A highly sensitive potentiometric flow injection analysis (FIA) for bromate has been previously proposed by utilizing the detection of a large transient potential change which appears during the reaction of bromate with a Fe(M)-Fe(I1) potential buffer containing bromide. The transient potential has been estimated to be due to bromine as an intermediate of the reaction (1).
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In this paper, in order to confirm the est imated reaction pathway and rate of the reaction (1), the overall reaction rate among bromate, bromide and iron(11) in sulfuric acid solution and reaction rates of each steps ( a ), (b ) and ( c ) were measured by stopped-flow spectrophotometry by following the bromine concentration. The absorbance change at 447 nm was used for the determination of bromine. The absorbance change on addition of bromate to the reagent solution of iron(10 and bromide, showed the formation and decay of bromine, which indicates the successive reactions involving bromine as an intermediate. The rate constants, kFl, 42 and kR for reactions ( a ), (b ) and ( c ), respectively, were determined separately by measuring the concentration change of bromine as function of time. As results, the rates of reactions ( a ), (b ) and ( c ) were expressed by Eq s. (2), (3) and (4), respectively. The rate constants, 141, kF2 and kR were found to be 3.18+0.23, 1.98±0.20 and 4.09±0.15/ / (mols), respectively, in 0.6 M sulfuric acid solution at 25°C. The concentration change of bromine in the overall reaction among bromate, bromide and iron(li)is expressed by Eq. (5), integrating and rearranging Eqs. (2), (3) and (4).
d[Br]dt =kFI [BrO3-] ⋅[Br-]=k, ⋅[Br03-] 2, )d[Br2]/dt. =kF2⋅[Br03-⋅] [Fe2+] = k2⋅[BrO3-] ( 3 )-d[Bra]dt =4, [Br2]⋅; [Fe2+] = k3⋅ [Br2] ( 4)[B ko r]= k 0[Br03]0 {e-k3t_⋅ e-kot}ko=_ (5)
The bromine concentration-time relation observed in above mixed solution was in good agreement with that calculated from Eq. (5) by using kFl, kF2 and kR obtained.

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Hydrous zirconia film was formed on a stainless steel plate by a dip-coating method from the hydrous zirconia sols, which were synthesized by a hydrolysis of zirconium propoxide, zirconium(1V) nitrate oxide and zirconium (IV) chloride oxide. The stable thin fi lms, with the hues of a rainbow, having thickness of 0.3.4.3 pm were obtained. The vibrational absorption spectra were measured by using PR-FTIR technique in the spectral region from 4300 to 220 cm^-1. Two broad absoption bands were observed at about 3400 and 720 cm^-1. The former is assigned to O-H stretching vibration. The latter broad band, which consists of a overlap of three absorption bands having peaks at 750, 680 and 570 cm^-1, is related to the substrate structure. By heating the sample above 300 °C, the band shape of this broad band changed from rounded hump to sharp peak as a result of a increase in particle size of primary particle.
Since n o changes of the intensity, the band position and the band shape in the vibration spectra measured for the films dipped in either a sodium hydroxide (pH 10) or a hydrochloric acid (pH 2) solutions were observed, it is considered that the prepared film is stable to a chemical attack.

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Solid reducing agents for selective catalytic reduction of NO over Mo0₃-TiO₂ ca talyst were investigated. Urea, cianuric acid, meramine, and biuret were examined as the solid reducing agents substitute for NH3. It appeared that the ability of these agents to reduce NO were same as that of NH₃ in the range of 250-450 °C at a space velocity of 120000 h-1.
A mechanism of NO-urea reaction on Mo0_3-TiO₂ catalyst was also investigated. I t was found that urea reacted with NO at a 1: 2 molar ratio in the presence of oxygen and steam, and the reaction was retarded in the absence of oxygen. Urea was completely hydrolized to NH₃ and CO, by steam on the catalyst above 300 °C . It appeared that Mo0₃-TiO₂ catalys t promoted the hydrolysis of urea. From the FT-IR analysis of adsorption species on the catalyst, NH₄⁺ species resulting from the adsorption of NH₃ on Br Onsted acid site was observed after the catalyst was contacted with urea. This species disappeared after the catalyst was contacted with NO. It may be concluded that NO reacts with NH3 adsorbed on Br cbnsted acid site that formed by hydrolysis of urea.

