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Activated Carbon Produced From Agricultural Residues, Daniel W. Armstrong, V. J. Flanigan, William Joseph James, Jui-Lung Li, Kimber L. Rundlett

Chemistry Faculty Research & Creative Works

A process for producing activated carbon from agricultural residues by heating the residues to a temperature in the range of about 250° C. to about 550° C. to volatilize organic compounds in the residues and to carbonize the residues and further heating to activate the carbonized residues. Activated carbon produced from agricultural residues.

Study Of Localized Corrosion Of Metals By Using The Electrochemical Techniques With Spatial Resolution, Chang-Jian Lin, Xiang-Dong Zhuo, Zu-De Feng, Rong-Gui Du, Zhao-Wu Tian

Journal of Electrochemistry

The electrochemical inhomogeneities at interface of metal/solution play an important and often controlling role in localized corrosion of metals. The traditional electrochemical techniques involving potential, current density or ac impedance measurements over bulk specimens can only provide average and general information of the interface. Thus, the development of in situ imaging techniques is essential for further characterizing electrochemical inhomogeneities at the metal/solution interface of localized corrosion system. The electrochemical techniques with spatial resolution,including scanning single micro electrode, scanning double micro electrodse and scanning micro chemical probes are reviewed. The effects of electrochemical inhomogeneities on the corrosion behavior, and the mechanism …

Electrochemical Surface Characterization Of Titanium Alloy(Ti-6al-4v), Jian-Zhong Chen, Qing-Liang Gao, Zhong-Yi Wang, Wen-Jing Xue

Journal of Electrochemistry

With its low density and high strength ratio, titanium alloy(Ti₆Al₄V) has become one of the most important materials both in the fields of aerospace and biomedical assays. Recently, titanium alloy was used as the implantation materials in human body because of its biocompatibility. The elecrochemical impedance techniques were then used to investigate the corrosion behavior of this material in hydrochloride and sulfuric acid solutions. A comparison between impedance spectra and anodic polarization over the correlated range of applied voltage confirms that AC impedance data can be used as a powerful tool for surface characterization of titanium …

Study On The Mechanism Of Ni/Zro2 Composite Electrodeposition, Qun-Jia Peng, Dao-Bin Mu, Ju-Sheng Ma, Xiang-Yun Tang

Journal of Electrochemistry

The effects of cathodic current density and amount of particle dispersion in solution on the codeposition of Ni/ZrO₂ composite in Watts bath were studied, and the machanism of the composite electrodeposition was investigated. The study shows that the composite electrodeposition is controlled by the transfer of particles to the cathode when the dispersion amount is small, causing the decrease of the codeposition with the increase of current density. With large amount dispersion, the composite electrodeposition is first controlled by the strong adsorption of particles on the cathode at low current density, resulting in the increase of the codeposition with …

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

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.

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 …

Study On Steel Corrosion In Simulated Biofilm Environment In Seawater, Qing-Fei Wang, Jing Sui, Run-Xi Su, De-Ying Kong, Shi-Zhe Song

Journal of Electrochemistry

Biofilm is one of the main factors that influence metal corrosion in seawater environment. According to the structure and property of biofilm, a natural biopolymeric gel, calcium alginate(an extracellular biopolymer containing carboxylate functional groups) can deposite on metal surfaces to form films. Corrosion behavior of alloyed steel E2, 10CrMoAl and 18-8 stainless steel were studied in simulated biofilm environment by various electrochemical methods ,including measurements of the corrosion potential, polarization curves,galvanic current and electrochemical impedance. The results show that such an approach is informative to reveal “how” and “to what extent” biofilm can influence the metal corrosion process.

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 …

Studies Of Electrochemical Characteristics Of Pasted Nickel Hydroxide Electrode With Surface Deposited Cobalt, Xian-You Wang, Yun-Shi Zhang, Jie Yan, Zheng Zhu, Hua-Tang Yuan, De-Ying Song

Journal of Electrochemistry

The surface of the spherical nickel hydroxide particles used as an active material in pasted nickel electrodes is surface-deposited with cobalt. This paper investigated the effects of the amount of cobalt deposit on the characteristics of nickel hydroxide electrode. The performances of the electrode, such as discharge capacity, utilization of active material and reversibility of Ni(OH)₂/NiOOH redox reaction, were studied by comparing the charging/discharging curves and cyclic voltammograms. The mechanism of action of cobalt deposits has been described in terms of the electrochemical impedance spectroscopy of nickel hydroxide electrode.

