bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wavelength sensitivity of the photoinduced reaction in polycarbonate
Authors: Torikai Ayako , Mitsuoka Takuya , Fueki Kenji 
Published: April 2003

AbstractBisphenol A polycarbonate (PC) was irradiated with monochromatic light of wavelengths 260, 280, 300, 320, 340, 400, and 500 nm by use of the Okazaki large spectrograph (OLS). The quantum yield of main‐chain scission (ϕcs), efficiency of photo‐Fries rearrangement (Er), and effects of wavelength on ϕcs and Er were investigated. It was found that photodegradation and photo‐Fries rearrangement of PC took place by the irradiation of 260–300 nm light, but did not by the irradiation at λ ≧ 320 nm. The ϕcs has a maximum value in the case of the irradiation with 260 nm light, while Er was found to have a maximum value by the irradiation of 280 nm light. © 1993 John Wiley & Sons, Inc.
Sequence‐regulated oligomers and polymers by living cationic polymerization. III. Synthesis and reactions of sequence‐regulated oligomers with a polymerizable group
Authors: Minoda Masahiko , Sawamoto Mitsuo , Higashimura Toshinobu 
Published: April 2003

AbstractNew sequence‐regulated macromonomers (3) with a vinyl ether terminal were prepared by the HI/ZnI2‐mediated living cationic polymerization of vinyl ethers: CH3CH(OR1)CH2CH(OR2)C(COOEt)2CH2CH2OCHCH2 (3a: R1 = nBu, R2 = CH2CH2OCOPh; 3b: R1 = iOct, R2 = CH2CH2Cl). The synthesis consisted of three consecutive steps: (i) quantitative addition of hydrogen iodide to the first vinyl ether into an adduct [CH3CH(OR1)l]; (ii) propagation of a second vinyl ether from the adduct in the presence of zinc iodide; and (iii) quenching the resulting AB‐type heterodimeric living intermediate with a carbanion [θC(COOEt)2CH2CH2OCHCH2] carrying a vinyl ether group. The HI/ZnI2‐initiated living cationic polymerization of 3a and 3b yielded narrowly distributed polymers \documentclass{article}\pagestyle{empty}\begin{document}$\left( {\overline {DP}} _{_n } \sim 10 \right)$\end{document} consisting of a poly(vinyl ether) backbone and sequence‐regulated oligomer branches. The terminal vinyl ether function of 3 was also utilized to prepare pentamers and hexamers with controlled sequence of functional vinyl ethers by selective dimerization and chain extension reactions with HI/ZnI2. © 1993 John Wiley & Sons, Inc.
Ionic‐conductivity switching of vinyl malachite green leuconitrile copolymers based on photoinduced carrier generation
Authors: Kimura Keiichi , Kaneshige Masayuki , Tokuhisa Hideo , Yokoyama Masaaki 
Published: April 2003

AbstractCopolymers of bis[4‐(N,N‐dimethylamino)phenyl]‐4‐vinylphenylmethanenitrile (vinyl Malachite Green leuconitrile) with methyl methacrylate or ω‐methoxyoligo(oxyethylene) methacrylate have been synthesized, aiming at designing one‐component‐type organic polymers for photoswitchable ion‐conducting films. The triphenylmethanenitrile copolymers with ω‐methoxyoligo(oxyethylene) methacrylate were found to undergo ionic‐conductivity switching by turning on and off UV light at ambient temperature, owing to their low glass transition temperature. © 1993 John Wiley & Sons, Inc.
Living carbocationic polymerization of isobutyl vinyl ether and the synthesis of poly[isobutylene‐b‐(isobutyl vinyl ether)]
Authors: Lubnin Alexander V. , Kennedy Joseph P. 
Published: April 2003

