Open Access. Powered by Scholars. Published by Universities.®

Physical Chemistry Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 3931 - 3960 of 4497

Full-Text Articles in Physical Chemistry

Kinetic Study Of Electrooxidation Of Benzene, Xin-Sheng Zhang, Ping Ding, Ying-Chun Dai, Wei-Kang Yuan Feb 1999

Kinetic Study Of Electrooxidation Of Benzene, Xin-Sheng Zhang, Ping Ding, Ying-Chun Dai, Wei-Kang Yuan

Journal of Electrochemistry

A reaction kinetic study for electrochemical oxidation of benzene was performed on a PbO2 rotating disk electrode in 1 mol/L H2SO4 aqueous solution. The reaction orders, the activation energies and transfer coefficient were measured, and the kinetic expression was obtained.


Pitting Corrosion Of Ni-Based Alloy In Thiosulfate-Ion Containing Chloride Solutions, Yung-Fa Lee, Ting-Yu Wang, Wen-Ta Tsai Feb 1999

Pitting Corrosion Of Ni-Based Alloy In Thiosulfate-Ion Containing Chloride Solutions, Yung-Fa Lee, Ting-Yu Wang, Wen-Ta Tsai

Journal of Electrochemistry

The effect of thiosulfate ion on the pitting corrosion behavior of Ni-Based Alloy 690 in chloride solution was investigated. In plain sodium thiosulfate solution, Alloy 690 was immune to pitting corrosion. However, the addition of low concentration of sodium thiosulfate can enhance the initiation of pitting corrosion of Alloy 690. Nevertheless, inhibition of pitting corrosion was observed at high concentration of addition.


Oxidation Mechanism Of Hypophosphite, Dong-Bai Sun, Ying Jin, Hong-Ying Yu, De-Jun Yang Feb 1999

Oxidation Mechanism Of Hypophosphite, Dong-Bai Sun, Ying Jin, Hong-Ying Yu, De-Jun Yang

Journal of Electrochemistry

There exist two oxidation current peaks on the anodic polarization curve between -0.7 V and 0 V (SCE) in Na-hypophosphite solution. Peak Ⅰ (-0.55 V, SCE) , which represents the oxidation process from H2PO2- to H2PO3-, has been studied previously. Peak Ⅱ, which is located at the potential about -0.4 V (SCE), is investigated emphatically in this paper. The results show that, peak Ⅰ and Ⅱ are corresponding to two successive steps in oxidation process of H2PO2-, i.e. peak Ⅱ corresponds to the oxidation process of …


Synthesis And Application Of Polymeric Corrosion Inhibitor For Reinforced Concrete, Wei-Wei Lin, Sheng-Xian Wang, Jian-Qing Zhang, Jun Yuan, Zhen-Guo Ji Feb 1999

Synthesis And Application Of Polymeric Corrosion Inhibitor For Reinforced Concrete, Wei-Wei Lin, Sheng-Xian Wang, Jian-Qing Zhang, Jun Yuan, Zhen-Guo Ji

Journal of Electrochemistry

A new polymer E-T was synthesized and used as a corrosion inhibitor for reinforced concrete. The inhibitive behavior and mechanism were studied with linear polarization, Tafel polarization, EIS and XPS method in simulated pore solution system with concrete samples. The result showed that the polymer was a mixing type inhibitor. A 1% dosage was sufficient to imhibit the corrosion of steel in simulated pore solution system. The salt endurance was enhanced from 0.02 mol/L to 0.10 mol/L. The result also showed the good synergetic effect of NaNO2, especially in low NaNO2 concentration. The EIS showed that E-T …


Structural And Electrochemical Studies On Todorokite/Vernadite As Cathodes For Rechargeable Lithium Ion Batteries, Wei Chu, De-Yao Liu, Jin-Kua You, Yong Yang, Zu-Geng Lin Feb 1999