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 …

Electrodeposition Of Neodymium-Iron Group Alloy Films In (P-Ch3C6H4So3)3Nd System, Peng Liu, Ye-Xiang Tong, Qi-Qin Yang, Yan-Sheng Yang

Journal of Electrochemistry

Neodymium p-toluenesulfonate was prepared and applied to the electrodepositon of neodymium-iron group alloy films. This salt has high solubility in DMF and can be dehydrated easily. Cyclic voltammograms of Pt electrode in (p-CH₃C₆H₄SO₃) 3Nd + MCl₂(M=Fe,Co,Ni) + DMF indicated that the neodymiun-iron group alloys can be elcetrodeposited from this medium, the Nd-Fe, Nd-Co and Nd-Ni films were obtained by electrolysis at constant potential. The Nd-Fe, Nd-Co and Nd-Ni films are amorphous in which the rare earth contents are in the range of 15 at%～60 at% as analyzed by XRD and …

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 …

Effect Of Stress On Electrochemical Behaviour Of Various Thermal History Zones And Different Phase Structures On The Weldment For Low Alloy Steel, Yin-Shun Wu, De-Yu Liu, Bei Cao, Feng-Li Wang, Zhi Fang, Lin Zhang, Zheng-Rong Zhang, Hai Yang

Journal of Electrochemistry

The electrochemical behaviour of various thermal history zones on the weldment for steel 16Mn and also of the ferrite, pearlite in various zones was measured by use of a self-developed measuring technique for investigating the electrochemicl behaviour of single and mixed phase structures in metal materials. Especially the effect of stress on this electrochemical behaviour was investigated. The results showed that by comparison with non-stress condition, the free corrosion potential of the various thermal history zones and of the ferrite, pearlite under stress condition was shifted in negative direction, correspondingly their free corrosion current density was increased, the free corrosion …

Electrohydrodimerization Of Fumarodinitrile On Liquid Gallium Electrode, He Wei, Huang Ying, Sheng-Tao Zhang

Journal of Electrochemistry

Electrohydrodimerization (EHD) of fumarodinitrile on liquid gallium electrode can take place not only in hydrotropic solution of tetraethylammonium p-toluenesulphonate (TEA-PTS), but also in aqueous solution containing low concentration of strong surfactants, such as TritonX-100. In solution without organic surfactant, FDN yields a single two-electron reduction wave corresponding to the formation of a saturated monomer called as butanedinitrile. If some TEA-PTS or TritonX-100 is added into the solution, the original two-electron wave is splitted into two continuous single-electron reduction wave and corresponding EHD of fumarodinitrile is obtained.

Macrocyclic Antibiotics As Separation Agents, Daniel W. Amstrong

Chemistry Faculty Research & Creative Works

Macrocyclic antibiotics having ring structures with at least 10 members act as separation agents in crystallization, precipitation, filtration, electrophoresis and chromatography. The macrocyclic antibiotics include ansamacrolides, macrolides, marocyclic peptides, polyenes and derivatives thereof. The process has been found to be especially advantageous for separation of optical isomers by electrophoresis and chromatography.

Role Of Zeta Potential In Micro-Carrier Process, Pallavi Mehta

Theses

The micro-carrier process recently developed at NJIT is a new high rate settling technology for water and wastewater treatment. This process utilizes the micro-cater as a flocculating enhancement agent to achieve rapid removal of colloidal particles. This thesis consist of two parts, namely, 1) A review of the flocculation process utilized in water and wastewater treatment, and 2) An experimental program to evaluate the role of zeta potential in the flocculation process.