AbstractThe MeCH(O‐i‐Bu)Cl/TiCl4/MeCONMe2 initiating system was found to induce the rapid living carbocationic polymerization (LC⊕Pzn) of isobutyl vinyl ether (IBuVE) at −100°C. Degradation by dealcoholation which usually accompanies the polymerization of alkyl vinyl ethers by strong Lewis acids is “frozen out” at this low temperature and poly(isobutyl vinyl ether)s (PIBuVEs) with theoretical molecular weights up to ca. 40,000 g/mol (calculated from the initiator/monomer input) and narrow molecular weight distributions (M̄w/M̄n ≤ 1.2) are readily obtained. According to 13C‐NMR spectroscopy, PIBuVEs prepared by living polymerization at −100°C are not stereoregular. The MeCH(O‐i‐Bu)Cl/TiCl4 combination induces the rapid LC⊕Pzn of IBuVE even in the absence of N,N‐dimethylacetamide (DMA). The addition of the common ion salt, n‐Bu4NCl to the latter system retards the polymerization and meaningful kinetic information can be obtained. The kinetic findings have been explained in terms of TiCl4. IBuVE and TiCl4 · IBuVE and TiCl4 · PIBuVE complexes. The HCl (formal initiator)/TiCl4/DMA combination is the first initiating system that can be regarded to induce the LC⊕Pzn of both isobutylene (IB) and IBuVE. Polyisobutylene (PIB)–PIBuVE diblocks were prepared by sequential monomer addition in “one pot” by the 2‐chloro‐2,4,4‐trimethylpentane (TMP‐Cl)/TiCl4/DMA initiating system. Crossover efficiencies are, however, below 35% because the PIB⊕ + IBuVE → PIB‐b‐PIBuVE⊕ crossover is slow. © 1993 John Wiley & Sons, Inc.
Silanes on magnesium chloride studied by solid‐state 29Si‐NMR spectroscopy
Authors: Clayden Nigel J. , Jones Peter J. V. 
Published: April 2003

Abstract29Si cross‐polarisation NMR was used to study the interaction between silanes and MgCl2 when co‐milled. Large changes are seen for the 29Si chemical shift of the silane between the silane in solution and in the solid complex. Interpretation of the differences in chemical shift are hindered by the absence of an adequate semi‐empirical theory. The 29Si chemical shift tensors confirm a strong interaction between the silane and MgCl2. © 1993 John Wiley & Sons, Inc.
Synthesis of a polyolefin–polystyrene graft terpolymer
Authors: Deeken John S. , Farona Michael F. 
Published: April 2003

AbstractA graft polymer was prepared attaching the macromer, polystyrene end‐capped with benzocyclobutene, to the carbon–carbon double bonds in poly‐1‐hexene‐co‐7‐methyl‐1,6‐octadiene through thermally induced Diels–Alder reactions. The branches per backbone were determined by additive molecular weights and NMR spectroscopy to be 0.8, 1.6, and 2.7, for levels of polystyrene of 40, 60, and 80%, respectively. Grafting efficiencies were high, varying from 84–95%. © 1993 John Wiley & Sons, Inc.
Conductivity of crosslinked poly(N‐vinylpyrrolidone) gel film containing surfactant as electrolyte salt
Authors: Tsutsumi Hiromori , Hamamoto Shinji , Matsuda Yoshiharu 
Published: April 2003

AbstractNew polymeric solid electrolyte films, consisting of crosslinked poly(N‐vinylpyrrolidone) (PVPD) as matrix, and surfactant, sodium deoxycholate (NaDC), lithium deoxycholate (LiDC), sodium laulylsulfate (R12OSO3Na), or sodium palmitate (R15COONa) as electrolyte salt, are prepared; their basic structure and conductivity dependence on temperature are reported. The structure of the electrolytes is amorphous. Their conductivity is 3.1 × 10−5 S cm−1 (containing NaDC), 8.42 × 10−6 S cm−1 (LiDC), 2.18 × 10−4 S cm−1 (R12OSO3Na), and 7.27 × 10−5 S cm−1 (R15COONa) at 20°C. Their temperature dependence of the conductivity is similar to that of liquid electrolyte rather than that of usual polymeric solid electrolyte, i.e., the WLF‐type dependence. The values of activation energy of conductivity (Ea) were PVPD, 25.5 kJ mol−1; PVPD/NaDC, 21.4 kJ mol−1; PVPD/LiDC, 25.3 kJ mol−1; PVPD/R12OSO3Na, 17.2 kJ mol−1; PVPD/R15COONa, 18.7 kJ mol−1. © 1993 John Wiley & Sons, Inc.
Enzymatic polyesterification in organic media. II. Enzyme‐catalyzed synthesis of lateral‐substituted aliphatic polyesters and copolyesters
Authors: Knani Dafna , Kohn David H. 
Published: April 2003

