Chemistry Commons^™

Nuclear Criticality Analyses Of Separations Processes For The Transmutation Fuel Cycle, William Culbreth, Pang Tao, Denis Beller

Separations Campaign (TRP)

The separation and partitioning of used commercial reactor fuel is a vital component of any reprocessing or transmutation strategy. To process the high actinide fuels required for a transmutation effort, the Chemical Technology Division (CMT) at Argonne National Laboratory (ANL) is developing a pyrochemical separations process. Currently, this work is being done via small experiments. While this is more than sufficient to develop the technologies required to process actinide-bearing fuels, it does not allow for the direct investigation of criticality concerns that would be present in larger systems. As the volume of waste to be treated increases, a higher probability …

Analysis Of Plastics In The Tyre Industry Using Fourier Transform Infrared Techniques, Differential Scanning Calorimetry And Softening Point Apparatus, Ching Ching Loh

Student Works (2000-2009)

The plastics in a tyre factory were investigated. The plastics were analysed by FTlR-transmission, FTI.R-ATR, softening point apparatus as well as a Differential Scanning Calorimeter. All the plastics were detected to be polyethene based with melting point range of 107 to 125°C. It was also observed that The FTIR transmission spectrum can be different from the FTIR-ATR spectrum. The FTIR-ATR spectrum gives a higher band intensity at longer wavelengths compared to the FTIR-Transmission spectrum. Interference fringes can be present in the FTlR transmission spectrum. In addition to the above, it was also found that the melting point of plastics obtained …

Formation Of Copper Dots In Copper Decoration Technique, Swee Yong Pung

Student Works (2000-2009)

Copper ions are dissolved from highly pure copper plate into the methanol during copper decoration process. As a result, copper concentration in methanol is increased with time. The copper concentration in methanol measured by ICP-OES is correlated well with the calculated value based on the magnitude of current and time during the process. Consequently, higher magnitude of current can be applied to build up copper concentration in methanol in shorter period. When copper ions are ejected in methanol, they are positively charged. They experience force from electric field and migrate towards oxide surface. Eventually, these copper ions will be discharged …

Nuclear Criticality Analyses Of Separations Processes For The Transmutation Fuel Cycle: Quaterly Report, William Culbreth, Pang Tao

Separations Campaign (TRP)

During the first quarter of the work, the tasks included training students in the use of Monte Carlo codes used in radiation transport studies and the assessment of neutron multiplication factors for specific problems outlined by ANL-East through Drs. Laidler and Vandegrift.

The proposal also included objectives for the first year of work on this project, as listed below. The work conducted in the first quarter of the project was in partial completion of these objectives.

• Train UNLV students in the use of SCALE and/or MCNP for the assessment of nuclear criticality.

• Assess neutron multiplication factor, k_{eff …}

Corrosion Of Steel In Sea-Bottom Mud Of Nothern China Sea Area, Gong-Yu Guo, Jing-Lei Zhang, Bao-Rong Hou, Fang-Ying Yang

Journal of Electrochemistry

Corrosion experiments of A₃, 16Mn, 20^# as well as ZCE36-225 steel were carriedout in southern Bohai sea and Qingdao sea areas. The sea-bottom mud in southern Bohai sea areais the sandy mud and that in Qingdao sea area is pure beach sand. In this experiment, the compareing test of two modes with electric connected and non-electric connected modes was carriedout. The experiment results showed that: 1) The corrosion rate of steel in sea-bottom mud has astrong relation with mud types. The corrosion rates of steels in pure beach sand are much higherthan those in sandy mud. 2) …

Electrosynthesis Of A New Electroactive Poly(2,2'-Diaminophenyloxydisulfide), Yu-Zhi Su, Yan-Wen Rao, Ye Yang, Mei-Bing Chen, Yin-Ling Qiu, Yong-Hua Zhang, Ke-Cheng Gong

Journal of Electrochemistry

A new electroactive poly (2,2' diaminophenyloxydisulfide) (PDAPD) was successfully synthesized from acetonitrile(AN)/tetrahydrofuran (THF) solutions containing the supporting electrolyte (LiClO₄) and the various kinds of acids (HCl, CF₃COOH, CCl₃COOH) on Pt electrode by consecutive cyclic voltammiry. The effects of the concentrations of supporting electrolyte (LiClO₄) and acid (HCl, CF₃COOH, CCl₃COOH) on electrodepositon of PDAPD film were investigated. The best experimental conditions for electrosynthesis of a highly electroactive conducting polymer film are that the concentrations are 0.1 mol/L and between 0.05 mol/L～0.5 mol/L,respectively for LiClO₄ and HCl.

