Water photolysis by a photoelectrochemical cell using a spinach chloroplasts-methyl viologen system as a photoanode was investigated. The characteristics of the photoanode were studied initially by the effects of additions to the anolyte on the rise curve of the photoanodic current, the action spectrum of the photoanodic current and the potential-current curves of the photoanode. The photoanodic current observed was attributable to oxidation of the reduced form of methyl viologen, which was formed by the chloroplasts irradiated, on an SnO₂, optic ally transparent electrode (SnO₂, OTE). It was found that methyl viologen functioned as e lectron carrier between chloroplasts and SnO₂OTE.
Secondly, in order to elucidate the optimization for the system, the effects of the additions on the charge of the photoanodic current as well as the characteristics of a sandwich-typ e cell were studied. It was found that the use of the sandwich-type cell and the addition of D-glucos e, glucose oxidase and ethanol to the anolyte were effective for increasing the photoanodic current.
Finally, on the basis of the characteristics of a large sandwich-type cell and the chloro p lastsmethyl viologen photoanode and the Pourbaix pH-potential diagram, the photoelect rochemical cell, of which the catholyte consisted of H₂SO₄ solution, was constructed.
The gas, which evolved on the smooth platinum cathode, was identified as hydrogen from the measurements of the potential on the cathode and the charge of the photocurrent as well as from analysis by a gas chromatography. It is concluded that water photolysis was established by the photoelectrochemical cell consisted of the chloroplasts-methyl viologen system.

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Midorigaoka, Ikeda-shi 563 Japan Mischmetal (Mm)-nickel-chromium alloys MmNi_5-yCr_y, (y= 0.5∼1.0) have been found to have the same hexagonal structure as those of LaNi₅ and MmNi₅. They react readily with hydrogen to form hydrides of MmNi_4.5Cr_0.5H_6.3, MmNi_4.25Cr_0.75H_5.2 and MmNi_4.0Cr_1.0H_3.9(hydrogen content: 1.4, 1.2, O.9 wt%) under 60 atm hydrogen pressure at room temperature. The pressurecomposition isotherms for MmNi_5-yCr_y (y=O.5, 0.7 5, 1.0 )-H system at 20°C are shown in Fig.5. The value of log P becomes lower than the value for MmNi₅ hydride. The plateau slope of the isotherm of MmNi_5-y, Cr_y-H system remains reasonably flat and the dissociation pressures of these hydrides are almost same but the width of the plateau decreases with increasing y.
The stand ard enthalpy change in hydride formation of MmNi_4.5, Cr_0.5, is given -6.1 k cal/mol H₂and the dissociation pressure at 20°C yields 4.8 atm. The temperature dependence of desorption rate for the MmNi_4.5Cr_0.5-H system is shown in Fig.9. A value of 4.7∼5.8 kcal/mol is obtained for the apparent activation energy of hydrogen desorption; this value is smaller than those of LaNi₅, MmNi₅ and MmNi_4.5Mn_0.5 (12, 8.6, 5.6∼6.9 kcal/mol, respectively) and is larger than that of MmNi_4.5, Al_0.5, (2.1∼4.3 kca.l/mol).
The hydrogen absorption cyclic test for MrnNi_4.5Cr_0.5, has been carried out. Fig.10 shows that an absorption capacity of hydrogen of the alloy after 500 trials was 87% of its maximum absorption capacity obtained in this cyclic test.