Structural And Electrochemical Studies On Todorokite/Vernadite As Cathodes For Rechargeable Lithium Ion Batteries, Wei Chu, De-Yao Liu, Jin-Kua You, Yong Yang, Zu-Geng Lin

Journal of Electrochemistry

XRD, TEM, ICP, low scan-rate CV and charge/discharge tests were carried out for the studies on the structural and electrochemical behavior of a prepared 3 V manganese oxide cathode for rechargeable lithium ion batteries.XRD analysis revealed that the cathode sample is mainly composed of tunneled Todorokite and layered Vernadite. TEM investigation confirmed that the morphology of the sample is a laminated construction with approximate 10nm layer space. The reversibility of Li+ removal/intercalation and structural stability of this sample framework to lithium insertion are good in CV and charge/discharge tests. The discharge capacities were found to be about 129mAh/g obtained …


Study On Ionic Conductivity Of A Novel Solid State Electrolyte, Ying-Xin Zhao, Chang-Yan Liu Feb 1999

Study On Ionic Conductivity Of A Novel Solid State Electrolyte, Ying-Xin Zhao, Chang-Yan Liu

Journal of Electrochemistry

Various novel predominantly lithium-ion-conducting solid state electrolytes were described, which had high conductivity at room temperature. It comprised low-melting-point eutectic lithium salts in which a small amount of an single ion polyeletrolyte poly(lithium acrylate) was dissolved to rubberize them. The effects of the eutectic and polymer features upon the ionic conductivity were discussed.


A New Cell Structure For Proton Exchange Membrane Fuel Cell, Ming Han, Hong-Feng Xu, Bao-Lian Yi Feb 1999

A New Cell Structure For Proton Exchange Membrane Fuel Cell, Ming Han, Hong-Feng Xu, Bao-Lian Yi

Journal of Electrochemistry

Separating the functions of current collection and gas flow distribution and then to design two separate elements to achieve the desired performance characteristics, a nonconventional cell structure for proton exchange membrane fuel cells bave been developed. The current collector is achieved using a thin stain steel sheet, the gas flow distribution is achieved using a carbon paper that has the desired chemical durabiliy when in contact with the proton exchange membrane. Combining these two separate elements into a single divice yields a bifunctional device that performs as a bipolar separator plate. The advantages of this alternative appproach to making biplar …


Analysis Of Phytoestrogens By High Performance Liquid Chromatography, Anne A. Grippo, Yan Xie, Benjamin L. Rougeau, William V. Wyatt Jan 1999

Analysis Of Phytoestrogens By High Performance Liquid Chromatography, Anne A. Grippo, Yan Xie, Benjamin L. Rougeau, William V. Wyatt

Journal of the Arkansas Academy of Science

Phytoestrogens are biochemicals synthesized in plants which mimic steroidal estrogen activity in mammals. Analysis of these compounds in the legumes which produce them and in body fluids is important to the study of their physiological effects. High pressure liquid chromatography (HPLC) has been found to be an efficient and sensitive method of identification and quantitation of isoflavonoids, one class of phytoestrogen. Here we report the separation of three isoflavonoids, biochanin A, genistein and daidzein using an HPLC system with a Cg reverse phase column and a linear gradient mobile phase containing acetonitrile and acetic acid/water (10/90, v/v) over 60 minutes. …


Synthesis And Molecular Structure Of [Cpru(Pph3)(Pms)2]Otf1.3/4 C2>H4C12, Paul M. Nave, Mark Draganjac, A. W. Cordes, Tosha M. Barclay Jan 1999

Synthesis And Molecular Structure Of [Cpru(Pph3)(Pms)2]Otf1.3/4 C2>H4C12, Paul M. Nave, Mark Draganjac, A. W. Cordes, Tosha M. Barclay

Journal of the Arkansas Academy of Science

No abstract provided.


