The drag coefficients (C_D) were measured for Nylon spheres in the solutions of ultrahigh molecular weight polystyrene ( IK-1500, BK-2500, the Japan Synthetic Rubber Co. ) in benzene over the Reynolds numbers (Re) ranging from 300 to 7000 at 25°. Nylon balls with various diameters (0.233-1.906 cm) were used for drop tests. Effects of shear degradation on the rheological properties of polymer solutions were not observed in the present study. Solutions at concentrations ranging from, 10 to 160 ppm showed substantial reduction of C_D.
 
  The results obtained are as follows: (1) at Re =890 for the IK-1500 solution and Re =1250for the BK-2500 solution, there seems to be no change in C_D; (2) the percent drag reduction of C_D increases with increasing Re; (3) the percent drag reduction at Re =6400 appears to level off above 40 ppm for the IK-1500 solution and above 80 ppm for the BK-2500 solution; (4) the maximum reduction in C_D was about 30% for the both solutions.

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   Department of Forest Products, Faculty of Agriculture, Kyushu University; Hakozaki, Higashi-ku, Fukuoka-shi 812 Japan The zeta potentials of sedimentary particles (clay) were measured in a flat electrophoresis cell in horizontal and lateral arrangements.
   When the cell was mounted horizontally, the distribution curves of electrophoretic velocities of the particles were asymmetrical about the cell center, because the bottom surface charge was changed by the settling of particles, which occurred gradually during the measurement. Therefore, the electroosmotic flow resulted in an asymmetry. Then it is very difficult to make accurate measurements. The larger the differences in electrical: character between cell walls and particles, the greater the errors of experiments became. The zeta potentials (A) obtained from the upper stationary level were always higher than those (B) from the lower one and the A/B ratios occasionally went up to over 4.
   When the cell was mounted laterally, reproducible measurements were carried out in a wide range of particle concentrations. However, if the microscope illumination was given in the ordinary way, even though a light blue heat filter was interposed in the illumination path, it was difficult to measure the electrophoretic velocities of particles because of rapid particles rising due to convection. Then, it became feasible to put a stop to the particles by balancing the particles rising and the particles falling under gravity, namely by covering an appropriate area of the illumination lens with an adiabatic body such as a water tank according to the degree of convective and settling disturbances. The zeta potentials at the two stationary levels were very close to each other.
   The zeta potential should be determined from the mean value of electrophoretic velocities at the two stationary levels obtained from the Komagata's equation or from the velocity that is obtained by substituting the coefficients of the quadratic equation derived from the observed velocities at several levels by the least-squares method into the Mori-Okamoto's equation.

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The dispersibility of hydrophobic carbon black particles in polar organic media and the effect of surfactants on the dispersibility were studied. The dispersibility was investigated for two kinds of carbon black particles (SR, SB-4) possessing different surface polarity in the absence or the presence of an anionic surfactant (AOT) and nonionic surfactant (NP-10) in 2-butanone. The dispersibility was quite different for the two different carbon black particles in the absence of the surfactants Good dispersibility for the system of SB-4 with a strong surface polarity and bad for SR with a weak surface polarity. This behavior is considered to be due to the difference in the nature of the solvation layer on the particle surface which is caused by the difference in surface polarity. The dispersibility of carbon black was quite different under the existence of the two kinds of surfactants. Although the C-potential decreased slightly by the addition of NP-10, it was not adsorbed on carbon black particles and no change in dispersibility was observed. On the other hand, the flocculation of carbon black was accelelated by addition of a small amount of AOT for both kinds of the particles, and even more so for SB-4 which showed a good dispersibility in the absence of AOT. This characteristic flocculation of carbon black in polar organic media in the presence of AOT was considered to be due to the following reasons. The desolvation proceeds on the particle surface due to the adsorption of a part of counter ions (Na⁺) formed by dissociation of AOT in the bulk solution, and which, in turn, causes a sudden decrease in c-potential.

