Physical Sciences and Mathematics Commons^™

Squeeze-Out Of Nuclear Matter In Au+Au Collisions, M. B. Tsang, P. Danielewicz, W. C. Hsi, M. Huang, W. G. Lynch, D. R. Bowman, C. K. Gelbke, M. A. Lisa, Graham F. Peaslee, R. J. Charity, L. G. Sobotka, M. L. Begemann-Blaich, F. Cosmo, A. Ferrero, J. Hubele, G. Imme, I. Iori, J. Kempter, G. J. Kunde, W. D. Kunze, V. Lindenstruth, U. Lynen, M. Mang, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilive, J. Pochodzalla, G. Raciti, F. Rosenberger, T. Rubehn, H. Sann, R. Scardaoni, A. Schüttauf, C. Schwarz, W. Seidel, V. Serfling

Faculty Publications

Emission of charged particles from a compressed reaction zone is studied for Au197+197Au collisions at E/A=100, 250, and 400 MeV. Using a modified coalescence invariant weighting, squeeze-out ratios are determined and compared to predictions of cascade and BUU transport-model calculations.

Squeeze-Out Of Nuclear Matter In Au + Au Collisions, M. B. Tsang, P. Danielewicz, W. C. Hsi, M. Huang, W. G. Lynch, D. R. Bowman, C. K. Gelbke, M. A. Lisa, Graham F. Peaslee, R. J. Charity, L. G. Sobotka, M. L. Begemann-Blaich, F. Cosmo, A. Ferrero, J. Hubele, G. Imme, I. Iori, J. Kempter, P. Kruetz, G. J. Kunde, W. D. Kunze, V. Lindenstruth, U. Lynen, M. Mang, A. Moroni, W. F.J. Müller, M. Neumann, B. Ocker, C. A. Ogilvie, J. Pochodzalla, G. Raciti, F. Rosenberger, T. Rubehn, H. Sann, R. Scardaoni, A. Schüttauf, C. Schwarz, W. Seidel

Faculty Publications

Emission of charged particles from a compressed reaction zone is studied for Au197+197Au collisions at E/A=100, 250, and 400 MeV. Using a modified coalescence invariant weighting, squeeze-out ratios are determined and compared to predictions of cascade and BUU transport-model calculations.

A Spin Reorientation In Pr₂Fe₁₇D₃ As Revealed By Mössbauer Spectroscopy, Fernande Grandjean, Dimitri Hautot, Gary J. Long, Olivier Isnard, Salvatore Miraglia, Daniel Fruchart

Chemistry Faculty Research & Creative Works

The Mössbauer effect spectra of Pr₂Fe₁₇D₃, which have been measured between 85 and 295 K, indicate the presence of a spin reorientation of the iron magnetic moments at 105±5 K. At this magnetic transition a large increase of ~50 kOe in the 6c iron magnetic hyperfine field and abrupt changes in all of the remaining hyperfine fields are observed. A study of the changes in the quadrupole shifts at the transition indicates that this spin reorientation takes place within the basal plane of this rhombohedral compound. As expected, the temperature dependence of the isomer …

Dynamics And Conformation Of Polymer Chains In A Porous Medium, Grace M. Foo, R.B. Pandey, D. Stauffer

Faculty Publications

No abstract provided.

The Effects Of Free Fatty Acids And Tocopherol On Membrane Order And Antioxidant Activity, Gina Michelle Pineda

Honors Theses

No abstract provided.

Neutron Diffraction And Mössbauer Spectral Study Of The Nd₂Fe₁₆Ticₓ Solid Solutions, Gaya Kanishka Marasinghe, Peter C. Ezekwenna, William Joseph James, Gary J. Long, Oran Allan Pringle, Zhongbo Hu, William B. Yelon, Fernande Grandjean

Chemistry Faculty Research & Creative Works

Three samples of , with x equal to 0.0, 0.3, and 2.8, with the Th₂Zn₁₇-type rhombohedral structure, have been studied by powder x-ray and neutron diffraction, magnetic measurements, and Mössbauer spectroscopy. Nd₂Fe₁₆Ti and Nd₂Fe₁₆TiC_0.3 were synthesized by induction melting stoichiometric amounts of the constituent elements, whereas Nd₂Fe₁₆TiC_2.8 was synthesized by methane-derived gas phase insertion of carbon into finely ground Nd₂Fe₁₆Ti at 600 K. The neutron diffraction determined titanium site occupancies are similar in both Nd₂Fe_{16 …}

Petrochemical Analysis By Remote Fiber-Optic Raman Spectroscopy And Partial Least Squares Regression Analysis, Philip Edmund Flecher Jr.