Reply To Comment On ‘Nondipole Resonant X-Ray-Raman Spectroscopy: Polarized Inelastic Scattering At The K Edge Of Cl2,’, J. D. Mills, J. A. Sheehy, T. A. Ferrett, S. H. Southworth, R. Mayer, Dennis W. Lindle, P. W. Langhoff Jan 1999

Reply To Comment On ‘Nondipole Resonant X-Ray-Raman Spectroscopy: Polarized Inelastic Scattering At The K Edge Of Cl2,’, J. D. Mills, J. A. Sheehy, T. A. Ferrett, S. H. Southworth, R. Mayer, Dennis W. Lindle, P. W. Langhoff

Chemistry and Biochemistry Faculty Research

Mills et al. Reply: In their Comment on our Letter [1], Gel’mukhanov and Ågren [2] reiterate recent assertions [3] based on their earlier theoretical studies [4]. The primary purpose of their Comment is apparently to refute our stated conclusion that core-excited-state localization/ delocalization mechanisms are irrelevant to interpretations of reported Raman scattering experiments on homonuclear diatomic molecules.


The Effect Of Suspended Particles On The Corrosion Resistance Of Electrodeposited Zinc Powders, Qing-Wen Li, Qing Yang, Xi Xia Nov 1998

The Effect Of Suspended Particles On The Corrosion Resistance Of Electrodeposited Zinc Powders, Qing-Wen Li, Qing Yang, Xi Xia

Journal of Electrochemistry

Zinc powders were electrodeposited from ZnCl2 baths with containing suspension of unsoluble particles such as graphite, PbO2, SnO2, TiO2, SiO2 etc.. The structure, morphology and corrosion behavior of zinc powder were analyzed. SEM results showed that the dendritic growth of zinc can be inhibited by applying the suspension method. Suspension of PbO2, SnO2, TiO2, SiO2 and In2O3 could greatly improve the corrosion protection of zinc powder in 5 mol/L KOH. In addition, fractal theory is employed to further explain the results


Oxygen Evolution Behavour On Ni Electrode In Koh Solution, Xiao-Yan Cao, Hua-Tang Yuan, Zuo-Xiang Zhou, Yun-Shi Zhang Nov 1998

Oxygen Evolution Behavour On Ni Electrode In Koh Solution, Xiao-Yan Cao, Hua-Tang Yuan, Zuo-Xiang Zhou, Yun-Shi Zhang

Journal of Electrochemistry

The steady-state polarization curves of oxygen evolution were measured at temperatures between 22~70 ℃ on Ni electrode in 30 wt.% KOH solution by galvanostat methode. The exchange current densities, Tafel slopes and transfer coefficients were studied. It was found that 40 ℃ is a special temperature, near which the kinetic parameters change abrupdy. The Tafel slopes for oxygen evolution reactions at higher overpotentials change from more than 120 mV to about 70 mV when the temperature raises to 40~70 ℃ from 22~35 ℃. Simultaneously, the heat of activation is changes from 79.88 kJ/mol to 55.32 kJ/mol. Moreover, the -(η/Τ) i …


Study On Ni-Co-S-Mo Alloys New Cathode Material For Aquous Electrolysis, Yuan-Shou Xie, Quan-Feng Liu Nov 1998

Study On Ni-Co-S-Mo Alloys New Cathode Material For Aquous Electrolysis, Yuan-Shou Xie, Quan-Feng Liu

Journal of Electrochemistry

The parameters of electrodeposion of Ni-Co-S-Mo alloy were studied. The experimental results indicate that the electrodeposition alloy shows high catalytic activity for hydrogen evolution reaction, as well as better mechanical strength and higher chemical stability. The mechanism of catalytic hydrogen evolution reaction on this type of alloy electrode was also investigated by means of polarization curve and cyclic voltametry.


