@article{zhu_kolar_shah_cheng_lim_2018, title={Simultaneous mitigation of p- cresol and ammonium using activated carbon from avocado seed}, volume={9}, ISSN={2352-1864}, url={http://dx.doi.org/10.1016/J.ETI.2017.10.006}, DOI={10.1016/J.ETI.2017.10.006}, abstractNote={Avocado seed was used as a precursor to prepare an activated carbon (AAC-MA) via physiochemical activation with methanesulfonic acid. The AAC-MA was systematically tested in batch systems for the removal of p-cresol (single-solute) and p-cresol and ammonium (binary solute). It was found that the kinetic data of p-cresol adsorption conformed to a pseudo-second-order model suggesting a predominantly chemisorption process. Additionally, the equilibrium data of p-cresol adsorption in a single solute system were found to follow Redlich–Peterson isotherm. Data analysis of the binary solute studies indicated that extended Langmuir isotherm was the most suitable to describe adsorption of p-cresol and ammonium on AAC-MA. It is also observed that the presence of ammonium did not affect adsorption of p-cresol. On the other hand, presence of p-cresol negatively influenced adsorption of ammonium. Our research suggests that AAC-MA can potentially serve as a waste management tool for mitigation of ammonium and p-cresol from aqueous systems.}, journal={Environmental Technology & Innovation}, publisher={Elsevier BV}, author={Zhu, Yiying and Kolar, Praveen and Shah, Sanjay B. and Cheng, Jay J. and Lim, P.K.}, year={2018}, month={Feb}, pages={63–73} }
 @article{zhu_kolar_shah_cheng_lim_2016, title={Avocado seed-derived activated carbon for mitigation of aqueous ammonium}, volume={92}, ISSN={0926-6690}, url={http://dx.doi.org/10.1016/J.INDCROP.2016.07.016}, DOI={10.1016/j.indcrop.2016.07.016}, abstractNote={There is a significant interest in value-addition of agricultural residues. In the present research, a novel avocado seed-activated carbon prepared from methanesulfonic acid (denoted as AAC-MA) was systematically tested as an adsorbent for removal of ammonium for the first time. SEM characterization technique was employed to identify the structural and morphological properties of the prepared carbon. The effects of pH, adsorbent dosage, initial NH4+ concentrations, and contact time on ammonium removal from aqueous solution were also investigated. Moreover, different kinetic and isotherm models were fit to the experimental data to gain a better understanding of the efficiency and applicability of the adsorption system. The pseudo-second order kinetic model was found to best describe the ammonium adsorption. The equilibrium data were found to conform best to Langmuir isotherm model with a theoretical maximum adsorption capacity of 5.4 mg g−1 at 25 °C. The results clearly suggested that the novel avocado-derived can potentially mitigate ammonium from aqueous systems.}, journal={Industrial Crops and Products}, publisher={Elsevier BV}, author={Zhu, Yiying and Kolar, Praveen and Shah, Sanjay B. and Cheng, Jay J. and Lim, P.K.}, year={2016}, month={Dec}, pages={34–41} }
 @article{min_choi_chung_ahn_ryoo_lim_2008, title={p-aminophenol synthesis in an organic/aqueous system using Pt supported on mesoporous carbons}, volume={337}, ISSN={["0926-860X"]}, DOI={10.1016/j.apcata.2007.12.004}, abstractNote={The biphasic conversion of nitrobenzene to p-aminophenol (PAP) via Pt/C-catalyzed hydrogenation of nitrobenzene and an acid-catalyzed rearrangement of the N-phenylhydroxylamine intermediate was studied. The effects of Pt/C catalyst loading, type of carbon support, reaction temperature, acid catalyst concentration, and additives on the reaction rate and PAP selectivity were investigated. At a given catalyst loading, nitrobenzene conversion and PAP selectivity were favored under a high reaction temperature and a high aqueous acid concentration. An increase in Pt/C catalyst loading leads to an increased hydrogenation rate but a lower PAP selectivity. Nitrobenzene conversion and PAP selectivity are both promoted by a small addition of N,N-dimethyl-n-dodecylamine, which may act as a phase transfer agent or emulsifier. Pt catalysts supported on novel mesoporous carbons – CMK-1 and CMK-3, which have uniform pore diameters of 3 and 4.5 nm – significantly outperform their counterpart supported on activated carbon with micropores. Two percent Pt/CMK-1 shows a catalytic activity equivalent to that of 5% Pt/C, but with significantly better PAP selectivity, i.e., 84% compared to 72%.}, number={1}, journal={APPLIED CATALYSIS A-GENERAL}, author={Min, Kyung-Il and Choi, Jung-Sik and Chung, Young-Min and Ahn, Wha-Seung and Ryoo, Ryong and Lim, P. K.}, year={2008}, month={Mar}, pages={97–104} }
 @article{lim_tam_yeung_lam_2007, title={Effect of hydrogen on dangling bond in a-Si thin film}, volume={61}, ISSN={["1742-6588"]}, DOI={10.1088/1742-6596/61/1/142}, abstractNote={Concentrations of the Si-H vibration bond and the dangling bond in amorphous silicon films were studied using FTIR and ESR techniques respectively as a function of annealing temperature in the range from 20°C to 950°C. It was found that the concentration of Si-H did not change much for temperatures up to 350°C and then dropped monotonically and became negligible at temperatures above 850°C, while the concentration of SiH2 increased with temperature and attained a maximum at 450°C and then decreased with temperature there after. The ESR signal dropped with temperature, up to 200°C, and fell below the detection limit of our spectrometer in the range 200°C-500°C. The ESR signal recovered when annealing temperature was higher than 550°C. The Si-H, SiH2, ESR and optical absorption signals were found to be highly correlated to each other and could be interpreted in a consistent manner.}, journal={PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON NANOSCIENCE AND TECHNOLOGY}, author={Lim, P. K. and Tam, W. K. and Yeung, L. F. and Lam, F. M.}, year={2007}, pages={708–712} }
 @article{deng_ding_wu_shan_lim_gu_2007, title={Study on thermal behaviors of Li/H atom in the bulk graphite by molecular dynamics method}, volume={42}, DOI={10.1007/s10853-006-1124-2}, number={18}, journal={Journal of Materials Science}, author={Deng, B. and Ding, K. and Wu, Z.-W. and Shan, L.-Y. and Lim, P. K. and Gu, C.-X.}, year={2007}, pages={7972–7976} }
