromium alloys

    International Nuclear Information System (INIS)

    Karenko, M.K.

    1981-01-01

    A specification is given for iron-nickel-chromium age-hardenable alloys suitable for use in fast breeder reactor ducts and cladding, which utilize the gamma-double prime strengthening phase and are characterized in having a delta or eta phase distributed at or near grain boundaries. A range of compositions is given. (author)

  10. Electrolytic nickel deposits upon uranium

    International Nuclear Information System (INIS)

    Baudin, G.; Chauvin, G.; Coriou, H.; Hure, J.

    1958-01-01

    The authors present a new possibility to protect uranium by very adherent nickel deposits got by aqueous medium electrolysis. Surface treatment of uranium is based upon the chemical etching method from Lietazke. After thermal treatments at 600, 700 and 800 deg. C, under vacuum, a good intermetallic U-Ni diffusion is observed for each case. (author) [fr

  11. Heat treatment of nickel alloys

    International Nuclear Information System (INIS)

    Smith, D.F. Jr.; Clatworthy, E.F.

    1975-01-01

    A heat treating process is described that can be used to produce desired combinations of strength, ductility, and fabricability characteristics in heat resistant age-hardenable alloys having precipitation-hardening amounts of niobium, titanium, and/or tantalum in a nickel-containing matrix. (U.S.)

  12. Coin exposure may cause allergic nickel dermatitis

    DEFF Research Database (Denmark)

    Thyssen, Jacob P; Gawkrodger, David J; White, Ian R

    2012-01-01

    Nickel is used in coins because the metal has beneficial properties, including price, colour, weight, and corrosion resistance, and also because it is easy to stamp. It has often been claimed that the duration of skin contact with coins is too short to cause nickel release and dermatitis. However......, it is well known by dermatologists specialized in occupational skin diseases, and by their nickel-allergic patients, that hand eczema in cashiers and other professionals who handle coins may be caused or aggravated by nickel release from coins. In this review, we present evidence from past studies showing...... that nickel-containing coins can indeed pose a risk for those who handle them. For protection of the health of consumers, cashiers, and other workers who handle coins, it is suggested that coins without nickel release should be used as a substitute for the high nickel-releasing coins currently in widespread...

  13. Geochemical prospecting for copper and nickel in the Wulgai and Tor Tangi areas southeast of Hindubagh, Quetta Division, Pakistan

    Science.gov (United States)

    Stanin, S. Anthony; Wahid, M.A.; Khan, Shamsher

    1975-01-01

    Showings of magnetite, copper, and possible nickel mineralization in the Hindubagh chromite mining district are near Wulgai and Tor Tangi. Several hundred samples of clastic material from dry streambeds in these areas were sieved for the minus-80-mesh fraction and analyzed for copper using 2, 2'-biquinoline and for nickel using alpha-furildioxime. The copper threshold is 75 ppm, and the nickel threshold is 400 ppm. A geochemical map has been prepared that shows nine areas of anomalously high copper and six areas of high nickel. The nickel anomalies may represent secondary dispersion patterns derived from the erosion of nickeliferous ultramafic rocks of the Hindubagh intrusive complex. Copper showings in and near four of the anomalous copper areas indicate that detailed geological investigation and detailed geochemical sampling of rocks, soil, and unconsolidated clastic material are required to determine the source of the anomalies.

  14. Influence of Surface Pretreatment on the Corrosion Resistance of Cold-Sprayed Nickel Coatings in Acidic Chloride Solution

    Science.gov (United States)

    Scendo, Mieczyslaw; Zorawski, Wojciech; Staszewska-Samson, Katarzyna; Makrenek, Medard; Goral, Anna

    2018-03-01

    Corrosion resistance of the cold-sprayed nickel coatings deposited on the Ni surface (substrate) without and with abrasive grit-blasting treatment of the substrate was investigated. The corundum powder with different grain sizes was used. The corrosive environment contained an acidic chloride solution. The mechanism of the corrosion of nickel was suggested and discussed. Corrosion electrochemical parameters were determined by electrochemical methods. The corrosion effect of a nickel coating depends on the grain size used to prepare the substrate. The nickel coating after the medium grit-blasting treatment of the substrate was found to be the most corrosion resistant. However, the smallest resistance on the corrosion effect should be attributed to the nickel coating on the substrate after the coarse grit-blasting treatment.

  15. The EU Nickel Directive revisited--future steps towards better protection against nickel allergy

    DEFF Research Database (Denmark)

    Thyssen, Jacob P; Uter, Wolfgang; McFadden, John

    2011-01-01

    In July 2001, the EU Nickel Directive came into full force to protect European citizens against nickel allergy and dermatitis. Prior to this intervention, Northern European governments had already begun to regulate consumer nickel exposure. According to part 2 of the EU Nickel Directive...... of this major public health intervention. Also, it evaluates recent exposure assessment studies that have been performed using the dimethyl glyoxime test. It is concluded that the EU Nickel Directive has started to change the epidemiology of nickel allergy in Europe but it should be revisited to better protect...... and the Danish nickel regulation, consumer items intended to be in direct and prolonged contact with the skin were not allowed to release more than 0.5 µg nickel/cm2/week. It was considered unlikely that nickel allergy would disappear altogether as a proportion of individuals reacted below the level defined...