The Latest World Wide Progress In Solid Oxide Fuel Cell, Yi Jiang Nov 1998

The Latest World Wide Progress In Solid Oxide Fuel Cell, Yi Jiang

Journal of Electrochemistry

Solid oxide fuel cell (SOFC) is a novel, green electricity generation technology, which has been showing rapid development since 1980's. In light of its high efficiency, environmental friendly, fuel adaptability and long term stability, the Research, Development and Demonstration (RD&D) of this hype of full cell have been emphasized in a large number of developed countries. Based on the information communicated at the latest symposium on SOFC held last year in Aachen (Germany) and the knowledge gained through years of research in this field, a comprehensive review on the latest development of the tubular, this planar SOFC as well as …


A Preliminary Study Of The Synthesis Of Tin-Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Han-Xi Yang, Ju-Tang Sun, Xing-Ping Ai Nov 1998

A Preliminary Study Of The Synthesis Of Tin-Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Han-Xi Yang, Ju-Tang Sun, Xing-Ping Ai

Journal of Electrochemistry

An amorphous lithium inserting anode material based on Tin oxide glass was synthesized by salification in solution and its properties on lithium intercalation was investigated by X ray diffraction (XRD), microelectrode voltammetry and charge discharge measurements. The results have shown that this kind of material has considerable electrochemical reversibility toward lithium intercalation deintercalation. The available discharge capacity of the material reaches 430 mAh/g with charge-discharge efficiency over 90%, showing a great potential for practical use.


Studies Of Spinal Li(1+X)Mn(2-X)O4 Rechargeable Lithium Ion Battery, Xiao-Mei Wu, Qing-He Yang, Zhong-Kao Jin, Hao-Qing Wu, Xiang-Fu Zong Nov 1998

Studies Of Spinal Li(1+X)Mn(2-X)O4 Rechargeable Lithium Ion Battery, Xiao-Mei Wu, Qing-He Yang, Zhong-Kao Jin, Hao-Qing Wu, Xiang-Fu Zong

Journal of Electrochemistry

The spinel Li intercalation compound Li1+xMn2-xO4 (0< x <1) was prepared by using techniques of cyclic voltammetry. The electrochemical parameters of Li1+xMn2-xO4 electrode vary as either the starting materials or the synthesis temperature changes. It was found that the initial capacity and reversible behaviors of the Li1+xMn2-xO4 electrode depends on the amount of the excess Li, represented as x in Li1+xMn2-xO4. The reversible of Li intercalation process for Li1+xMn2-xO4 electrode was demonstrate by cyclic voltammograms.


Corrosion Characteristics Of Electrodeposited Ni-Mo-P Alloy Immersed In Nacl Solution, Yue Zeng, Hong-Xin Huang, Xiao-Ming Xiao, Shi-Xun Lian, Su-Wei Yao, He-Tong Guo Nov 1998

Corrosion Characteristics Of Electrodeposited Ni-Mo-P Alloy Immersed In Nacl Solution, Yue Zeng, Hong-Xin Huang, Xiao-Ming Xiao, Shi-Xun Lian, Su-Wei Yao, He-Tong Guo

Journal of Electrochemistry

The corrosion characteristics of electrodeposited Ni-Mo-P alloy immersed in 5wt.% NaCl solution were investigated using immersion, anodic polarization curves, XPS and AES analysis. The corrosion rates of amorphous Ni Mo P alloys are lower than that of crystalline Ni-Mo-P alloys. Anodic polarization curve experiments show that for the electrodeposited Ni-Mo-P alloys, the nickel mol fraction of which has in between 0.719 and 0.868, the corrosion potential moves to positive with the increase of P content, and the peak current value of active region increase with the increase of Mo content in alloys, though the effects of P content on the …


Studies On The Inclusion Behavior Of Cyclodextrins With Ketoprofen By Electrochemical Methods, Jun Gu, Yong Zhang, Jin-Hao Pan Nov 1998

Studies On The Inclusion Behavior Of Cyclodextrins With Ketoprofen By Electrochemical Methods, Jun Gu, Yong Zhang, Jin-Hao Pan

Journal of Electrochemistry

The influences of cyclodextrins and their derivatives on the electrochemical behavior of ketoprofen were studied. The inclusion constants of ketoprofen with β-CD, HP-β-CD and methyl β-CD and the influences of temperature on the inclusion actions were also investigated. The inclusion phenomena is explained with the thermodynamics parameters of the inclusion complexes.