Studies On The Anti-Corrosion Behavior Of Corrosion Inhibitor To The Ship Building Steel In Moist Air, Yong-Tao Zhao, Jian-Hua Wu, Jia Wang

Journal of Electrochemistry

The anti corrosion behavior of 907A steel, which were covered with thin inibitor layers in moist air, were simulated, The electrochemical measurements, including EIS method and the coulostatic method, were used to atmospheric corrosion monitor (ACM) under thin inhibitor layers to study the mechanism of rust preventiion. the results shown that the mechanism of inhibiting corrosion was different from the steel immersed in inhibitor solutin, the anodic reaction process under thin inhibitor layers had the advantage over that of cathodic for blocking the speed of corrosion. At the later stage of soaking, the blend feature due to the electrochemical process …

The Investigation Of Prepare Condition For Micropores Membranes From Poly(Vinylidene Fluoride), Xu-Mei Ren, Feng Wu, Ying Bai, Hang-Jun Li, Xue-Jie Huang

Journal of Electrochemistry

The micropores membranes from Poly (vinylidene fluoride) were prepared by the phase inversion process. The effects of the casting solution composition, exposure time prior to coagulation and temperature of the coagulation bath on properties of prepared membranes were investigated. For all prepared membranes an asymmetric structure, sometimes without a dense skin layer, was observed.

An Investigation Of Structural Properties Of Li-Al-Mixed Doped Spinels Materials Li 1+XAlYMn Z-YO4, Zi-Shan Zheng, Zi-Long Tang, Zhong-Tai Zhang, Wan-Ci Sheng

Journal of Electrochemistry

Al and Li elements were co-doped into host spinel lithium manganese oxide by a simple and economical preparation technology. There was an investigation of the influence of doped Al contents on the initial capacity and cycling performance of the materials. The investigation of the XRD patterns, the analysis of the SEM micrographs and the determination of IR spectroscopy showed that the particles of dopant materials are fine, narrowly distributed and well crystallized, and the bonds Mn-O are stronger than these of undoped materials. The resulted materials have a high initial capacity of 119 mAh/g and good cycling characterization. The capacity …

Studies On The Properties Of The Anodic Films Formed On Lead- Lanthanum And Lead-Samarium Alloys In Sulfuric Acid Solution, Hou-Tian Liu, Chun-Xuao Yang, Hai-Heng Liang, Jiong Yang, Wei-Fang Zhou

Journal of Electrochemistry

AC voltammetry, linear sweep voltammetry, and cyclic voltammetry were applied to study the anodic corrosion of Pb, Pb-1.0 at% La and Pb-1.0 at% Sm electrodes in 4.5 mol·dm^-3 H₂SO₄ solution (25 ℃). The experiment results show that samarium can inhibit the anodic corrosion of lead and decrease the impedance of anodic Pb(Ⅱ) film. Lanthanum can also decrease the impedance of the anodic Pb(Ⅱ)film, but the effect is smaller.

Analyses On Spm Images And Theoretical Investigations On Oxygen Vacancy Concentration Of Light-Induced Nanostructured Titania Super Hydrophilic Films, Ren-Jie Zeng, Zhong-Hua Lin, Zhi-Min Fang

Journal of Electrochemistry

A typical nanostructured titania super hydrophilic film was chosen for general char2 acterization employing a Scanning Probe Microscope (SPM) and an electrochemical measurement system. Following from the principles of the solid state chemistry and nanomechanics, intensive theoretical. analyses on the SPM images, the oxygen vacancy concentration sand the mechanism of the super hydrophilicity were made; further illuminationsona reactionequation of titania defect formation, a tentative universal surface physical mode for the wet-ability, a concept, amphiphobic-ity, and surface design were carried out after the author’ sprevious introduction and proposal in the end of 1999.

The Research Of Organic Electrolyte Solutions For Li-Ion Batteries, Quang-Chao Zhuang, Shan Wu, Wen-Yuan Liu, Zhao-Da Lu

Journal of Electrochemistry

The characteristics of organic electrolyte solutions and its influences on the ion conductivity are summarized. The chemistry and electrochemistry of organic electrolyte solutions and characteristics of ordinary organic solvents are introduced. Progresses in studies of organic electrolyte solutions such as electrolyte salts, organic solvents, additives in recent years are reviewed, current situation of the studies of organic electrolyte solutions were also discussed.