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To examine the applicability of the Benesi method, acid strength distributions of five different preparations of alumina were measured by the Benesi method (Fig.1) and compared with already published data obtained by the ammonia adsorption-heat (AAH) method, the temperature programmed desorption (TPD) method using butylamine as the adsorbent, and the pyridine adsorption IR (IR-Py) method. The amounts measured are 0.2 to 0.4 of those estimated by the AAH method, but a roughly parallel relationship is found both the measurements (Fig.2). Comparing with the TPD method, a similar relationship is also found (Fig.3) and the total amount of the amine desorbed in its decomposed forms (butenes, propylene, and ethylene) is nearly equal to the acid amount measured by the Benesi method (Fig.4). In comparison with the IR-Py method now regarded as most reliable, a good agreement is found between both the acidity measurements (Fig.5). This agreement indicates that the over-estimation of acidity by the Benesi method, which has been pointed out with silica-alumina, is absent with the aluminas. This is possibly due to the alumina being a weaker solid acid than silica-alumina so as to be capable of reversible interaction with butylamine and Hammett indicators. From the results described above, it is concluded that the Benesi method, which is still to be improved in its operational efficiency in regard to over-estimation, is applicable for characterizing such weak solid acids as alumina in acid strength distributions. For qualitative comparison of the acidic properties obtained by various methods, it is significant to consider the effects of molecular size, physisorption, and the strength of bases used.

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Department of Applied Chemistry, Faculty of Engineering Niigata University; Ikarashi, Niigata-shi 950-21 Japan The polarization phenomena of various samples of alkali metal sulfates: consisted of monocomponent and binary-component sulfates in the forms of 1) compound, 2) solid solution, and 3) mixture; were investigated in a DC electric field at 260° under various atmospheric conditions (vacuum, O2, and NH3). It is clear from Fig.5 that the surface electrical conductivity (σ) of each sample was affected by two kinds of polarization phenomena. One occurred immediately after applying a voltage then σ decreased abruptly in the sample which had the lower conductivity, another occurred slowly and the decrease of σ emerged remarkably in the sample which had the higher conductivity. Such polarization phenomena of all samples were most obviously found in vacuum. In O2 flow, σ of a Na2SO4 sample and a O2-pretreated Li2SO4 sample increased initialy (Fig.6). This can be interpreted, in terms of diffusion of O2 into the crystal as a carrier owing to Hedvall effect with the phase transition reaction. In NH3 flow, σ of mono-component samples increased in the order of Li2SO4<K2SO4<Cs2SO4(Fig.7). These facts are considered to result from an addition of electron conductivity caused by the formation of ammonia-complex. The formation of the complex was more easily achieved against the electronegativity of the positive element in the samples. Exceptionally, no polarization phenomenon was observed in a Na2SO4 sample. This suggests that Hedvall effect with the phase transition reaction promoted the formation reaction of ammonia-coinplex which had electron conductivity.

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Central Research Laboratory, Shimadzu Corporation; Nishinokyokuwabaracho, Nakagyo-ku, Kyoto-shi 604 Japan A gel-like glass material was prepared as a carrier for immobilization of enzyme by the hydrolysis of tetraethoxysilane. This material has a considerable amount of silanol group on its surface and can effectively fix many kinds of enzymes rather than the conventional aminoalkyl glass or silica gels. Furthermore, a chemical treatment, which was partially substituting the silanol groups on their surfaces for fluoride, brought an excellent capability as a carrier for immobilization of enzymes. According to the results of surface analyses using SEM and ESCA, it was confirmed that each particulate of the gel-like glass material (120-200 mesh)had a small porous surface and contained covalently bonded oxygen, silicon, fluoride and the silanol groups. _After these particulates were aminosilanized by refluxing for 2 hours at 80°C with aqueous solution of (3-aminopropyl) triethoxysilane (pH 3-4), glucose, oxidase was immobilized on their surfaces by coupling via glutaraldehyde. The activity of the immobilized glucose oxidase was about two times higher than that of the commercial available aminoalkyl glass at the same conditions. The immobilized glucose oxidase, fixed on this material, was able to be used effectively for the glucose determination. It maintained almost the same activities even after the storage of more than five months in 0. lmol⋅dm-3-phosphate buffer solution (pH 7.0) at 4°C.

