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Articles 25771 - 25800 of 34747

Full-Text Articles in Physical Sciences and Mathematics

Isotopes Tell Sun's Origin And Operation, Oliver Manuel, Sumeet A. Kamat, Michael Mozina Jun 2006

Isotopes Tell Sun's Origin And Operation, Oliver Manuel, Sumeet A. Kamat, Michael Mozina

Chemistry Faculty Research & Creative Works

Modern versions of Aston's mass spectrometer enable measurements of two quantities - isotope abundances and masses - that tell the Sun's origin and operation. Isotope analyses of meteorites, the Earth, Moon, Mars, Jupiter, the solar wind, and solar flares over the past 45 years indicate that fresh, poorly-mixed, supernova debris formed the solar system. The iron-rich Sun formed on the collapsed supernova core and now itself acts as a magnetic plasma diffuser, as did the precursor star, separating ions by mass. This process covers the solar surface with lightweight elements and with the lighter isotopes of each element. Running difference …

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Molecular Characterization Of Wetland Soil Bacterial Community In Constructed Mesocosms, Ethan C. Bishop Jun 2006

Molecular Characterization Of Wetland Soil Bacterial Community In Constructed Mesocosms, Ethan C. Bishop

Theses and Dissertations

The use of wetlands to effectively remediate aquifers contaminated with chlorinated solvents is an emerging technique, which shows high promise. In order to better understand this process and test its legitimacy, a treatment wetland was constructed at Wright-Patterson AFB, Dayton, Ohio and, in a joint effort with Wright State University (WSU), has previously shown the effective removal of PCE. The purpose of this research was to characterize the soil bacterial community, pre-PCE injection, among three wetland plant species from the sedge family (Cyperaceae) within constructed wetland mesocosms and to identify any bacterial dominance. Carex comosa, Scirpus atrovirens, and Eleocharis erythropoda …

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Studies Toward The Enantioselective Total Synthesis Of The Martinella Alkaloids, Vivek Badarinarayana Jun 2006

Studies Toward The Enantioselective Total Synthesis Of The Martinella Alkaloids, Vivek Badarinarayana

Chemistry & Biochemistry Dissertations

This dissertation consists of two parts. The first part describes the enantioselective total synthesis of martinellic acid. The Martinella alkaloids have attracted considerable attention in the synthetic community over the past few years. This interest is due in large part to their unique structure and useful biological activity (bradykinin receptor antagonist). In model systems we have successfully used the [3+2] azomethine ylide-alkene cycloaddition to construct the heterocyclic core of these alkaloids. The enantioselective approach described herein also involves the azomethine ylide-alkene cycloaddition as a key step in the total synthesis. The pyrrolo[3,2-c]quinoline core of this alkaloid was constructed in an …

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Gas Chromatography On Self Assembled Single Walled Carbon Nanotubes, Mahesh Kumar Karwa May 2006

Gas Chromatography On Self Assembled Single Walled Carbon Nanotubes, Mahesh Kumar Karwa

Dissertations

Carbon nanotubes (CNTs) are nano-sized carbon-based sorbents, which have high surface area, large aspect ratio, can be self-assembled and are known to be stable at high temperatures. It is therefore conceivable that separation techniques, such as, gas chromatography (GC) can benefit from their unique properties and nano-scale interactions. Self-assembly, in-contrast to packing these materials in a tube, prevents them from agglomeration and thus facilitates in retaining their nano-characteristics. In this research, novel substrates, such as, steel tubings, on a scaled-up level have been explored for the self-assembly process of CNTs, for applications such as gas chromatography, where the CNTs served …

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Evidence Of Hollow Golden Cages, Satya S. Bulusu, Xi Li, Lai-Sheng Wang, Xiao Cheng Zeng May 2006

Evidence Of Hollow Golden Cages, Satya S. Bulusu, Xi Li, Lai-Sheng Wang, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

The fullerenes are the first “free-standing” elemental hollow cages identified by spectroscopy experiments and synthesized in the bulk. Here, we report experimental and theoretical evidence of hollow cages consisting of pure metal atoms, Au–n (n = 16–18); to our knowledge, free-standing metal hollow cages have not been previously detected in the laboratory. These hollow golden cages (“bucky gold”) have an average diameter >5.5 Å, which can easily accommodate one guest atom inside.