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The effect for the pyrolysis of the ring size of cycl oalkyl group in 1-methylcycloalkyl (substituted phenyl) sulfoxide was investigated using three kinds of the substrates having cyclopentyl, cyclohexyl and cycloheptyl groups.
Taking the rate constant for the cyclo hexyl sulfoxide as a reference substrate (k=1.86 X 10^-4s^-1 in dioxane at 100.0 °C), the reaction rates of the other two substrates were abou t seven times for the 5-membered and thirty six times for the 7-membered, respectively, larger than that of the 6-membered. The mixtures of methylenecycloalkane (exo-olefin)and 1-mehylcycloalkene (endo-olefin) as pyrolytic products were obtained from the substrates. The ratio of olefin isomers, (exo/endo), of the 6-membered substrate was much larger than the others, respective ratio of 5-, 6- and 7-membered ones being 0.04: 4.38: 0.15. The distinguished results for the pyrolysis manner of the 6-membered substrate compared with the others were considered to be due to bring on the steric strain in six-membered ring to get the endo-olefin isomer.
Activation paramet e rs for the cyclohexyl sulfoxides were estimated as Ea=ca.121 kJmol-'and 4, 54-= 1.7 JK^-1mol^-1. Substituent effect on phenyl group in the reference substrate correlated well with Hammett a constants with p value of ca. +0.9 (γ =0.984). The solvent effect on the pyrolysis was not observed as in the pyrolysis of other sulfoxides and sulfilimines. The kinetic isotope effect for p-hydrogen in cyclohexyl group of the referen ce substrate was relatively large (4, 14=4.6). On the basis of these results, it was suggested that the pyrolysis of 1-methycycloalkyl phenyl sulfoxide proceeds via E 1 like mechanism in a transition state.

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Cyclic and acyclic sulfides such as tetrahydrothiophene, diethyl sulfide, etc. catalyzed a nucleophilic substitution reaction of benzyl chloride in an orga nic phase with potassium thiocyanate in an aqueous phase contacting to the organic pha se. This catalytic reaction pnrotecremededs iatea s foslulolfwosn iu: m in stahlte, owrghaincihc trpahnassfeer s a stuol fitdhee reaaqcuteso us witphh aseb entzoy l reaccht lorwidieth ftohrimociyannga te an i ion. Since the sulfides transfer the substrate from an organic phase t o an aqueous phase b y forming ionic intermediates, the catalytic action can be referred to an inverse. In an analogous reaction with poly(chloromethylstyrene) phcaastea-ltyrasnissfer e subesdtiitautteio n polymreearc tionw ithw itha ltihmioitceyda nanteu mbeiro n opfr ocseuelfdoendi o ing routhpse oirsg ainnisco lubplhe, a soeni n, thtbehe ec caouansqetur aeroyut, h ste h interm phase, and accordingly thiocyanate ion is take into the organic phase from the aqueous phase by anion exchange of the sulfonio groups.

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Change in electric conductivity of aqueous solution of boric acid by the addition of a-Dglucose was investigated and it was found that the conductivity increased considerably by the addition of α-D-glucose, and then decreased gradually with time. The decrease in the conductivity was deduced to result from mutarotation of α-D-glucose toβ-D-glucose, which made the amount of the complex formed between α-D-glucose and boric acid lower. Mutarotation rate of α-D-glucose at various concentrations of boric acid was investigated, and the rate was found to increase once, and then decrease with increasing concentration of boric acid, showing a maximum at a certain concentration of boric acid, which was dependent on the concentration of α-D-glucose. On the assumptions that 1) boric acid can form the complex with α-D-glucose alone, 2) oxonium ion produced by the formation of the complex between boric acid and α-D-glucose catalyzes the mutarotation of α-D-glucose, and 3) the α-D-glucose molecules in the complex cannot cause mutarotation, a theoretical equation was derived for the mutarotation rate. The comparison of the values of mutarotation rate calculated using the equation with observed ones, confirmed that the theoretical equation describes approximately well the mutarotation rate of α-D-glucose in boric acid aqueous solution, and the above assumptions were concluded to be acceptable as the first approximation.

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Addition reaction of polymer bearing pendant S-thioester moiety with epox stigated using quaternary onium salts or cesium halides as catalysts. y cAoms posuhnodw n wains inve scheme ( 1), polymers having pendant (S-thioester moieties such as pol acrylate) (PPTM) and poly(S-benzyl thiomethacrylate) (PBTM) we rye( S-pprheepnayrle d tbhyio mteh-eth radical) polymerization of the corresponding monomers. PPTM has higher reactivity than PBTM and poly(phenyl methacrylate) (Table 5). Addition reaction of PPTM with phenyl grloymcididyel eothr er tetr(aPpGhEen)v yelrpyph roosscpmeheoodonetihdul my unudnedr erb hroigmmhii ldde r earcetaaicso tnio tnh e temccopanetdaraliyttiusortnses. uuOssiinnn gg thtceee tsriauobmtuht eyrl a fmlumhoarindde o, niautshm isp a brr oecaecetidoend catalyesst. t catalyFtiucr theramctoivreit, y in it adwdiatiso n fournedac tiotnh at of cePsPiuTmM flwuoitrhid eP-G1E8- cr(oTwnab-6le 8). complex ha s the high