The results of this study indicated that the DLVO theory (Darjaguin, Landau, Overbeek, Verwey theory) is applicable to micro-cater process in the absence of polyelectrolytes. The best flocculation …

Classification Of Explosives Transformation Products In Plant Tissue, Steven L. Larson, Robert P. Jones, Lynn Escalon, Don Parker

United States Army Corps of Engineers, Omaha District

Explosives contamination in surface or groundwater used for the irrigation of food crops and phytoremediation of explosives-contaminated soil or water using plant-assisted biodegradation have brought about concerns as to the fate of explosives in plants. Liquid scintillation counting, high-performance liquid chromatography, and gel permeation chromatography were utilized to characterize explosives (hexahydro-1,3,5-trinitro-1,3,5-triazine and trinitrotoluene) and their metabolites in plant tissues obtained from three separate studies. Analyzing tissues of yellow nutsedge (Cyperus esculentus), corn (Zea mays), lettuce (Lacuta sativa), tomato (Lyopersicum esculentum), radish (Raphanus sativus), and parrot feather (Myriophyllum aquaticum) …

Classification Of Torbanite And Cannel Coal. Ii. Insights From Organic Geochemical And Multivariate Statistical Analysis, Zhiwen Han, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Petrographic and megascopic criteria have traditionally been used as the basis for the classification of torbanite and cannel coal. For this study, it was hypothesized that modern analytical organic geochemical and multivariate statistical techniques could provide an alternative approach. Towards this end, the demineralized residues of 14 torbanite (rich in Botryococcus-related alginite) and cannel (essentially, rich in organic groundmass and/or sporinite) coal samples were analyzed by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Cluster analysis performed on the Py-GC/MS data clearly distinguished the torbanite from the cannel coal, demonstrating a consistency between the chemical properties and the petrographic composition. All the torbanite …

Effects Of Ozonation On Cod Elimination Of Substituted Aromatic Compounds In Aqueus Solution, Şermi̇n Gül, Osman Seri̇ndağ, Hami̇t Boztepe

Turkish Journal of Chemistry

The chemical oxygen demand (COD) change of various substituted aromatic compounds, namely benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, sulfanilic acid, nitro benzene, resorcinol, p-cresol, o- cresol, o-toluidine, aniline and 8-hydroxyquinoline were investigated at ozone doses of 5, 10, 15 and 20 mg O_{3}\cdotmin^{-1}, respectively. Percent COD removal of initial compounds after ozonation was compared with reported biodegradation results. The pH change and percent removal of selected compounds were also evaluated in ozone does of 20 mg O_{3}\cdotmin^{-1} up to 80 min. ozonation. The results showed that high ozone doses are needed to obtain better elimination of initial compounds and also …

Determination Of Patent Blue V And Carmoisine In Gelatine Desserts By Derivative Spectrophotometry, Yüksel Özdemi̇r, Ayşe Arzu Akkan

Turkish Journal of Chemistry

A first-derivative spectrophotometric method was developed for quantitative determination of two synthetic organic dyes, Carmoisine and Patent Blue V, which are under governmental regulations all over the world because of their toxicity and carcinogenity. In this study, Carmoisine and Patent Blue V were simultaneously determined in their binary mixtures by first-derivative spectrophotometry. The method was applied to different gelatine desserts. The first-derivative derivative method did not eliminate turbid background in the samples. A simple background correction procedure involving a C_{18}-cartridge sample preparation step was developed for determination of dyes in gelatine dessert by first-derivative spectrophotometry. The C_{18}-cartridge sample preparation step …

Chlorination Of Two Turkish Lignites In Water And Water-Carbon Tetrachloride Media, Semra Karaca, Yücel Yaşar Kadioğlu, Sami̇h Bayrakçeken, M. Şahi̇n Gülaboğlu

Turkish Journal of Chemistry

The chlorine uptake of two Turkish lignites during chlorinolysis with chlorine gas in water and water-carbon tetrachloride media at ambient pressure (\cong 610 mmHg) was examined. The effects of speed of stirring (5-20s^{-1}), particle size (74-88, 150-180 and 250-425 \mu m), temperature (13-70°C) and chlorination time (0-18000 s) were studied. It is shown that the amount of chlorine uptake of both coals increased with decreasing particle size and increasing temperature.