 @article{lim_tam_2006, title={Local vibrational modes and the optical absorption tail of amorphous silicon}, volume={20}, DOI={10.1142/s0217979206041197}, abstractNote={ Local vibrational modes of Si - H is an important research area in recent years. Local vibrational modes of chemical bonds between Si atom and other impurity atoms such as H and O in amorphous silicon films produced by radio frequency sputtering were studied by means of Fourier transform infrared spectroscopy. The concentrations of Si - H , Si - O and Si - C in the sample were calculated. It was found that the concentration of Si - H bond varied significantly when the material was annealed at temperatures Ta >600 K and tended to zero for Ta >1000 K . The optical absorption edge was also found to depend strongly on the thermal history of the amorphous semiconductor. A strong correlation between the optical absorption coefficient and the concentration of Si - H was also observed. }, number={25, 26 & 27, Pt. 2}, journal={International Journal of Modern Physics B: Condensed Matter Physics, Statistical Physics, Applied Physics}, author={Lim, P. K. and Tam, W. K.}, year={2006}, pages={4261–4266} }
 @article{dong_wang_fan_lu_zhu_lim_tang_2005, title={Nd-doped GdVO4 films prepared by pulsed-laser deposition on SiO2/Si substance}, volume={86}, ISSN={["1077-3118"]}, DOI={10.1063/1.1898439}, abstractNote={Nd-doped GdVO4(Nd:GdVO4) films with a-axis preferred orientation were fabricated on SiO2∕Si substrate by pulsed-laser deposition. Fluorescences at around 1065.0 and 1342.5 nm, corresponding to F3∕24→I11∕24 and F3∕24→I13∕24 transitions, respectively, were excited simultaneously with an 808 nm diode laser. Waveguide behaviors in the film were investigated by using the prism coupling technique at the wavelength of 632.8 nm. Both TE and TM mode spectra revealed that favorable light confinements were achieved within the Nd:GdVO4 waveguide layer. Additionally, the optically anisotropic properties of the film were studied in detail.}, number={15}, journal={APPLIED PHYSICS LETTERS}, author={Dong, ZG and Wang, FY and Fan, YX and Lu, P and Zhu, SN and Lim, PK and Tang, TB}, year={2005}, month={Apr} }
 @article{chung_ahn_lim_2000, title={Organic/aqueous interfacial synthesis of poly(2,6-dimethyl-1,4-phenylene oxide) using surface-active copper complex catalysts}, volume={192}, ISSN={["0926-860X"]}, DOI={10.1016/S0926-860X(99)00401-9}, abstractNote={The coupling polymerization of 2,6-dimethylphenol to poly(2,6-dimethyl-1,4-phenylene oxide) was carried out in an aqueous–chloroform biphasic mixture using copper complexes of substituted ethylenediamines as surface-active catalysts. Copper-N,N-dibutylethylenediamine complex gave the highest reaction rate and produced a polymer with an average molecular weight of 48 000 in a 95% yield. The optimum ligand to catalyst ratio and organic to aqueous volume ratio were found to be 3 : 1 and 1 : 1, respectively. The reaction rate also depended strongly on the aqueous ammonia concentration, stirring speed and the emulsifier concentration. The reaction orders with respect to the substrate, catalyst complex and oxygen are 1.0, 1.7 and 0.1, respectively, and the activation energy was approximately 11.7 kcal/mol. A reaction mechanism is proposed which yields a model rate expression in good agreement with the experimental findings.}, number={2}, journal={APPLIED CATALYSIS A-GENERAL}, author={Chung, YM and Ahn, WS and Lim, PK}, year={2000}, month={Feb}, pages={165–174} }
 @article{chung_ahn_lim_1999, title={Biphasic coupling polymerization of 2,6-dimethylphenol using surface-active copper complex catalysts}, volume={148}, ISSN={["1381-1169"]}, DOI={10.1016/S1381-1169(99)00161-2}, abstractNote={Coupling polymerization of 2,6-dimethylphenol to poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) was carried out in an 1:1 aqueous–chloroform biphasic mixture using Cu–surface active ligand complex catalysts. Bidentate ligands were superior to monodentate ligands in promoting the oxidative coupling possibly due to their higher surface-activity and ability to form a binuclear complex with two metal ions. In particular, N,N-dibutylethylenediamine complex of copper gave the highest reaction rates and produced a polymer with an average molecular weight of 48,000 in a 95% yield. Spontaneous phase separation induced by the surface-active ligand made it possible to recover the catalyst complex segregated at the middle emulsion layer in a compact form. Biphasic reaction with a suitable surface-active ligand was found to be more effective than homogeneous counterpart to promote the oxidative coupling reaction and was more favorable for forming higher molecular weight polymer products.}, number={1-2}, journal={JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL}, author={Chung, YM and Ahn, WS and Lim, PK}, year={1999}, month={Dec}, pages={117–126} }
 @article{leung_man_lim_chan_gaspari_zukotynski_1999, title={Determination of the sp(3)/sp(2) ratio of a-C : H by XPS and XAES}, volume={254}, ISSN={["0022-3093"]}, DOI={10.1016/s0022-3093(99)00388-9}, abstractNote={X-ray photoelectron spectroscopy and X-ray excited Auger electron spectroscopy were used to determine some of the properties of diamond like amorphous carbon films deposited using saddle field glow discharge of methane. By applying the chemical shift technique and curve fitting technique to the C1s peak in the X-ray photoelectron spectrum of the film, we were able to determine the sp3/sp2 bonding ratio of the films. The ratio from this method was in agreement (±1%) with that calculated from the X-ray excited Auger electron spectrum of the same film. The method was also applied to a-C:H films doped with different impurities (boron and phosphorus) in amounts varying from 1% to 20%. We found that the sp3/sp2 ratio of the film was dependent on the deposition parameters and on types of impurities and their concentrations.}, journal={JOURNAL OF NON-CRYSTALLINE SOLIDS}, author={Leung, TY and Man, WF and Lim, PK and Chan, WC and Gaspari, F and Zukotynski, S}, year={1999}, month={Sep}, pages={156–160} }