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The epoxidation of a new type polyolefin with pe ndant side chains containing double bonds (poly(ethylene-co-1, 9-decadiene) (PED), O.8-0.9 mol% vinyl group), with t-butyl hydroperoxide (t-BuOOH) or m-chloroperbenzoic acid (m-CPBA) was carried out both under homogeneous and heterogeneous conditions.
Under the homogeneous conditi ons at 90°Cin toluene, 65% of vinyl groups reacted with t-BuOOH, with selectivity to epoxide of 35%. By use of m-CPBA at 90 °Cfor 48 h, 46%of vinyl groups reacted with selectivity to epoxide of 61%. The molecular weight (Mn; 23000, 9300, 4700) of PED did not affect the reactivity of the polymer.
Under heterogeneous conditions, the epoxidation with t-BuOO H did not proceed. On the other hand, m-CPBA epoxidized PED at room temperature under the heterogeneous conditions: at 25 °C for 48 h, 84% of vinyl groups reacted with selectivity to epoxide of 87%. In conclusion, m-CPBA was an effective reagent for the epoxidation of PED in the heterogeneous conditions at room temperature. t Studies on the High-functionaliza tion of Polyolefin by the Chemical Modifications. I.

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The sphering of loofah and its application to aqueous ge l permeation chromatography as a packing material were studied. Loofah spheres were prepared by the sphering of acetylated loofah by means of the suspension and evaporation method, followed by the saponification and the crosslinking with epichlorohydrin. By adjusting the preparation conditions, loofah spheres with the exclusion molecular weight (>2x10⁶) were produced. In addition, the packings with the diameter of 50-100μm exhibit a excellent pressure-resisting property. These favorable properties are due to the molecular characteristics of loofah fiber.

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The surface potential of ionic polymer membrane was affected by absorption of ordor substances (H₂S, NH₃ etc. ). The surface potentail variance caused by ordor substances was enhanced by addition of electron donor (caffeine, 5'-GMP) to ionic polymer and reduced by addition of electron acceptor (procaine, 5'-AMP) (Figs.3, 4).
Addition of p-cyclodextrin to ionic polymer membrane m ade the sensitivity for terpene increased which is one of the species of perfume enlarged (Table 3). This reason can be considered that a terpene molecule is included in β-cyclodextrin but a part of the molecule stickes out of the pore of the β-cyclodextrin, the part interacts with ionic polymer.
Addition of Cu-chlorophyllin to ionic polymer made the sensitivity for ammonima increased (Figs.6, 7). This reason can be considered that ammonia coordinates to the central Cu(II) ion of Cu-chlorophyllin.

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Recently the reasearch of organic ferromagnetism has been attracting much a ttention. In these works, quite often asked question is whether “the ferromagnetic materials” prepared by the researcher contains some trace amount of iron or not. This is unanswerable question in some cases. It is desirable to know, then, if a very trace amount of iron existing as a contamination to the organic substance under investigation determines the final magnetic behavior of the organic ferromagnetic material derived from it. Iron was impregnated into activated carbon from an aqueous solution of Fe(NO₃)3⋅9 H₂0 to the concentration of 0.01, 10%. After evaporating water, this Fe/activated carbon powder was reduced in H₂ atmosphere (10₅ Pa) at 350 °C for 60 min. Magnetization and ESR spectra were measured with the samples thus prepared. IR and reflection spectra were also observed using KBr discs in which activated carbon (with Fe) was diluted with KBr crystal powders at the concentration of 1 mg/150 mg. The results have indicated that iron-ferromagnetism can be observed only when iron concentration exceeds 6, 8%. If iron concentration is below 1%, the type of magnetism observed with Fe/activated carbon is qualitatively identical to that of pure activated carbon. These observations may permit us to say that “too excess caution about iron contamination” is unnecessary or useless when handling with organic ferromagnetic materials.