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The reactions between ZrP₂O₇and K₂CO₃and between ZrP₂O₇and Rb₂CO₃have been studied in the range of 10 to 60 m ol% M₂CO₃( M =K or Rb). All the mixtures were heated at 1100°C for 24 h in air. In the ZrP₂O₇-K₂CO₃ system, the samples containing 30 and 50 mol% K₂CO₃were also heated at elevated temperatures up to 1300°C(heating rate: 10°C⋅min^-1). After the reactions had completed, the samples were quenched to room temperature and subjected to X-ray diffractometry.
The reaction products of both systems were crystalline Ma, (PO₄)₂, M₂Zr( PO₄)₂, ZrO₂ (monoclinic), and amorphous M₂O-P₂O₅. In addition to them, an unknown crystral phase was formed in the reactions of the ZrP₂O₇-K₂CO₃ system. It seems that the unknown phase consists of M₂O-P₂O₅ composition. The X-ray diffraction pattern of the crystalline M₂Zr( PO₄)₂ was accordant with that of M₂Zr(PO₄)₂ reported by Allulli et al. The double phosphate MZr₂( PO₄) was formed in the range from 0 to 50 mol% M₂CO₃a nd M₂Zr( PO₄)₂ in the range from 30 to 60 mol% M₂CO₃. The single phase of MZr₂(PO₄)₃ was yielded at 30 mol% M₂CO₃and the single phase of M₂Zr (PO₄)₂ at 50 mol% M₂CO₃.

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Continuous cobalt ferrite thin films which have a thickness of 0.44, μm and a mean grain size of 0.33 μm were prepared by a solid state reaction between cobalt monoxide and magnetite thin films at a relatively low temperature of 400°C. The ferrite films were uniform and transparent, and no macroscopic defect was found on the surfaces. The magnetic coercive forces of the films were relatively high, and the value changed from 1.5 kOe to 50 kOe by heating the films at 300°C in different oxygen pressures. The distributions of cobalt content in the ferrite films were measured by means of Auger electron spectroscopy. The diffusion coefficient of the cobalt ions in the thin films at the reaction temperature was estimated using the distribution curve. The obtained value was about 10^-15cm²/s. By comparing the result with the reported cobalt diffusivity in cobalt ferrite single crystals, it is concluded that the thin film reaction is substantially promoted by a mass transport process through the grain boundaries.

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The solubility of dithionates of metal (II) amine complexes ([M^II(amine)n]S₂O₆: M=Ni, Cu, Zn, Cd; amine=en, pn, dien; n=2, 3) in aqueous sodium chloride. solutions (0∼1.552 mol/kg-H₂O) was measured at the temperature range of 0.4∼70°C. The complexes [M^II(amine), n]S₂O₆ were slightly soluble in aqueous solution. The sokbility of these complexes increased to some extent with the increase of solution temperature and concentration of coexisting sodium chloride, and with decreasing pH values. The solubility of the complex salt [Zn^II(en)₃]S₂O₆, however, gave only a minimum value at pH 10.3. The parameters of Asp, a, b, c and d in the equations ( 1 ) and ( 2 ) were determined for the individual complex salt
log K_sp=log K_sp^o+8S√I/(1+A_sp√I)
(1)log K_sp^o=a+b log T+c/T+dT(2)

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Thermal decomposition under both dynamic temperature conditions and isothermal conditions at 235 and 240°C, and hydrolysis by using H₂SO₄, solution (0.4 25∼17.1 mol/kg-H₂O, 3 0-95°C)and NaOH solution (2.1 9∼12.0 m olfkg-H₂O, 140-150°C) of the complex salts [M^II ( amine)n ]. (M=Ni, Cu, Zn, Cd; amine=en, pn, dien; n=2, 3) were carried out. Sim ultaneous thermal decomposition to form SO₂ and amine occured for these complexes at 160-275°C. However, a part of amine also decomposed into black substances indistinguishable by prolonged heating. Decomposition of dithionate proceeded after neutralization of amine in acid solution. The rate of acid hydrolysis of dithionate ion was first order to the concentrations of h ydrogen ion and dithionate ion. On the other hand, alkali mole ratio more than 4 was n e eded to decompose dithionate ion perfectly in alkaline solution. The complex salts [Zn^II(amine)n]S₂O₆ evolved only amines without decomposing dithionate ion with alkali mole ratio less than 2.