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Evidence Of Hollow Golden Cages: Supplementary Materials And Supporting Information, Satya S. Bulusu, Xi Li, Lai-Sheng Wang, Xiao Cheng Zeng May 2006

Evidence Of Hollow Golden Cages: Supplementary Materials And Supporting Information, Satya S. Bulusu, Xi Li, Lai-Sheng Wang, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

Figures 3A-3D: Simulated anion photoelectron spectra [based on the density-functional theory (DFT) calculation with the PBEPBE/LANL2DZ functional and basis set] for all of the candidate lowest-energy isomers of
Au¯15 (A),
Au¯16 (B),
Au¯17 (C), and
Au¯18 (D) identified in Fig. 3 A–D, respectively.

Figures 4A-4E: Top-10 lowest-energy isomers of Au¯15, Au¯16, Au¯17, Au¯18, and Au¯19 obtained from a basin-hopping global search combined with DFT optimization and total-energy calculation.

Table 2: The experimental adiabatic detachment energies (ADEs) for Au¯n (n = 15–19) measured from the threshold …

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The Ultraviolet Spectrum Of The Cocl2 Radical, Studied At Vibrational And Rotational Resolution, Thomas Varberg, Philip J. Hodges, John M. Brown May 2006

The Ultraviolet Spectrum Of The Cocl2 Radical, Studied At Vibrational And Rotational Resolution, Thomas Varberg, Philip J. Hodges, John M. Brown

Thomas D. Varberg

No abstract provided.

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Corrosion Behavior Of The Welding Seam Of The Q235 Steel Jointed By J420 Electrode In Ammonium Sulfite Solution, A-Li Lei, Qiao-Qin Guo, La-Jun Feng May 2006

Corrosion Behavior Of The Welding Seam Of The Q235 Steel Jointed By J420 Electrode In Ammonium Sulfite Solution, A-Li Lei, Qiao-Qin Guo, La-Jun Feng

Journal of Electrochemistry

The corrosion behavior of welding seam of the Q235 steel jointed by J420 electrode in ammonium sulfite solution was researched.The results of electrochemical method of welding seam and metallurgical structure analysis showed that the poor corrosion resisting property was determined by its structure after the Q235 steel was jointed by J420 electrode.The sulfite corrosion rate was accelerated by increasing the temperature and concentration of ammorium.

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Application Of Electrolessplating Technology In Interconnection Manufacturing Of Ultralarge-Scale Integration, Zeng-Lin Wang May 2006

Application Of Electrolessplating Technology In Interconnection Manufacturing Of Ultralarge-Scale Integration, Zeng-Lin Wang

Journal of Electrochemistry

In this paper,research progresses in electroless plating for damascene copper process were reviewed.Electroless nickel ternary alloy deposition for barrier layer and electroless copper plating for seed layer were presented.Bottom-up copper fill high-aspect-via-hole and electroless plating after ICB-Pd catalytic layer for seed layer were mainly introduced.The applications of electroless plating in ultralarge-scale integration were discussed,and the developing tendency was also suggested.

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Synthesis Of Zinc Polyhedral Microspheres And Applications In Alkaline Zn-Mno_(2)Battery, Hua Ma, Chun-Sheng Li, Fang-Yi Cheng, Chun-Yuan Zhou, Feng Gao, Jun Chen May 2006

Synthesis Of Zinc Polyhedral Microspheres And Applications In Alkaline Zn-Mno_(2)Battery, Hua Ma, Chun-Sheng Li, Fang-Yi Cheng, Chun-Yuan Zhou, Feng Gao, Jun Chen

Journal of Electrochemistry

The zinc polyhedral microspheres were synthesized by evaporation of pure zinc powders via a vapor-transport process.The results characterized by XRD and SEM show that the as-synthesized zinc powders are polyhedral microspheres with the diameter of 2~3 μm.The electrochemical investigation showed that the capacity of the as-assembled AA-size primary alkaline Zn-MnO_(2)battery was increased to 3.14 Ah under the constant discharge current of 100 mA by using the as-deposited microspherical zinc powders as the anode active materials and γ-MnO_(2)nanowires as the cathode active materials,indicating their potential application in high-energy batteries.