Chemistry & Biochemistry Theses & Dissertations

A dispersive Raman system with charge coupled device (CCD) detection, distributed Bragg reflector (DBR) diode laser excitation, and a fiber optic probe has been developed for the rapid analysis of petrochemicals and fuels. Initially, mock petroleum fuels with analyte concentrations from 1.S - 16% were prepared and analyzed with the system. The inability of the original index guided diode laser to maintain a constant frequency during the mock petroleum analysis was a recurrent problem. The DBR laser was subsequently shown to have stability superior to index guided lasers, and was used in the remainder of the research.

Real gasoline samples …

Statistical Multifragmentation In Central Au+Au Collisions At 35 Mev/U, M. D'Agostino, A. S. Botvina, P. M. Milazzo, M. Bruno, G. J. Kunde, D. R. Bowman, L. Celano, N. Colonna, J. D. Dinius, A. Ferrero, M. L. Fiandri, C. K. Gelbke, T. Glasmacher, F. Gramegna, D. O. Handzy, D. Horn, W. C. Hsi, M. Huang, I. Iori, M. A. Lisa, W. G. Lynch, L. Manduci, G. V. Margagliotti, P. F. Mastinu, I. N. Mishustin, C. P. Montoya, A. Moroni, Graham F. Peaslee, F. Petruzzelli, L. Phair, R. Rui, C. Schwarz, M. B. Tsang, G. Vannini, C. Williams

Faculty Publications

Multifragment disintegrations, measured for central Au + Au collisions at , are analyzed with the Statistical Multifragmentation Model. Charge distributions, mean fragment energies, and two-fragment correlation functions are well reproduced by the statistical breakup of a large, diluted and thermalized system slightly above the multifragmentation threshold.

Evaluation Of The Concentration And Enantiomeric Purity Of Selected Free Amino Acids In Fermented Malt Beverages (Beers), K. Helen Ekborg-Ott, Daniel W. Armstrong

Chemistry Faculty Research & Creative Works

Even though amino acids are important trace components in the brewing of beers, they have not been extensively evaluated in these beverages. Studies involving the enantiomeric composition of these amino acids are even less prevalent. A brief summary of the brewing process for malt beverages is given. The total concentration and enantiomeric composition of three amino acids (leucine, phenylalanine, and proline) were determined in 25 different beers. Proline tended to have the highest average absolute concentration and the lowest percentage of the D-enantiomer in most samples. In some cases the relative amounts of D-phenylalanine and D-leucine exceeded 10% of the …

Computation Of Electron Affinities Of O And F Atoms, And Energy Profile Of F-H2 Reaction By Density Functional Theory And Ab Initio Methods, Branko S. Jursic

Chemistry Faculty Publications

The validity of hybrid and nonlocal DFT methods are tested on examples of systems which are difficult to model by way of quantum chemistry techniques. The electron affinities for the oxygen and fluorine atoms were calculated. The exothermicity, the barrier for the fluorine atom reaction with the hydrogen molecule, and the energy of the H–F bond and its distance were computed with DFT methods, as well as, with ROHF, MPn, and QCISD ~T! ab initio methods. The computations were performed by using various basis sets, with 6-311 11G(3d f ,3pd as the largest. The obtained results are compared …

Thermal Nucleation And Cavitation In Helium-3 Fluids, Xiao Cheng Zeng, D.W. Oxtoby, E. Cheng

Xiao Cheng Zeng Publications

We have investigated droplet nucleation and bubble cavitation in the quantum fluid helium-3 based on a nonlocal density-functional approach. A marked effect of droplet (or bubble) curvature on the rate of droplet nucleation or cavitation has been found. Without considering this curvature effect (as in the classical theory of nucleation) the droplet nucleation rate for helium-3 could be underestimated (i.e., near 1 K) or overestimated (i.e., near 2.5 K) by orders of magnitude, respectively; for bubble cavitation, the rate could be underestimated by more than twenty orders of magnitude (near 1 K).