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The sintering behavior and mechanical properties of the MgO doped Al₂O₃-Cr₂O₃ solid solution (MgO =0.7mol%; Cr₂O₃/( Al₂O₃+ Cr₂O₃) = 0, 5, 10, 20, 50, 100 mol%) were studied in two different partial pressures of oxygen (P_O2= 10^-11 and 2 × 10^-1atm) at 1500-1700°C .
The sintering behaviors at both P_O2 were the same in the specime ns with low chromia content (0, 5, 10 mol%) (Fig.2 and 4), and the final densities were over 95% (Fig.6). The magnesia accelerated the sintering rate of the specimens with low chromia content comparing with that of no MgO doped specimens. In chromia rich specimens (20, 50, 100 mol%), the P_O2 affected the sintering behavior significantly. In P_O2= 2 × 10^-1atm the densification process was obstructed, and the specimens with higher chromia 4content had the lower final density. While in P_O2=10^-11 atm, the sintering rate was higher and final density increased. This difference was explained by the vaporization of chromia. When over-fired, the bending strength of the specimens without MgO decreased significantly with sintering time however, the addition of MgO inhibited the exaggerated grain growth and the bending strength increased with tim e(Fig.3 and 5). The, effects of MgO addition were especially remarkable in the specimen with low chromia content. The maximum bending strength (46 kg/mm²) was achieved in the 5 mol % Cr₂O₃ specimen fired, at 1600°C, 1 h in air.
The bending strength of specimens sinter ed in P_O2=10^-11atm at 1600°C decreased significantly in some cases. In these cases, the exaggerated grain growth was observed in the surface region which was caused by the evaporation of MgO from specimen surface.

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Low temperature pyrolytic carbon (LTPC) was allowed to deposit from nine kinds of chlorinated compounds of ethylene and ethane on the graphite substrate heated at 700, 900 and 1100°C with an induction furnace. These chlorinated compounds were classified into three groups from the relationship between their deposition temperature and deposition rate by. weight. The first group consisted of cis-1, 2-dichloroethylene, trans-1, 2-dichloroethylene and 1, 1, 27-trichloroethane and the second included 1, 1-dichloroethylene, 1, 1, 2-trichloroethylene, and 1, 1, 1-trichloroethane. When these chlorinated compounds with the Clal (atomic ratio) =1 were used as source materials, the deposited LTPCs had a low crystallinity, a high adhesive strength between LTPC and graphite substrate, and a large deposition rate at 700°C. On the other hand, vinyl chloride, 1, 1-dichloroethane and 1, 2-dichloroethane were classified into the third group, of which deposition rate of LTPC was rather low at 700°C while it increased rapidly at 1100°C. The deposition behavior of benzene used as a reference source was similar to that of the third group.
The LTPCs prepared from the third group compounds had a higher crystallinity and a lower adhesive strength than those on the LTPCs from the first and second groups. The initial thermal reaction of these chlorinated compounds is dehydrochloride reaction. In the cases of the first and the second source groups, it was found that chlorine atoms still remained in dimers and trimers formed by the initial dehydrochloride reactions, while the intermediate species containing no chlorine atoms were formed from the third group. It is therefore reasonably presumed that the compositions of intermediate species are responsible for these deposition behavior and properties of LTPC. This presumption is also supported by the fact that the deposition behavior of benzene is the same as that of the third source group.

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Photoacoustic spectroscopy (PAS) was applied to the determination of microamounts of nickel(II) and palladium (II) after separating them as dirnethylglyoxime complexes from other 14 metal ions by the ring oven technique. An aliquot of sample solution, 4 mm3, was dropped on the center of the Toyo No.51 A filter paper, and the photoacoustic (PA)intensity was measured in values relative to a standard black substance (sample/black filter paper-blank). Toyo flack filter paper, No.131-B, was the best among the black substan ces (Carbon black powder, active carbon pad, water paint and so on), and could be handled easily. An absorption maximum appeared at 522.0 nm for nickle-dimethylglyoxime complex, and at 470.0 nm for palladium-dimethylglyoxime complex. Determinations of nickel (II)and palladium (II) were made by measuring the PA intensity at 522.0 nm and 470.0 nm, respectively. The PA intensity was plotted against the amount of each metal ions. When a concentrated solution of nickel or palladium ion was dropped on a filter paper, the PA intensity deviated downwards. The relationship between the PA intensity and amount of metal ion could be expressed by a simple equation similar to that of Beer's law. The equation was expressed as At=-log (1-Si/Sb), where At is absorbancy, Si is photoacoustic signal of sample, and Sb is photoacoustic signal of black filter paper. The calibration curves were obtained by using the equation. Determination ranges of nickle (II) was from 0.1 to 3.5 μg, and that of palladium (II) was from 0.2 to 9.5 μg. The coefficients of variation obtained for ten samples was ±2%.

