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Physical Chemistry

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2009

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Articles 1 - 30 of 162

Full-Text Articles in Chemistry

Highly Nitrated Cyclopropanes As New High Energy Materials: Dft Calculations On The Properties Of C3H6−N(No2)N (N=3–6), Aloysus K. Lawong, David W. Ball Dec 2009

Highly Nitrated Cyclopropanes As New High Energy Materials: Dft Calculations On The Properties Of C3H6−N(No2)N (N=3–6), Aloysus K. Lawong, David W. Ball

Chemistry Faculty Publications

As part of a continuing study of new potential high energy materials, here we present results of calculations on cyclopropane molecules with three or more nitro groups. DFT calculations suggest that all molecules can exist as minimum-energy stationary states. Energy calculations indicate that some nitrocyclopropanes have a specific enthalpy of decomposition in excess of 8kJg−1, suggesting that they be explored as new potential high energy materials.

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Indirect Gravimetric Determination Of Waters Of Hydration, Marina C. Koether Dec 2009

Indirect Gravimetric Determination Of Waters Of Hydration, Marina C. Koether

Faculty and Research Publications

An alternate gravimetric experiment is described that can be employed in the general chemistry or the quantitative analysis laboratory course. The procedure takes less time than conventional methods and introduces students to waters of hydration and indirect determinations.

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Synthesis And Development Of Novel Fullerene-Based Structures For Photovoltaics, Electronic Applications And Mri Contrast Agents, Manuel Chaur Dec 2009

Synthesis And Development Of Novel Fullerene-Based Structures For Photovoltaics, Electronic Applications And Mri Contrast Agents, Manuel Chaur

All Dissertations

Metallic nitride endohedral metallofullerenes (EMFs) are one of the most interesting types of metallofullerenes due to their high yields and interesting electronic properties. The synthesis of these compounds allows the encapsulation of different metals inside fullerenes making it possible to combine the properties of the metal with those of the fullerene. Their interesting electrochemical and optical features make them potential candidates for several applications such as molecular electronics, biomedical imaging, non-linear optical devices, and magnetic resonance imaging (MRI) agents. This thesis reports the synthesis of novel metallic nitride EMFs based on Gd, Nd, Pr, Ce and La. These families of …

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Electrooxidation Of Formic Acid On Pd-Ni Alloy Film Electrode-The Effect Of Dealloying, Chao Wang, Fei-Fei Shi, Jin-Yi Wang, Han-Xuan Zhang, Wen-Bin Cai Nov 2009

Electrooxidation Of Formic Acid On Pd-Ni Alloy Film Electrode-The Effect Of Dealloying, Chao Wang, Fei-Fei Shi, Jin-Yi Wang, Han-Xuan Zhang, Wen-Bin Cai

Journal of Electrochemistry

A Pd-Ni alloy film was electrodeposited on Au disc electrode at a constant potential from a weakly basic bath containing PdCl2,NiSO4 and ethylenediamine.The as-deposited film was then subjected to potential cycling in a perchloric acid solution for surface dealloying treatment.The dealloyed Pd-Ni film electrode was examined for the electrocatalytic oxidation of formic acid,and compared with the as-deposited one as well as a Pd film electrode.The FE-SEM and electrochemical measurements on the Pd-Ni films revealed that the dealloying treatment caused a surface roughening and an increase in specific surface reaction area.The ICP-AES and XPS analyses demonstrated that the preferential dissolution of …

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Electrocatalysis In Polymer Electrolyte Membrane Fuel Cells, Li Li, Si-Guo Chen, Xue-Qiang Qi, Yao-Qiong Wang, Meng-Bo Ji, Lan-Lan Li, Zi-Dong Wei Nov 2009

Electrocatalysis In Polymer Electrolyte Membrane Fuel Cells, Li Li, Si-Guo Chen, Xue-Qiang Qi, Yao-Qiong Wang, Meng-Bo Ji, Lan-Lan Li, Zi-Dong Wei

Journal of Electrochemistry

This review presents the study of Chongqing University in electrocatalysis for polymer electrolyte membrane fuel cells(PEMFCs).Based on the understanding to the performance degradation of PEMFCs' catalysts,the university has being concentrated on how to increase the activity,stability and utility of noble metal catalysts.It covers the molecular design of near-surface alloy catalysts for improvement of activity to oxygen reduction reaction(ORR) and resistance to foreign poison species,selective deposition of Pt on the so-called "three-phase interface" for a high Pt utility,and invention of anti-flooding electrode against water flooding in the catalyst layer of the membrane assemble electrode(MEA),and so on.The catalytic mechanism of electrode reactions …