One-Pot Preparation Of 1,3-Dihydro-1- (Trifluoromethyl)Isobenzofuran-1-Ol Derivatives From 1,2-Dibromobenzene, Daniel Becker, Hui Li, Daniel L. Flynn

Chemistry: Faculty Publications and Other Works

A one-pot method for the preparation of 1,3-dihydro-1-(trifluoromethyl)isobenzofuran-1-ol derivatives 5from 1,2-dibromobenzene is described

A Magnetic Neutron Diffraction, And Mössbauer Spectral Study Of The Ce₂Fe₁₇₋ₓalₓ Solid Solutions, Sanjay R. Mishra, Gary J. Long, Oran Allan Pringle, D. P. Middleton, Zhongbo Hu, William B. Yelon, Fernande Grandjean, K. H. J. Buschow

Chemistry Faculty Research & Creative Works

The magnetic properties of a series of Ce₂Fe_17-xAl_x solid solutions with x equal to 0.00, 0.88, 2.06, 2.81, 3.98, 5.15, 6.08, 7.21, 8.20, 9.08, 9.84, and 10.62 have been studied by magnetic measurements, neutron diffraction, and Mössbauer spectroscopy. The compounds crystallize in the rhombohedral Th₂Zn₁₇-type structure. Magnetization studies indicate that the Curie temperature increases uniformly from 238 K for Ce₂Fe₁₇ to 384 K for Ce₂Fe₁₄Al₃ and then decreases at higher aluminum content. Powder neutron diffraction results, obtained at 295 K, indicate that aluminum …

On The Optimization Of A Dc Arcjet Diamond Chemical Vapor Deposition Reactor, Scott Reeve, Wayne Weimer, David Dandy

Scott Reeve

No abstract provided.

An Indirect Electrochemical Oxidation Of Toluene─Catalytic Effects Of Ag(Ⅰ) On Mn(Ⅱ)/Mn(Ⅲ) Couple Transition At Pt Electrode, Zhonghua Wang, Yunan Qu, Xingguo Yan, Qngmin Hua, Guacai Chen, Zhongquan Wang

Journal of Electrochemistry

The Catalytic effects of Ag(Ⅰ) on toluene oxidation by Mn(Ⅲ) as well as the anodic generation of Mn(Ⅲ) were investigated. The rates of toluene oxidation were first order with respect to both Ag(Ⅰ) and Mn(Ⅲ). Ag(Ⅱ) formed on the surface of the platinum anode when Ag(Ⅰ) was present in the anolyte, which catalyic the Mn(Ⅱ) to Mn(Ⅲ) in solution.

Kinetic Behavior Of The Pt/Ysz Solid Electrolyte Interface Exposed To O_2+He Mixture, Yi Jiang, Wenzhao Li, Lixin Cao, Jingwang Yan

Journal of Electrochemistry

Electrochemical behavior of the Pt/YSZ solid electrolyre interface has been investigated by cyclic voltammetry and linear potential sweep technique. It was found that the electrochemical adsorption of oxygen on the Pt surface follows the Temkin adsorption model. The amount of oxygen species increases logarithmically with time. Two oxygen species are electrochemically formed on the Pt surface. One is atomically adsorbed, the other probably subsurface oxygen or Pt oxide. The electrochemical reduction of adsorbed oxygen is kinetically irreverable. The cathodic peak potential is affected both by the potential sean rate and the amount of oxygen ahorbed on the surface. Kinetic parameters, …

The Inhibition Of Amphipathic S- And N-Containing Compounds On Carbon Steel Corrosion, Wei Xing, Yibin Shan, Du Guo, Tianhog Lu, Shiquan Xi

Journal of Electrochemistry

Ordered monolayers of S- and N-containing amphipathic corrosion inhibitors were depoitod onto the surfaces of carbon steel electrode with super-molecular assembly technique. The effect of molecular aggregation of monolayers on carbon steel corrosion in 0. 05 mol dl￣(-3)H_2SO_4 and the mechanisms of these inhibitors were discussed in details. It was found that the transport of hydrated hydrogen ion to the surface of steel depends strongly on the inhibitor molecular aggregation in the monolayers.

Electrochemical Studies On Corroding Metallic Electrodes In Frequency Domain, Chu' Nan Cao

Journal of Electrochemistry

The electrochemical studies on corroding metallic electrodes carried out in the State Key Laberatory for Corrosion and Protection are reviewed briefly: (1) General equations of faradaic admittance under potential-control condition were derived based on the stabillity conditions of steady processes. The faradaic admittance at mixed potential then was deduced based on these equations and the electrochemical impedance spectroscopy (EIS) at corrosion potentials in the solutions containing interface inhibitors was diseussed by application of the thecetical results obtained. (2) The spectral power density (SPD) curves for electrochemical noise (EN) during the initial stagu of pitting corrosion were observed for iron and …

Effects Of Ph,Ligand Cn-,Metallic Ions Hg￣(+2),Cd￣(+2) And Pb￣(2+) On Electroactivity Of Cytochrome C, Jin Luo, Lingling Wu, Jintain Wu, Shaohua Huang, Zhonghua Lin