  16. Prevalence of nickel allergy in Europe following the EU Nickel Directive - a review

    DEFF Research Database (Denmark)

    Ahlström, Malin G; Thyssen, Jacob P; Menné, Torkil

    2017-01-01

    Nickel contact allergy remains a problem in EU countries, despite the EU Nickel Directive. To study the prevalence of nickel allergy in EU countries following the implementation of the EU Nickel Directive, we performed a systematic search in PubMed for studies that examined the prevalence of nickel...... allergy in EU countries published during 2005-2016. We identified 46 studies: 10 in the general population and 36 in patch tested dermatitis patients. A significantly lower prevalence of nickel allergy after than before the implementation of the EU Nickel Directive was found in women aged 18-35 years (11......, and generally remained high, affecting 8-18% of the general population. A consistent pattern of decreasing prevalence of nickel allergy in some EU countries was observed, although the prevalence among young women remains high. Steps should be taken for better prevention of nickel allergy in EU countries....

  17. Nickel in nails, hair and plasma from nickel-hypersensitive women

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Veien, Niels

    1990-01-01

    The concentrations of nickel in finger-nails, toe-nails, hair and plasma from 71 nickel-hypersensitive women and 20 non-hypersensitive women were determined. Nickel concentrations in finger-nails were significantly higher than in toe-nails in both the nickel-hypersensitive group and the control...... group. Nickel-sensitive women had significantly higher levels of nickel in toe-nails, hair and plasma than had control subjects, whereas there was no significant difference in nickel concentration in finger-nails between the two groups. No correlation could be demonstrated between nickel levels in any...... combination of nails, hair and plasma in the nickel-hypersensitive or in the control group....

  18. Excessive nickel release from mobile phones--a persistent cause of nickel allergy and dermatitis.

    Science.gov (United States)

    Jensen, Peter; Johansen, Jeanne D; Zachariae, Claus; Menné, Torkil; Thyssen, Jacob P

    2011-12-01

    Despite the political intention to limit nickel allergy and dermatitis in Europeans, nickel allergy remains frequent. There are several explanations for the persistence of nickel allergy and dermatitis, including the increasing use of mobile phones. Before regulation of nickel release from mobile phones, we showed that eight (19.5%) of 41 mobile phones marketed in Denmark between 2003 and 2007 released nickel in concentrations that may result in nickel allergy and dermatitis. In 2009, the EU Nickel Directive was revised to include nickel-releasing mobile phones. To investigate the proportion of mobile phones sold in Denmark that release nickel after regulation. Metallic parts from 50 randomly selected mobile phones currently for sale in Denmark were tested for nickel release by use of the dimethylglyoxime (DMG)-nickel spot test. Nine (18%) phones showed at least one positive DMG test reaction and two phones had more than one DMG test-positive spot. Apparently, the proportion of mobile phones with significant nickel release remains unchanged, despite the 2009 revision of the EU Nickel Directive. We encourage manufacturers to measure nickel release from metallic components used in the assembly of mobile phones to ensure safe products. © 2011 John Wiley & Sons A/S.

  19. A biotemplated nickel nanostructure: Synthesis, characterization and antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Ashtari, Khadijeh [Department of Nanobiotechnology, Faculty of Biological Science, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Fasihi, Javad [Department of Analytical Chemistry, Faculty of Science, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mollania, Nasrin [Department of Biochemistry, Faculty of Biological Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran (Iran, Islamic Republic of); Khajeh, Khosro, E-mail: khajeh@modares.ac.ir [Department of Nanobiotechnology, Faculty of Biological Science, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Department of Biochemistry, Faculty of Biological Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran (Iran, Islamic Republic of)

    2014-02-01

    Highlights: • Nickel nanostructure-encapsulated bacteria were prepared using electroless deposition. • Bacterium surface was activated by red-ox reaction of its surface amino acids. • Interfacial changes at cell surfaces were investigated using fluorescence spectroscopy. • TEM and AFM depicted morphological changes. • Antibacterial activity of nanostructure was examined against different bacteria strains. - Abstract: Nickel nanostructure-encapsulated bacteria were prepared using the electroless deposition procedure and activation of bacterium cell surface by red-ox reaction of surface amino acids. The electroless deposition step occurred in the presence of Ni(II) and dimethyl amine boran (DMAB). Interfacial changes at bacteria cell surfaces during the coating process were investigated using fluorescence spectroscopy. Fluorescence of tryptophan residues was completely quenched after the deposition of nickel onto bacteria surfaces. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) depicted morphological changes on the surface of the bacterium. It was found that the Ni coated nanostructure was mechanically stable after ultrasonication for 20 min. Significant increase in surface roughness of bacteria was also observed after deposition of Ni clusters. The amount of coated Ni on the bacteria surface was calculated as 36% w/w. The antibacterial activity of fabricated nanostructure in culture media was examined against three different bacteria strains; Escherichia coli, Bacillus subtilis and Xantomonas campestris. The minimum inhibitory concentrations (MIC) were determined as 500 mg/L, 350 mg/L and 200 mg/L against bacteria, respectively.