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Platinum Modified With Hydrogen Molybdenum/Tungsten Bronze As Electrocatalysts For Direct Small Organic Molecule Fuel Cell, Wei-Shan Li, Li-Peng Tian, Jun-Hua Du, Hong-Liang Huang, Wei Li, Li-Xia Zhang, Hong-Yan Yang, Pan-Pan Guo, Zhi-Hui Zhou, Xing-De Xiang, Zhao Fu Nov 2009

Platinum Modified With Hydrogen Molybdenum/Tungsten Bronze As Electrocatalysts For Direct Small Organic Molecule Fuel Cell, Wei-Shan Li, Li-Peng Tian, Jun-Hua Du, Hong-Liang Huang, Wei Li, Li-Xia Zhang, Hong-Yan Yang, Pan-Pan Guo, Zhi-Hui Zhou, Xing-De Xiang, Zhao Fu

Journal of Electrochemistry

There are several problems that limit the application of direct small organic fuel cell,including the use of precious platinum and the activity loss of platinum due to the intermediates poisons from the oxidation of small organic molecules.These problems have attracted wide interest and many solutions have been proposed.We have developed a new method to reduce the platinum usage and improve its activity,based on the modification of platinum with hydrogen molybdenum/tungsten bronze(HxMo(W)O3,0

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Preparation Of Polyaniline/Polyester Conductive Fabric Via In-Situ Polymerization, Fang Na, Wei Wang Nov 2009

Preparation Of Polyaniline/Polyester Conductive Fabric Via In-Situ Polymerization, Fang Na, Wei Wang

Journal of Electrochemistry

The formation of PANI coating on the surface of PET fiber and fabric was obtained by in-situ polymerization method.The coating′s thickness was about 1～2 μm.Orthogonal test methodology was used to analyze the main factors of preparation of PANI / PET conductive fabric.The effects of the aniline monomer concentration,oxidant: aniline molar ratio,doping acid concentration and types,reaction time on the conductivities of the fabric were studied.The structure of the polymer were characterized by SEM,FTIR and XRD.The results indicated that there was uniform and continuous polyaniline film on the surface of polyester fabric.The contents of oxidation and reduction of polyaniline molecular chain structure …

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Electrocatalytic Performance Of Carbon Supported Ir Catalysts With Different Ir Loadings For Ammonia Oxidation, Yu-Zhi Jiang, Qing-Mei Kong, Tian-Hong Lu, Yi-Ming Zhou, Ya-Wen Tang Nov 2009

Electrocatalytic Performance Of Carbon Supported Ir Catalysts With Different Ir Loadings For Ammonia Oxidation, Yu-Zhi Jiang, Qing-Mei Kong, Tian-Hong Lu, Yi-Ming Zhou, Ya-Wen Tang

Journal of Electrochemistry

The electrocatalytic performance of the Ir/C catalyst as the anodic catalyst in the amperometric and electrochemical NH3 sensor was investigated.The experimental results illustrated that in the NaClO4 neutral electrolyte,the electrocatalytic performance of the Ir/C catalyst for the NH3 oxidation is related to the Ir loading in the Ir/C catalyst.Among the Ir/C catalysts with different Ir loading,the best electrocatalytic activity,stability and sensitivity were achieved by the Ir/C catalyst with 10% Ir loadings.In addition,the current densities of the NH3 oxidation at the Ir/C catalysts with the different Ir loadings were linearly proportional to the NH3 concentration.The Ir/C catalyst has a potential application …

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Electrocatalysis Of Myoglobin-Chitosan-Au Colloid Film Modified Glass Carbon Electrode, Yu-Hua Qin, Jun Guo, Hui Xu, Li-Heng Zhou, Sheng-Tian Wang Nov 2009

Electrocatalysis Of Myoglobin-Chitosan-Au Colloid Film Modified Glass Carbon Electrode, Yu-Hua Qin, Jun Guo, Hui Xu, Li-Heng Zhou, Sheng-Tian Wang

Journal of Electrochemistry

The cyclic voltammgram of Mb/AAO/Au Colloid/GCE shows a pair of well-defined and nearly reversible peaks at about-0.20 V(vs.Ag/AgCl) in 0.1 mol/L NaAc-HAc buffer(pH = 5.4),being the characteristic peaks of the Mb heme Fe(Ⅲ) / Fe(Ⅱ)redox couples.The electron transfer between Mb and the electrode was greatly enhanced under present testing conditions.The effects of scan rate,pH and buffers concentration on the electrochemical behaviors of Mb were studied in detail.Position of the Soret absorbance band suggested that Mb in chitosan-colloidal gold hept its secondary structure similar to the native states.Oxygen was catalytically reduced by Mb in chitosan-colloidal gold films.