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Investigation On Ru-Ti-Ir Anode Coatings Modified By Adding Sn Element, Wang Ke May 2006

Investigation On Ru-Ti-Ir Anode Coatings Modified By Adding Sn Element, Wang Ke

Journal of Electrochemistry

The anode coatings of Ru-Ti-Ir-Sn oxide with various Sn contents were prepared by thermal decomposition and characterized by the scanning electron microscopy(SEM),energy dispersive X-ray detector(EDX),X-ray diffraction(XRD),and the potential of chlorine evolution,current efficiency,cyclic voltammetry and electrochemical impedance spectroscopy(EIS).The results tests showed that there was a great change in the morphology of the coatings after adding Sn element.The addition of Sn not only reduced the potential of chlorine evolution,but also effectively improved the current efficiency of the anode coatings.

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Compare Of The Behavior Of Different Sloth Filler Bipolar Packed Bed Cell In The Treatment Of Sodium P-Nitro-Phenolate, Shi-Yuan Guo, Ai-Li Zhang, Ji-Ti Zhou May 2006

Compare Of The Behavior Of Different Sloth Filler Bipolar Packed Bed Cell In The Treatment Of Sodium P-Nitro-Phenolate, Shi-Yuan Guo, Ai-Li Zhang, Ji-Ti Zhou

Journal of Electrochemistry

Making use of sulphonated coal,fruit hull,plastic of PVC,old plastic in recovery,four kinds of sloth fillers which densities are equal to active carbon to substitute quartz sand which are applied in project extensively.And link with appropriate backwashing to resolve the problem of electrodes pollution and &lamination of the fillers in the bipolar packed bed cell.Then via the treatment of the waste water that contains sodium p-ni-tro-phenolate to investigate the possibility of application.The results are as follow.There are better resuk for the reactors packed with old plastics in recovery and sulphonated coal than the one filled with quartz sand,and the results of …

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Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang May 2006

Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang

Journal of Electrochemistry

The Sn-Co alloy deposits were prepared by electroplating.The structure and electrochemical performance of the electroplated Sn-Co alloys have been investigated in detail.Experimental results show that the porous Sn-Co alloy film exhibits hexagonal solid solution,with Sn as the solvent, Co as the solute.The texture of the Sn-Co alloy coating exhibits(110) preferred orientation.Electrochemical tests show that the porous Sn-Co alloy coating electrodes can deliver a discharge capacity of 643mAh/g in the first cycle.At the 20~(h) cycle the charge was 461mAh/g.At initial charge curve the irreversible capacity is probably associated to a combination of processes,which may include the reduction of small amount of …

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Effect Of Cracks On Corrosion Of Rebar In Concrete Studied By Wire Beam Electrode, Guo-Xi Li May 2006

Effect Of Cracks On Corrosion Of Rebar In Concrete Studied By Wire Beam Electrode, Guo-Xi Li

Journal of Electrochemistry

The effects of crack and ethanolamine on corrosion of rebar in concrete were studied by measuring the distribution of corrosion potential and polarization resistance of iron wires in 10% NaCl solution.The results showed that the diffusion of water,oxygen and chloric ion toward concrete was accelerated by the crack which intensified the nonuniform corrosion of iron wire with the regions near to crack as anode and the uncracked regions as cathode.Ethanolamine could diffuse into the body of concrete and absorb on the surface of iron wire,which reduced iron corrosion evidently and successfully inhibited the nonuniform corrosion caused by crack without changing …

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Electrochemical Preparation Of Gd-Ni Alloy Film In Acetamide-Urea-Nabr Melt, Bi-Qing Chen, Jian-Chao Wang, Chen-Yu Guo, Jin-Gui Wang, Qing Liu May 2006