 @article{chung_kang_ahn_lim_1999, title={Homogeneous and biphasic autoxidation of tetralin catalyzed by transition metal salts and complexes}, volume={137}, ISSN={["1381-1169"]}, DOI={10.1016/S1381-1169(98)00080-6}, abstractNote={The biphasic autoxidation of tetralin was carried out using various Co, Ni and Mn complexes as catalysts. Cobalt–N,N′-dimethylethylenediamine complex, which is amphiphilic and surface-active, was found to be most effective; it could be easily recovered in a compact emulsion layer after the reaction and could be reused with no apparent loss of activity. The biphasic reaction differs from the homogeneous counterpart in that (1) little hydroperoxide product is formed, (2) there is lesser sensitivity to product inhibition and a greater degree of conversion and (3) there is an easier catalyst recovery and substrate recycle.}, number={1-3}, journal={JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL}, author={Chung, YM and Kang, KK and Ahn, WS and Lim, PK}, year={1999}, month={Jan}, pages={23–29} }
 @article{leung_man_so_lim_chan_gaspari_zukotynski_1999, title={Photothermal deflection spectroscopy and transmission measurements of a-C : H films}, volume={254}, ISSN={["0022-3093"]}, DOI={10.1016/s0022-3093(99)00441-x}, abstractNote={Absorption coefficient of a-C:H film prepared by saddle-field glow-discharge chemical vapor deposition was measured by means of photothermal deflection spectroscopy and transmission measurements. The absorption spectra of these films are divided into a larger absorption region and a smaller absorption region. The larger absorption region can be interpreted in terms of the Tauc model and an optical gap is obtained for the a-C:H film. The smaller absorption region can be analyzed in terms of the Urbach tail and yields information about the band tails of the a-C:H film. The effect of doping on the absorption tails and the optical gap is also reported. We found that both the optical gap and the breadth of the band tail decreased with the concentration of the impurities, phosphorous or hydrogen. Also there is a correlation between the band tail spread and the optical gap. The breadth of the band tail increases with the optical gap.}, journal={JOURNAL OF NON-CRYSTALLINE SOLIDS}, author={Leung, TY and Man, WF and So, SK and Lim, PK and Chan, WC and Gaspari, F and Zukotynski, S}, year={1999}, month={Sep}, pages={151–155} }
 @article{norman_wilhite_pham_lim_brown_1998, title={Biphasic synthesis of 2-phenylpropionic acid and ester by interfacial carbonylation of alpha-methylbenzyl bromide}, volume={2}, ISSN={["1083-6160"]}, DOI={10.1021/op9701292}, abstractNote={An interfacial synthesis technique has been successfully extended to the carbonylation of α-methylbenzyl bromide in an organic−aqueous sodium hydroxide mixture at 35−60 °C and 1 atm using surface-active palladium−(4-dimethylaminophenyl)diphenylphosphine complex as the catalyst and dodecyl sodium sulfate as the emulsifier. Depending on the reaction conditions, 2-phenylpropionate in the form of sodium salt and an ester was obtained in 0−83% yield, along with varying amounts of side products that included α-methylbenzyl alcohol, 2,3-diphenylbutane, di(α-methylbenzyl)ether, and an asymmetric ether derived from the substrate and an alcoholic medium. When 2-methyl-1-butanol or 2-ethyl-1-hexanol was used as the organic phase, 2-phenylpropionate ester and sodium salt were obtained in 40−83% yield, with a maximum yield obtained at an optimal aqueous base concentration of about 5 M. At a lower aqueous base concentration, more of α-methylbenzyl alcohol was formed, whereas at a higher aqueous base concentration, more...}, number={6}, journal={ORGANIC PROCESS RESEARCH & DEVELOPMENT}, author={Norman, C and Wilhite, BA and Pham, D and Lim, PK and Brown, PA}, year={1998}, pages={366–378} }
 @article{chung_ahn_lim_1998, title={Biphasic synthesis of alpha-tetralone using nickel complex catalysts}, volume={15}, ISSN={["0256-1115"]}, DOI={10.1007/bf02707104}, number={5}, journal={KOREAN JOURNAL OF CHEMICAL ENGINEERING}, author={Chung, YM and Ahn, WS and Lim, PK}, year={1998}, month={Sep}, pages={527–532} }
 @article{fields_lim_roberts_1998, title={Catalytic destruction of methyl tertiary butyl ether (MTBE) with a Pt/Rh monolithic automotive exhaust catalyst}, volume={15}, ISSN={["1873-3883"]}, DOI={10.1016/s0926-3373(97)00039-8}, abstractNote={Abstract The destruction of methyl tertiary butyl ether (MTBE) was studied using a Pt/Rh monolithic automotive catalyst. Inlet temperatures to the catalyst ranged from about 450 to about 775 K, and the amount of oxygen in the feed ranged from 0 to about 120% of stoichiometric. The presence of carbon dioxide, water and i -octane (2,2,4-trimethyl pentane) in the feed was also investigated. The decomposition of MTBE into methanol and i -butene (2-methyl-1-propene) was kinetically significant at these conditions. Both methanol and i -butene were present in the effluent from the catalyst at all operating conditions. Carbon dioxide and water had no significant effect on the kinetics of MTBE disappearance. The rate of MTBE destruction was faster than the oxidation of i -octane.}, number={1-2}, journal={APPLIED CATALYSIS B-ENVIRONMENTAL}, author={Fields, DL and Lim, PK and Roberts, GW}, year={1998}, month={Jan}, pages={93–105} }
 @article{sk o'leary_lim_1998, title={Influence of the kinetic energy of localization on the distribution of electronic states in amorphous semiconductors}, volume={66}, ISSN={["1432-0630"]}, DOI={10.1007/s003390050637}, number={1}, journal={APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING}, author={SK O'Leary and Lim, PK}, year={1998}, month={Jan}, pages={53–58} }
 @article{chung_ahn_lim_1998, title={Organic-water interfacial synthesis of alpha-tetralone using nickel-tetraethylenepentamine complex catalysts}, volume={173}, ISSN={["0021-9517"]}, DOI={10.1006/jcat.1997.1908}, abstractNote={Abstract Biphasic autoxidation of tetralin to α-tetralone has been carried out using surface-active ligand complexes of nickel as catalysts, tetralin as the substrate and organic phase, and dodecyl sodium sulfate as an emulsifier. The major products formed under the mild reaction conditions of 60°C and 1 atm were α-tetralone and α-tetralol, and the highest selectivity of 71% to the preferred product α-tetralone was obtained with nickel-tetraethylenepentamine complex. Depending on the ligand used, ligand to catalyst ratio of 2:1 or 1:1 was optimum accelerating the reaction rate and phase separation. The organic-water phase volume ratio around which the maximum reaction rate was obtained varied somewhat with the ligand used in the reaction, but generally 1:1 or 2:1 was adequate. The reaction order with respect to oxygen shifted from first to zero as its partial pressure increased and the reaction order with respect to nickel catalyst concentration varied from 1.7 to 1, and subsequently to 0 with further increases in the metal concentration. A kinetic model based on a free radical mechanism is proposed which yields a rate law in accord with the experimental findings.}, number={1}, journal={JOURNAL OF CATALYSIS}, author={Chung, YM and Ahn, WS and Lim, PK}, year={1998}, month={Jan}, pages={210–218} }