Journal of Electrochemistry

The effects of pH, ligtlnd CN￣-,metallic ions,Hg￣(+2), Cd￣(+2) and Pb￣(2+) on electroactivity of cytochrome c have been studied with cyclic voltammetry and UV/Vis spectroseopy.In the phosphate buffer solution containing 5 mg/mL cytochrome c, cytochrome c is electroactive at a glod electrode with suitable pretreatment if the pH value is equal to 7.0, but it is electroinactive at the gold electrode if the pH value is equal to 2. 0 or 10.0. The existence of CN- ions in the solution would cause deactivation of cytochrome c in the bulk sulurion, and would not affect the electroactivity of cytochrome c adsorbed on …

Applicadons Of Laser In Electrochemistry(Ⅰ), Rin Ren, Zhongqun Tian

Journal of Electrochemistry

This paper is the first part of a comprehensive review of laser applied in electrochemistry. At first, it briefly introduces the advantages, history and exporimental setup of laser electrochamistry. Then it reviews laser applications in electrochemical deposition, polymerization,etching, polishing, corrosion, adsorption/desorption and reactions as well as photoelectrochemical switching and storage.

Determination Of Transport Number Of The Modified Liclo_4- (Peo)_(20) Polymer Electrolyte, Ruqi Zhou, Qngguo Liu, Weihua Qiu, Yun Zhang, Yuee Zhao

Journal of Electrochemistry

In this work a combination method of A. C. Impedance and chronoamperometry was used to determine the lithium ion transport number of LiClO_4·(PEO)_(20)·(PC)_(12)·(EC)_(12) polymer electrolyte. It is known that lithium is thermodynamically unstable in non-aqueous or polymer electrolytes, leading to the formtion of a film on lithium surface, called as solid electrolyte interphase (SEI). The presence of SEI layer will greatly influence the experimental result of lithium ion transport number. The new method avoid the effect of SEI layer, and can give correct transport number of lithium ion in the electrolyte of DCIO_4·(PED)_(20)·(PC)_(12)·(EC)_(12). The exporimental result indicates that the conducrivity …

Hydrogen Evolution Reaction On Nanocrystalline Co-Mo/Ni Composite-Coated Electrodes, Weizeng Yu, Jie Ma, Yiming Chu, Huizhe Zhu, Hongjie Wang, Shuncheng Liu

Journal of Electrochemistry

The electrochemical behaviours of the hydrogen evolution reaction(HER) at electrodes prepared by composite coating of nanocrytstalline Co-Mo alloy particles formed by ball milling on nickel base has been sludied by using sleady-state polarization and ac impedance techiu ques.The microstructure and the size of the nanocrystals of Co- Mo alloy and the morphology of the composite-coating surface of the electrodes are measured by XRD, TEM and SEM. Results show that the nanocrystalline Co-Mo alloys prepared by high energy ball milling has high electrocatalytic activity for HER. The electrocatalytic activity for the HER is enhanced and the energy of activation for HER …

Electrochemical Ploymerization Of Aniline In The Alkaline Solution And Properties Of Polymer, Shaolin Mu, Jinqing Kan, Aiguang Zhang

Journal of Electrochemistry

A deep yellow polyaniline was formed at the anodic electrode during electrochemical oxidation of aniline in the alkaline solution.The peak of oxidation potential for aniline in the alkaline solution was 0. 7 V (vs.Ag/AgCl with a saturated KCl solution),which is about 0. 3V less than that in the acidic solution.The results from rotating ring-disk electrode experiment show that two soluble intermediates were generated during electrochemical oxidation of aniline.The colour of the polymer in the alkaline solution is independent of applied potential and pH values.An adsorption peak was observed in the UV region at 500 nm for the polymer.The polymer has …

Preparation Techique Of Foamed Nickel By Electrodeposition, Xihua He, Ronghui Hu, Hanxi Yang, Zhengzhong Zuo

Journal of Electrochemistry

This paper describes the preparation technique and operation conditions for manufacturing foamed nickel by chemilcal pretreament, electrodeposition and heat treatment. The foamed nickel made in this method showed high porosity, uniformity and considerable strength and tenacity,applicable for various secondary battery electrodes.