  20. Nickel production in Serbia-technological and environmental aspects

    Directory of Open Access Journals (Sweden)

    Željko Kamberović

    2014-12-01

    Full Text Available Demand for nickel is constantly growing due to the versatility of its application, at the first place for stainless steel production. Ore reserves and possibility of nickel production of today’s Serbia and in neighboring countries were thoroughly investigated, and presented work is part of a wider project of sublimation of scientific and professional experience in the field of nickel extractive metallurgy on domestic raw materials. Presented research explores the possibility of high pressure sulfuric acid leaching of Serbian lateritic ores from localities Rudjinci, Ba and Lipovac. All three investigated ore deposits behaved differently both during preparation and during hydrometallurgical treatment. As optimal method for ore preparation proved to be crushing-milling-sieving route, but without possibility of concentrate production. Only for Rudjinci ore deposit achieved leaching efficiency reached satisfactory level of 95%. Within presented paper flow-sheet is proposed for processing high-magnesium laterite ores, with iron and magnesium oxide Both could be recirculated and used again in technological process; MgO for iron precipitation and SO2 for production of leaching agent, sulfuric acid. Final decision on the sustainability of the process will be made according to techno-economic and environmental evaluation. Estimated overall impact of the project implementation on the environment is negative.

  1. Characterization of composite metal-ceramic of nickel-oxide cerium doped gadolinium

    International Nuclear Information System (INIS)

    Silva, M.L.A. da; Varela, M.C.R.S.

    2016-01-01

    Composite nickel doped cerium oxide are used in SOFC anode materials. In this study we evaluated the effect of the presence of gadolinium on the properties of composite nickel and ceria and. The supports were synthesized by sol-gel method. The impregnation with nickel nitrate was taken sequentially, followed by calcination. The materials were characterized by X-ray diffraction, measurement of specific surface area, temperature programmed reduction, Raman spectroscopy. The presence of gadolinium retained the fluorite structure of ceria by forming a solid solution, also not influencing significantly on the specific surface area of the support. On the other hand, there was a decrease in the area catalysts, which can be attributed to sintering of nickel. Furthermore, addition of gadolinium favored the formation of intrinsic and extrinsic vacancies in cerium oxide, which leads to an increase in the ionic conductivity of the solid, desirable property for an SOFC anode catalyst. (author)

  2. Criteria for preparation and evaluation of radiological emergency response plans and preparedness in support of nuclear power plants. Interim report

    International Nuclear Information System (INIS)

    1980-01-01

    The purpose of this document is to provide a common reference and interim guidance source for: state and local governments and nuclear facility operators in the development of radiological emergency response plans and preparedness in support of nuclear power plants; and Nuclear Regulatory Commission (NRC), Federal Emergency Management Agency (FEMA) and other Federal agency personnel engaged in the review of state, local government, and licensee plans and preparedness

  3. Preparation of asymmetrically nanoparticle-supported, monodisperse composite dumbbells by protruding a smooth polymer bulge from rugged spheres.

    Science.gov (United States)

    Nagao, Daisuke; Goto, Kanako; Ishii, Haruyuki; Konno, Mikio

    2011-11-01

    A novel method is proposed to create asymmetrically nanoparticle-supported, monodisperse composite dumbbells. The method consists of the three steps of double soap-free emulsion polymerizations before and after a heterocoagulation. In the first step, soap-free emulsion polymerization was conducted to cover silica cores with cross-linked poly(methyl methacrylate) (PMMA) shells. Then, positively or negatively charged silica nanoparticles were heterocoagulated with the silica-PMMA core-shell particles. In the heterocoagulations, the nanoparticles surface-modified with a cationic silane coupling agent, 3-aminopropyltriethoxysilane, were used as the positively charged ones, and silica nanoparticles without any treatment were used as the negatively charged ones. In the third step, soap-free polymerizations at different pH values were performed to protrude a polystyrene (PSt) bulge from the core-shell particles supporting the charged silica nanoparticles. In the polymerization, the core-shell particles heterocoagulated with the positively charged silica nanoparticles were aggregated in an acidic condition whereas the silica nanoparticles supported on the core-shell particles were dissolved in a basic condition. For the negatively charged silica nanoparticle, a PSt bulge was successfully protruded from the core-shell particle in acidic and neutral conditions without aggregation of the core-shell particles. The protrusion of the PSt bulge became distinctive when the number of heterocoagulated silica nanoparticles per core-shell particle was increased. Additional heterocoagulation experiments, in which positively or negatively charged magnetite nanoparticles were mixed with the asymmetrically nanoparticle-supported composite dumbbells, confirmed direct exposure of silica nanoparticles to the outer solvent phase.