 @article{chan_gaspari_allen_lim_moreno_sagnes_manage_szurmak_zukotynski_1998, title={Structural, optical, and electrical properties of doped hydrogenated diamond-like amorphous carbon films deposited using the dc saddle-field grow-discharge technique}, volume={16}, ISSN={["0734-2101"]}, DOI={10.1116/1.581030}, abstractNote={The dc saddle-field glow-discharge technique was employed to deposit undoped, phosphorus-doped and boron-doped hydrogenated diamond-like amorphous carbon films. The undoped films were grown using pure methane, while the doped films were grown using methane diluted with dopant gases (phosphine and diborane) in mole fraction ranging from 0.05 to 1×10−5. Secondary ion mass spectroscopy was used to determine the composition of these films. The results showed that various levels of doping in amorphous carbon films can be achieved predictably by using the appropriate mole fraction of dopant gases. The fractions of tetrahedral and trigonal bonds in the films were obtained using x-ray Auger electron spectroscopy. The optical energy gaps of the films were determined from optical absorption measurements. These data were correlated with the doping levels of the films. The electrical conductivities of the undoped and doped samples were determined at temperatures in the range from 225 to 380 °C. The activation energies were determined, and the corresponding conduction mechanisms were examined.}, number={2}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS}, author={Chan, WCW and Gaspari, F and Allen, T and Lim, PK and Moreno, E and Sagnes, E and Manage, D and Szurmak, J and Zukotynski, S}, year={1998}, pages={889–892} }
 @article{ahn_zhong_abrams_lim_brown_1997, title={Biphasic autoxidation of tetralin catalyzed by surface-active transition metal complexes}, volume={101}, ISSN={["1089-5647"]}, DOI={10.1021/jp9627234}, abstractNote={Biphasic autoxidation of tetralin has been carried out using surface-active tetramethylethylenediamine complexes of manganese, chromium, and nickel as catalysts, tetralin as the substrate and organic phase, and dodecyl sodium sulfate as emulsifier. Advantages of the biphasic reaction over the homogeneous and heterogeneous counterparts include avoidance of the use of a troublesome solvent, ease of catalyst recovery and substrate recycle, and attainment of high reactivity, selectivity, and reproducibility under mild reaction conditions (T ∼ 60 °C, P ∼ 1 atm). The main reaction products are α-tetralone and α-tetralol. The selectivity for the former decreases from 95% with the chromium complex to 90% with the nickel complex and 60% with the manganese complex, and the activity varies in a reverse order. The biphasic reaction stops at a bulk tetralin conversion of 35% due to the buildup of inhibitive, higher oxidation products. Similar product inhibition has been reported in one-liquid-phase systems. The biphas...}, number={4}, journal={JOURNAL OF PHYSICAL CHEMISTRY B}, author={Ahn, WS and Zhong, YP and Abrams, CF and Lim, PK and Brown, PA}, year={1997}, month={Jan}, pages={596–602} }
 @article{zhong_godfrey_lim_brown_1996, title={Biphasic synthesis of phenylacetic and phenylenediacetic acids by interfacial carbonylation of benzyl chloride and dichloro-p-xylene}, volume={51}, ISSN={["0009-2509"]}, DOI={10.1016/0009-2509(95)00300-2}, abstractNote={Abstract An organic-water interfacial technique has been successfully extended to the synthesis of phenylacetic and phenylenediacetic acids based on the use of surface-active palladium-(4-dimethylaminophenyl)diphenylphosphine complex in conjunction with dodecyl sodium sulfate to effect the carbonylation of benzyl chloride and dichloro- p -xylene in a toluene-aqueous sodium hydroxide mixture. The product yields at 60°C and 1 atm are essentially quantitative based on the substrate conversions, although carbon monoxide also undergoes a slow hydrolysis reaction along with the carbonylation reactions. The side reaction produces formic acid and is catalyzed by aqueous base but not by palladium. The phosphine ligand is stable to the carbonylation reactions and the palladium can be recovered quantitatively as a compact emulsion between the organic and aqueous phases after the reaction, but the catalytic activity of the recovered palladium is about a third of its initial activity due to product inhibition. The carbonylation of benzyl chloride has an activation energy of 100 kJ/mol, a first-order dependence on the catalyst and substrate concentrations, a zero-order dependence on the carbon monoxide partial pressure, and a variable-order dependence on the aqueous base concentration. A kinetic model is proposed which yields a rate law in accord with the experimental findings.}, number={5}, journal={CHEMICAL ENGINEERING SCIENCE}, author={Zhong, YP and Godfrey, VM and Lim, PK and Brown, PA}, year={1996}, month={Mar}, pages={757–767} }