AbstractEnzymatic polymerization of hydroxyesters in organic media has been the subject of a previous and ongoing research in our laboratory. As part of that study, four ϵ‐substituted‐ϵ‐hydroxyesters were synthesized, and then polymerized using crude porcine pancreatic lipase (PPL) in n‐hexane. These lateral‐substituted hydroxyesters polymerized enantioselectively to produce optically active oligomers and a resolved optically active unreacted monomer. It was found that with increasing bulkiness of the lateral substituent, in the order Me >Et >Ph, the enzymatic reaction becomes slower, yet the enantioselectivity is higher. The lateral‐substituted hydroxyesters were also copolymerized enzymatically with the more reactive linear methyl ϵ‐hydroxyhexanoate. Optically active copolymers were obtained, higher in molecular weight than the analogous homopolymers. © 1993 John Wiley & Sons, Inc.
Thermotropic liquid crystalline polyamides from polyethyleneglycol bis(4‐carboxyphenyl)ethers
Authors: Higashi Fukuji , Nakajima Kohji , Watabiki Mamoru , Zhang Wen Xiong 
Published: April 2003

AbstractNew thermotropic liquid crystalline polyamides were prepared from polyethyleneglycol bis(4‐carboxyphenyl)ether (PEGn, n = 2, 3, 4) and aromatic diamines by using triphenyl phosphite in pyridine as the condensing agent. Substituted p‐phenylenediamines and 4,4′‐diaminobiphenyls were successfully used; melting points and isotropization temperatures of the polyamides were changed by the kind and number of the substituents. Copolymerization of long chain aliphatic dicarboxylic acids was carried out at the lower melting point of the copolymer. Kink monomers were also incorporated into the polymer backbone. © 1993 John Wiley & Sons, Inc.
Thermotropic copolyamides from polyethyleneglycol bis(4‐carboxyphenyl)ethers with different oxyethylene units
Authors: Zhang Wen Xiong , Higashi Fukuji 
Published: April 2003

AbstractCopolymerizations of polyethyleneglycol bis(4‐carboxyphenyl)ethers (PEGn) with different n values were found to significantly lower the anisotropic transition temperature (Tm) of the copolymers produced, and the thermotropic copolyamides of thermally more stable nematic phases were obtained. The effect was investigated in terms of PEGm/PEGn molar ratios, the number of oxyethylene units, and the even—odd character of the flexible segment. Several modes of copolymerization were carried out to investigate the effect of monomer (PEGn sequence on Tm. By these copolymerizations thermally stable copolyamides even from p‐phenylenic diamines such as methyl‐p‐phenylenediamine and p‐phenylenediamine were obtained. © 1993 John Wiley & Sons, Inc.
Synthesis and characterization of polyethylene film grafted with acrylic acid and diethyleneglycol‐dimethacrylate
Authors: Gineste Jean‐Luc , Garaud Jean‐Luc , Pourcelly Gerald 
Published: April 2003

AbstractAcrylic acid (AA) and diethyleneglycol‐dimethacrylate (DEGDM) are grafted onto 25 μm low‐density radio‐peroxided polyethylene. Monomer content is determined by exchange capacity measurements. Studies of electrical resistance and zero‐current membrane potential allow for the determination of the influence of DEGDM on both the dissociation of grafted AA and the permselectivity of these so‐obtained cation‐exchange membranes. DEGDM, acting as a crosslinking agent, limits the AA degree of grafting, slightly increases the electrical resistance, but contributes to enhance the permselectivity. For example, when these grafted films are immersed in 3M NaCl aqueous solutions, the addition of DEGDM leads to an increase of the transport number of Na+ close to 20%. © 1993 John Wiley & Sons, Inc.
Living cationic polymerization of vinyl ethers by electrophile/lewis acid initiating systems. XII. Phosphoric and phosphinic acids/zinc chloride initiating systems for isobutyl vinyl ether
Authors: Kamigaito Masami , Sawamoto Mitsuo , Higashimura Toshinobu 
Published: April 2003