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2- (2-Thiazolylazo)-4-methylphenol (TAC) reacts sensitively with iron (II) to form a waterinsoluble brown complex which can be extracted by many organic solvents. The complex extracted with chloroform is stable for 24 h and shows the characteristic absorption maxima at 527, 628 and 762 nm. The optimum pH for iron extraction lies between 4.8∼10.0 and the calibration curve obeys the Beer's law over the range from 0 to 50 μg/10 ml of iron at 762 nm. The molar absorption coefficient and the sensitivity are 1.37×10⁴l⋅mol^-1⋅cm^-1and 4.08 ng Fecm^-2 for log(Io/I) =0.001, respectively. The molar ratio of iron to TAC in the chelate is found to be 1: 2 and the logarithmic extraction constant is determined to be 2.70±0.22. As the present method utilizes the specific absorption of iron (II) complex, the presence of many ions can be tolerated. It was applied to the determination of traces of iron dissolved in river water and synthetic mixtures with a satisfactory result. The method for the simultanious determination of iron and nickel was also proposed.

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Action of nitric acid (d=1.5) upon bis (pentamethylbenzyl) selenide in cold dichloromethane results in a reductive cleavage of the carbon-selenium bond, giving pentamethylbenzyl nitrate and elemental selenium in nearly quantitative yield. By similar treatment, bis (p-chloro- and p-nitrobenzyl) selenides suffer no bond cleavage but are easily oxidized to the corresponding selenoxides; no ring nitration is observed. Reaction of unsubstituted dibenzyl selenide with nitric acid affords a nitrate of the expected selenoxide as a water-soluble crystalline solid. A marked effect of ring substituents on the reaction modes of dibenzyl selenides has been investigated and a possible mechanism is suggested for the reductive cleavage with nitric acid of bis (polymethylated benzyl) selenides.

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2-Alkyl-2-cyclopentenones [5] were synthesized in four steps from 2-cyclopentenone [1]as described in scheme 1.
Compound [1] was epoxidized in dichloromethane with hydrog en peroxide to 2, 3-epoxycyclopentanone [2] (91% yield) which then reacted with alkylmagnesium bromides in tetrahydro furan below -40°C to give 1-alkyl-2, 3-epoxycyclopentanols [3] selectively (85∼86% yield). Teh epoxide ring of compound [3] was opened by reaction with carbonyl compounds, such as acetone to give 1, 3-dioxolane rings (86%yield). By treatment of the products thus obtained with an aquseous mineral acid, the mixture of [5] and 2-alkylidenecyclopentanones [5'] were obtained. When a 1-butanol-hydrochloric acid solution was used instead of an aqueous mineral acid, [5] was obtained selectively in 83∼85% yield. Overall yields of 2-hexy1-2-cyclopentenone ap, 2-pentyl-2-cyclopentenone[5a], 2-butyl-2-cyclopentenone [5b] and 2-butyl-2-cyclopentenone [5c]from [1] were 57, 57 and 55%, respectively.