Electrochemical Preparation Of Gd-Ni Alloy Film In Acetamide-Urea-Nabr Melt, Bi-Qing Chen, Jian-Chao Wang, Chen-Yu Guo, Jin-Gui Wang, Qing Liu

Journal of Electrochemistry

Cyclic voltammetry was used to study the electroreduction of Ni~(2+)to Ni on Pt and Cu electrode in acetamide-urea-NaBr melt at 353K.It is irreversible in one step.At Pt and Cu eletrode the diffusion coefficient and electron transfer coefficient of Ni~(2+) in 0.063mol/dm~(3) NiCl_(2)-acetamide-urea-NaBr melt were determined.The transfer coefficient α=0.28 and diffusion coefficient D_(0)=4.63×10~(-5) cm~(2·)s~(-1)of the Pt eletrode and transfer coefficient α=0.22 and diffusion coefficient D_(0)=6.05×10~(-7) cm~(2·)s~(-1)of the Cu eletrode were measured.It was put emphasis on that Gd~(3+) is not reduced to Gd alone in copper matrix,but can be inductively codeposited with Ni~(2+).The amorphous Gd-Ni alloy films were obtained by potentiostatic electrolysis.The …

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Study On Composite Organic Inhibitor Of Zinc Electrode In Alkaline Solutions, Xue-Tao Bu, Guang-Chuan Liang, Cui Li May 2006

Study On Composite Organic Inhibitor Of Zinc Electrode In Alkaline Solutions, Xue-Tao Bu, Guang-Chuan Liang, Cui Li

Journal of Electrochemistry

The synergetic influence of sodium dodecyl benzene sulfonate(SDBS) with Tween-20(Tween) on zinc electrode was studied by polarization experiment,surface tension test,discharge test and SEM.It is found that the composite inhibitor ST has a much higher efficiency.The addition of Tween reduced the critical micell concentration of SDBS on zinc electrode remarkably and the distribution of adsorption became more homogeneous.ST inhibits corrosion of zinc electrode and improves discharge capacity of the whole battery.Through electrochemical morphological observation of anodic passivation behaviors of zinc electrode,the absorption of ST on electrode surface makes discharged production much smaller and keeps crude porous structure intact.Passivation of zinc electrode …

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Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang May 2006

Electrochemical Preparation And Application Of Nanomaterials, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang

Journal of Electrochemistry

Nano materials and nano technology receive great attention all over the world.While electrochemistry has already achieved a great application in industry and it has proved that electrochemistry will play an important role in the field,such as energy source,new materials,life sciences,information sciences,environment and nano sciences.In this paper,the recent developments of electrochemical techniques for the preparing nano materials,application of nano materials in the areas of electrodeposition,batteries,electrocatalysis,sensors are introduced in brief.

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An Electro-Driving High Efficiency,Continuous,No-Damage Focusing Electrophoresis Concentration Device, Hua-Shui Lin, Liang-Ge Chen, Run-Xiang Zhang, Fan Luo, Wei-Ling Hu, Zhao-Wu Tian May 2006

An Electro-Driving High Efficiency,Continuous,No-Damage Focusing Electrophoresis Concentration Device, Hua-Shui Lin, Liang-Ge Chen, Run-Xiang Zhang, Fan Luo, Wei-Ling Hu, Zhao-Wu Tian

Journal of Electrochemistry

We presented a membrane focusing concentration method and fabricatedan electro-driving high efficiency,continuous,no-damage focusing electrophoresis concentration device.In the concentration experiments of bromophenol blue and Na-fluorescein,the concentrated efficiencyof the device reached two orders of magnitude.This device can be magnified to industrial equipment with large output.It also can be miniaturized to small and simple attachment for separated and analytical instrument such as electrophoresis,chromatogram, mass spectrum and optical spectrum.When integrated into chips,it would be a pre-concentrated unit of the lab-on-chip.