  4. Crumpled rGO-supported Pt-Ir bifunctional catalyst prepared by spray pyrolysis for unitized regenerative fuel cells

    Science.gov (United States)

    Kim, In Gyeom; Nah, In Wook; Oh, In-Hwan; Park, Sehkyu

    2017-10-01

    Three-dimensional (3D) crumpled reduced graphene oxide supported Pt-Ir alloys that served as bifunctional oxygen catalysts for use in untized regenerative fuel cells were synthesized by a facile spray pyrolysis method. Pt-Ir catalysts supported on rGO (Pt-Ir/rGOs) were physically characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) to observe change in composition by heat treatment, alloying, and morphological transition of the catalysts. Their catalytic activities and stabilities for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) conditions were electrochemically investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV), potential cycling and hold tests on the rotating disk electrode (RDE). Pt-Ir/rGO with no post heat-treatment (Pt-Ir/rGO_NP) showed a lower activity for ORR and OER although metal nanoparticles decorated on the support are relatively small. However, Pt-Ir/rGO showed remarkably enhanced activity following heat treatment, depending on temperature. Pt-Ir/rGO heat-treated at 600 °C after spray pyrolysis (Pt-Ir/rGO_P600) exhibited a higher activity and stability than a commercially available Pt/C catalyst kept under the ORR condition, and it also revealed a comparable OER activity and durability versus the commercial unsupported Ir catalyst.

  5. Polymer support immobilized acidic ionic liquid: Preparation and its application as catalyst in the synthesis of hantzsch 1,4-dihydro pyridines

    Energy Technology Data Exchange (ETDEWEB)

    Jahanbin, Bentolhoda; Davoodnia, Abolghasem; Behmadi, Hossein; Tavakoli Hoseini, Niloofar [Islamic Azad Univ., Mashhad (Iran, Islamic Republic of)

    2012-07-15

    A polymer support immobilized acidic ionic liquid was prepared by copolymerization of 3-vinyl-1-(4-sulfonic acid)butyl imidazolium hydrogen sulfate with styrene in the presence of benzoyl peroxide and its primary application as a solid acidic heterogeneous catalyst to the synthesis of Hantzsch 1,4-dihydro pyridines through a one-pot three-component reaction of aromatic aldehydes, ethyl acetoacetate and ammonium acetate was investigated. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and a considerable catalytic activity still could be achieved after third run.

  6. Pre-shipment preparations at the Savannah River Site - WSRC's technical basis to support DOE's approval to ship

    International Nuclear Information System (INIS)

    Thomas, Jay E.; Bickley, Donald W.; Conatser, E. Ray

    2000-01-01

    In the first four years of the Foreign Research Reactor (FRR) Spent Nuclear Fuel (SNF) Return Program following resumption of the SNF return program with the DOE-EIS ROD in May 1996, 13 shipments involving 77 casks with over 2,600 assemblies have been safely received and stored at the Savannah River Site (SRS). Each fuel type has gone through a rigorous pre-shipment preparation process that includes fuel characterization, criticality safety reviews, and operational reviews, culminating in the Department of Energy's (DOE's) authorization to ship. Ideally, the authorization to ship process should begin two years in advance of the fuel receipt with an agreement between the Department of Energy - Head Quarters (DOE-HQ) and the research reactor government on the conditions and protocol for the spent nuclear fuel return, with a target of DOE shipment authorization at least two months before facility loading. A visit by representatives from the Department of Energy - Savannah River (DOE-SR) and Westinghouse Savannah River Company (WSRC), DOE's Management and Operations (M and O) Contractor for the SRS, to the research reactor facility is then scheduled for the purpose of finalizing contractual arrangements (DOE-SR), facility assessments, and initial fuel inspections. An extensive effort is initiated at this time to characterize the fuel in a standard format as identified in the Appendix A attachment to the contract. The Appendix A must be finalized in an accurate and timely manner because it serves as the base reference document for WSRC and other involved stakeholders such as the cask owners and the competent authorities throughout the approval process. With the approval of the Appendix A, criticality safety reviews are initiated to evaluate the unloading and storage configurations. Operational reviews are conducted to allow for necessary adaptation of fuel handling facilities, procedures, and training. WSRC has proceduralized this process, 'Certification to Receive and

  7. Sodium hypophosphite radiographic process using an ammoniacal nickel developer

    International Nuclear Information System (INIS)

    Struckmeyer, R.K.

    1976-01-01

    Experiments were performed to determine the effect of four factors on the yield of nickel from samples of sodium hypophosphite which were exposed to 60 Co gamma radiation and then treated to an ammoniacal nickel chloride developer. The factors included sample mass, radiation exposure, development time, and concentration of NiCl 2 in the developer. Optimum normalized yields were obtained with a sample mass of 0.5 g, an exposure of 1.2 x 10 6 rad, and a development time of 8 h. The yield of Ni was observed to increase linearly with developer concentration. Attempts to prepare radiographic emulsions containing sodium hypophosphite met with limited success as only ethyl cellulose proved successful, and even these exhibited reduced sharpness of the image after only one or two days of storage

  8. Preparation, surface characterization and performance of a Fischer-Tropsch catalyst of cobalt supported on silica nanosprings

    International Nuclear Information System (INIS)

    Kengne, Blaise-Alexis Fouetio; Alayat, Abdulbaset M.; Luo, Guanqun; McDonald, Armando G.; Brown, Justin; Smotherman, Hayden; McIlroy, David N.