Hydrogen Evolution At Platinum (Pt) And At Platinized Platinum (Ptz) Cathodes, Bi̇rgül Yazici

Turkish Journal of Chemistry

In this study, the cathodic behaviours of bright platinum (Pt) and at platinized platinum (Ptz) on the platinum anode were investigated in a 1M Na_2SO_4 electrolyte (pH, from 2 to 8) by means of electrolysis. The theoretical (\Delta Erev) and experimental (\Delta E_{exp}) discharge potentials and the cathodic overpotentials (\etac) of the systems were determined. The amounts of hydrogen gas produced at different times on the cathodes at a constant potential (5V) were measured and the hydrogen yield was calculated. The resulting scheme has been very helpful to obtain wodified electrocatalytic coating and electrode structures at Ptz cathode, able to …

Reaction Mechanism And Kinetics Of Aqueous Solutions Of Primary And Secondary Alkanolamines And Carbon Dioxide, Olgac Bavbek, Erdoğan Alper

Turkish Journal of Chemistry

The mechanism and kinetics of the reaction between aqueous solutions of CO_2 and the alkanolamines 1-amino-2-propanol, 3-amino-1-propanol,2-methyl aminoethanol and 2-ethyl aminoethanol were investigated using a stopped flow technique. It was found that the reaction orders according to power law kinetics were between 1.1 and 2.0, depending on the alkanolamine and the concentration ranges investigated. This fractional order was therefore considered to be further evidence that carbamate formation takes place according to a zwitterion mechanism rather than a one-step reaction. The kinetic rate parameters for these alkanolamines were evaluated from experimental data at 303 K according to this mechanism.

No(Y) Partitioning From Measurements Of Nitrogen And Hydrogen Radicals In The Upper Troposphere, E. R. Keim, S. A. Mckeen, R. S. Gao, Stephen G. Donnelly Ph.D., R. C. Wamsley, L. A. Del Negro, D. W. Fahey, T. F. Hanisco, E. J. Lanzendorf, M. H. Proffitt, J. J. Margitan, E. J. Hintsa, L. Jaeglé, C. R. Webster, R. D. May, D. C. Scott, R. J. Salawitch, J. C. Wilson, C. T. Mcelroy, E. L. Atlas, F. Flocke, T. P. Bui

Chemistry Faculty Publications

Recent studies using NO, NO(y), OH and HO2 (HO(X)) observations have postulated acetone and convection of peroxides as significant sources of HO(X) in the upper troposphere (UT). This work focuses on the effect these additional HO(X) sources have on the modeled NO(y) partitioning and comparisons of the modeled NO(x)/NO(y) ratio to observations. The measured NO(x)/NO(y) ratio is usually much higher than predicted regardless of the presence of acetone in the model. The exception occurs for air parcels having low NO(y) and O3 values. For these air parcels the measured NO(x)/NO(y) ratio is much lower than the calculated ratio unless acetone …

A Comparison Of Observations And Model Simulations Of NoX/NoY In The Lower Stratosphere, R. S. Gao, D. W. Fahey, L. A. Del Negro, Stephen G. Donnelly Ph.D., E. R. Keim, J. A. Neuman, E. Teverovskaia, P. O. Wennberg, T. F. Hanisco, E. J. Lanzendorf, M. H. Proffitt, J. J. Margitan, J. C. Wilson, J. W. Elkins, R. M. Stimpfle, R. C. Cohen, C. T. Mcelroy, T. P. Bui, R. J. Salawitch, S. S. Brown, A. R. Ravishankara, R. W. Portmann, M. K.W. Ko, D. K. Weisenstein, P. A. Newman

Chemistry Faculty Publications

Extensive airborne measurements of the reactive nitrogen reservoir (NOy) and its component nitric oxide (NO) have been made in the lower stratosphere. Box model simulations that are constrained by observations of radical and long-lived species and which include heterogeneous chemistry systematically underpredict the NOx (= NO + NO2) to NOy ratio. The model agreement is substantially improved if newly measured rate coefficients for the OH + NO2 and OH + HNO3 reactions are used. When included in 2-D models, the new rate coefficients significantly increase the calculated ozone loss due to NOx and modestly change the calculated ozone abundances in …