AbstractPhosphoric and phosphinic acid derivatives (R1R2PO2H; R1, R2 = OPh, OPh; OnBu, OnBu; Ph, Ph; Ph, H) in conjunction with zinc chloride (ZnCl2) led to living cationic polymerization of isobutyl vinyl ether (IBVE) in toluene below 0°C. The number‐average molecular weights (M̄n) of the polymers (M̄n > 2 × 104) were directly proportional to monomer conversion and in excellent agreement with the calculated values assuming that one polymer chain forms per R1R2PO2H molecule. Throughout the reaction, the molecular weight distributions (MWDs) stayed narrow (M̄w/M̄n ⩽ 1.1). A dibasic acid, PhOP (O) (OH)2, coupled with ZnCl2, also induced living cationic polymerization of IBVE where one molecule of the acid generated two living polymer chains. The polymerization by (PhO)2PO2H/ZnCl2 and its model reactions were directly analyzed by 31P and 1H‐NMR spectroscopy. The analysis showed that the acid initially forms the adduct [CH3CH(OiBu)OP(O)(OPh)2], the phosphate linkage of which is in turn activated by ZnCl2 so as to initiate living propagation. The finding thus indicates that (PhO)2PO2H indeed acts as an initiator in the living polymerization. The NMR analysis also suggested that an exchange reaction occurs between the phosphate group at the polymer terminal and the chlorine in ZnCl2. The occurrence of living IBVE polymerization with these various R1R2PO2H/ZnCl2 systems shows that phosphoric and phosphinic acids are another general class of protonic acids which are effective initiators for the living cationic polymerization assisted by Lewis acids. © 1993 John Wiley & Sons, Inc.
New poly(amide‐imide) syntheses. V. Preparation and properties of poly(amide‐imide)s based on the diimide—diacid condensed from 2,2‐bis[4‐(4‐aminophenoxy)phenyl]propane and trimellitic anhydride
Authors: Yang Chin‐Ping , Hsiao Sheng‐Huei , Lin Jiun‐Hung 
Published: April 2003

AbstractA dicarboxylic acid (1) bearing two pre‐formed imide rings, was prepared from the condensation of 2,2‐bis[4‐(4‐aminophenoxy)phenyl]propane and trimellitic anhydride. A new family of poly(amide‐imide)s having inherent viscosities of 0.53–1.68 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide—diacid I with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. All the soluble poly(amide‐imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these poly(amide‐imide)s were in the range of 237–293°C and the 10% weight loss temperatures were above 508°C in nitrogen. © 1993 John Wiley & Sons, Inc.
Photogeneration of polyfunctional amines and novel thermal curing reactions of epoxy resin and polyurethane oligomer using these amines
Authors: Nishikubo Tadatomi , Takehara Eiji , Kameyama Atsushi 
Published: April 2003

AbstractPhotochemical reactions of various blocked polyfunctional amines such as bis(4‐formylaminophenyl)methane (FAPM), bis(4‐acetylaminophenyl)methane (AAPM), bis(4‐benzoylaminophenyl)methane (BAPM), 2,4‐diformylaminotoluene (DFAT), m‐xylene diformamide, and bis[[(2‐nitrobenzyl)oxy]carbonyl]hexane‐1.6‐diamine were carried out to give the corresponding free amines in THF solution, in epoxy resin, or in polyurethane oligomer with terminal isocyanate groups. Photolysis of FAPM and DFAT to produce the corresponding polyfunctional amines such as 4,4'‐methylenedianiline and 2,4‐diaminotoluene proceeded with 80 and 75% conversions, respectively, in THF solution under UV irradiation at 5 h. AAPM and BAPM also produced the corresponding photo‐Fries rearrangement products with 32 and 38% conversions, respectively, under the same irradiation conditions. The photolysis of those compounds also occurred with similar conversions in the epoxy resin and in the polyurethane oligomer under UV irradiation; and the thermal curing reactions of the epoxy resin and the polyurethane oligomer with photogenerated polyfunctional amines proceeded smoothly after heating at 140°C for 2 hrs. © 1993 John Wiley & Sons, Inc.
Polymeric phosphonium salts as a novel class of cationic biocides. IV. Synthesis and antibacterial activity of polymers with phosphonium salts in the main chain
Authors: Kanazawa Akihiko , Ikeda Tomiki , Endo Takeshi 
Published: April 2003