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Progresses In Electrocatalysis Of Nanomaterials—Tuning The Surface Structure And Property Of Electrocatalysts, Yan-Xia Jiang, Na Tian, Zhi-You Zhou, Sheng-Pei Chen, Shi-Gang Sun Nov 2009

Progresses In Electrocatalysis Of Nanomaterials—Tuning The Surface Structure And Property Of Electrocatalysts, Yan-Xia Jiang, Na Tian, Zhi-You Zhou, Sheng-Pei Chen, Shi-Gang Sun

Journal of Electrochemistry

The property of an electrocatalyst depends strongly on its surface structure.The study of surface structure-catalytic functionality is the base of design and preparation of electrocatalysts of high activity,high stability and high selectivity at microstructure level.In this paper,based mainly on our results concering hydrogen and oxygen adsorption-desorption,ethylene glycol oxidation and CO2 reduction,the research progresses in tuning the surface structure and property of electrocatalysts are summarized.This paper overviews firstly the cyclic voltammetric characteristics,electrocatalytic properties of platinum single crystal planes lying on different crystallographic zones of the unit stereographic triangle of face-centered cubic(fcc) metals.Next,the innovation of electrochemical methods to control the surface structure …

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Synthesis And Electrocatalytic Properties Of Ni-Pd/C Catalysts With Pd-Enriched Surface, Yu-Mei Chen, Zhi-Xiu Liang, Sheng-Li Chen Nov 2009

Synthesis And Electrocatalytic Properties Of Ni-Pd/C Catalysts With Pd-Enriched Surface, Yu-Mei Chen, Zhi-Xiu Liang, Sheng-Li Chen

Journal of Electrochemistry

The Ni-Pd alloy catalysts with Pd-enriched surface were synthesized through a modified polyol process.The synthesized materials were investigated by XRD and electrochemical methods,and tested as electrocatalysts for CH3OH-tolerant oxygen reduction.The results indicated that the synthesized Ni-Pd nanoparticles possess multiple phases containing Pd-Ni alloy and pure Ni.Comparing with Pd/C,the prepared Ni-Pd/C nanoparticles exhibited better resolved voltammetric peaks between the hydrogen absorption and adsorption,and positively shifted current peaks for the reduction of Pd oxide.The prepared Ni-Pd alloys with Pd-enriched surface have significantly enhanced ORR activity and improved CH3OH tolerance as comparing with Pd/C catalysts.

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Complex Reduction Preparation Of Carbon Supported Pd Nanoparticle Catalyst And Its Electrocatalysis For Formic Acid Oxidation, Wei He, Yong-Yin Kang, Chong Du, Zhi-Qing Zou, Xiao-Gang Zhang, Hui Yang Nov 2009

Complex Reduction Preparation Of Carbon Supported Pd Nanoparticle Catalyst And Its Electrocatalysis For Formic Acid Oxidation, Wei He, Yong-Yin Kang, Chong Du, Zhi-Qing Zou, Xiao-Gang Zhang, Hui Yang

Journal of Electrochemistry

A simple procedure involved the complexing of PdCl2 with sodium citrate followed by ethylene glycol reduction has been employed for the preparation of carbon-supported Pd nanoparticles(Pd/C).The XRD and TEM characterizations indicate that Pd nanoparticles with a small particle size were well-dispersed on carbon support.The mean particle sizes of the Pd/C catalysts were found to be increased from 2.7 to 5.8 nm with heat-treatments at different temperature.The mass activity of the Pd/C catalyst for formic acid electrooxidation increased with the decrease in Pd particle size.However,the specific activity increased with Pd particle size.Furthermore,the Pd/C catalyst with a particle size of ca.3.6 nm …

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Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun Nov 2009

Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun

Journal of Electrochemistry

Adsorption and reduction of NO on electrode of Pt nanoparticles in acid solutions were studied by means of cyclic voltammetry(CV) and in-situ FTIR spectroscopy.The results indicated that the reduction of NO is a complicated process including the adsorption of NO on electrode surface.Two types of surface-bonded NO were determined on Pt nanoparticles.The weakly adsorbed NO was reduced between 0.6 V and-0.05 V,which yielded nitrous oxide(N2O) and ammonium(NH+4) as products;while the strongly bonded NO was reduced at more negative potentials between-0.05V and-0.15V,producing only NH4+ species.