Thermal Characterization Of Pmma Thin Films On Silica Using Modulated Differential Scanning Calorimetry, Crystal E. Porter, Frank D. Blum

Chemistry Faculty Research & Creative Works

The number of studies of thin polymer films has increased over recent years as technological processes incorporate the use of nanomaterials. An enhanced understanding of these films would enable us to predict bound-polymer behavior and thus improve the efficiency of processes and the quality of products. This is especially true as the thickness of the films approach molecular dimensions. The glass transition temperature of a polymer is one of the most important properties for characterization because it indicates how the polymer might perform macroscopically. when a polymer is confined, such as one the surface of a substrate, its behavior is …

Dynamics Of Acrylic Coupling Agents At Interfaces Of Composites, Hyoryoon Jo, Frank D. Blum

Chemistry Faculty Research & Creative Works

Most applications of polymers involve composites, wherein a polymer is used in conjunction with another material, typically a solid fiber or filler. A coupling agent can enhance the adhesion between a polymer matrix and an inorganic filler. Organofunctional silanes, RSiX are often used as coupling agents. The methoxy or ethoxy group, X, can typically be hydrolyzed with water and an acid or a base catalyst in a protic solvent. The silanol groups of a hydrolyzed coupling agent can condense with other silanol groups from a glass surface, while the alkyl group, R, blends physically or bonds chemically to the polymer …

The Display Of Photographic-Quality Images On The Web: A Comparison Of Two Technologies, Chiang S. Jao, Daniel B. Hier, Steven U. Brint

Chemistry Faculty Research & Creative Works

Downloading Medical Images on the Web Creates Certain Compromises. the Tradeoff is between Higher Resolution and Faster Download Times. as Resolution Increases, Download Times Increase. High-resolution (Photographic Quality) Electronic Images Can Potentially Play a Key Role in Medical Education and Patient Care. on the Internet, Images Are Typically Formatted as Graphics Interchange Format (GIF) or the Joint Photographic Experts Group (JPEG) Flies. However, These Formats Are Associated with Considerable Data Loss in Both Color Depth and Image Resolution. Furthermore, These Images Are Available in a Single Resolution and Have No Capability of Allowing the User to Adjust Resolution as Needed. …

Synthesis Of Benzoxazoles Containing Allyl Crosslinking Sites Via Claisen Rearrangements, Leslie K. Hutson

Browse all Theses and Dissertations

The reaction of diethyl 2,5-dihydroxyterephthalate with allyl bromide/K2CO3 in DMF followed by hydrolysis provided 2,5-di(allyloxy)terephthalic acid. The conversion of 2,5-di (allyloxy)terephthalic acid to 1,4-di(2-benzoxazolyl)-2,5-di(allyloxy)benzene in PPSE was unsuccessful. However, the reaction of 1,4-di(2-benzoxazolyl)-2,5- dihydroxybenzene with allyl bromide/K2CO3 provided 1,4-di(2-benzoxazolyl)-2,5- di(allyloxy)benzene. DSC analysis indicated that 1,4-di(2-benzoxazolyl)-2,5- di(allyloxy)benzene undergoes a Claisen rearrangement to the corresponding diallyl product. The synthesis of 2-allyloxy-1,4-di(2-benzoxazolyl)benzene was carried out using 2-hydroxy-1,4-di(2-benzoxazolyl)benzene as starting material. DSC analysis was inconclusive with respect to a Claisen rearrangement. The reaction of 2-allyloxybenzoic acid with 2,2-bis(3-amino-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane in PPSE was unsuccessful but the reaction of 2,2-bis(2-(2-hydroxyphenyl)-5-benzoxazolyl)-1,1,1,3,3,3-hexafluoropropane with allyl bromide/K2CO3 in DMF provided 2,2-bis(2-(2- …