AbstractPolymers with phosphonium salts and different alkyl spacers in the main chain were prepared, and their antibacterial activities against Staphylococcus aureus and Escherichia coli were explored by the viable cell counting method in sterile distilled water. The antibacterial activity of the polymers was found to be higher than that of the corresponding model compounds against each strain, and the effect of the molecular weight on the antibacterial activity was also observed for the compounds with the same spacer length. The antibacterial activity of the polymer samples bonded with different spacer lengths was found to increase with increasing the spacer length against both strains. © 1993 John Wiley & Sons, Inc.
Novel polymeric structures via the chlorination of cis‐1,4‐polybutadiene in the presence of aryl nucleophiles
Authors: Hahn Stephen F. , Dreyfuss M. P. 
Published: April 2003

AbstractThe addition chlorination of cis‐1,4‐polybutadiene in the presence of a variety of aryl nucleophiles resulted in the formation of head‐to‐head poly(vinyl chloride) with pendant aromatic functional groups. Chlorination in methylene chloride solution with benzoic acid gave chlorinated polymers with pendant benzoate esters. Chlorination in the presence of phenol and benzhydrol provided polymers with pendent phenyl and diphenyl methyl ethers, respectively. Acetophenone participated during chlorination to affored polymer with pendant α‐chloroether groups, while benzonitrile gave a polymer with pendant imidoyl chlorides. The extent of participation of these nucleophiles was estimated from elemental analysis and NMR spectral data, and the effect of aryl substitution on density, glass transition temperature, and linear coefficient of thermal expansion was determined. © 1993 John Wiley & Sons, Inc.
New poly(amide‐imide)s syntheses. VII. Preparation and properties of poly(amide‐imide)s derived from 1,5‐bis(4‐aminophenoxy) naphthalene, trimellitic anhydride, and various aromatic diamines
Authors: Yang Chin‐ping , Chen Wen‐tung 
Published: April 2003

AbstractNew bis(phenoxy)naphthalene‐containing poly(amide‐imide)s having an inherent viscosity in the range of 0.62–1.09 dL/g were prepared by the direct polycondensation of 1,5‐bis(4‐trimellitimidophenoxy) naphthalene (I) and various aromatic diamines using triphenyl phosphite and pyridine as condensing agents in N‐methyl‐2‐pyrrolidone (NMP) in the presence of calcium chloride. The diimide‐diacid (I) was prepared by the condensation of 1,5‐bis(4‐aminophenoxy) naphthalene and trimellitic anhydride. Most of the polymers were soluble in aprotic solvents such as NMP and N,N‐dimethylacetamide (DMAc), and afforded transparent, flexible and tough films upon casting from DMAc solutions. Measurements of wide‐angle X‐ray diffraction revealed that those polymers containing p‐phenylene or oxyphenylene groups were characterized as crystalline polymers. Tensile strength and initial moduli of the polymer films ranged from 61–86 MPa and 1.83–2.21 GPa, respectively. Glass transition temperatures of the polymers were in the range of 231–340°C. The melting points of the crystalline polymers ranged from 375–430°C. The 10% weight loss temperatures were above 512°C in nitrogen and 481°C in air. © 1993 John Wiley & Sons, Inc.
Novel polyaddition catalyzed by transition metals. II. Synthesis of polysulfones using polyaddition of arenedisulfonyl chlorides to diethynyl compounds catalyzed by cuprous chloride
Authors: Lim Jong‐chan , Suzuki Masato , Saegusa Takeo 
Published: April 2003

AbstractCuCl‐catalyzed polyaddition of arenedisulfonyl chloride to diethynyl compound was performed to produce polysulfones consisting of sulfonyl groups between arenylene and chlorovinylene groups. The polyaddition proceeded via both trans and cis addition, whose proportion was affected by the polarity of the reaction medium, the presence of triethylamine · HCl salt, and the nature of the monomer. © 1993 John Wiley & Sons, Inc.
Regioselective hydrosilations. III. The synthesis and polymerization of ambifunctional silicon‐containing epoxy monomers
Authors: Crivello J. V. , Bi Daoshen 
Published: April 2003