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Long-chain alkylbenzenes (alkyl: C₄∼C₁₄) were chloromethylated at 70∼75°C by passing hydrogen chloride for 6∼7h in the presence of paraformaldehyde, zinc chloride and acetic acid. Long-chain alkylbenzyl chlorides were obtaind in good yields (60∼75%) and the chloromethyl derivatives were transformed into the corresponding alkyltoluenes by hydrogenolysis. The isomer contents of the resulting products were examined by infrared spectrometry (IR) and gas-liquid chlomatography (GC).
The analytical results sho wed that the para-substituted compounds (73∼83%) increased with the increase of the length of alkyl chains (C₄∼C₁₄), whereas the ortho compounds (24∼15%)decreased. The meta compounds were formed in small amounts (2.8∼1.9%) and decreased slightly with the increase of the chain length. Determination of o-, m- and p-alkyltoluenes by IR was carried out with fair accuracy by using the homologues with other alkyl chain as a standard, even when their standard substances are not available.

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2, 2-Dimethyl-4-chromanone derivatives ([1], [2], [4], [5], [7], [8], [12], [13], and ) bearing an acetoxyl or a benzoyloxyl substituent peri to the carbonyl group were c o[1n5-]verted directly into the 2, 2-dimethyl-5-chromanol derivatives ([3], [6], [9], [14], and ) by the reduction with sodium borohydride under mild conditions in ethanol. The 5- chromanol [16], was transformed to tetrahydrofranklinone via acetylation of the methyl ether [17].

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Dehydration of pyromellitic acid (PMA) to pyromellitic dianhydride (PMDA) was studied in acetic acid and benzene. In an acetic acid solution, PMA was dehydrated reversibly and succesively (Fig.4) as follows:
PMA_??_PMMA + H₂O _??_ PMDA + ₂O
On the other hand, the dehydration of PMA in a benzene suspension occurred in the solid phase and the dehydration of PMA to PMMA was the rate determination step:
PMA _??_ PMMA _??_ PMDA
Therefore, pyromellitic monoanhydride (PMMA) could be detected in the dehydration products in acetic acid, but not in benzene (Table 1). The degree of dehydration was increased by the removal of product water from the reaction system in both solvents (Table 2). TGA curves of PMMA and PMA showed that they dehydration of PMMA in air began at 130°C which was 50°C lower than that of PMA (Fig.5).

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Spherulites of poly (γ-methyl L-glutamate) (PMLG) in the α-helical form were grown from bromoform solutions at 295 K after aging at 343 K for various periods. Morphologies and internal structures of the PMLG spherulites depend mainly on the aging period and solution concentration.
The PMLG spherulites were classified into three types (Types A, B and C) based on morphological observation by a polarizing optical microscope under crossed nicols. Type A spherulites with positive optical sign were obtained under the conditions of relatively low concentration (1∼6 wt%) and short aging period (∼1 day). Type A spherulites exhibit extinction rings under a polarizing optical microscopic observation. Type B spherulites with positive optical sign were formed without any extinction rings from solutions of concentration ranging from 5 to 15 wt% after an aging period from one day to about one month. Type C spherulites, exhibiting negative optical sign, were prepared under the conditions of relatively high concentration (8∼12 wt%) and longer aging period than 2 months.
The PMLG spherulites are composed of microfibrils in w hich α-helical chains are arranged parallel to the long axis of microfibrils. The long axis of microfibrils is parallel to the radial direction in Types A and B and perpendicular in Type C spherulites. The bright portion of Type A spherulites is formed from a liquid crystalline phase and the dark one from an isotropic phase. The well ordered microfibrils of Type B spherulites are formed from molecular clusters in liquid crystals. The small angle light scattering pattern of the molecular clusters becomes more apparent with an increase of aging time. Longitudinal axes of the molecular clusters change from tangential direction to radial one at the interface of the Type B spherulites, possibly due to the geometrical anisotropy of microfibrils. Type C spherulites were crystallized from the solution containing molecular clusters composed of well fractionated PMLG during aging longer than 2 months. Extinction rings of Type C spherulites may arise from helical twist of the longitudinal axes of microfibrils along the radial direction.