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Research Progress Of Synergistic Effect Of Metal Oxides On Pt-Based Catalysts, Hui-Ping Yuan, Xun Guo, Xin-Ping Qiu, Wen-Tao Zhu, Li-Quan Chen Nov 2009

Research Progress Of Synergistic Effect Of Metal Oxides On Pt-Based Catalysts, Hui-Ping Yuan, Xun Guo, Xin-Ping Qiu, Wen-Tao Zhu, Li-Quan Chen

Journal of Electrochemistry

In this paper,the work of Pt-based catalysts modified by metal oxides as the anode catalysts of direct methanol fuel cell(DMFC) is reviewed.The relationship between the structure and the composition of the catalysts and the reaction mechanism,exiting problems and developing direction are discussed.

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Highly Durable Pt/Ruo_2/C Catalyst For The Cathode Of Direct Methanol Fuel Cells, Chun-Yu Du, Tao Dong, Ge-Ping Yin, Peng-Fei Shi Nov 2009

Highly Durable Pt/Ruo_2/C Catalyst For The Cathode Of Direct Methanol Fuel Cells, Chun-Yu Du, Tao Dong, Ge-Ping Yin, Peng-Fei Shi

Journal of Electrochemistry

Instability of the carbon-supported Pt(Pt/C) catalyst at the cathode is one of the key technical challenges for the development of Direct Methanol Fuel Cells(DMFCs).In this paper,an efficient approach to enhancing the stability of the cathode catalyst was explored by designing and synthesizing a novel nanocomposite support,RuO2 coated carbon black(RuO2/C).Firstly,a wet chemical method was employed to synthesize the RuO2/C nanocomposite,from which Pt/RuO2/C catalyst was further prepared by a microwave method.The morphology and crystalline structure of the RuO2/C support and Pt/RuO2/C catalyst were then characterized by TEM and XRD.Finally,the electrochemical performance of the RuO2/C support and Pt/RuO2/C catalyst was analyzed by cyclic …

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Preparation Of Pt Nanoflower/Zno Composites Arrays And Their Electrocatalysis For Methanol Oxidation, Li Gao, Yi-Feng E, Lou-Zhen Fan Nov 2009

Preparation Of Pt Nanoflower/Zno Composites Arrays And Their Electrocatalysis For Methanol Oxidation, Li Gao, Yi-Feng E, Lou-Zhen Fan

Journal of Electrochemistry

The Pt nanoflower/ZnO(PtNF/ZnO) nanorod composites arrays were electrochemically prepared by controlling the hydrophobicity and the hydrophilicity of ZnO nanorods arrays.The Pt nanoflowers grew on the tip of ZnO nanorods,which maintain the vertical array of Zno nanorods with a high degree of size uniformity and high surface area.Compared with Pt nanoparticle covered ZnO nanorod arrays,which were prepared by controlling the hydrophilicities of ZnO nanorods and Pt nanoparticles,the PtNF/ZnO displayed highest electrocatalytic activities for the oxidation of methanol.

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Enhanced Visible Light Photoelectrochemical Performances With Nitrogen Doped Tio_2 Nanowire Arrays, Xiao-Jun Lv, Yue-Ming Li, Hao Zhang, Da Chen, Hensel Jennifer, Z Zhang Jin, Jing-Hong Li Nov 2009

Enhanced Visible Light Photoelectrochemical Performances With Nitrogen Doped Tio_2 Nanowire Arrays, Xiao-Jun Lv, Yue-Ming Li, Hao Zhang, Da Chen, Hensel Jennifer, Z Zhang Jin, Jing-Hong Li