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An Electrochemical Investigation Of Methanol Crossover In Dmfcs, Meng-Di You, Xuan Cheng, Liulian Liulian, Zhang Lu May 2006

An Electrochemical Investigation Of Methanol Crossover In Dmfcs, Meng-Di You, Xuan Cheng, Liulian Liulian, Zhang Lu

Journal of Electrochemistry

Methanol crossover and its effect on the open-circuit voltage(OCV) in DMFCs were studied usingcyclic voltammetry and chronoamperometry under stationary condition and at ambient temperature.An H-shapecell was constructed and a simulative DMFC test was carried out to investigate methanol crossover through Na-fion(117 from anode to cathode.The results revealed thatthe amountof methanol in the cathode side is depend-ent upon the time of penetration.As the concentration of methanol increased,the hydrogen adsorption-desorptionon the surface of electrode was suppressed and a shoulder peak appeared during the forward sweep for methanoloxidation.The simulative DMFC test also showed that the methanol crossover caused a sudden decline in theOCV.

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Electrochemical Studies Of Iron-Doped Nickel Oxide Electrode For Oxygen Evolution Reaction, Jin-Zhao Huang, Zheng Xu, Hai-Ling Li, Guo-Hu Kang, Wen-Jing Wang May 2006

Electrochemical Studies Of Iron-Doped Nickel Oxide Electrode For Oxygen Evolution Reaction, Jin-Zhao Huang, Zheng Xu, Hai-Ling Li, Guo-Hu Kang, Wen-Jing Wang

Journal of Electrochemistry

In this paper,the iron-doped nickel oxide thin film as anode catalyst was prepared by RF reactivesputtering method.The oxygen evolution reaction(OER) on the iron-doped nickel oxide was investigated withcyclic voltammetry,liner sweep voltammetry,polarization curves and electrochemical impedance spectroscopy.Results showthat the iron acts as active site in the film which makes the overpotential lower,and changes therate-limiting from primary discharge of OH-ions to the recombination of oxygen atom.With the increasing of ox-ygen content in flu ratio during sputtering,the electrocatalytic activities of the film increase.Iron-doped nickeloxide thin film is promising material as OER electrocatalyst for hydrogen production than the nickel electrode.The oxygen overpotential on the …

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Electrochemical Impedance Spectrum Of Ferrocene At A Rotating Disk Glassy Carbon Electrode And Its Interaction With Dna, Can-Hui Chen May 2006

Electrochemical Impedance Spectrum Of Ferrocene At A Rotating Disk Glassy Carbon Electrode And Its Interaction With Dna, Can-Hui Chen

Journal of Electrochemistry

The electrochemical impedance spectrum(EIS) of ferrocene(Fc) at a rotating glassy carbon(GC) electrode and its interaction with calf thymus DNA in Tris-NaCl buffer solution(pH=7.2) have been investigated by using electrochemical techniques such as rotating disk electrode(RDE),EIS and its data fitting.A plateau of the limiting current for the voltammetric curve and two capacitance arches obtained at the rotating GC electrode are exhibited.The interaction of Fc with DNA is represented by the decrease of limiting diffusion current and the increase of electrochemical reaction resistances with the increase of DNA concentration,respectively.On the other hand,based on the theoretical analysis and data fitting of RDE and …

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Electrodeposition Of Three-Dimensional Porous Copper Films Using Hydrogen Bubbles As Template, Ya-Feng Sun, Zhen-Jiang Niu May 2006

Electrodeposition Of Three-Dimensional Porous Copper Films Using Hydrogen Bubbles As Template, Ya-Feng Sun, Zhen-Jiang Niu

Journal of Electrochemistry

Using cathodic hydrogen bubbles as a template,the three-dimensional(3-D) porous copper films have been successfully electrodeposited from a bath of 0.2 mol·dm~(-3) CuSO_(4) and 1.5 mol·dm~(-3) H_(2)SO_(4),effects of deposition parameters including temperature,current density and additives(Na_(2)SO_(4),HCl and Polyethylene glycol(PEG)) on the morphologies of the deposits have been systematically studied.SEM results showed that both the pore size and thickness of the pore walls decreased with cooling the electrolyte temperature or adding(Na_(2)SO_(4)) or PEG into the bath when the other deposition parameters were fixed.With addition small amounts of HCl in the bath,the wall structures of the films could be profoundly changed by refining the …