 @article{frankel_mew_lim_roberts_1996, title={Oxidation of methanol over a palladium monolithic automotive catalyst}, volume={30}, ISSN={["0013-936X"]}, DOI={10.1021/es950760n}, abstractNote={The oxidation of methanol and its partial oxidation products, carbon monoxide and formaldehyde, were studied using a monolithic catalyst containing palladium. Experimental conditions simulated those in the catalytic converter of a methanol-fueled automobile. With a properly activated catalyst and a fuel-lean feed, carbon dioxide was the only carbon-containing product, and the methanol conversion above the light-off temperature of the catalyst appeared to be controlled by mass transfer from the bulk gas stream to the surface of the monolith. Under fuel-rich conditions, carbon monoxide and formaldehyde were formed along with carbon dioxide. The highest formaldehyde yield, about 4% of the methanol reacted, occurred at a relatively low feed temperature, about 350 K, essentially the light-off temperature of the catalyst. The formaldehyde yield decreased as the feed temperature increased and was essentially zero above about 600 K. When a thermally-deactivated catalyst was used, the formaldehyde yield increased significantly and formaldehyde was observed over a wider range of feed temperatures and under fuel-lean conditions. With the properly activated catalyst multiple steady states were observed in the form of a reaction hysteresis with respect to feed temperature. 23 refs., 10 figs., 1 tab.}, number={6}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={Frankel, KA and Mew, TM and Lim, PK and Roberts, GW}, year={1996}, month={Jun}, pages={1997–2003} }
 @article{zhong_abrams_lim_1995, title={BIPHASIC SYNTHESIS OF POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE) USING A SURFACE-ACTIVE COUPLING CATALYST .2. PROCESS IMPROVEMENTS, ADDITIONAL KINETIC RESULTS, AND PROPOSED REACTION-MECHANISM}, volume={34}, ISSN={["0888-5885"]}, DOI={10.1021/ie00044a003}, abstractNote={Significant process improvements, additional kinetic findings, and a proposed mechanism are presented for a previously reported biphasic synthesis of poly(2,6-dimethyl-1,4-phenylene oxide) that avoids the need for a toxic organic solvent. A switch from magnetic stirring to the more vigorous mechanical stirring coupled with the use of an emulsifier increases the rate of formation and molecular weight of the polymer product each by more than 500%. New data indicate that the reaction has an activation energy of 14.7 kcal/mol and a first-, second-, and 0.15-order dependence on the monomer, catalyst, and oxygen concentrations, respectively. The optimal phase ratio for a fast reaction is around 1:1, and the optimal aqueous ammonia concentration is around 0.26 M. The reaction profile shows an unusual accelerating-rate feature that suggests a shifting balance between chain-growth and emulsion stabilization effects on one hand and a site competition effect at the catalyst on the other hand. A mechanism is proposed which gives a rate law in good agreement with the experimental rate law. A successful extension of the biphasic technique to several carbonylation and autoxidation reactions suggests a general utility of the technique for chemical synthesis}, number={5}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={ZHONG, YP and ABRAMS, CF and LIM, PK}, year={1995}, month={May}, pages={1529–1535} }
 @article{wang_ng_lim_leung_wu_chen_1994, title={THE TORSION ROTATIONAL SPECTRAL STRUCTURE OF ETHANOL MOLECULES ADSORBED ON POLYCRYSTALLINE SILVER SUBSTRATE}, volume={6}, ISSN={["0953-8984"]}, DOI={10.1088/0953-8984/6/36/005}, abstractNote={A laser photoacoustic spectrometer (LPAS) using a branch-tunable carbon dioxide laser source and a piezoelectric transducer as a detector was employed to study the adsorption of ethanol on a polycrystalline silver surface at 108 K. The strength of bonding between adsorbate and substrate was found to lie between physisorption and chemisorption according to the values of heat of adsorption (33.2 kJ mol-1, 38.8 kJ mol-1, 39.5 W mol-1 and 44.2 kJ mol-1 obtained by thermal-desorption spectroscopy). A fine spectral structure of seven peaks was obtained in the region of 1045-1054 cm-1, which bears striking resemblance to that obtained by Fourier-transform infrared spectroscopy for gaseous ethanol. Taking into consideration the results of the thermal-desorption study, which suggests weak bonding between ethanol and the silver surface, this fine spectral structure was attributed to the internal torsional rotation of the ethanol adsorbates. To our knowledge, this work is the first report on a torsional-rotational fine spectral structure of ethanol adsorbate on a silver surface. Thus our findings show that torsional-rotational structure exists not only in free molecules as in the gas phase, but also in the adsorbate phase. The set-up used in this experiment was capable of providing 1 cm-1 fine spectral resolution at 1 L exposure sensitivity. The LPAS technique developed here has potential for studying other systems as well.}, number={36}, journal={JOURNAL OF PHYSICS-CONDENSED MATTER}, author={WANG, ZY and NG, CF and LIM, PK and LEUNG, HW and WU, JG and CHEN, HF}, year={1994}, month={Sep}, pages={7207–7215} }
 @article{mawson_mccutchen_lim_roberts_1993, title={THERMODYNAMICS OF HIGHER ALCOHOL SYNTHESIS}, volume={7}, ISSN={["0887-0624"]}, DOI={10.1021/ef00038a016}, abstractNote={The paper presents the results obtained with the ASPEN PLUS process simulation package for definition of the thermodynamic behaviour of the reactions by which higher alcohols are synthesized from CO/H 2 mixtures}, number={2}, journal={ENERGY & FUELS}, author={MAWSON, S and MCCUTCHEN, MS and LIM, PK and ROBERTS, GW}, year={1993}, pages={257–267} }
 @article{dautenhahn_lim_1992, title={BIPHASIC SYNTHESIS OF POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE) USING A SURFACE-ACTIVE COUPLING CATALYST}, volume={31}, ISSN={["0888-5885"]}, DOI={10.1021/ie00002a002}, abstractNote={We demonstrate the faisability and some of the potential advantages of interfacial synthesis on the coupling polymerisation of 2,6-dimethylphenol. The commercial production of poly(2,6-dimethyl-1,4-phenylene oxyde) (PPO) is based on the oxidative coupling of 2,6-dimethylphenol in pyridine or a mixture of pyridine and nitrobenzene. PPO is an important thermoplastic resin used in the manufacture of filter devices, valves seats, tuner strips, food trays, and surgical instruments}, number={2}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={DAUTENHAHN, PC and LIM, PK}, year={1992}, month={Feb}, pages={463–469} }
 @article{choi_all_overcash_lim_1992, title={CAPILLARY-FLOW MECHANISM FOR FUGITIVE EMISSIONS OF VOLATILE ORGANICS FROM VALVES AND FLANGES - MODEL DEVELOPMENT, EXPERIMENTAL-EVIDENCE, AND IMPLICATIONS}, volume={26}, ISSN={["0013-936X"]}, DOI={10.1021/es00027a004}, abstractNote={Experimental and model results are presented to show that the so-called «nonleaker» emissions of volatile organics from valves and flanges probably proceed by a capillary mechanism. A capillary-flow model is formulated based on theoretical consideration and field data, and equations are derived which permit a test of the model under laboratory conditions. Model predictions are shown to be confirmed by an experimental study of emission from a valve}, number={3}, journal={ENVIRONMENTAL SCIENCE & TECHNOLOGY}, author={CHOI, SJ and ALL, RD and OVERCASH, MR and LIM, PK}, year={1992}, month={Mar}, pages={478–484} }