Journal of Electrochemistry

Self-organized anodic anatase TiO2nanowire arrays doped with nitrogen have been successfully fabri-cated and their photoelectrochemical(PEC) properties have been characterized and found to be substantially im-proved compared to undoped nanowires or commercial P25 nanoparticles.Photocurrent measured with monochro-matic incident light showed that the incident photon-to-current efficiency(IPCE,%) values of nanowire arrayelectrodes with or without N-doping were obviously higher than that of commercial P25 nanoparticle electrodes,and nitrogen-doped TiO2nanowire arrays(NTNA) had noticeable absorption in the visible region.The NTNAelectrodes showed the highest photocurrent density and power conversion efficiency under 100 mW/cm2visiblelight illumination.A maximumolphotoconversion efficiency of 0.52% was achieved for the NTNA sample at anapplied potential of …

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Synthesis Of Α-Mno_2 Microspheres For The Application In Supercapacitor, Liang Wang, Gui-Chang Liu, Zhi-Cong Shi Nov 2009

Synthesis Of Α-Mno_2 Microspheres For The Application In Supercapacitor, Liang Wang, Gui-Chang Liu, Zhi-Cong Shi

Journal of Electrochemistry

The MnO2 microspheres were prepared through the oxidation of KMnO4 and MnCO3 microspheres precursor.The microstructure and supercapacitor properties of MnO2 were characterized by XRD,SEM and CV.The results show that MnO2 was in a poorly crystalline state with α-crystallographic form,the size of microspheres typically ranged from 0.5 to 2 μm.Loading 5 mg·cm-2 MnO2 microspheres had excellent capacitance behaviors in 2 mol·L-1(NH4)2SO4 solution.The specific capacitance was 135.6 F·g-1 with the scan rate at 2 mV·s-1,and 118.8 F·g-1 with the large scan rate at 100 mV/s.Coulumbic efficiency was still above 87.8% in the 500 cycles,and the specific capacitance of the 500th cycle was …

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Enhanced [Ru(Bpy)_3]~(2+)-Mediated Oxidation Of Guanine Prompted By Dhp, Bao-Lian Zhang, Wei Hong, Bao-Yi Lu, Hong Li Nov 2009

Enhanced [Ru(Bpy)_3]~(2+)-Mediated Oxidation Of Guanine Prompted By Dhp, Bao-Lian Zhang, Wei Hong, Bao-Yi Lu, Hong Li

Journal of Electrochemistry

The effects of dihexadecyl phosphate(DHP) and multi-walled carbon nanotubes(MWNTs) on the oxidation of guanine mediated by[Ru(bpy)3]2+ on the ITO electrode have been investigated by cyclic voltammetry and differential pulse voltammetry.The results showed that [Ru(bpy)3]2+ can mediate the oxidation.In the range from 0.01 to 0.15 mmol·L-1,peak currents for guanine oxidation mediated by [Ru(bpy)3]2+ increased with the rise of DHP concentrations.On the contrary,cationic surfactant HTAC has the ability to weaken the mediated oxidation of guanine.In addition,the oxidative mechanism of guanine mediated by [Ru(bpy)3]2+ with the participation of DHP is discussed.

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Electrocatalytic Activities Of Au-Mmni_(3.2)Al_(0.2)Mn_(0.6)Co_(1.00) For Borohydride Oxidation, Gui-Ling Wang, Jin-Cheng Liu, Ke-Ning Sun, Dian-Xue Cao Nov 2009

Electrocatalytic Activities Of Au-Mmni_(3.2)Al_(0.2)Mn_(0.6)Co_(1.00) For Borohydride Oxidation, Gui-Ling Wang, Jin-Cheng Liu, Ke-Ning Sun, Dian-Xue Cao

Journal of Electrochemistry

In this work,the electrocatalytic activities of MmNi3.2Al0.2Mn0.6Co1.0,NaOH treated MmNi3.2Al0.2Mn0.6Co1.0 and Au-MmNi3.2Al0.2Mn0.6Co1.0 obtained after NaOH treatment(Mm: misch metal) for NaBH4 oxidation were reported.The electrodes were prepared by electrodeposition,their morphologies were analysized by SEM,their electrocatalytic properties were studied by the linear sweeping test.It was found that the oxidation current density of the Au-MmNi3.2Al0.2Mn0.6Co1.0 was 60 mA·cm-2,it was 3.5 times higher than that at the MmNi3.2Al0.2Mn0.6Co1.0 electrode.In addition,the oxidation current density at the Au-MmNi3.2Al0.2Mn0.6Co1.0 electrode immersed in the electrolyte solution for 10 hours was 184 mA·cm-2.