    2015-01-01

    Graphical abstract: - Highlights: • Determined that the reduction of Co nanoparticles on silica nanosprings 200 °C higher than the reduction temperature of Co in a solgel support. • The high reduction temperature of Co supported on silica nanosprings is attributed to the heat transfer properties of the nanosprings due to their high surface area. Co-silica nanospring Fischer-Tropsch catalyst can be used to produce drop in fuels such as JP-4. - Abstract: The reduction of cobalt (Co) catalyst supported on silica nanosprings for Fischer-Tropsch synthesis (FTS) has been monitored by X-ray photoelectron spectroscopy (XPS) and compared to FT catalytic activity. The cobalt is present in the starting catalyst as a Co 3 O 4 spinel phase. A two-step reduction of Co 3 O 4 to CoO and then to Co 0 is observed, which is consistent with the results of H 2 -temperature programmed reduction. During the reduction the two steps occur concurrently. The deconvolution of the Co 2p core level state for the catalyst reduced at 385 °C and 1.0 × 10 −6 Torr of H 2 revealed signatures of Co 0 , CoO, and Co 3 O 4 . The reduction saturates at a Co o concentration of approximately 41% after 20 h, which correlates with the activity and lifetime of the catalyst during FTS testing. Conversely, at 680 °C and 10 Torr of H 2 , the catalyst is completely reduced after 10 h. The evolution of the Co d-band at the Fermi level in the valence band XPS spectrum definitively verifies the metallic phase of Co. FTS evaluation of the Co/NS catalyst reduced at 609 °C showed higher production rate (3-fold) of C 6 -C 17 hydrocarbons than the catalyst reduced at 409 °C and is consistent with the XPS analysis.

  9. Supported liquid membrane battery separators

    Science.gov (United States)

    Pemsler, J. P.; Dempsey, M. D.

    1984-07-01

    The feasibility of using a supported liquid membrane (SLM) as a separator in the nickel-zinc battery was investigated. In particular, SLM separators should prevent zinc dendirte growth from shorting out the cell and might also alleviate capacity loss due to zinc electrode shape changes. A number of ion exchange/solvent modifier systems for incorporation into SLMs were developed under a previous LBL contract. SLMs prepared with hese reagents exhibited resistances in the range of 0.4 to 10 ohm sq cm, selectivity transported hydroxyl ions over zincate ions by a factor of 10 to the 6th power to 10 to the 7th power, and possessed electrochemical and chemical stability in alkaline electrolytes. In order to evaluate these SLM separators under conditions closely resembling a commercial Ni-Zn cell, an accelerated cycle life test was devised using commercial electrodes.

  10. Derivation of an oral toxicity reference value for nickel.

    Science.gov (United States)

    Haber, Lynne T; Bates, Hudson K; Allen, Bruce C; Vincent, Melissa J; Oller, Adriana R

    2017-06-15

    Nickel (Ni) is in the earth's crust and can be found in environmental compartments such as water, soil, and air, as well as food. This paper presents an assessment of the oral nickel toxicity data in support of non-cancer health-based oral exposure limits or toxicity reference values (TRVs). This paper derives TRVs for three populations of interest: adults, toddlers, and people who have been dermally sensitized to nickel. The adult/lifetime TRV of 20 μg Ni/kg-day is based on post-implantation loss/perinatal mortality in a 2-generation reproductive study in rats. Several recent assessments by regulatory agencies have used the same study and endpoint, but the dose-response modeling conducted here was more appropriate for the study design. Toxicokinetic data from rats and humans indicate that the applied uncertainty factors are very conservative. Because the endpoint relates to fetal exposure and is not relevant to toddlers, a toddler TRV was derived based on decreased body weight in young rats; this TRV was also 20 μg Ni/kg-day. A separate TRV of 4 μg Ni/kg in addition to Ni in food was derived for protection of nickel-sensitized populations from flare-up of dermatitis, based on studies of single exposures in humans under conditions that maximize oral absorption. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Preparation Effects on the Performance of Silica-Doped Hydrous Titanium Oxide (HTO:Si)-Supported Pt Catalysts for Lean-Burn NOx Reduction by Hydrocarbons; TOPICAL

    International Nuclear Information System (INIS)

    GARDNER, TIMOTHY J.; MCLAUGHLIN, LINDA I.; MOWERY, DEBORAH L.; SANDOVAL, RONALD S.