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Since acid-rain is a very serious problem in environmental chemistry, the characterization of the rainfall and snowfall collected over a wide area is often necessary. The precipitation samples in Yonezawa city from May 1989 to February 1990 (Sample I ) and from May 1990to February 1991 (Sample n) were analyzed concerning pH value, electric conductivity(EC)and concentrattions of several major ions. The pH values of snowfall distributed in the lower range than those of rainfall. The annual mean pH values of both rainfall and snowfall in Sample I were 4.7, and those of rainfall and snowfall in Sample II were 4.8 and 4.7, respectively. In general, the pH values are low in light rain, but sometimes they were high because of the large wind velocity, e. g. typhoon. The concentration ratio of sodium to chloride in precipitation was nearly equal to that of seawater. The EC value of snowfall increased with the increase of average wind velocity. It is therefore presumed that the sea salt is transported by strong winter monsoon from the Sea of Japan. The data of rainfall samples collected in Yonezawa were nearly equal to the background data from Phase-I Study of Acid Precipitation Survey over Japan by Japan Environmental Agency except NH4 and NO3- which were slightly high level.

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t Present address: The Furukawa Electric Co., Ltd.; Yahatakaigantori, Ichihara-shi 290 Japan Effect of metal catalyst (Co) on morphology and growth rate of SiC whiskers from SiO ( g )-CO system was studied at 1420-1580 °C. SiC whiskers grown on Co-added ac tive carbon had small globes on the growth tip, the main component being Co. By the presence of Co on active carbon, length of whisker increased by 2 to 4 times of that in the absence of Co and diameter of whisker increased markedly at low growth temperatures.

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In order to reveal the temperature dependence of the reactivity of monosubstituted phenols nondestructively, the hydrogen-isotope exchange reaction (liquid-solid reaction) between one of three species of methoxyphenols dissoluved in p-xylene and poly(vinyl alcohol)labeled with tritium was observed at 50---90 °C. The rate constants for these materials have been obtained with the A"-McKay plots based on the respective data obtained. The followings have been clarified comparing these rate constants (and the rate constants obtained previously) with each other.1) The reactivity of ο-methoxyphenol is about 3x10¹times that of p-methoxyphenol.2) The temperature dependence of the reaction constant (ρ) for monosubstituted phenol is extremely small.

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The synthetic method of methyl 7-amino-1, 4 a-dimethyloctahydrophenanthrene-1-carboxylate (here after named methyl 13-amino-13-deisopropyldehydroabietate and abbreviated MADA) was highly improved as descrived below.12-Sulfodehydroabietic acid [2]prepared from dehydroabietic acid [1] by the treatment with 98% sulfuric acid was heated with a mixture of potassium bromide and bromine water to give 12-bromodehydroabietic acid, which was then converted to methyl 12-bromodehydroabietate [3] by the reaction with diazomethane. The treatment of [3] with 88% nitric acid gave methyl 12-bromo-13-nitro-13deisopropyldehydroabietate [4] in a moderate yield. MADA was obtained from 4 in a high yield on catalytic hydrogenation with Pd-C in the presence of triethylamine.

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Synthesis of SAPO-n polycrystalline films were studied to get a better und erstanding of c-4ry1s taplo lygcrryoswtathll inep rocefsilsm s ofw eSrAe POo-bnt aine(dT abloen t1h)e. TIetf l wona s slfaobusn. d tAhbato ut S A1P0O, ---5-2, 0%- 1o1f, t-h1e7, s-t3ar4t ina gn d hydrogels was converted to the films. The large differences in the surface morpholog y and tfhile surface Si concentration were observed between the Teflon and the solution sides of the ms obtained. The Teflon side of the films was formed of an aggregate of cr small crystal size as compared with the solution side (Fig.1). The Si/AI ratio ofy stathlse wsoiltuhtion side was larger than that of the Teflon side (Table 2). From these results, it was concluded that during the initial crystallization of SAPO -n the SAPO -n crystals with the lower Si concentration, A1P0-n, are preferentially crystallized on the Teflon slab.

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In order to replace Pb (C₂H₅)₄, which is highly toxic, bis(2, 2, 6, 6-tetramethyl-3, 5-heptanedionato)lead( II ), Pb(dpm)₂ was syntesized as a new source material for preparation of ferroelectric thin filme by MOCVD. Pb(dpm)₂ was characterized with ICP, elemental analysis, TG-DTA, FT-IR, 11-I-NMR, and ¹³C-NMR. Vaporization of Pb (dpm)₂ started at 105°C as the temperature was raised and steep weight loss was observed in the range of 200 to 280 °C. The vaporization of impurities was not found in TG-DTA. The vaporization completed below 300 °C without residue. Pb (dpm)₂ proved to be superior in volatility and purity for the MOCVD source material.

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