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Indirect Electrosynthesis Of Double Aldehyde Starch Using Pb-(Bro_3~-/Br~-) As Electro-Catalytic Mediator, Chen Ni-Na, Chen Ri-Yao, Xi Zheng, Chen Xiao, Zhen Chen Nov 2009

Indirect Electrosynthesis Of Double Aldehyde Starch Using Pb-(Bro_3~-/Br~-) As Electro-Catalytic Mediator, Chen Ni-Na, Chen Ri-Yao, Xi Zheng, Chen Xiao, Zhen Chen

Journal of Electrochemistry

In this paper,Nafion membrane was used as the separator in the electrolysis cell to indirectly electro-generating the double aldehyde starch(DAS) with BrO-3/Br-as a redox mediator and Pb as an anode.Effects of temperature,concentration of sulfuric acid and starch on the electro-oxidation of DAS were discussed.The steady state polarization curves were obtained.The experiment results showed that the current efficiency was over 50% when the electrolysis current density was 15mA/ cm2.

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Fragmentation Properties Of Three-Membered Ring Heterocyclic Molecules By Partial Ion Yield Spectroscopy: C2h4o And C2h4s, Wayne C. Stolte, I. Dumitriu, S-W Yu, Gunnar Ohrwall, Maria Novella Piancastelli, Dennis W. Lindle Nov 2009

Fragmentation Properties Of Three-Membered Ring Heterocyclic Molecules By Partial Ion Yield Spectroscopy: C2h4o And C2h4s, Wayne C. Stolte, I. Dumitriu, S-W Yu, Gunnar Ohrwall, Maria Novella Piancastelli, Dennis W. Lindle

Chemistry and Biochemistry Faculty Research

We investigated the photofragmentation properties of two three-membered ring heterocyclic molecules, C2H4O and C2H4S, by total and partial ion yield spectroscopy. Positive and negative ions have been collected as a function of photon energy around the C 1s and O 1s ionization thresholds in C2H4O, and around the S 2p and C 1s thresholds in C2H4S. We underline similarities and differences between these two analogous systems. We present a new assignment of the spectral features around the C K-edge and the sulfur L2 …

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Absolute Nitrogen Atom Density Measurements By Two-Photon Laser-Induced Fluorescence Spectroscopy In Atmospheric Pressure Dielectric Barrier Discharges Of Pure Nitrogen, Et-Touhami Es-Sebbar, Christian Sarra-Bournet, Nicolas Naudé, Françoise Massines, Nicolas Gherardi Oct 2009

Absolute Nitrogen Atom Density Measurements By Two-Photon Laser-Induced Fluorescence Spectroscopy In Atmospheric Pressure Dielectric Barrier Discharges Of Pure Nitrogen, Et-Touhami Es-Sebbar, Christian Sarra-Bournet, Nicolas Naudé, Françoise Massines, Nicolas Gherardi

Dr. Et-touhami Es-sebbar

In this paper, two-photon absorption laser induced fluorescence spectroscopy is used to follow the nitrogen atom density in flowing dielectric barrier discharges fed with pure nitrogen and operating at atmospheric pressure. Two different dielectric barrier discharge regimes are investigated: the Townsend regime, which is homogeneous although operating at atmospheric pressure, and the more common filamentary regime. In both regimes, densities as high as 3x1014 /cm3 are detected. However, the N atoms kinetic formation depends on the discharge regime. The saturation level is reached more rapidly with a filamentary discharge. For a given discharge regime, the N atom density depends strongly …

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Contributions To The Development Of The S.E.T.U.P. (Experimental And Theoretical Simulations Useful For Planetology) Project, E. Arzoumanian, C. Romanzin, M-C. Gazeau, Et. Es-Sebbar, A. Jolly, S. Perrier, Y. Benilan Oct 2009

Contributions To The Development Of The S.E.T.U.P. (Experimental And Theoretical Simulations Useful For Planetology) Project, E. Arzoumanian, C. Romanzin, M-C. Gazeau, Et. Es-Sebbar, A. Jolly, S. Perrier, Y. Benilan

Dr. Et-touhami Es-sebbar

No abstract provided.