    2002-01-01

    This report describes the development of bulk hydrous titanium oxide (HTO)- and silica-doped hydrous titanium oxide (HTO:Si)-supported Pt catalysts for lean-burn NOx catalyst applications. The effects of various preparation methods, including both anion and cation exchange, and specifically the effect of Na content on the performance of Pt/HTO:Si catalysts, were evaluated. Pt/HTO:Si catalysts with low Na content ( and lt; 0.5 wt.%) were found to be very active for NOx reduction in simulated lean-burn exhaust environments utilizing propylene as the major reductant species. The activity and performance of these low Na Pt/HTO:Si catalysts were comparable to supported Pt catalysts prepared using conventional oxide or zeolite supports. In ramp down temperature profile test conditions, Pt/HTO:Si catalysts with Na contents in the range of 3-5 wt.% showed a wide temperature window of appreciable NOx conversion relative to low Na Pt/HTO:Si catalysts. Full reactant species analysis using both ramp up and isothermal test conditions with the high Na Pt/HTO:Si catalysts, as well as diffuse reflectance FTIR studies, showed that this phenomenon was related to transient NOx storage effects associated with NaNO(sub 2)/NaNO(sub 3) formation. These nitrite/nitrate species were found to decompose and release NOx at temperatures above 300 C in the reaction environment (ramp up profile). A separate NOx uptake experiment at 275 C in NO/N(sub 2)/O(sub 2) showed that the Na phase was inefficiently utilized for NOx storage. Steady state tests showed that the effect of increased Na content was to delay NOx light-off and to decrease the maximum NOx conversion. Similar results were observed for high K Pt/HTO:Si catalysts, and the effects of high alkali content were found to be independent of the sample preparation technique. Catalyst characterization (BET surface area, H(sub 2) chemisorption, and transmission electron microscopy) was performed to elucidate differences between the HTO- and HTO:Si-supported

  12. Preparation of magnetic silica nanoparticle-supported iron tetra-carboxyl phthalocyanine catalyst and its photocatalytic properties.

    Science.gov (United States)

    Chen, Xiaolan; Zou, Jianli; Liu, Lihua; Zhang, Yong; Huang, Jiao

    2010-05-01

    Iron tetra-carboxyl phthalocyanine (TCFePc) was covalently immobilized to the surface of core-shell magnetite silica nanoparticles (NPs) as facilely separated supported catalyst, namely P-M SiO(2) NPs, for catalyzing the degradation of organic pollutants in aqueous solution under visible light irradiation. X-ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), superconducting quantum interference device (SQUID), and ultraviolet-visible (UV-Vis) spectroscopy were used to characterize the sample. The photocatalytic activity of P-M SiO(2) NPs was determined using rhodamine B (RhB) and methyl orange (MO) as the objective decomposition substances. The results revealed that the novel supported catalyst exhibited good catalytic activity over a wide pH range, and the degradation rate of RhB and MO is up to 90% during 120 min of reaction. Moreover, it is noteworthy that the catalyst can be easily separated using an external magnetic field and employed directly for the next round of reaction.

  13. Addressing culture and context in humanitarian response: preparing desk reviews to inform mental health and psychosocial support.

    Science.gov (United States)

    Greene, M Claire; Jordans, Mark J D; Kohrt, Brandon A; Ventevogel, Peter; Kirmayer, Laurence J; Hassan, Ghayda; Chiumento, Anna; van Ommeren, Mark; Tol, Wietse A

    2017-01-01

    Delivery of effective mental health and psychosocial support programs requires knowledge of existing health systems and socio-cultural context. To respond rapidly to humanitarian emergencies, international organizations often seek to design programs according to international guidelines and mobilize external human resources to manage and deliver programs. Familiarizing international humanitarian practitioners with local culture and contextualizing programs is essential to minimize risk of harm, maximize benefit, and optimize efficient use of resources. Timely literature reviews on traditional health practices, cultural beliefs and attitudes toward mental health and illness, local health care systems and previous experiences with humanitarian interventions can provide international practitioners with crucial background information to improve their capacity to work efficiently and with maximum benefit. In this paper, we draw on experience implementing desk review guidance from the World Health Organization (WHO) and UNHCR, the United Nations Refugee Agency (2012) in four diverse humanitarian crises (earthquakes in Haiti and Nepal; forced displacement among Syrians and Congolese). We discuss critical parameters for the design and implementation of desk reviews, and discuss current challenges and future directions to improve mental health care and psychosocial support in humanitarian emergencies.

  14. Is there a link between nickel allergy and coronary stent restenosis?

    Science.gov (United States)

    Norgaz, Tugrul; Hobikoglu, Gultekin; Serdar, Zehra Asiran; Aksu, Huseyin; Alper, Ahmet Taha; Ozer, Orhan; Narin, Ahmet

    2005-07-01

    Although many patients with coronary artery disease are being treated by coronary stents, in-stent restenosis is the major limitation of percutaneous coronary stenting procedures. Most stents are made of stainless steel, and that, allergic reactions to nickel ions released from coronary stainless-steel stents may be one of the triggering mechanisms for in-stent restenosis. We aimed to evaluate the relationship between in-stent restenosis and nickel allergy in a prospective study. For this purpose, we applied epicutaneous patch test for nickel in 43 patients who had undergone elective intracoronary stent placement for stable angina pectoris in the day following stent placement and evaluated the presence of nickel allergy. Control angiography was performed at 6 months to determine in-stent restenosis. Three (6.9%) patients had allergic reaction to nickel and 16 (37%) patients had developed in-stent restenosis. One of the 3 patients with nickel allergy had diffuse in-stent restenosis and the others not. The present study therefore does not support the proposed relationship between nickel allergy and development of in-stent restenosis in patients having stainless steel stents. Large scale studies are needed to reach a final conclusion.