New Progress Of Intrinsic Conducting Polymers' Application, Wan Chen, Cheng-Hao Liang, Yang Xie

Journal of Electrochemistry

As a kind of functional polymer, the intrinsic conducting polymer has the special chemical, electrochemical and optical properties. So it has wide application such as batteries, electromagnetic wave shielding, electroluminescent etc. Recent development and the problems of the intrinsic conducting polymers' application were briefly reviewed in this paper.

Thermal Effects On The Measurement Of Photocurrent At Anodic Films On Silver Electrode, Yuan Gu, Zhi-Yu Jiang

Journal of Electrochemistry

The influence of heat on the photocurrent of Ag electrde in alkaline solution was investigated by measuring photocurrent, photothermal signal and thermal current under the irraiation of laser beams with the wavelengths of 488 nm and 532 nm. It was found the photocurrent atthe Ag₂O film was influenced by the temperature change at the electrode surface under the irradiation of light. During the electrochemical transfer between Ag, Ag₂O and AgO in the anodic filmthe surface temperature changed obviously due to the different absprptance of the surface subrstances.It was suggested by comparing the voltammograms, photocurrent curves and …

Study Of Hydrogen Diffusion Behavior In Hydrogen Storage Alloy Mlni3.75Co0.65Mn0.4Al0.2 With Potential Step Method, Xian-Xia Yuan, Nai-Xin Xu

Journal of Electrochemistry

Potential step method was employed to study the hydrogen diffusion behavior in hydrogen storage alloy MlNi_3.75 Co_0.65Mn_0.4Al_0.2 with various depth of discharge (DOD) at ambient temperature and with 50% DOD at various temperatures. It was found that hydrogen diffusion cofficient in the hydrogen storage alloy increaes with the increase in DOD at ambient temperature. and for the alloy with 50% DOD, the hydrogen diffusion coefficient increases with the increase in temperature and the activation energy for hydrogen diffusion in the alloy is 19.87 kJ/mol.

Research Progress On Proton Exchange Membranes Of Fuel Cells, Jing-Rong Yu, Dan-Min Xing, Fu-Qiang Liu, Jian-Guo Liu, Bao-Lian Yi

Journal of Electrochemistry

The proton exchange membrane fuel cells (PEMFC) use proton exchange membranes(PEM) as their electrolytes. The performance of the PEMFC is strongly dependent on the characteristics of the PEM. In this paper, the requirements of the PEM utilized in the PEMFC were analyzed. The per-fluorinated, partially fluorinated and non-fluorinated PEM were introduced respectively. The structures, preparation, properties of the various types of PEM and their applications in the PEMFC were also discussed in detail.

The Influence Of Synthesis Conditions On The Electrochemical Properties Of Spinel Limn2O4, Jun-Feng Xu, Zhi-Yu Jiang

Journal of Electrochemistry

The electrochemical properties of spine LiMn₂O₄ synthesized via a solid state reaction were investigated. Electrolysis MnO₂(EMD), Li₂CO₃ ,LiOH and LiNO₃ were used as the initial materials. It was found that the electrochemical properties of LiMn₂O₄ were strongly influenced by the synthesis conditions. The LiMn₂O₄ sample sprepared via the reactionof EMD and LiNO₃ showed the best properties for a lithiumion intercalation reaction. The procedure includes two steps:pretreatment at 280 ℃ for 6 hours to initiate the permeation of melting LiNO₃ into the microporesof EMD …

Adsorption And Oxidation Of Methanol On Pt And Sb, S Modified Pt Electrodes Using Cyclic Voltammetry And Eqcm, Guo-Liang Chen, Sheng-Pei Chen, Heng Lin, Xing-Hong Zheng, Shi-Gang Sun

Journal of Electrochemistry

The processes of adsorption and oxidation of methanol on Pt, Pt/Sb ad and Pt/S ad electrodes were studied by using cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results demonstrated that the oxidation of methanol depends strongly on oxidation states of electrode surface. Sb adatoms on Pt surface can adsorb oxygen at relatively low potentials, and exhibit catalytic effects for methanol oxidation. In contrast to Pt electrodes, the oxidation peak potential of methanol in this case negatively shifted to about 130 mV. In a contrary, the oxidation of S_ad atoms consumes oxygen species of Pt electrode surface. As …

Study On Electrochemical Behavior Of Copper In Nh3 ·H2O Solution Medium Including K3[Fe(Cn)6] During Cmp, Yue-Hua Hu, Han-Wei He, Ke-Long Huang