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Dissolution of MgO into an H₂SO₄-HI acid mixture: was investigated as a constituent reaction of the Mg-S-I thermochemical water splitting cycle.
  MgO (100) single crystals with cubic shape were used to accurately measure the dissolution rates. The single crystal was fixed at the end of a glass rod and dipped in an H₂SO₄-HI acid mixture. The MgO dissolution rate was obtained by the weight loss of the single crytal. Measurements were performed with varying the following conditions: rotation speed of crystal, temperature, (H₂SO₄/HI) ratio, H+ concentration, and extent of reaction of acid mixture. The results were in the following. (i) Initial dissolution rates of MgO into the acid mixture (H₂SO₄: HI=1: 2, 4mol H⁺/kg H2O) showed little dependency on the rotation speed at 70°C and were almost constant above 100rpm. Activation energy obtained from the Arrhenius plot (40-80°C) for the initial rates, ΔE=64.9kJ·mol-1, indicates that the surface reaction is rate controlling. ( ii ) When the acid ratio (H₂SO₄/HI) was larger than O.125 at 4mol H+/kg H2O, the initial rates were found almost constant and equal to the value corresponding to pure H₂SO₄ solution, while they decreased to 60% at pure HI solution side. (iii) As the reaction proceeded, the rates decreased with the decrease in H+ concentration remaining in the solution. This behavior is almost the same as the dependency of the initial dissolution rates on the H⁺ concentration of the fresh acid mixture. (iv) These results were well explained by considering the adsorption of H₂SO₄ and HI on MgO.
  Dissolution experiments for MgO powders with several particle sizes were also carried out by measuring the time requirement for complete dissolution of the powders in a test tube with stirring. The time measured was consistent with the time calculated using the data of single crystals.

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Magnetite was synthesized by heating of 8-Fe0OH suspension containing urea and iron(II)sulfate at 98°C. Brownish-yellow β-Fe0OH gradually changed to black Fe₃O₄ by heating. In this initial process, β-FeOOH decreased, and at the same time Fe₃O₄ and α-Fe0OH increased. But during further heating α-FeOOH decreased as well as β-FeOOH and finally disappeared. The final product was only Fe3O4. The dissolution of β-FeOOH was promoted in the presence of iron(II) ion. Some part of the produced iron(III) ions dissolved were converted to Fe₃O₄ by the reaction with iron(II)ion, and the others formed α-FeOOH by hydrolysis in the presence of sulfate ion. This α-FeOOH was dissolved in the presence of iron(II) ion, and then Fe₃O₄ was formed. The formation of Fe₃O₄ from the reaction between β-FeOOH and iron(II) sulfate required the longer reaction time as compared to the reaction with iron(II) chloride because of the side reaction through an intermediate α-FeOOH.

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A 50ml (1 ml =1 cm³) sample solution containing less than 0.5μg of nitrite ion is placed in a 100 ml beaker and kept at 25°C. One milliliter of p-aminobenzenesulfonamide solution (0.5% in 2 mol⋅dm^-3 HCl), 0.5ml of N-(1-naphthyl)-ethylenediamine dihydrochloride solution (0.1% in 2mol⋅dm^-3 HCl), and 2ml of 4 mol⋅dm^-3 hydrochloric acid are added. After 10min stirring, 3.0 ml of anion exchange resin suspension (Amberlyst A-27, particle size: less than 30μpm, 8.97pequiv. ⋅ ml^-1) and 2.0 ml of cation exchange resin suspension (Amberlyst 15, 15.40, μequiv. ⋅ ml^-1) are added. The mixture is stirred for 10min. During this period, the red colored azo dye is fixed on the cation exchanger and the resin is coagulated bulky with the anion exchanger. The mixed resins are then collected on a filter paper (No.5B) by filtration with suction for preparing a colored thin layer of 17 mm in diameter and about O.3mm in thickness. The thin layer is dipped in 0.2 mol⋅dm^-3 hydrochloric acid for 15 min to stabilize the color developed. The absorbance is measured against a white paper at 555nm and at 670nm where the azo dye has no absorption. The reagent blank value is also obtained and the net absorbance is determined. The calibration curve deviates slightly from the proportionality, the relative standard deviations (n=6) being 2.5% for 0.05 pg of nitrite ion and 1.8% for 0.5 pg. The absorbance for 1. Opg NO₂^- dm^-3 is about O.1: the sensitivity is approximately 100 times that of the conventional solution method using a 1 cm cell. The method is successfully applied to the determination of nitrite in water samples.