 @article{ganesan_lloyd_gilleskie_lim_1989, title={SEGREGATION AND CHEMICAL CONVERSION AT OIL-WATER INTERFACE}, volume={44}, ISSN={["0009-2509"]}, url={http://dx.doi.org/10.1016/0009-2509(89)85242-x}, DOI={10.1016/0009-2509(89)85242-x}, abstractNote={Abstract Experimental evidence and theoretical consideration are presented to draw attention to the adsorptive power of the oil-water interface and the promising potential it provides for the development of an interfacial emulsion technique that can be useful for separation and materials conversion. It is shown that dissolved and suspended materials can be segregated into a compact emulsion in between water and an immiscible oil phase, and that such segragation facilitates the separation or conversion of the materials. On account of its property range being wider than that of solid-water and gas-water interfaces, the oil-water interface could provide a flexibility and versatility that would make the envisioned emulsion technique more useful than packed-bed and foam techniques. Other possible advantages may include a high capacity and high enrichment, and the availability of surface variation as a convenient process parameter.}, number={1}, journal={CHEMICAL ENGINEERING SCIENCE}, publisher={Elsevier BV}, author={GANESAN, S and LLOYD, PB and GILLESKIE, GL and LIM, PK}, year={1989}, pages={171–177} }
 @article{lloyd_ganesan_lim_1989, title={SEGREGATION OF METALS AT THE OIL-WATER INTERFACE - RESULTS AND IMPLICATIONS}, volume={28}, ISSN={["0888-5885"]}, DOI={10.1021/ie00089a013}, abstractNote={Experimental evidence and theoretical consideration are presented to draw attention to the adsorptive power of the oil-water interface and the promising potential it provides for the development of an interfacial emulsion technique that can be useful to metal recovery and materials conversion. It is shown that dissolved and suspended metals can be segregated into a compact emulsion in between water and an immiscible oil phase and that such segregation facilitates metal recovery and interfacial catalytic reactions. On account of its property range being wider than that of solid-water and gas-water interfaces, the oil-water interface could provide a flexibility and versatility that would make the envisioned interfacial technique more useful than packed-bed and foam techniques. Other possible advantages include high capacity and high enrichment and the availability of surface variation as a convenient process parameter. Specific applications of the proposed interfacial technique are considered with reference to metal recovery and photocatalytic waste treatment.}, number={5}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH}, author={LLOYD, PB and GANESAN, S and LIM, PK}, year={1989}, month={May}, pages={577–584} }
 @article{zhong_lim_1989, title={THE COPPER-CATALYZED REDOX REACTION BETWEEN AQUEOUS HYDROGEN-PEROXIDE AND HYDRAZINE .1. NEW EXPERIMENTAL RESULTS AND OBSERVATIONS}, volume={111}, ISSN={["0002-7863"]}, DOI={10.1021/ja00204a011}, abstractNote={Important new data are reported which make it possible to deduce the most probable mechanism of the copper-catalyzed redox reaction between aqueous hydrogen peroxide and hydrazine: 2H{sub 2}O{sub 2} + N{sub 2}H{sub 4} {yields} 4H{sub 2}O + N{sub 2}. The reaction is marked by an induction period {tau}{sub e} which varies inversely with the catalyst concentration but essentially independently with the peroxide and hydrazine concentrations. Trace amounts of cerium ion, hydroquinone, quinone, and o-phenylenediamine promote the reaction markedly. Ultrasonication accelerates the reaction, whereas a viscosity increase in the reaction solution has the opposite effect. Maleate ion produces a quantitative increase in nitrogen output above the stoichiometric equivalent of peroxide. The reaction shows no wall effect. The nitrogen and peroxide profiles and the rate are described.}, number={22}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={ZHONG, YP and LIM, PK}, year={1989}, month={Oct}, pages={8398–8404} }
 @article{lim_zhong_1989, title={THE COPPER-CATALYZED REDOX REACTION BETWEEN AQUEOUS HYDROGEN-PEROXIDE AND HYDRAZINE .2. REACTION-MECHANISM, MODEL ANALYSIS, AND A COMPARISON OF MODEL AND EXPERIMENTAL RESULTS}, volume={111}, ISSN={["0002-7863"]}, DOI={10.1021/ja00204a012}, abstractNote={In this paper we show that the kinetic findings lead logically to the most probable mechanism of the reaction. We use the experimental data to evaluate the kinetic parameters in the proposed mechanism and show that the resulting rate and integral expressions produce model results in close agreement with the experimental results}, number={22}, journal={JOURNAL OF THE AMERICAN CHEMICAL SOCIETY}, author={LIM, PK and ZHONG, YP}, year={1989}, month={Oct}, pages={8404–8410} }
 @article{chin_lim_1989, title={THE PEROXIDE-COUPLING KINETICS AND DISSOCIATION-CONSTANTS OF AQUEOUS CYSTEINE AND GLUTATHIONE - EXPERIMENTAL AND MODEL RESULTS, AND IMPLICATIONS}, volume={44}, ISSN={["0009-2509"]}, DOI={10.1016/0009-2509(89)85261-3}, abstractNote={The peroxide-coupling kinetics and various pKa values of cysteine and glutathione have been determined over a range of conditions. In the pH range 6–12 and the temperature range 0–35°C, both sulfhydryl compounds react with hydrogen peroxide (in the neutral, undissociated form) according to the same SN2 mechanism that applies to thiol compounds, i.e. The reaction involves neither a metal catalyst nor free-radical intermediates; it yields disulfide product essentially quantitatively. The rate law is given by where ko are 1.77 × 1010 (Ms)−1 and 51.0 kJ/mol, respectively, for cysteine, and 2.10 × 109 (Ms)−1 and 46.9 kJ/mol, respectively, for glutathione. The pKa values of the sulfhydryl compounds vary with temperature according to Parameter values of ΔH and ΔS are reported for the various proton groups. The nonradical nature of the peroxide-coupling reactions suggests that, in biological systems, the immunological function of sulfhydryl compounds against radical toxicity may derive less from a direct scavenging of radicals than from the removal of hydrogen peroxide as a source of their formation. Moreover, the rapidity and spontaneity of the SN2 reactions suggests that the function of sulfhydryl peroxidase may be less rate enhancement than the control of the reactive and otherwise harmful sulfenic acid intermediates.}, number={4}, journal={CHEMICAL ENGINEERING SCIENCE}, author={CHIN, FYC and LIM, PK}, year={1989}, pages={883–893} }