Direct Electro-Oxidation Synthesis Of D-Arabinose On Spectroscopic Graphite Electrode, Hei Wei, Huang Ying Nov 1998

Direct Electro-Oxidation Synthesis Of D-Arabinose On Spectroscopic Graphite Electrode, Hei Wei, Huang Ying

Journal of Electrochemistry

D Arabinose synthesized by direct electro-oxidative decarboxylation of D gluconate on graphite electrode from aqueous solutions. The effects of D gluconate concentration, electrolysis potential, temperature and electrolyte composition on the current efficiency and product yield of electrosynthsis are discussed. The laboratory scale electrosynthesis was achieved with flow through cell. The optimum technology conditions for electrosynthesis were obtained with orthogonal design method. Both galvanostatic and potentionstatic conditions have been exploited, the later was found to be more effective.


Study On Electrosynthesis Of Butyl Butyrate At Conducting Oxide Anode Support On Titanium, Jun-Xiang He, Jin-Cheng Zhou, Kang-Ning Chen Nov 1998

Study On Electrosynthesis Of Butyl Butyrate At Conducting Oxide Anode Support On Titanium, Jun-Xiang He, Jin-Cheng Zhou, Kang-Ning Chen

Journal of Electrochemistry

Synthesis of butyl butyrate by direct electroxidation of n butyl alcohol and the electrochemical behaviors of several selected conducting oxide electrodes (Pb/PbO2, Ti/PbO2, i/SnO2+Sb2O3/PbO2 and Ti/SnO2+Sb2O3+PdOx/PbO2) have been investigated. The results demonstrated that the intermediate layers of SnO2, Sb2O3 and PdOx could significantly decrease the interfacial resistance of the electrodes, and that the Ti/SnO2+Sb2O3+PdOx/PbO2 electrode possessed better electrocatelytic performance than others.


Electrochemical Investigation Of Effect Of Br- On Redox Behavior Of (Tpp)Co, Chuan-Wei Yan, Hai-Chao Lin, Xiang-Qin Lin Nov 1998

Electrochemical Investigation Of Effect Of Br- On Redox Behavior Of (Tpp)Co, Chuan-Wei Yan, Hai-Chao Lin, Xiang-Qin Lin

Journal of Electrochemistry

The effect of Br- anion on electrochemical behavior of (TPP)Co was investigated in 1,2 dichloroethane solution by microelectrode and thin layer cyclic voltammetry technique. It was found that the axially coordination of one Br- anion to (TPP)Co(Ⅲ)(Br-)2 shifts the potential of porphyrin system to more positive value. The reduction peak of 0.12 V (vs.SCE) is attributed to the reduction of (TPP)Co(Ⅲ)(Br-). It is also postulated that the reduction of (TPP)Co(Ⅲ)(Br-)2 occurred at a more negative potential where the reduction of the Co(Ⅱ)/Co(Ⅰ) process happened.


The Study On The Performance Of Mcfc Matrix Prepared By Flow Cast, Hua-Xin Lin, Bao-Lian Yi, Nai-Chao Li, Tian-Xi Qu, En-Jun Zhang, Lian-Yin Kong, Ying-Cai Chen Nov 1998

The Study On The Performance Of Mcfc Matrix Prepared By Flow Cast, Hua-Xin Lin, Bao-Lian Yi, Nai-Chao Li, Tian-Xi Qu, En-Jun Zhang, Lian-Yin Kong, Ying-Cai Chen

Journal of Electrochemistry

The matrix for MCFC were prepared by flow cast technique which gives reproducible and reliable results. Its mean pore radius is about 0.18 μm, and the porosity is about 65%. The performance of MCFC stacked with this type of matrix is 0.854 V at 200 mA/cm2.