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High Density Lifepo_4/C Synthesized By Controlled Crystallization And Microwave Carbon Thermal Reduction, Chang-Ping Tang, Jie-Rong Ying, Min Lei, Wei Li, Chang-Yin Jiang, Chun-Rong Wan May 2006

High Density Lifepo_4/C Synthesized By Controlled Crystallization And Microwave Carbon Thermal Reduction, Chang-Ping Tang, Jie-Rong Ying, Min Lei, Wei Li, Chang-Yin Jiang, Chun-Rong Wan

Journal of Electrochemistry

The spherical FePO_(4)·xH_(2)O was prepared in the solution by controlled crystallization.The precursor FePO_(4)was obtained in high temperatureceramic approach,then the high density LiFePO_(4)/C was synthesized by microwave carbon thermal reduction.The structure and morphology of the materials were characterized by means of XRD and SEM techniques,and the electrochemical properties were studies by charge-discharge experiments.

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Preparation Of Spherical Ni(Oh)_2 Coated With Coooh And Its Fast Charge Performance, Min-Jie Yang May 2006

Preparation Of Spherical Ni(Oh)_2 Coated With Coooh And Its Fast Charge Performance, Min-Jie Yang

Journal of Electrochemistry

Spherical Ni(OH)_(2) was coated with CoOOH through chemical precipitation and electrolytic oxidation.The influences of CoOOH coating on fast charge performance ofMH/Ni battery were studied by preparing high capacity and fast charge AA size MH/Ni batteries.The sample coated with CoOOH was characterized by Infrared spectrum(IR) and scanning electron microscopy(SEM).The results showed that the internal resistance decreased 3.4 mΩ,the charge plateau lower and the cell temperrature was below 55 ℃ at the end of charging process when the cathode active material used Ni(OH)_2 coated with CoOOH as compared with that doped by CoO.In addition,an initial discharge efficiency of 90.6% and over 300 …

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Effect Of Preparation Conditions On Electroluminescence Of Porous Silicon, Ya-Jun Yang May 2006

Effect Of Preparation Conditions On Electroluminescence Of Porous Silicon, Ya-Jun Yang

Journal of Electrochemistry

Electrically induced visible light emitting porous silicon devices with the structure of ITO/PS/p-Si/Al were fabricated by evaporation-anodic oxidation method.The light emission last for a few hours under 7.5V forward bias conditions.It was shown that the electroluminescence(EL) peaks shifted to the blue with the increasing of current density,erosion time and solution concentration.In order to achieve samples with low driven voltage,long light emission time and high EL efficiency,porous silicon should be prepared under low current density and short erosion time.

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Tyrosinase Immobilizarion On Boron-Doped Diamond Electrodes And The Determination Of Phenolic Compounds, Yan-Li Zhou, Jin-Fang Zhi May 2006

Tyrosinase Immobilizarion On Boron-Doped Diamond Electrodes And The Determination Of Phenolic Compounds, Yan-Li Zhou, Jin-Fang Zhi

Journal of Electrochemistry

As-grown BDD surfaces were first functionalized by photochemically linking vinyl groups of allylamine,producing covalently linked amine-terminated active BDD surfaces.Then the tyrosinase was immobilized onto the BDD surface through peptide linking.Cyclic voltammograms of phenol,pcresol and hydroquinone were measured using the tyrosinase-modified BDD electrode and amperometric characteristics such as sensitivity,linear response range and stability were studied.

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Electrochemical Studies On Electrocatalytic Activity Of Au_(Core) Pt_(Shell)Nanoparticles To Methanol Oxidation, Fang Bao, Jian-Lin Yao, Ren-Ao Gu May 2006

Electrochemical Studies On Electrocatalytic Activity Of Au_(Core) Pt_(Shell)Nanoparticles To Methanol Oxidation, Fang Bao, Jian-Lin Yao, Ren-Ao Gu

Journal of Electrochemistry

Au_(core)Pt_(shell)nanoparticles with different thicknesses were prepared by using chemical reduction method,and characterized by ultraviolet-visible spectroscopy(UV-Vis),transmission electron microscopy(TEM) and cyclic voltammetry(CV).The electrocatalytic activity of Au_(core)Pt_(shell)nanoparticles with the mean diameter of 70~80 nm to methanol oxidation was investigated by cyclic voltammetry in the acid solution.The results revealed that the prepared core-shell nanoparticles were covered by Pt shell and exhibited the similar optical property and electrocatalytic activity with the normal Pt surface.Moreover,the electrocatalytic activity increased with the electrochemical sweep in the certain potential range.It might be contributed by the special loose structure of Pt shell rather than the increase of the real area.