 @article{cha_berry_lim_1986, title={AEROBIC COUPLING OF AQUEOUS PHENOLS CATALYZED BY BINUCLEAR COPPER - RING SUBSTITUENT EFFECT AND THE KINETICS OF THE COUPLING OF O-METHYLPHENOL}, volume={32}, ISSN={["0001-1541"]}, DOI={10.1002/aic.690320314}, abstractNote={Abstract}, number={3}, journal={AICHE JOURNAL}, author={CHA, JA and BERRY, KB and LIM, PK}, year={1986}, month={Mar}, pages={477–485} }
 @article{giles_cha_lim_1986, title={THE AEROBIC AND PEROXIDE-INDUCED COUPLING OF AQUEOUS THIOLS .1. KINETIC RESULTS AND ENGINEERING SIGNIFICANCE}, volume={41}, ISSN={["0009-2509"]}, DOI={10.1016/0009-2509(86)85050-3}, abstractNote={Alkaline thiols undergo a rapid oxidative coupling reaction in the presence of oxygen or hydrogen peroxide; the oxygen reaction is catalyzed by trace copper whereas the peroxide reaction occurs spontaneously without the necessity of metal catalysis. Depending on the nature of the substrate—its molecular size and whether it contains any polar group—the disulfide, which is the coupling product, may be soluble or sparingly soluble in water. Water-soluble disulfides undergo further, although much slower, oxidation reactions to form higher oxidation products. In the oxygen reaction molecular oxygen is reduced sequentially to peroxide and then water. For n-propylthiol, the oxygen reaction has a first-order dependence on oxygen pressure and copper concentration; the reaction order with respect to thiolate changes from pseudo zeroth order to first and, then, second order as the reaction approaches completion. The peroxide reaction, on the other hand, has a strictly first-order dependence on the concentrations of thiolate and the non-dissociated hydrogen peroxide. The activation energies of the oxygen and peroxide reactions are, respectively, 9.5 ± 1.2 and 12.3 kcal/mol. A similar dependency on the kinetic parameters appears to hold for other thiols, although some variations are observed which arise from special features of individual systems. For aminothiols, the dependence on copper switches to second order below a certain catalyst concentration; for alkylthiols which form insoluble liquid disulfides, the oxygen reaction shows a pronounced sensitivity to stirring that arises from the tendency of the copper-thiolate and disulfide complexes to cluster and segregate at the water-disulfide interface. When coupled to the fact that many mercapto and sulfhydryl compounds of interest form disulfides which have low aqueous solubilities, the ease of the aerobic coupling reaction suggests that it may be used to separate soluble mercapto and sulfhydryl substances from aqueous media.}, number={12}, journal={CHEMICAL ENGINEERING SCIENCE}, author={GILES, DW and CHA, JA and LIM, PK}, year={1986}, pages={3129–3140} }
 @article{lim_giles_cha_1986, title={THE AEROBIC AND PEROXIDE-INDUCED COUPLING OF AQUEOUS THIOLS .2. REACTION-MECHANISMS, MODEL ANALYSIS, AND A COMPARISON OF THE MODEL AND EXPERIMENTAL RESULTS}, volume={41}, ISSN={["0009-2509"]}, DOI={10.1016/0009-2509(86)85051-5}, abstractNote={Kinetic results of the preceeding paper are used to formulate the most probable reaction mechanisms for the peroxide-induced and aerobic coupling of aqueous thiols. Parameters in the proposed mechanisms are evaluated for n-propylthiol using the results of independent measurements. A remarkably good agreement is achieved between the model and experimental results. The peroxide reaction, which is not affected by either copper ion or radical scavengers, is shown to be a nucleophilic substitution (SN 2) reaction which proceeds by a two-step mechanism as follows: RS− + H2O2 RSOH + OH− rate-determining RS− + RSOH → RSSR + OH− In the reaction the thiolate anion acts as the nucleophile while hydrogen peroxide and the transient sulfenic acid, RSOH, function as electrophiles. The most plausible mechanism for the copper-catalyzed, aerobic coupling reaction is as follows: Cu+ (RSSR)2+ + RS− (RSSR)Cu+ (RS−) + RSSR (RSSR)Cu+ (RS−) + RS− (RSSR)Cu+ (RS−)2− (RSSR)Cu+ (RS−)2− + O2 Cu+(RSSR)2+ + HO2− rate-determining RS− + H2O2 RSOH + OH− rate-determining RS− + RSOH → RSSR + OH− For the n-propylthiol substrate, the pertinent parameters in the mechanism are 1n (K1) = −11,000 K/T + 33.6, where K1 is dimensionless, 1n (K2) = 4270 K/T −10.5, where K2 is in 1/mol, 1n (k2) = 30.0 − 5260 K/T, and 1n (k2) = 26.8 − 6190 K/T, where k1 and k2 are in 1/(mol min).}, number={12}, journal={CHEMICAL ENGINEERING SCIENCE}, author={LIM, PK and GILES, DW and CHA, JA}, year={1986}, pages={3141–3153} }
 @misc{cha_lim_1984, title={A NOVEL SEPARATION TECHNIQUE USING AEROBIC COUPLING REACTIONS}, volume={39}, ISSN={["0009-2509"]}, DOI={10.1016/0009-2509(84)80012-3}, abstractNote={Utilisation de reactions de couplage aerobies pour extraire des substances solubles de solutions: de l'air ou de l'oxygene sert de catalyseur pour convertir les especes solubles en produits de couplage insolubles qui peuvent alors etre facilement elimines par sedimentation ou filtration. Resultats experimentaux}, number={10}, journal={CHEMICAL ENGINEERING SCIENCE}, author={CHA, JA and LIM, PK}, year={1984}, pages={1522–1524} }
 @article{lim_fagg_1984, title={MANGANESE-CATALYZED AUTOXIDATION OF AQUEOUS HYDRAZINE - KINETICS, MECHANISM, AND CATALYST INHIBITOR CONVERSION}, volume={88}, ISSN={["0022-3654"]}, DOI={10.1021/j150650a022}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTManganese-catalyzed autoxidation of aqueous hydrazine: kinetics, mechanism, and catalyst-inhibitor conversionPhooi K. Lim and Barry S. FaggCite this: J. Phys. Chem. 1984, 88, 6, 1136–1140Publication Date (Print):March 1, 1984Publication History Published online1 May 2002Published inissue 1 March 1984https://doi.org/10.1021/j150650a022RIGHTS & PERMISSIONSArticle Views172Altmetric-Citations13LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (560 KB) Get e-Alerts}, number={6}, journal={JOURNAL OF PHYSICAL CHEMISTRY}, author={LIM, PK and FAGG, BS}, year={1984}, pages={1136–1140} }