AbstractSilicon‐containing epoxide compounds bearing Si  H groups can be readily prepared in high yields by the regioselective rhodium‐catalyzed monohydrosilation of α,ω‐dihydrogen functional siloxanes and silanes with vinyl epoxides. The remaining Si  H groups in these compounds can be further selectively hydrosilated with unsaturated epoxides to give a series of unique ambifunctional monomers containing two different epoxide groups in the same molecule. The photopolymerization of these monomers has been studied using analytical techniques including real time infrared spectroscopy and differential scanning photocalorimetry. On photopolymerization, the new monomers yield interesting networks. © 1993 John Wiley & Sons, Inc.
Regioselective hydrosilations. IV. The synthesis and polymerization of monomers containing epoxy and alkoxysilane groups
Authors: Crivello J. V. , Bi Daoshen 
Published: April 2003

AbstractUsing rhodium and platinum catalyzed regioselective hydrosilation, a series of α‐hydrogen‐ω‐epoxy silane and siloxane compounds have been prepared in good yields. These intermediates have been further condensed with vinyltrimethoxysilane in subsequent hydrosilation reactions to prepare an interesting new class of ambifunctional monomers containing both epoxy and trimethoxysilane groups. It was further shown that these same compounds could be synthesized by a simplified “one‐pot” two‐step procedure. An investigation of the simultaneous cationic ring‐opening polymerization of the epoxy groups and the acid‐catalyzed condensation of the trimethoxysilyl groups was carried out. © 1993 John Wiley & Sons, Inc.
Macromolecular synthesis from saccharic lactones. Ring‐opening polyaddition of D‐glucaro‐ and D‐mannaro‐1,4:6,3‐dilactones with alkylenediamines
Authors: Hashimoto Kazuhiko , Wibullucksanakul Sirinat , Matsuura Mitsuyasu , Okada Masahiko 
Published: April 2003

AbstractRing‐opening polyaddition of a saccharic acid dilactone prepared from D‐glucose, D‐glucaro‐1,4 : 6,3‐dilactone, with several alkylenediamines proceeded at room temperature with no catalyst. The resulting new polyamides carrying many pendant hydroxyl groups, poly(alkylene D‐glucaramide)s, were more amorphous and hydrophilic than the corresponding nylons having no hydroxyl groups, and were hydrolyzed more easily than the latter in an acidic condition. The ring‐opening ability of D‐mannaro‐1,4:6,3‐dilactone, which was another saccharic acid dilactone obtained from D‐mannitol, was found to be lower than that of the D‐glucaric analogue. © 1993 John Wiley & Sons, Inc.
The synthesis of a precursor of polybenzimidazole (PBI) and blends with polyamic acid (PAA)
Authors: Kim S. H. , Pearce Eli M. , Kwei T. K. 
Published: April 2003

AbstractThe precursor of polybenzimidazole (PBI), poly(3,3′‐diamino‐4,4′‐benzidine isophthalamide) (PDABI), was synthesized from poly(3,3′‐dinitro‐4,4′‐benzidine isophthalamide) (PDNBI) by reduction. With increasing temperature, the NH2 moiety which was protected by SnCl5−1 could cyclize and form PBI. Blends with polyamic acid (LaRC‐TPI) were prepared. Clear blend films were prepared at up to 400°C. The IR spectra displayed shifts in the NH stretching band, thereby providing evidence for specific interactions related to the miscibility of their cured blends. © 1993 John Wiley & Sons, Inc.
Graft copolymerization of methyl acrylate onto potato starch initiated by ceric ammonium nitrate
Authors: Liu Mingzhu , Cheng Rongshi , Wu Jingjia , Ma Cheng 
Published: April 2003

AbstractA study was made of the ceric ammonium nitrate (CAN) initiated graft copolymerization of methyl acrylate (MA) onto potato starch. The variables affecting the graft were investigated. The optimums have been obtained; they are the concentrations of MA, CAN, and nitric acid (HNO3) (1.08, 5.0 × 10−3, and 0.081 mol/L, respectively). The reaction temperature is ca. 50°C and the reaction time is 2 h. The molecular weight of grafted poly(methylacrylate) has been determined. On the basis of experimental results, the mechanism of grafting has been explored, a new kinetic equation of the graft copolymerization is established: Rp = Kkd [STOH] [Ce4+] + Kkpkd/kt[STOH][M], where K, kd, kp, and kt are constants. The equation fits the results of experiments. © 1993 John Wiley & Sons, Inc.