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A method has been proposed for the determination of tetrathionate. It is based on the formation of thiosulfate equivalent to tetrathionate by means of its alkaline decompositi on and then the spectrophotometric measurement of an excess iodine as triiodide for the reaction with the thiosulfate, after removing the sulfite and the sulfide yielded by the decomposition of tetrathionate. The recommended procedure is as follows. Place 10ml of a sample solution containing tetrathionate up to 3.7 x 10-4mol/l and 2m1 of 1 mol/l sodium carbonate into a 50ml beaker, and then allow the mixture solution to stand at 40°C for 60 min for driving the alkaline decomposition of tetrathionate to completion. To this mixture, add 6 drops of zinc carbonate hydroxide solution prepared by mixing 1.5% (w/v) sodium carbonate with 1%(w/v) zinc acetate in equal volume ratio, and 2ml of 1mol/l acetic acid. Filter off the precipitate of zinc sulfide formed, wash the precipitate and the filter paper with redistilled water and then transfer the filtrate and the washings into a 50ml volumetric flask. After adding, 1ml of 0.05mol/l formaldehyde solution, allow the mixture to stand for 1min to mask completely the sulfite formed. Then, add 3ml of glacial acetic acid and 4.8m/l of 1.0x10^-3mol/l standard iodate in 0.87mol/l iodide solution. Fill the flask to the mark with redistilled water, and measure the absorbance of iodine-iodide complex against distilled water at 350nm. e absorbance for tetrathionate decreased with an increase in the concentratio n of tetrathionate, but the calibration graph for tetrathionate exhibited a straight line. In 11 results f or a 10ml aliquot of the sample solution containing 2.00/2mol of tetrathionate, the present method gave a mean value of 2.00, μmol of tetrathionate with a relative standard deviation of 0.59%.

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The pulse polarographic behavior of a carcinogenic nitrosamine, 4-(N-nitrosobutylamino)1-butanol (NBBN) in aqueous solutions has been studied. The effects of temperature, mercury pressure, modulation amplitude, and pH have been investigated. The reduction process is complicated and pH-dependent. In acid solution with pH below 4, the slope of potentialpH curve is -123 mV/pH, also the slope being -86 mV/pH in the pH range between 4.5 and 7 (Fig.1). From the dependence of mercury pressure, h_corr on the current, i by normal pulse (NP) mode, the value of log i-log h_corr plot remains near O.68, being diffusion-controlled. In addition, the slope of i-t curve by the first drop polarograph was ca.0.20 the same as the theoretical value of O.192. The relative temperature coefficients of the limiting current at 20°C lie in the range 1 to 2%/°C, corresponding to the diffusion-controlled current. The differential pulse polarographic peak height is proportional to the concentration of NBBN between 2.5 x 10^-7, and 2.75 X 10^-6mol⋅dm^-3. The detection limit for NBBN under the same conditions shown in Fig.5 was 8.64 X 10^-8mol⋅dm^-3 at ΔE=-50 mV. In the artificial sample of human urine added NBBN, the nitrosamine could not be determined directly because of the interference of protein, bacilli, nitrite and so on. Therefore, it is necessary to do cleanup of the sample by use of freeze-dry and/or column chromatogrphic method.

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Effects of zinc, nickel and copper powders, which were placed on the top of gas-chromatographic column, on the elution of zincOn-, nickel(II)- and copper(II)-dialkyldithiocarbamate [M(drdtc)₂] and thiuram sulfides ((R2NCS2)₂, (R₂NCS)₂S) were investigated. It was revealed that the influence of metal powder was intense in the order of copper>nickel>zinc. For example, on zinc powder, [Cu(drdtc)₂] and some parts of thiuram sulfides changed to [Zn-(drdtc)₂], but no changes were recognized in [Ni(drdtc)₂]. On nickel powder, [Cu(drdtc)₂], [Zn(drdtc)₂] and thiuram sulfides changed to [Ni(drdtc)₂]. On the other hand, on copper powder, [M(drdtc)₂] and thiuram sulfides were adsorbed on copper powder and did not elute. The adsorbates on copper powder were extracted with N, N-dimethylformamide, DMF, analysed spectrophotometrically and identified as [Cu(drdtc)₂]. From the results, it may be deduced that in the presence of metal powder, M', a part of thiuram sulfides formed [M'(drdtc)₂], and [M(drdtc)₂] is exchanged to [M'(drdtc)₂] at the temperature of gas chromatograph.