 @article{lim_cha_fagg_1984, title={USE OF MANGANESE(II)-POLYOL COMPLEXES TO ACCELERATE HIGH-PH PEROXIDE OXIDATION REACTIONS}, volume={23}, ISSN={["0196-4313"]}, DOI={10.1021/i100013a006}, abstractNote={Aufgrund kinetischer Daten wird gezeigt, das mit Luftsauerstoff in Gegenwart von Mangan(ll)-Salz-Sorbit-Komplexen bei hohen pH-Werten Oxidationen durchgefuhrt werden konnen, fur die sonst das viel teurere H2O2 verwendet wird.}, number={1}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY FUNDAMENTALS}, author={LIM, PK and CHA, JA and FAGG, BS}, year={1984}, pages={29–33} }
 @article{lim_cha_patel_1983, title={AEROBIC COUPLING OF AQUEOUS PHENOL CATALYZED BY CUPROUS CHLORIDE - BASIS OF A NOVEL DEPHENOLIZATION SCHEME FOR PHENOLIC WASTEWATERS}, volume={22}, ISSN={["0196-4305"]}, DOI={10.1021/i200022a023}, abstractNote={The discovery that cuprous chloride can effect the aerobic coupling of aqueous phenol under mild reaction conditions had led to the proposal of a novel dephenolisation scheme for high-strength phenolic wastewaters. As envisaged, aqueous phenols will be converted aerobically and catalytically into insoluble coupling products which may then be easily separated from the wastewaters. The recovered solid organics may be disposed of as a fuel. The low costs of cuprous chloride and oxygen, the simplicity of the scheme, and the fuel value of the recovered organics make the scheme highly promising. A preliminary study with actual coal gasification wastewater confirms the promising nature of the proposed system.}, number={3}, journal={INDUSTRIAL & ENGINEERING CHEMISTRY PROCESS DESIGN AND DEVELOPMENT}, author={LIM, PK and CHA, JA and PATEL, CP}, year={1983}, pages={477–482} }
 @article{chik_yu_lim_tong_wong_john_1983, title={GAP STATES STUDY OF EVAPORATED SILICON FILMS BEFORE AND AFTER HYDROGENATION}, volume={59-6}, ISSN={["0022-3093"]}, DOI={10.1016/0022-3093(83)90577-x}, abstractNote={The distribution of gap states in evaporated amorphous silicon films before and after hydrogenation is investigated by the space-charge-limited current (SCLC) method. Broad peaks of gap states with density around 3 × 1017 cm−3 eV−1 are observed at energy between 0.73 and 0.53eV below Ec. Hydrogenated samples show an exponential band tail with gap state density decreasing smoothly to about 5 × 1015 cm−3eV−1 around 0.4eV below Ec.}, number={DEC}, journal={JOURNAL OF NON-CRYSTALLINE SOLIDS}, author={CHIK, KP and YU, CK and LIM, PK and TONG, BY and WONG, SK and JOHN, PK}, year={1983}, pages={285–288} }
 @article{huss_lim_eckert_1982, title={OXIDATION OF AQUEOUS SULFUR-DIOXIDE .1. HOMOGENEOUS MANGANESE(II) AND IRON(II) CATALYSIS AT LOW PH}, volume={86}, ISSN={["0022-3654"]}, DOI={10.1021/j100218a027}, abstractNote={The kinetics of the homogeneously catalyzed oxidation of aqueous sulfur dioxide solutions was investigated. Of the first-row transition-metal ions, only manganese and iron were found to be catalytically active. The Mn(II)-catalyzed reaction showed no induction period, and the initial rate was described by the following rate expression: d(S(VI))/dt = 10/sup (6.39-4.07I/sup 1/2//(1+I/sup 1/2/))/(Mn(II))/sub 0//sup 2/ + 10/sup (3.48-1.01 I/sup 1/2//(1+/sup 1/2))/(Mn(II))/sub 0/(HSO/sub 3//sup -/). In contrast, the Fe(II)-catalyzed reaction showed induction periods of up to 2 h, and the overall reaction rate following the induction period was described by d(S(VI))/dt = 10/sup (0.79-0.99I/sup 1/2//(1+I/sup 1/2/))/(Fe(II))/sub 0//sup 1/ /sup 16/(HSO/sub 3//sup -/)/sup 0/ /sup 61//((H/sup +/)/sup 1/ /sup 11/(SO/sub 4//sup 2 -/)/sup 0/ /sup 43/) at low oxygen pressures (< 10 bar). Both the Mn(II)- and Fe(II)-catalyzed reactions exhibited negative salt effects with overall Z/sub A/Z/sub B/ = -3.88 and -0.98, respectively. 9 figures.}, number={21}, journal={JOURNAL OF PHYSICAL CHEMISTRY}, author={HUSS, A and LIM, PK and ECKERT, CA}, year={1982}, pages={4224–4228} }
 @article{huss_lim_eckert_1982, title={OXIDATION OF AQUEOUS SULFUR-DIOXIDE .2. HIGH-PRESSURE STUDIES AND PROPOSED REACTION-MECHANISMS}, volume={86}, ISSN={["0022-3654"]}, DOI={10.1021/j100218a028}, abstractNote={High-pressure studies on the Mn(II)- and Fe(II)-catalyzed oxidations of aqueous sulfur dioxide solution were conducted in a specially designed Teflon reactor. The Mn(II)-catalyzed reaction was independent of oxygen concentration over the wide concentration range studied, 0.0003-0.090 M, while the Fe(II)-catalyzed reaction was zero order with respect to oxygen for oxygen concentrations below 0.01 M and exhibits a first-order term for oxygen concentrations above 0.01 M. Activation energies of 24.5 and 31.1 kcal/g-mol were determined for the Mn(II)- and Fe(II)-catalyzed reactions, respectively; and the corresponding activation volumes were 10.6 and 9.9 cm/sup 3//g-mol. Mechanisms consistent with the findings of the two catalyzed reactions are also presented. 6 figures, 3 tables.}, number={21}, journal={JOURNAL OF PHYSICAL CHEMISTRY}, author={HUSS, A and LIM, PK and ECKERT, CA}, year={1982}, pages={4229–4233} }
 @article{lim_huss_eckert_1982, title={OXIDATION OF AQUEOUS SULFUR-DIOXIDE .3. THE EFFECTS OF CHELATING-AGENTS AND PHENOLIC ANTIOXIDANTS}, volume={86}, ISSN={["0022-3654"]}, DOI={10.1021/j100218a029}, abstractNote={The inhibiting effects of chelating agents (1,10-phenanthroline and EDTA) and phenolic antioxidants (phenol, hydroquinone, resorcinol, pyrocatechol, phloroglucinol, and pyrogallol) on the catalyzed oxidations of low- and high-pH aqueous S(IV) solutions were investigated. Both the low-pH Mn(II)- and Fe(II)-catalyzed reactions were inhibited by phenolic antioxidants, with the effect on the Mn(II)-catalyzed reaction being much more pronounced. The chelating agents, on the other hand, had a far greater inhibiting influence on the Fe(II)-catalyzed reaction. The high-pH Cu(II)-catalyzed reaction was markedly inhibited by both chelating agents and antioxidants. The results support our previous conclusion that the previously accepted uncatalyzed oxidations of S(IV) were in fact primarily trace-metal catalyzed. 7 figures.}, number={21}, journal={JOURNAL OF PHYSICAL CHEMISTRY}, author={LIM, PK and HUSS, A and ECKERT, CA}, year={1982}, pages={4233–4237} }