Development Of The High Capacity Sintered Type Nickel Positive Electrode, Guohua Yu, Shijie Zhang, Xiaolin Wang, Jingqi Wei

Journal of Electrochemistry

By improving the design and technologies of the sintered type nickel oxide positive electrode for the NiMH batteries, We do our best to increase the sinter volume and porosity,the amount of the active materals and their utilization, so we have fabricated the high capacity sintered typo nickel electrodes fitting for the NiMH battreies. The sfecitic capacity of the lot produced electrodes is up to 550 mA/cm￣3.

Study Of The Calcium-Thionyl Chloride Cells, Baohong Zhang, Meng Chen, Yingdong Wang, Dongsheng Xu

Journal of Electrochemistry

The properties of CaCl_2 SEI covered on the ca electrode surface in thionyl chloride, the influence of various salts in thionyl chloride on the porformance of the Ca anede and carbon cathode, and the function of the additive CuCl_2 and CuBr_2 to cathode in the improvement of the cathode performance were studied by AC impedance, constant current discharge, and SEM. As a result,the Ca-SOCl_2 cell was able to discharge at 50 mA·cm￣(-2)and the capacity reached 17.5 mAh ·cm￣(-2).

A Study On Performance Of Electroless Nickel Coatings Containing Low Phsphorus, Huilin Guo

Journal of Electrochemistry

The low phosphorus coatings(LP) had superior corrosion resistence to that of high phosphorus(HP) in alkaline and neutral NaCl sulutions. The microhardness of the coatings increaed from 454 Hv to 890 Hv when they were heated at 350℃ for one hour. Two exothermic peaks were observed at 341. 6℃and 406. 2℃, which respectively corresponded to form the new phases Ni_5P_2 and Ni_3P in the differential thermal analysis. The atomic structure of as-deposited coatings in the terms of X-ray diffraction had confirmed that the coatings coasisted of extremely fine crystallites.

Research On Molten Carbnate Fuel Cell, Naichao Li, Baolian Yi, Lianying Kong, Enjun Zhang, Huaxin Lin, Tianxi Qu, Yingcai Cheng

Journal of Electrochemistry

Cold-roll-milling has been evaluated as a technique for preparing porous LiAlO_2 matrices for use as a molten carbonate fuel cell electrolyte matrix. This technique produces reliable electrolyte structures with the following characteristics and advantages: ease of handling, uniform thickness, using nontoxic inorganic solvents, controlled pore size distribution, and ability to be impregnated with the alkali carbonate without fracrure.The Molren Carbnatod Fuel Cell(MCFC) was assembled from sintered Ni electrodes and LiAlO_2 electrolyte matrix, the electrode area is 28 cm￣2, the effect of operating conditions on cell performance was tested, it was found that the cell performance changed little with many times …

The Electrochemical Behavior Of C￣(60)-Chemically Modified Poly(N-Vinylcarhzole)In 1 Mol/L Liclo_4-Thf Solutions, Yu Chen, Zuen Huang, Ruifang Cai, Fupin Zhang

Journal of Electrochemistry

The electrochemical behavior of C￣(60)-PNVC copolymer in 1 mol/L LiClO_4-THF solutions has been studied by cyclic voltammetry.The results demonstrated that there are considerable differences of electronic structure between PNVC (Poly (N-vinylcarbazole )) and C￣(60)-PNVC copolymer, this being consistent with the ESR results and the oxidstion-reduction activarion of pure PNVC by C￣(60)-chemical modification. In the potential region,1.3V～-3.5V,five steps,0. 90V/0.60V,0.20V/0.00V,-1.05V/-1.30 V,-1.25V/-1.75 V,-2.00V/-2.50V, of oxidation/reduction proceases were indicated in the cyclic voltammetry for pure PNVC,whereas seven steps,0.20V/0.20V,-0.30V/-0.50 V,-0. 60V/-0.60 V,-0.80V/-1. 10 V,-1.95V/-2. 10 V,-2. 50 V/-2. 70 V,-3. 00V/-3. 00 V, of oxidation/reduction processes for the C￣(60)-PNVC copolymer were observed under the idenrical …

Study On The Manufacture Of Pt/C Gas-Diffusion Electrodes, Yonglin Ma

Journal of Electrochemistry

The various methods of manufacturing gas-diffusion electrodes are reviewed and a new method of preparing the Pt/C electrocatalyst and the gas-diffusion electrodes is explored in this paper. The electrochemical performance of resulting electrodes in concentrated phosphoric acid for oxygen reduction at 150℃ are compared with the commercial electrode which purched from Giner Inc. (U. S. A). The results show that the performance of the Pt/C electrodes which manufactured by the method in this paper has been greatly improved. Therefor, a fuel cell using such electrodes has high industrial value.