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Several kinds of poly (vinyl alcohol) (PVA) gel beads were prepared from PVA beads by saponification of poly(vinyl acetate) beads, followed by crosslinking with hexamethylene diisocyanate, tolylene diisocyanate, epichlorohydrin (ECH) and by T-ray irradiation, or from aqueous solution of PVA by saponification of poly(vinyl trifluoroacetate), followed by crosslinking with ECH. Adsorption and exclusion of amino acids on PVA gels were examined and the degrees of hydrophobic interactions between gel matrix and sample were measured by eluting alcohols. Adsorption and exclusion of amino acids were hardly observed on PVA gels derived from poly(vinyl trifluoroacetate), but clearly observed on the other PVA gels. The values of partition coefficient of amino acids and the relationship between conversion and intrinsic viscosity suggest that PVA gels derived from poly(vinyl trifluoroacetate) do not contain acid group. Hydrophobic interactions between gel matrix and alcohol on PVA gels crosslinked with epichlorohydrin or Y-ray irradiation were less than that of other gels.

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The racemic structures of (±) -α-methylbenzylamine salts with organic acids have been studied. The organic acids employed were benzenesulfonic acid (BS), p-methylbenzenesulfonic acid (MBS), p-ethylbenezenesulfonic acid (EBS), sulfanilic acid (SU), p-t-butyl. b enzoic acid (TBB) phenoxyacetic acid (PA), isovaleric acid (IVA), pivalic acid (Pe), methacrylic acid (MC), and 2, 2-bis (hydroxymethyl) propionic acid (HMP). It was concluded based on the comparison of the infrared spectra, melting points and solubilities of these (±)-salts with those of the corresponding (-)-salts that the (±)-TBB salt was conglomerate. It was unable to presume the racemic structures of the other (±)-salts by these comparisons. The enthalpies of fusion values (ΔHf) of (±)-BS, MBS, EBS, SU, PA, MC, and HMP salts were higher than those of the (-)-salts. The 4H values of (±)-IVA and PI salts were lower than those of the (-)-salts. However, these (±)-salts were concluded to form racemic compound, since the free energies of formation of racemic compound values (ΔG∅) were negative. The ΔG∅value of the (±)-TBB salt, being conglomerate, was positive. These results were supported by the binary phase diagrams of melting point. The optical resolutions of (±)-TBB salt were carried out in tetrahydrofuran under the conditions of several degrees of supersaturations (112, 122 and 133%) at 20°C. The (±)-TBB salt was able to be resolved by preferential crystallization procedure and the (-)-salt having a high optical purity was obtained.

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Addition of alkyl vinyl ketones [1] to aldehydes [2]in the presence of tertiary phosphine as a catalyst was studied. In the reaction of 1-penten-3-one [1a] with isobutyraldehyde [2d] catalyzed by triphenylphosphine, 5-hydroxy-4-methylene-6-methyl-3-heptanone [3d], an aldol-type adduct, was obtained. The reaction of [1a] with various aldehydes [2a-g]gave 5-alkyl-5-hydroxy-4-methylene-3-pentanone [3a-g] in 55-80% yield. In the reaction of various alkyl vinyl ketone [1b-f] with [2], aldol-type adducts [3h-1] were obtained in good yields. The reaction of [1] with α, α-dialkylacetaldehydes [2] catalyzed by tributylphosphine yielded Michael-type adducts C5[5a-e]. The reactions were considered to proceed through phosphonium betaine intermediates which attack the aldehydes as in the aldol or Michael-type addition.

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In the reaction of unsubstituted azoxybenzene [1] with iron(III) chloride (FeCl3), the yield of 2-hydroxyazobenzene [2] and 4-chloroazobenzene [3] were higher, the larger the amounts of FeCl3. On the other hand, other azoxybenzenes mainly produced azobenzenes with an excess of FeCl3 except 4-chloro-NNO-azoxybenzene [12].4-Methyl-ONN-azoxybenzene [5α]and 4-methyl-NNO-azoxybenzene [5β] in the presence of FeCl3 were interconversible.

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The mechanism of hydrodenitrogenation of aniline on a reduced molybdena-alumina catalyst has been studied. The reaction was carried out in a high pressure flow microreactor at 260340°C, under the total pressure of 50-440 atm, with the weight hourly space velocity of 10h-1and with the hydrogen flow rate of 30 l/h. The main product was cyclohexane with small amounts of cyclohexene, benzene and methylcyclopentane. The percentage of denitrogenation was 31% and 77% at 300°Cand 340°C, respectively. The addition of benzene did not increase the yields of cyclohexene. When cyclohexene was added, 92% of cyclohexene was converted to cyclohexane. Cyclohexylamine was easily denitrogenated to yield cyclohexane under the reaction conditions. Hydrodenitrogenation of aniline can proceed in two parallel pathways: (1) a preferential hydrogenation of aniline followed by denitrogenation to yield cyclohexene and cyclohexane, and (2) a direct denitrogenation of aniline to give benzene. The present hydrodenitrogenation occurred mainly via the former pathway.