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Silicic acid, prepared by sodium metasilicate and hydrochloric acid, was extracted from an aqueous solution by means of organic solvents. The extraction with tetrahydrofuran (THF)was most effective. The amount of silicic acid extracted into THF increased with an increase in the concentration of hydrochloric acid in the solution.
Silylation of extracted silicic acid by trimethylchl orosilane at room temperature gave silylates with molecular weights of about 1900. The infrared measurement of the relative degree of silylation of the silylates indicated that partially or fully silylated siloxanes were formed depending on the molar ratio of trimethylchlorosilane. Possible structures of the silylates were indicated. When the silylates with a low degree of silylation were heated under reduced pressure, a polysiloxane was obtained with a molecular weight which was nearly three times higher than that before heating.

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Expressions describing the diffusion of dye in the cylindrical film roll were derived by the integral and Galerkin techniques, and two methods ( I and II) to determine the diffusion coefficient from the dye concentration profile were proposed. Method I is an improvement of the Sekido and Mastui's method. Method II is a new approximate method to obtain th e diff usion coefficient of dye in the cylindrical film roll. It was shown that both methods gave excellent accuracy in the determination of the diffusion coefficient from the dye concentration profile.

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The rigidity of the poly (spiro[2.4]hepta-4, 6-diene) (PSHD) molecule was investigated by calculations of its conformational energy associated with the main chain and by dynamic viscoelasticity due to the molecular motion in the solid state. The density of PSHD decreases with increasing fraction of the 1, 4 unit (F_{1, 4}) in the random copolymer made of 1, 2 and 1, 4units and is considerably smaller than those of typical polymers, when the occupied volume of the repeat unit is considered. The dependence of the aggregation states of the PSHD molecular chains on F_{1, 4} was investigated by X-ray diffraction and electron microscopy. The heterogeneous amorphous state composed of densely and loosely packed aggregations becomes more homogeneous with an increase of F_{1, 4}. Permeability and diffusion coefficients for gases exhibit the minimum in the vicinity of F_{1, 4} =0.7. These observations can be explained by the complex combining effects of chain packing and heterogeneity with respect to the aggregation states of the molecular chains.

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A new urea electrode capable of making urea determination in the buffered whole blood was described. The electrode was constructed by firmly attaching the expanded poly (tetrafluoroethylene)membrane (pore size 1 μm, thickness 70 μm) impregnated with polyacrylamide gelentrapped urease onto the gas-permeable membrane of an ammonia gas sensing electrode. The urease membrane was mechanically stable and obtained reproducibly with respect to the enzyme layer thickness and the enzymatic activity. At pH= 8.3, the electrode response was inear over the urea concentration range 10^-5∼10^-2 mol/l with the slope of 59 mV/decade and the response times of 10 min, 2∼3 min and 1.5 min for 10^-5 molg, 3x 10^-4 and 10^-2 mol/l urea respectively. The electrode response was shown to be reproducible within 1 mV in the buffered whole blood and stable for at least 1 month (25 samples/day at 18°C). The urea concentrations in the buffered whole blood was determined within 2∼5 min and agreed well with those determined by a conventional method.

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In order to study the removal of arsenic (III) from aqueous solution, the adsorption behavior of arsenic(III) on the chelating resin (RGS-KSH) containing mercapto groups was investigated by batch and column methods. In the batch method, RGS-KSH showed a good affinity for arsenic(III) in the wide range of H⁺ concentrations which were from 6N hydrochloric acid solution to alkaline solution of pH 10, whereas it showed a good affinity for arsenic(V) only at a very high hydrochloric acid concentration. The adsorption of arsenic(III) was not influenced by Na⁺ or Ca²⁺ in the concentration range of 0.05∼2.0 eq/l. In the column method, RGS-KSH exhibited a satisfactory adsorption ability for arsenic(III) under the following conditions: loading solution, As(III) 3mg/l, pH 6.1, space velocity 15^-1 The elution of arsenic (III)adsorbed was accomplished by allowing 1N sodium hydroxide to pass through the column.

