In earlier papers the relation, (E_1/2^oxd-E_1/2^red)=k₁^{1, 3}E_ho→1u^UV+k₂, was reported by us, where E_1/2^oxd and _1/2^red, and ^{1, 3}E_ho→1u^UV áre the nonaqueous oxidation and reduction potentials, and HOMO→LUMO type singlet or triplet band energy, respectively. As an extension of t his equation we recently derived the equations, ^{1, 3}E^UV=aF+bR+c and ^{1, 3}E^UV=ασ_i+βσ_π⁺+γσ_π^-+C, focusing our attention on the large difference of the substituent effect on the ground and excited states. F and R are Swain's field and resonance, substituent constants, and Yukawa-Tsuno- Sawada's constants are given by σ_i σ_π⁺ and σ_π^-. These general equations well described the substituent effect on HOMO→LUMO type π-π* bands, n-7r* bands in conjugated and aliphatic systems, intermolecular charge-transfer (CT) bands of EDA complexes, and in-tramolecular CT bands of aromatic N-oxides. In addition, we discussed the application of our equations to the first and second singlet π-π* bands of substituted benzenes, which correspond to the ¹L_b and ¹L_a bands of benzene itself. The first band has been well explained 'by the above equation, but the second band was poorly described. This disagreement may be due to the fact that the contribution of intramolecular CT configurations to the second band is quite dependent on substituents. Therefore, the second band character is not common throughout all the substituents. A molecular orbital examination of these results was presented, and the limitation of the application of our equation was discussed.

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Zeolite Y with SiO₂/Al₂O₃ molar ratios=5.5-6.0, were synthesized from the reaction mixtures whose molar ratio were (2.541-2.943)Na₂O-Al₂O₃-(9.81-13)SiO₂-(104.2-120.4)H₂O, using colloidal silica, silica sol and sodium aluminate solution. The changes in chemical composition of solid and liquid phases on the course of zeolitization were analyzed by XRD, MASNMR, SEM observation, and chemical analyses. After the ageing at 25°C for 24 h, only a small amount of silica reacted with sodium aluminate solution, and the concentration of silica in liquid phase was very low. After the heating at 99.5°C for 1 h, ²⁹Si-MASNMR signals shifted to lower fields, and the concentration of silica species increased up to 1.2-1.6mol/dm³, though the concentration of aluminate ions decreased to 0.01-0.02 mol/dm³. During the induction period, the concentrations in liquid compositions were kept at nearly constant. With decreasing Na₂O/SiO₂ molar ratio of reaction mixture, Na⁺/SiO₂, ratio in liquid phase decreased. When the value of Na⁺/SiO₂, in liquid phase decreased to 0.84 or less during the crystallization, spherulites of chabazite and gmelinite appeared. The changes of ²⁰Si-MASNMR signals seemingly showed the solid-solid transformation mechanism on the formation of zeolite Y. However, the XRD and chemical analyses of solid phases proved the formation of zeolite Y with SiO₂/Al₂O₃= 5.985, from amorphous solid with SiO₂/Al₂O₃=7.0-7.2. These results show the liquid-solid transformation mechanism on th e formation of zeolite Y.

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A simple and accurate method for the determination of selenium in biological samples was investigated by the combustion of samples under a high pressure of oxygen followed by the hydride generation atomic absorption spectrometry. The accurately weighed ground sample less than 1 g is ignited in a Parr 1108 oxygen combustion bomb filled with oxygen to 3 MPa and added with 1 cm3 of water. Ignition normally takes about 1/2 s. The selenium trioxide formed dissolves in water as SeO₄^2-, which is in turn reduced to SeO₃^2- by being boiled in 6 mol dm^-3 hydrochloric acid medium for 3 min. After diluting the above solution to 100cm³ with water, atomic absorption measurement is carried out by using the hydride generation system and quartz cell which is heated in an acetylene-air flame according to the instrumental conditions given in Table 1. The optimum concentrations of sodium tetrahydroborate and hydrochloric acid to produce hydrogen selenide are 0.5% (0.05% NaOH) and above 3.5%, respectively. The method of standard additions was employed to determine selenium contents in natural samples. For NBS Bovine Liver 1577 and 1577a, selenium contents of 1.09 μg g^-1 and 0.66 μg g^-1 were in good agreement with certified values of (1.1±O.1) pg g-i. and (0.71±0.07) μg^-1, respectively. Selenium contents in some other sample s, NIES Mussel and soybeans, were also in good agreement with those obtained by neutron activation analysis as shown in Table 3.