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Design and construction of a high pressure micro-flow reactor for investigating coal liquefaction process at high pressures up to 80 MPa and some experimental results are described. The essentials of the micro-flow reactor are composed of two micro-pumps and three spiral stainless steel tubes for preheating, reacting and cooling sections. The running pressure of the reactor was controlled by use of a commercial spring-type safety-valve. Using this reactor, the hydrogen transfer from tetralin to DPPH as a model of coal at 80°C and the reaction of SRC with tetralin at 400°C were investigated at high pressures up to 80 MPa and up to 60MPa, respectively. The rate constants of the hydrogen transfer reaction from tetralin to DPPH were approximately 0.72(atmospheric pressure), 1.25(20 MPa), 1.48(40 MPa) and 1.72l². mol²⋅s^-1 (60 MPa). The analytical results by means of TLC/FID and solvent-extraction method showed that the solvolytic reaction of SRC with tetralin was accelerated with increasing pressure. The extrapolation of the experimental results suggested that the amount of the hexane-soluble products at 100 MPa was about two times larger than that at atmospheric pressure.

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Four N-[2-(alkylamino)]glycine dihydrochlorides [3](alkyl=octyl, decyl, dodecyl, and tetradecyl) have been prepared by the reaction of N-alkylethylenediamines with sodium chloroacetate in acieous methanol at 60°C for 6 h. Compounds [3] are nonhygroscopic, colorless crystals and behave in water as a triprotonic acid, having pKa' values (30°C) of 2.03, 8.74, and 10.36 for the octyl derivative. Compounds [3] are ampholytic surface-active agents. Their CMC values determined by surface tension and by conductivity measurements lay in the range from 0.24 mol/l for the octyl derivative to 0.0030 mol/l for the tetradecyl derivative. A linear relationship between the logarithm of CMC and the number of carbon atoms in the alkyl chain was found. Surface tension at CMC ranged from 32 to 40 dyn/cm. Compounds [3], especially the tetradecyl darivative, had a good antimicrobial activity against Staphylococcus aureus and Escherichia coli, but was far less effective against a fungus, Apergillus oryzae.

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  Various organic compounds, e. g., aldehydes, ketones, carboxylic acids, alcohols, esters, ethers, phenols, and amines were allowed to react with chlorine and chlorine dioxide in water, and the effects of pH, chlorine or chlorine dioxide dosage, and the reaction time were investigated.
   The amount of organic chlorides formed was determined by measuring total organic chloride (TOCl) and purgeable organic chloride (POCl) using a combustion-coulometric method, and chloroform using a gas chromatographic method.
   The following results were obtained: (1) the amounts of TOCl, POCl, and chloroform formed in the reaction with chlorine dioxide were generally much smaller than those in the reaction with chlorine (Table 1 and 2); (2) although pH influenced the formation of organic chlorides remarkablly, its effect depended upon the nature of each organic compound tested (Fig.1 and 2); and (3) in the case of the reaction with chlorine, the amount of chloroform formed increased with increasing initial chlorine concentration; however, in the case of the reactions with chlorine dioxide there existed the optimum concentration of chlorine dioxide which produced the maximum amount of chloroform (Fig.4 and 5).

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From the standpoint of synthesizing reactive polystyrene through functionalyzation, the reaction leading to the elimination of phenyl group from the main chain of polystyrene was investigated by the catalytic degradation of polystyrene in the presence of silica-alumina catalyst. In low temperature region (190-230°C), a remarkable decrease in molecular weight and the formation of benzene was detected. In particular, a high benzene yield in the early stage was noted. From the structural analysis of degraded polystyrene by NMR, it was found that the number of phenyl groups in the main chain sharply decreased. The amount of phenyl groups eliminated was approximately 2-3 moles per 10 monomer units at each temperature. Also, ethylene units were observed to be formed in the degraded polystyrene in the ratio of 3-18 mol%. These values are nearly the same as those for the eliminated phenyl groups under the same conditions. Therefore, as in the case of the copolymer of styrene-ethylene, modefied polystyrene possessing ethylene units in the main chain was synthesized by catalytic degradation in the presence of silica-alumina catalyst.