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Multiwavelength Studies For Titan's Atmospheric Composition Analysis, Y. Benilan, Et. Es-Sebbar, N. Fray, M-C. Gazeau, A. Jolly, M. Schwell, J. Guillemin Oct 2009

Multiwavelength Studies For Titan's Atmospheric Composition Analysis, Y. Benilan, Et. Es-Sebbar, N. Fray, M-C. Gazeau, A. Jolly, M. Schwell, J. Guillemin

Dr. Et-touhami Es-sebbar

Titan's atmosphere mainly made of nitrogen and methane is rich in organic molecules. Hydrocarbons are formed from the photolytic dissociation of CH4 and nitriles are created by dissociation of N2 followed by reactions with hydrocarbons. In order to understand the physicochemical mechanisms responsible for the evolution of Titan's atmosphere, photochemical models are built. The latter need constrains for vertical profiles of organic compounds from the high thermosphere down to the low stratosphere as well as photodissociation rates. Those profiles over the entire atmosphere can be retrieved from Cassini observations, in particular by limb sounding, coupling infrared and ultraviolet spectroscopy. However, …

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Development Of Chemometric Models And Calibration Transfer For Rapid Diesel And Jet Fuel Analysis Using Near Infrared Spectroscopy, Christopher Matthew Larkin Oct 2009

Development Of Chemometric Models And Calibration Transfer For Rapid Diesel And Jet Fuel Analysis Using Near Infrared Spectroscopy, Christopher Matthew Larkin

Chemistry & Biochemistry Theses & Dissertations

Fuel quality assurance and analysis, as it pertains to the United States armed forces, is crucial for maintaining operability and upholding safety regulations with respect to fuel class. Currently a great amount of effort, money and manpower are dedicated to this task as fuel analysis takes place in off-site laboratories where quality assessment and property determination is performed manually by highly qualified lab technicians. This presents the military with a logistics problem with respect to refueling, transport, and fuel storage as the typical tum-around time is 1-2 weeks. In this thesis it has been demonstrated that near-infrared spectroscopy, in conjunction …

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Hierarchical Subject Inter-Relations In Physical Chemistry, Carl W. David Sep 2009

Hierarchical Subject Inter-Relations In Physical Chemistry, Carl W. David

Chemistry Education Materials

Students mystified by the progression of topics in Physical Chemistry may gain insight into their path through the material if acquainted with the diagrams presented and discussed herein.

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Vuv Photostability Of Prebiotic Species, M. Schwell, Y. Bénilan, M.-C. Gazeau, N. Fray, A. Jolly, Et. Es-Sebbar, N. Champion, S. Leach, H. W Jochims, H. Baumgärtel, E. Rühl Sep 2009

Vuv Photostability Of Prebiotic Species, M. Schwell, Y. Bénilan, M.-C. Gazeau, N. Fray, A. Jolly, Et. Es-Sebbar, N. Champion, S. Leach, H. W Jochims, H. Baumgärtel, E. Rühl

Dr. Et-touhami Es-sebbar

No abstract provided.

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S.E.T.U.P. Experimental And Theoretical Simulations Useful For Planetology- Related Studies In The Frame Of A Program Of Titan’S Atmosphere Laboratory Simulations, M.-C. Gazeau, Et. Es-Sebbar, E. Arzoumanian, C. Romanzin, A. Jolly, S. Perrier, Y. Bénilan Sep 2009

S.E.T.U.P. Experimental And Theoretical Simulations Useful For Planetology- Related Studies In The Frame Of A Program Of Titan’S Atmosphere Laboratory Simulations, M.-C. Gazeau, Et. Es-Sebbar, E. Arzoumanian, C. Romanzin, A. Jolly, S. Perrier, Y. Bénilan

Dr. Et-touhami Es-sebbar

No abstract provided.

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Spectroscopic Investigation Of The Anatase-To-Rutile Transformation Of Sol-Gel Synthesised Tio2 Photocatalysts, Nicholas Nolan, Suresh Pillai, Michael Seery Sep 2009

Spectroscopic Investigation Of The Anatase-To-Rutile Transformation Of Sol-Gel Synthesised Tio2 Photocatalysts, Nicholas Nolan, Suresh Pillai, Michael Seery

Articles

Among the three major phases in titania, anatase is reported to be a better photocatalytically active phase. Anatase to rutile transformations, under normal conditions, usually occurs at a temperatue range of 600- 700 °C. Various chemical additives have previously been employed to extend the anatase transition to higher temperatures. Effect of employing various concentrations of formic acid and water on phase transition has systematically been studied by XRD, FTIR and Raman spectroscopy. A considerably higher anatase phase (41%) has been obtained at 800 ºC and 10% anatase composition is retained after annealing the materials at 900 ºC for the optimised …

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