Journal of Electrochemistry

Influence of medium pH value and passivator concentrations on the copper passivation and CMP process were studied by electrochemical measurement technologies, relations of the film thickness and tightness with polishing process and polishing rates were investigated. Electrochemical variables influencing polishing process and rates were found out. Electochemical mechanism of polishing processes were explained by corrosion potential and corrosion current density. A recipe of K₃[Fe(CN)₆] as passivator and nano sized γ-Al₂O₃ as abrasives in medium of NH₃·H₂O solution was confirmed reasonable. It is shown that the conditions of polishing process …

Study On The Anticorrosion Of Ld-2 Compound Inhibitor On Reinforcing Steel In Seawater, Rong-Gui Du, Zhou-Cheng Wang, Ruo-Shuang Huang, Rong-Gang Hu, Bing Zhao, Jian-Guang Tan, Chang-Jian Lin

Journal of Electrochemistry

The effect of LD-2 compound inhibitor developed in our laboratory on its anticorrosion action on the reinforcing steel in concrete immersed in seawater was shown in this paper. The corrosion behavior of the reinforcing steel in seawater was studied using electrochemical techniquesand immersion tests. The polarization curve of the reinforcing steel immersed in seawater showedthe free corrosion potential of the steel increased by 0. 220 V (vs. SCE), and the corrosion current decreased by two orders of magnitude by adding 25 g⋅L^-1 compound inhibitor to the seawater. The potentiodynamic anodic polarization curve of reinforcing steel in the seawater with …

Environment-Induced Degradation And Crack-Growth Studies Of Candidate Target Materials: Aaa Task-4 Quarterly (September 1 – November 30, 2001) Report, Ajit K. Roy, Brendan O'Toole

Transmutation Sciences Materials (TRP)

The primary objective of this task is to evaluate the effect of hydrogen on environment-assisted cracking of candidate materials for applications in spallation-neutron-target (SNT) systems such as accelerator production of tritium (APT) and accelerator transmutation of waste (ATW). The materials selected for evaluation and characterization are martensitic stainless steels including HT- 9, EP 823 and 422. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement (HE) of these alloys will be evaluated in environments of interest using tensile specimens under constant load and slow-strain-rate (SSR) conditions. The extent and morphology of cracking of these alloys will further be evaluated …

Analysis Of Corrosion Of Steel By Lead Bismuth Eutectic, John Farley, Dale L. Perry

Transmutation Sciences Materials (TRP)

We examined stainless samples that were exposed to LBE in experiments conducted by the Russians, under contract to Los Alamos. We examined both corroded and uncorroded samples using the Scanning Electron Microscope (SEM), the Energy Dispersive X-Ray (EDAX) Spectroscopy, and the X-ray Photoelectron Spectrometer (XPS). We found that the surface of the corroded sample is covered by oxygen-containing compounds, presumably mostly iron oxide. In samples exposed for shorter times or lower temperatures, we found that some areas were covered by an oxide layer, and some areas was uncovered. We found that the level of Cr in the uncovered area is …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics: Quarterly Progress Report August 16,2001- November 15, 2001, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the AAA proposed application.

Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with very limited density. The transport of oxygen and corrosion products, their interaction and variation of corrosion/precipitation along the flow are not well understood.

The first subtask of this project involves using a …

A Dipolar Coupling Based Strategy For Simultaneous Resonance Assignment And Structure Determination Of Protein Backbones, Fang Tian, Homayoun Valafar, James H. Prestegard

Faculty Publications

A new approach for simultaneous protein backbone resonance assignment and structure determination by NMR is introduced. This approach relies on recent advances in high-resolution NMR spectroscopy that allow observation of anisotropic interactions, such as dipolar couplings, from proteins partially aligned in field ordered media. Residual dipolar couplings are used for both geometric information and a filter in the assembly of residues in a sequential manner. Experimental data were collected in less than one week on a small redox protein, rubredoxin, that was 15N enriched but not enriched above 1% natural abundance in 13C. Given the acceleration possible with partial 13C …

Highly Plasma Etch-Resistant Photoresist Composition Containing A Photosensitive Polymeric Titania Precursor, Tony D. Flaim, Douglas J. Guerrero, Michelle R. Fowler, William Joseph James, Vladimir Petrovsky, Harlan U. Anderson

Chemistry Faculty Research & Creative Works

A composition is derived from an addition polymerizable organotitanium polymer which upon exposure to an oxygen plasma or baking in air, is converted to titanium dioxide (titania) or is converted to a mixed, titanium-containing metal oxide. The metal oxide formed in situ imparts etch- resistant action to a patterned photoresist layer. The composition may also be directly deposited and patterned into permanent metal oxide device features by a photolithographic process.