  15. Nickel Inhibits Mitochondrial Fatty Acid Oxidation

    Science.gov (United States)

    Uppala, Radha; McKinney, Richard W.; Brant, Kelly A.; Fabisiak, James P.; Goetzman, Eric S.

    2015-01-01

    Nickel exposure is associated with changes in cellular energy metabolism which may contribute to its carcinogenic properties. Here, we demonstrate that nickel strongly represses mitochondrial fatty acid oxidation—the pathway by which fatty acids are catabolized for energy—in both primary human lung fibroblasts and mouse embryonic fibroblasts. At the concentrations used, nickel suppresses fatty acid oxidation without globally suppressing mitochondrial function as evidenced by increased glucose oxidation to CO2. Pre-treatment with L-carnitine, previously shown to prevent nickel-induced mitochondrial dysfunction in neuroblastoma cells, did not prevent the inhibition of fatty acid oxidation. The effect of nickel on fatty acid oxidation occurred only with prolonged exposure (>5 hr), suggesting that direct inhibition of the active sites of metabolic enzymes is not the mechanism of action. Nickel is a known hypoxia-mimetic that activates hypoxia inducible factor-1α (HIF1α). Nickel-induced inhibition of fatty acid oxidation was blunted in HIF1α knockout fibroblasts, implicating HIF1α as one contributor to the mechanism. Additionally, nickel down-regulated the protein levels of the key fatty acid oxidation enzyme very long-chain acyl-CoA dehydrogenase (VLCAD) in a dose-dependent fashion. In conclusion, inhibition of fatty acid oxidation by nickel, concurrent with increased glucose metabolism, represents a form of metabolic reprogramming that may contribute to nickel-induced carcinogenesis. PMID:26051273

  16. Gold, nickel and copper mining and processing.

    Science.gov (United States)

    Lightfoot, Nancy E; Pacey, Michael A; Darling, Shelley

    2010-01-01

    Ore mining occurs in all Canadian provinces and territories except Prince Edward Island. Ores include bauxite, copper, gold, iron, lead and zinc. Workers in metal mining and processing are exposed, not only to the metal of interest, but also to various other substances prevalent in the industry, such as diesel emissions, oil mists, blasting agents, silica, radon, and arsenic. This chapter examines cancer risk related to the mining of gold, nickel and copper. The human carcinogenicity of nickel depends upon the species of nickel, its concentration and the route of exposure. Exposure to nickel or nickel compounds via routes other than inhalation has not been shown to increase cancer risk in humans. As such, cancer sites of concern include the lung, and the nasal sinus. Evidence comes from studies of nickel refinery and leaching, calcining, and sintering workers in the early half of the 20th century. There appears to be little or no detectable risk in most sectors of the nickel industry at current exposure levels. The general population risk from the extremely small concentrations detectable in ambient air are negligible. Nevertheless, animal carcinogenesis studies, studies of nickel carcinogenesis mechanisms, and epidemiological studies with quantitative exposure assessment of various nickel species would enhance our understanding of human health risks associated with nickel. Definitive conclusions linking cancer to exposures in gold and copper mining and processing are not possible at this time. The available results appear to demand additional study of a variety of potential occupational and non-occupational risk factors.

  17. Preparation, surface characterization and performance of a Fischer-Tropsch catalyst of cobalt supported on silica nanosprings

    Energy Technology Data Exchange (ETDEWEB)

    Kengne, Blaise-Alexis Fouetio [Department of Physics, University of Idaho, Moscow, ID 83844-0903 (United States); Alayat, Abdulbaset M. [Environmental Science Program, University of Idaho, Moscow, ID 83844-3006 (United States); Luo, Guanqun [Department of Forest, Rangeland & Fire Sciences, University of Idaho, Moscow, ID 83844-1132 (United States); McDonald, Armando G. [Environmental Science Program, University of Idaho, Moscow, ID 83844-3006 (United States); Department of Forest, Rangeland & Fire Sciences, University of Idaho, Moscow, ID 83844-1132 (United States); Brown, Justin; Smotherman, Hayden [Department of Physics, University of Idaho, Moscow, ID 83844-0903 (United States); McIlroy, David N., E-mail: dmcilroy@uidaho.edu [Department of Physics, University of Idaho, Moscow, ID 83844-0903 (United States)