Primary Research Of Reversible Proton Exchange Membrane Regenerative Fuel Cells, Zhi-Gang Shao, Bao-Lian Yi, Ming Han Nov 1998

Primary Research Of Reversible Proton Exchange Membrane Regenerative Fuel Cells, Zhi-Gang Shao, Bao-Lian Yi, Ming Han

Journal of Electrochemistry

In this paper, we report the results of our studies on regenerative proton exchange membrane fuel cell (RPEMRFC) catalysts, electrode preparation and their performances. The Pt catalyst for the oxygen electrode was replaced by 60 w%Pt + 40 w%IrO2 which reduces polarization by 0.2 V in a polymer protone exchange membrane fuel cell. The cycle performance of RPEMRFC was found to be manly effected by the stability of the diffiusion layer of bifunctional oxygen electrode.


Study Of The Effect Of Rare Earth Ions On Dna Using Cyclic Voltammetry And Spectroscopy, Hei-Bai Shen, Yu-Zhuan Kang, Hai-Feng Yang, Lin Yu, Zong-Rang Zhang Nov 1998

Study Of The Effect Of Rare Earth Ions On Dna Using Cyclic Voltammetry And Spectroscopy, Hei-Bai Shen, Yu-Zhuan Kang, Hai-Feng Yang, Lin Yu, Zong-Rang Zhang

Journal of Electrochemistry

The interaction between rare earth ions(e.g. Eu3+ ,Ce3+, Er3+, Sm3+, Tb3+, La3+ and Nd3+) and DNA had been investigated by using Cyclic Voltammetry, Ultraviolet and Raman Spectroscopy. After the adding of Ce3+ ion to DNA solution, the cathodic peak current of Ce3+ ion reduction was found to decrease obviously, and the anodic peak current to decrease even more significantly. Differential UV spectra of Ce3+ ion depicted hyperchromic effect after the reaction of these two species and a new peak of 272 nm was found. Differential …


The Study Of Poly [N-(3-Ferrocene Acetamino Propyl- Pyrrole] Film Modified Glucose Electrode, Cheng-Yun Tian, Jing Chen, Li Zhang Nov 1998

The Study Of Poly [N-(3-Ferrocene Acetamino Propyl- Pyrrole] Film Modified Glucose Electrode, Cheng-Yun Tian, Jing Chen, Li Zhang

Journal of Electrochemistry

A poly [N-(3-ferrocene-acetamino-propyl-pyrrole)] film modified electrode was fabricated and studied by cyclic voltammetric method. The result shows that the modified electrode can give stable redox peaks of ferrocene, and an obvious catalytic peak due to glucose. This modified electrode was used to tabricate a glucose sensor which operates at +0.2 V, so that the ascorbic acid or uric acid doesn't affect the accuracy detection of glucose concentration. The sensor has a linear range of 0.1~10 mmol/L glucose, which the period of long term stability and response time of the sensor are about ten days and 2 min.


Study On The Ti/Sno2/Pbo2 Anode In Sulphuric Acid Solution, Yao-Gang Li, Yan-Pin Shun, Wen-Lin Xu Nov 1998

Study On The Ti/Sno2/Pbo2 Anode In Sulphuric Acid Solution, Yao-Gang Li, Yan-Pin Shun, Wen-Lin Xu

Journal of Electrochemistry

The Ti/SnO2/PbO2 electrode, prepared by the electrodeposition method, was tested as the anode for the oxygen evolution reaction in 1 mol/L H2SO4 solution and examined by means of EDS, SEM and XRD. The electrocatalytic activity and the electrochemical stability of the prepared electrode were found to be superior.