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Ultraviolet irradiation with a low-pressure mercury lamp led to a decomposition of trihalomethanes, forming CO, CO2, HCl, and HBr in an aqueous solution at room temperature. In the presence of oxygen, CHCl3 decomposed to form CO2 and HCl. The light transmitted by a Vycor filter could not induce this reaction. In contrast to CHCl3, bromo-substituted trihalomethanes such as CHBrCl2, CHBr2Cl and CHBr3 decomposed even in the absence of oxygen. The decomposition rate of these compounds, which was independent of the presence of Vycor filter, was much larger than that of CHCl3 and the products were CO, HCl and HBr. On the basis of stoichiometry, the overall photochemical reactions were expressed by the following equations.

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The main reaction scheme of the H₂O₂ oxidations of dihydroxo(dioxalato)chromate(III)and dihydroxo(dimalonato)chromate(III) in basic media is presumed as follows. Like the oxidations of [Cr(edta)(OH)]^2- and [Cr(hedta)(OH)]^-, the primary reaction forms hydrogenperoxochromium(III), which is oxidized immediately by the coordinated O₂H^- to a Crv intermediate. The formation of the Cr^v intermediate is confirmed by ESR and visible spectroscopy. It is likely that the Crv intermediate is further oxidized to CrO₄^2- by H₂O₂.

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Basicities of methyl-substituted coumarins ([1]-[29]) have been determined by the spectrophotometric method. It was found that the introduction of methyl group at the C-4position increased the basicity, whereas the methyl substitution at the C-3 position gave no effect. Introduction of two methyl groups at both C-3 and C-4 positiions greatly enhanced the basicity. The Hammett relationship between the basicity and ∑σ of methyl substituents in the ben. zene ring was found to hold for 3-methyl, 4-methyl, 3, 4-dimethyl and unsubstituted coumarins. The Huckel MO calculations have been also carried out for these coumarines. The ΔEπ values for the acid-base equilibria and the π-electron densities on the carbonyl oxygen showed fairly well linear correlations with the observed pKa values.

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4-Substituted 3, 5-bis(methoxycarbony1)-2-isoxazoline 2-oxides, cyclic nitronic esters of type [I], have been readily synthesized in reasonable yields by an one-pot reaction of aldehydes with two molar amount of methyl nitroacetate in the presence of diethylamine in a polar aprotic solvent such as N, N-dimethylacetamide (DMA).4-Substituent of [I] comprises o-, m, or p-functionalized phenyl, fused aryl, or heteroaromatic group. Yields and physical properties of newly prepared 2-isoxazoline 2-o, xides, are, summarized in Table 1, while their spectroscopic data are given in Table 2 (IR, UV, MS, and 1H-NMR)as well as Table 3(13C-NMR). This method is found to be widely applicable to the synthesis of such 2-isoxazoline 2-oxides as type [I], which may serve as an useful intermediate for the synthesis of new type of heterocycles through the ring transformation as reported previously by the authors.

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The oxidation of 1, 2, 3, 4-tetrahydronaphthalene(tetralin) by Co (II)-Ce(III)-NE4, Br in the presence of acetic anhydride resulted in the formation of 1: 1 mixture of cis- and trans-1, 4diacetoxytetralin(A, B). Their structures were discussed on the basis of 1H- and 13C-NMR spectral data, and finally the structure of B was determined by single crystal X-ray method (Fig.2). This was the first report of structure determination of both of cis- and trans-1, 4diacetoxytetralin.

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5, 15-Dialkyl-8, 18-dichloro-5, 15-dihydrodiindlo [3, 2-b: 3', 2'-m] triphenodioxazines [4 a-d], trivially named as Carbazole Dioxazine, were prepared by following two steps ofelectrochemical reactions. (a) The cathodic reduction of 9-alkyl-3-nitrocarbazoles [1] in 4.4% H2SO4aq. -acetonitrile at a graphite cathode under nitrogen gave the corresponding amines [2] in 71-91% yields. (b) The anodic oxidation of 2, 5-dichloro-3, 6-bis(9-alkyl-3-carbazolylamino)-1, 4-benzoquinones [3], which were obtained by the reaction of chloranil with ( 2 ), in DMF at 80°C using a graphite anode at constant current afforded preferentially pure [4]in the yields of 71-81%

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The optical resolution of N-acetyl-DL-a-phenylglycine (Ac-DL-Phg) has been achieved with (-)-α-methylbenzylamine in ethanol. The optical purities of both Ac-D- and -L-Phg obtained from the diastereomeric salts were over 90%.

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