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A method has been developed for the determination of micro amounts of thiosulfate. It is based on the oxidation of thiosulfate by a given excess amount of permanganate in a sulfuric acid medium and on the spectrophotometric measurement of the iodine as triiodide formed by the oxidation of iodide with the excess of permanganate. The recommended procedure is as follows. Pipette 5 ml of 1 mol/l sulfuric acid and 4 ml of 2 x 10^-4 mol/l standard permanganate solution into a 25-ml volumetric flask. To this mixture, add 10 ml of sample solution containing thiosulfate up to 42.0 μg, shake the mixture immediately and vigorously, and allow it to stand for 30 min at temperatures ranging 15-35°C. At this time, 3 mol of thiosulfate consume 4 mol of permanganate as a result of oxidation of thiosulfate by permanganate. Then, add 1 ml of 7.5 mol/l ammonia solution and 1 ml of O.5mol/l iodide solution to the mixture in order to form iodine equivalent to an excess o f permanganate for the thiosulfate. Add 1.4 ml of 1 x 10^-3 mol/l thiosulfate to decrease the absorbance for the iodine (as triiodide) thus formed to an appropriate value; otherwise the reagent blank is too high for the measurement. Measure the absorbance for the iodine (as triiodide) against water at 350 nm within 5 min after the flask was filled to the mark with water. Subtract the permanganate-free reagent blank obtained by a procedure using 4 ml of water instead of 2 x 10^-4 mol/l permanganate and 1.4 ml of water instead of 1 x 10^-3 mol/l thiosulfate from each of the absorbances for thiosulfate and reagent blank, for iodide is susceptible to air-oxidation in an acid medium. The proposed method can be successfully applied to the determination of thiosulfate in the range from 5 x 10^-7 to 3.75 x 10^-5 mol/l (0.6 -42.0 μg of S₂O₃^2- in 10 ml) in hot spring waters.

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The application of a dual flow countercurrent system which entails continuous countercurrent fractional extraction (CFE) is described. Fig.1 shows a schematic design of the CFE method. Five pumps and two glass columns segmented by teflon disks with a 4 mm hole were used. The number of cells per column is 144. The columns were equipped with end caps which contained rotating seals (Fig.2) along with an inlet for one phase, and an outlet for the other phase. The columns were filled with the two-phases solvent, lighter and heavier of carbon tetrachloride: methanol: water (62: 35: 4), then they were fixed at 15° from horizontal and rotated about its longitudinal axis at 100 rpm. The lighter phase is fed to bottom of the column and heavier phase is fed to top of the column simultaneously at 1.00 and 0.60 mi/min each. The sample (Fig.3-(1)) dissolved in the heavier phase (10 g/200 ml) was introduced into the CFE system by sample pump at O.1 m//min with eluent fractions collected at 4 h intervals. Lecithine was obtanied 240 mg with purity of 98.3%(Fig.5-(6)). For a mixture of two substances having partition constants KA and KB, the symmetric separation is attained if the ratio of the flow rate of the two-phases solvent is maintained at F, /Fh= A/1/KAKB. CFE employs rotation of columns to promote the partitioning of components and the two phases completely fill the column. This design prevents both the formation of emulsions and oxidation of sample components.

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Fries rearrangement of phenyl 1, ο-tolyl 2, m-tolyl 3 and ρ-tolyl diphenylacetates 4carried out in nitrobenzene with anhydrous aluminium chloride (AlCl₃) at 60°C, gave diff erent yields and ortho/para ratios of the corresponding products hydroxyphenyl ketones, d epending upon the position of a methyl substituent on the phenyl ring. The rate of the reactions is in the order of 1>2>4>3, and the highest ortho/para ratio was observed for 3(Table 1, Fig.1 and Fig.2). The reaction of these aryl diphenylacetates was compared with the rearrangement of phenyl 5, ο-tolyl 6, m-tolyl 7 and ρ-tolyl 8; The yield and ortho/para ratio were higher than those of phenyl diphenylmethyl ketones with an exception of a large ortho/para ratio for 7 (Table 2). In the rearrangement of 1, 5 and phenyl triphenylacetate 9, the reaction rate and orthof para ratio were in the order of 5>1>9. Each acyl cation derived from 1, 5 and 9 (PhCH₂C=O, Ph₂CHC=O and Ph₃C=O) is understood to be effective electrophiles (Table 4). In the crossover reaction of 1, 5 and 9with toluene, the corresponding ρ-tolyl ketones were formed in moderate yields together with small amounts of ρ-hydroxyphenyl ketones (Table 3), including that 1 and 5 proceeded in both inter- and intramolecular pathways, while 9 is an intramolecular migration pathway. In order to examine possible reverse Fries rearrangement, the rearrangement products 10, 11, 12, 13, 14 and 15 were treated with AlC13 in nitrobenzene (Table 5). The formation of 1 and 2 indicated the reverse Fries rearrangement of 10 and 12, respectively, and a rearrangement from 11 to 1 and an isomerization from 11 to 10 were detected as seemingly slow processes. Compound 13 was recovered almost quantitatively. Compounds 14 and 15were found interconversible under these conditions.