High-Resolution Electron Time-Of-Flight Apparatus For The Soft-X-Ray Region, Oliver Hemmers, S. B. Whitfield, P. Glans, H. Wang, Dennis W. Lindle, R. Wehlitz, I. A. Sellin Nov 1998

High-Resolution Electron Time-Of-Flight Apparatus For The Soft-X-Ray Region, Oliver Hemmers, S. B. Whitfield, P. Glans, H. Wang, Dennis W. Lindle, R. Wehlitz, I. A. Sellin

Environmental Studies Faculty Publications

A gas-phase time-of-flight (TOF) apparatus, capable of supporting as many as six electron-TOF analyzers viewing the same interaction region, has been developed to measure energy- and angle-resolved electrons with kinetic energies up to 5 keV. Each analyzer includes a newly designed lens system that can retard electrons to about 2% of their initial kinetic energy without significant loss of transmission; the analyzers can thus achieve a resolving power (E/ΔE) greater than 104 over a wide kinetic-energy range. Such high resolving power is comparable to the photon energy resolution of state-of-the-art synchrotron–radiation beamlines in the soft …


Photofragmentation Of Third-Row Hydrides Following Photoexcitation At Deep-Core Levels, D. Hansen, M. E. Arrasate, J. Cotter, G. R. Fisher, Oliver Hemmers, K. T. Leung, Jon C. Levin, R. Martin, Paul Neill, Rupert C. Perera, I. A. Sellin, Marc Simon, Y. Uehara, B. Vanderford, S. B. Whitfield, Dennis W. Lindle Nov 1998

Photofragmentation Of Third-Row Hydrides Following Photoexcitation At Deep-Core Levels, D. Hansen, M. E. Arrasate, J. Cotter, G. R. Fisher, Oliver Hemmers, K. T. Leung, Jon C. Levin, R. Martin, Paul Neill, Rupert C. Perera, I. A. Sellin, Marc Simon, Y. Uehara, B. Vanderford, S. B. Whitfield, Dennis W. Lindle

Environmental Studies Faculty Publications

The relaxation dynamics of HCl, DCl, H2S, and D2S following photoexcitation in the vicinities of the Cl and S K-shell thresholds (∼2.8keV for Cl, ∼2.5 keV for S) were studied by means of ion time-of-flight mass spectroscopy. In all cases, the onset of pre-edge core-shell photoionization precedes the formation on resonance of a significant amount of neutral hydrogen as well as postcollision-interaction effects above threshold. Examination of the width of the H+ peak in spectra taken with the analyzer parallel and perpendicular to the polarization vector of the incident light indicates that on resonance, the …


Chemical Modification Of Cvd Diamond Electrodes, Robert Matthew Johnson Oct 1998

Chemical Modification Of Cvd Diamond Electrodes, Robert Matthew Johnson

Chemistry & Biochemistry Theses & Dissertations

The micro-array behavior of boron doped CVD diamond thin film electrodes has been studied in acetonitrile containing two redox couples. The analytical technique employed in these studies was cyclic voltammetry. One system is 0.4 mM ferrocene containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAH). This reversible redox system is not only well-known, but also involves only one electron transfer with no breakage/formation of chemical bonds, thus making it a simple system for analysis. The second test is 0.8 mM cobaltocenium hexafluorophosphate, with 0.4 mM ferrocene as an internal standard. Unlike ferrocene, which is neutral initially, cobaltocenium is positively charged, and is reduced …


Auger Resonance Decay Process In Ar 2p Shell Excitation And Ionization, Y. Lu, Wayne C. Stolte, J.A. R. Samson Oct 1998

Auger Resonance Decay Process In Ar 2p Shell Excitation And Ionization, Y. Lu, Wayne C. Stolte, J.A. R. Samson

Chemistry and Biochemistry Faculty Research

The production and subsequent autoionization of the Ar+ (1D2)6d1 satellite state that is formed either by shake-up or recapture during the Auger decay of a 2p vacancy in Ar has been studied by photoelectron spectroscopy in the energy region from 243 to 256 eV. The creation of near zero energy electrons below and immediately above the Ar 2p ionization threshold is discussed. Some ambiguous points in previous studies are clarified.