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Effects Of Eelectrolyte Salt To The Sei Layer Of Licoo_2 Material, Ming-Sen Zheng May 2006

Effects Of Eelectrolyte Salt To The Sei Layer Of Licoo_2 Material, Ming-Sen Zheng

Journal of Electrochemistry

The character of the solid electrolyte interface(SEI layer) on the surface of LiCoO_(2) formed in the electrolytes contained different salt such as LiPF_(6)、LiClO_(4) and LiBF_(4) were studied in this paper.The results showed that the SEI film exists in all three electrolytes after the processes of charge and discharge.The morphological character and the formation voltage of the SEI layer of LiCoO_(2) were different in different electrolytes.The electrochemical performance of the battery such as reversible capacity,average discharge voltage and electrochemical impedance were affected significantly by SEI film formed in different electrolytes.

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Electrochemical Behavior And Reduction Mechanism Of High Valence Silver Oxide Ag_3o_4 In Alkaline Solution, Yan Cheng, Ming Yu, Man-Ming Yan, Zhi-Yu Jiang May 2006

Electrochemical Behavior And Reduction Mechanism Of High Valence Silver Oxide Ag_3o_4 In Alkaline Solution, Yan Cheng, Ming Yu, Man-Ming Yan, Zhi-Yu Jiang

Journal of Electrochemistry

The electrochemical properties of high-valence silver oxide Ag_(3)O_(4)in alkaline solution were investigated for the first time and the reduction mechanism of Ag_(3)O_(4) was proposed.It can be recognized that Ag_(3)O_(4)consists of_()Ag(Ⅲ) and Ag(Ⅱ)~(*).From the results of voltammetry and XRD experiments it was found that the reduction process of Ag_(3)O_(4) was more complicated.It could be electrochemically reduced through the series reactions of Ag(Ⅲ) →Ag(Ⅱ) →Ag(Ⅰ) →Ag(O) at low discharge rate or Ag(Ⅲ) →Ag(Ⅰ) →Ag(O) at higher discharge rate.And the Ag(Ⅱ)~(*) could be reduced to Ag directly at low potential region.In addition,it is interesting to note that Ag_(3)O_(4) presents the theoretical specific discharge …

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Volatile Organic Compounds Composition Of Merged And Aged Forest Fire Plumes From Alaska And Western Canada, Joost A. De Gouw, C. Warneke, A. Stohl, A. G. Wollny, C. A. Brock, O. R. Cooper, J. S. Holloway, M. Trainer, F. C. Fehsenfeld, E. L. Atlas, Stephen G. Donnelly Ph.D., V. Stroud, A. Lueb May 2006

Volatile Organic Compounds Composition Of Merged And Aged Forest Fire Plumes From Alaska And Western Canada, Joost A. De Gouw, C. Warneke, A. Stohl, A. G. Wollny, C. A. Brock, O. R. Cooper, J. S. Holloway, M. Trainer, F. C. Fehsenfeld, E. L. Atlas, Stephen G. Donnelly Ph.D., V. Stroud, A. Lueb

Chemistry Faculty Publications

The NOAA WP-3 aircraft intercepted aged forest fire plumes from Alaska and western Canada during several flights of the NEAQS-ITCT 2k4 mission in 2004. Measurements of acetonitrile (CH3CN) indicated that the air masses had been influenced by biomass burning. The locations of the plume intercepts were well described using emissions estimates and calculations with the transport model FLEXPART. The best description of the data was generally obtained when FLEXPART injected the forest fire emissions to high altitudes in the model. The observed plumes were generally drier than the surrounding air masses at the same altitude, suggesting that the fire plumes …

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