Characterization And Electrochemical Investigation Of Boron-Doped Mesocarbon Microbeads Anode Materials For Lithium-Ion Battery, Mao-Hui Chen, Guo-Tao Wu, Guang-Ming Zhu, Jin-Kua You, Zu-Geng Lin

Journal of Electrochemistry

The anodic performances of boron doped and undoped mesocarbon microbeads(MCMBs) were comparatively studied and the structures were characterized by XPS, SEM, XRD and electrochemical measurements. It was found that boron doping samples greatly increased the degree of graphitization and the crystallite size, leading to quite different morphology. Electrochemical discharge/charge cycle tests indicate that lithium intercalation occurred at a little higher potential for the boron doped MCMBs, being attended by greater irreversible capacity loss.

Microstructure And Electrochemical Properties Of The Melt-Spinning Zr0.9Ti0.1(Ni, Co, Mn, V)2.1 Alloy, Ming-Fen Wen, Yu-Chun Zhai, Lian Chen, Min Tong, Hua Zhen, Rong-Jun Ma

Journal of Electrochemistry

The microstructure and electrochemical properties of Zr_0.9Ti_0.1(Ni,Co,Mn,V)_2.1 alloys prepared by both the melt-spinning method and the conventional induction melting were investigated. XRD studies show that Zr_0.9Ti _0.1(Ni,Co,Mn,V)_2.1 alloys at as-cast, melt-spinning and annealing are all face center cubic structure with C₁₅ laves phase, the higher the melt-spinning rate, the more the amorphous content. The electrochemical measurements show that melt-spinning alloys have better active behavior, low discharge capacity (< 280 mAh/g); but after annealed, the alloys are activated completely with 30 cycles, the capacities about 340 mAh/g are higher than those of as-cast and melt-spinning alloys; the annealec alloys have a better cycle stability than that of as-cast alloy, and the higher the melt-spinning rate is, the more stable the alloy becomes; at 300 mAh/g current density, the capacity of annealed 40 m/s alloy is up to 85% of the maximum capacity after 800 cycles, the capacity decay rate is about 6.9%.

Charge/Discharge Characteristics And Structural Changing Of Spherical β-Ni(Oh)2 Prepared From Different Nickel Salt, Shu-Ting Yang, Yan-Hong Yin, Hong-Jun Chen, Jun-Hua Jia, Ming-Chum Zhang, Li Ding

Journal of Electrochemistry

Spherical β-Ni(OH)₂ was prepared from different nickel salt by homogeneous complexing precipitation method. Its charge/discharge and cyclic voltammetry properties were studied. The authors found that there are many differences in the electrochemical properties of the prepared Ni(OH)₂.The specific capacity, cycling life and the discharging plateau of the material prepared from NiSO₄ were superior to those of the material prepared from Ni(NO₃)₂. The reasons of the differences were analyzed by XRD and FTIR measurements, which will become abasis for the selection of raw materials.

In Situ Ftir Reflection Spectroscopy Of Bioelectrode, Sa-Ying Dong, Guang-Yu Zhao, Yuzhu Gao, Guang-Zhang Chen, Ming-Xiang Lv

Journal of Electrochemistry

In situ FTIR reflection spectroscopy was used to study mediated enzyme electrode and immunoelectrode. We determined and analyzed IR characteristic spectra of GOD and glucose by the use of potential difference spectra and single beam subtractive spectra. At last, we explored the IR absorption characters of enzyme-immunoelectrode.

The Influence Of Membrane Resistance On The Electrochemical Behavior Of Gold Electrode Modified By Self-Assembled Monolayer, Xiao-Li Cui, Zhi-Yu Jiang

Journal of Electrochemistry

The electrochemical behavior of gold electrode modified by hexadecanethiol self-assembled monolayer (SAM) in the solution of Fe(CN)₆^3-/Fe(CN)₆^4- was investigated by cyclic voltammetry and ac impedance spectroscopy. The pinhole-free SAM-modified gold electrode has excellent blocking properties to the interfacial electron transfer from redox couple in solution to the substrate. The current increased exponentially with the overpotential at the high potential region. A good linear relationship between ln(I/η) and η_1/2 was observed. A model system Au/SAM/Hg was constructed and its I～V curve was measured. Similar phenomena were observed. There was also a linear relationship between ln(I/V) …