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“Resin Spot Test” method was applied to the-detection of a minute amount of U(IV) and U(VI). A few particles of the anion-exchange resin (Dowex 1-X 1 [Cl]) impregnated with arsenazo III were put into a drop of sample solution on a spot plate and a drop of acetic acid solution was added to adjust the pH of the solution to 1∼5. After a while, pale-blue green to dull green color appeared on the surface of the resin particles, while blank test was palepurple color. The colors for U(IV) and U(VI) were similar. The limits of identification for both ions were 0.03 μg, and the dilution limits were 1: 10⁶. The time required for this test was remarkably shortened by heating the system with an infrared lamp.

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“Resin Spot Te st” method was applied to the 'detection of a minute amount of nitrite ion. A drop of sample solution on a white spot plate was mixed with a few particles of the cation exchange resin (Dowex 50 W-X 2 [H]) and a drop of 1% Griess-Romijn reagent was added. Red purple color appeared on the resin particles. The limit of identification was 0.003 μg, and the dilution limit was 1: 10⁷. Several metallic ions, such as Cu (II), Fe (II), Fe (III) ions and S^2- interfered with this test.

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Potassium permanganate was replaced by potassium dichromate in our previously proposed method for colorimetric determination of methanol with chromotropic acid. The est ablished procedure is as follows. To 1.0 ml of the test solution containing 1.5∼30, μg of methanol, add 0.2 ml of a 0.2 w/v% 1-aminoethanol solution, O.2 ml of 1: 1 sulfuric acid, and 0.1 ml of a 1.0% potassium dichromate solution. Allow the mixture to stand at room temperature for 40 min. Add O.1 ml of a 20% sodium sulfite solution to reduce the excess of the dichromate and a 0.2 ml of 2% aqueous chromotropic acid solution. Add slowly 4 ml of 75%sulfuric acid. Heat the mixture in a boiling water bath for 10 min. Upon cooling to room temperature, measure the absorbance at 575 nm against the reagent blank.
The sensitivity for detection was about 29 times higer than that in the absence of 1-amino ethanol, and the detection limit for methanol was 1.5, μg/ml, the molar extinction coefficient being 5.01 × 10³ mol^-1 ⋅ cm^-1 ⋅dm³. The improved sensitization is most plausibly originated from the acceleration effect of the added 1-aminoethanol on the oxidation of methanol to formaldehyde in a potassium dichromate-sulfuric acid solution.

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The reaction of benzenetriols (phloroglucinol [1] pyrogallol [2] and 1, 2, 4-benzenetriol [3]) with 1-chloro-3-methy1-2-butene (prenyl chloride) in the presence of 85% phosphoric acid or metallic sodium was discussed. Methylation of the reaction mixture was carried out with dimethyl sulfate and the products were analyzed by gas chromatography. In the presence of 85% phosphoric acid, 2, 2-dimethylchromans ([4], [6], [8]) were obtained mainly as usual. In the presence of metallic sodium, alkenyltrimethoxybenzene ([5], [7], [9]) were obtained in the yields of 52, 42% and 19%, respectively. Especially in the case of [3], 6, 7dimethoxy-2, 2-dimethylchroman [8] (37% yield) was obtained in a higher yield than [9]. By using the prepurified sodium phenoxide, [5] and [7] could be obtained in fairly good yields (67% and 61%, respectively) in the case of [1] and [2].

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4-Acylisoxazoles [7 b, c, f, h, i] and 4-isoxazolecarboxylates [7 a, e, g, k, l] have been synthesized by the reaction of primary aliphatic nitro compounds with acid chlorides and β-keto esters or 1, 3 =diketones as dipolarophiles. The acylation leads to the formation of nitrile oxides whic h undergo 1, 3-dipolar cycloaddition with olefinic dipolarophiles in situ in aprotic polar solvents, e. g., N, N-dimethylacetamide. When olefins or acetylenes were used as dipolarophiles, (phenylthio)isoxazolinecarboxylates [8a, b] and (phenylthio) isoxazolecarboxylates [9c, d, e] were obtained, respectively, in reasonable yields.

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