    2015-12-30

    Graphical abstract: - Highlights: • Determined that the reduction of Co nanoparticles on silica nanosprings 200 °C higher than the reduction temperature of Co in a solgel support. • The high reduction temperature of Co supported on silica nanosprings is attributed to the heat transfer properties of the nanosprings due to their high surface area. Co-silica nanospring Fischer-Tropsch catalyst can be used to produce drop in fuels such as JP-4. - Abstract: The reduction of cobalt (Co) catalyst supported on silica nanosprings for Fischer-Tropsch synthesis (FTS) has been monitored by X-ray photoelectron spectroscopy (XPS) and compared to FT catalytic activity. The cobalt is present in the starting catalyst as a Co{sub 3}O{sub 4} spinel phase. A two-step reduction of Co{sub 3}O{sub 4} to CoO and then to Co{sup 0} is observed, which is consistent with the results of H{sub 2}-temperature programmed reduction. During the reduction the two steps occur concurrently. The deconvolution of the Co 2p core level state for the catalyst reduced at 385 °C and 1.0 × 10{sup −6} Torr of H{sub 2} revealed signatures of Co{sup 0}, CoO, and Co{sub 3}O{sub 4}. The reduction saturates at a Co{sup o} concentration of approximately 41% after 20 h, which correlates with the activity and lifetime of the catalyst during FTS testing. Conversely, at 680 °C and 10 Torr of H{sub 2}, the catalyst is completely reduced after 10 h. The evolution of the Co d-band at the Fermi level in the valence band XPS spectrum definitively verifies the metallic phase of Co. FTS evaluation of the Co/NS catalyst reduced at 609 °C showed higher production rate (3-fold) of C{sub 6}-C{sub 17} hydrocarbons than the catalyst reduced at 409 °C and is consistent with the XPS analysis.

  18. A Highly Sensitive Electrochemical Glucose Sensor By Nickel-Epoxy Electrode With Non-Enzymatic Sensor

    Directory of Open Access Journals (Sweden)

    Riyanto Riyanto

    2016-03-01

    Full Text Available The preparation of new sensor for glucose was based on the fact that glucose can be determined by non-enzymatic glucose oxidase. The Ni metals (99.98% purity, 0.5 mm thick, Aldrich Chemical Company was used to prepare Ni-Epoxy electrode. The Ni-epoxy electrodes were prepared in square cut of 1 cm and 1 mm by length and wide respectively. The Ni metal electrodes were connected to silver wire with silver conducting paint prior covered with epoxy gum. The prepared of nickel-epoxy modified electrode showed outstanding electro catalytic activity toward the oxidation of glucose in alkaline solution. The result from this research are correlation of determination using Nickel-Epoxyelectrode for electroanalysis of glucose in NaOH was R2 = 0.9984. LOQ, LOD and recovery of the Nickel-Epoxy electrode towards glucose were found to be 4.4 μM, 1.48 μM and 98.19%, respectively. The Nickel-Epoxy wire based electrochemical glucose sensor demonstrates good sensitivity, wide linear range, outstanding detection limit, attractive selectivity, good reproducibility, high stability as well as prominent feasibility use of non-enzymatic sensor for monitoring glucose in human urine owing to its advantages of low cost, simple preparation and excellent properties for glucose detection.

  19. PREPARATION OF SPENT BLEACHING EARTH-SUPPORTED CALCIUM FROM LIMESTONE AS CATALYST IN TRANSESTERIFICATION OF WASTE FRYING OIL

    Directory of Open Access Journals (Sweden)

    Noor Hindryawati

    2017-06-01

    Full Text Available An investigation was conducted on palm oil refinery waste-spent bleaching earth (POR-SBE, POR-SBE supported by calcium as catalysts for methyl esters production through transesterification process using waste frying oil. The catalysts showed longer lasting activity than the traditional alkali catalysts. The optimum conditions for the process were: Ca-POR-SBE catalyst amount 7 %; methanol to oil molar ratio 12:1; and a reaction duration is 4 h. The process was able to transesterify oil to methyl esters at 96.8 % conversion at 65 °C. The catalysts were easily separated from the reaction mixture and the final product met selected biodiesel fuel properties in accordance with European Standard EN 14214.

  20. Preparation of 3D nanoporous copper-supported cuprous oxide for high-performance lithium ion battery anodes.

    Science.gov (United States)

    Liu, Dequan; Yang, Zhibo; Wang, Peng; Li, Fei; Wang, Desheng; He, Deyan

    2013-03-07

    Three-dimensional (3D) nanoporous architectures can provide efficient and rapid pathways for Li-ion and electron transport as well as short solid-state diffusion lengths in lithium ion batteries (LIBs). In this work, 3D nanoporous copper-supported cuprous oxide was successfully fabricated by low-cost selective etching of an electron-beam melted Cu(50)Al(50) alloy and subsequent in situ thermal oxidation. The architecture was used as an anode in lithium ion batteries. In the first cycle, the sample delivered an extremely high lithium storage capacity of about 2.35 mA h cm(-2). A high reversible capacity of 1.45 mA h cm(-2) was achieved after 120 cycles. This work develops a promising approach to building reliable 3D nanostructured electrodes for high-performance lithium ion batteries.