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Rates of reactions of an excess amount of sodium nitrophenox Ides with several dinitrodiphenyl ethers or bromonitrobenzenes in 1, 3-dimethy1-2-imidazolidinone (dipolar aprotic solvent) have been measured. Rate parameters and activation parameters calculated from the Arrhenius standard expressions were summarized in Table 1 and Table 2. It was found from the rate parameters that the ratio of 2, 2'-, 2, 4'- and 4, 4'-isomer of dinitrodiphenyl ether was 3.8 : 34.9 : 61.3 respectively under the conditions of the equilibrium state at 120°C with an equally excess amount of sodium o- and p-nitrophenoxides. The correlation between entropies of activation at 120°C, ΔS^≠, and enthalpies of activation, 41--P, was shown in Fig.1. These plots could be classified into four groups an d each of them showed a good linear free energy relationhip. Group 1, 2 and 3 in Fig.1 had a sam e isokinetic temperature of 71°C and the rate of reaction at this temperature was 3.9 x 10^-5, 8.9 x 10^-8 and 3.6 x 10^-8s^-1respectively, so the rate ratio of nucleophilic activity of m-, p- and o-nitrophenoxide ion could be determined as 440 : 1: 0.4 respectively. Group 4 in F ig.1 had an isokinetic temperature of 216°C and the rate of reaction at this temperature was 2.0 x 10^-3 s^-1. The activation parameters for reaction 5 which rate was too slow to measure could be calculated as ΔH^≠ =10.6 kcal/mol, ΔS^≠ at 120°C= 62.1 cal/mol, that was well located on the line of group 3.

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In order to obtain fundamental data on the oxidation of saturated aliphatic aldehydes in the liquid-phase, the effect of solvents was studied. The oxidation reactions were performed at 0°C, 30°C and 40°C under atmospheric pressure of oxygen in varuous solvents in the presence or absence of radical initiator and cobalt catalyst. The rates of oxidation differed by a factor of 2.7 with the structure of aldehydes and the rates in ethyl acetate were always a little higher than those in chlorobenzene. Regardless of the kind of solvents or presence of catalyst, the initial rate of oxygen absorption was first order with respect to hexanal concentration. Except for some solvents, the rates of oxidation was correlated with (D-1) /(2D+1), where D is the dielectric constant of the solvent. The ester solvents, especially ethyl acetate, gave faster rates and higher yields of peroxy acids than non-ester solvents. The oxidation did not proceed in methanol even in the presence of metal catalyst. The rate of oxidation increased with the yield of peroxy acid. This indicates that the decomposition of peroxy acid affected the rate of the oxidation.

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Rates of acetylation of hydroxyl groups in Grayanotoxin(G)III w ere measured to investigate their reactivities. Products after acetylation were separated on thin-layer chromatograpy (TLC). The rates of reaction were calculated from the amounts of the products measured TLC. The observed rate constants (k₁) were 6.2 x 10^-1 (min^-1) at 100°C and 9.7 x10^-3(min^-1) at 0°C. Reactivity on acetylation of hydroxyl groups in G-III decrease in the order of 6-OH>3-OH≥14-OH>16-0H. At 0°C, only 6-acetyl was selectively synsesized from G-III.

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The morphological change and fusion behavior of linear high-density polyethylenedecalin gel prepared by cooling its hot solution at various rates were investigated detailedly as a function of cooling rate of the hot solution. A heating DTA curve of gel prepared by cooling slowly at a rate of 1 IC/min showed a single endothermic peak, while two peaks were observed with increasing the cooling rate. On the other hand, X-ray diffraction measurements of gels showed that the diffraction intensity as well as degree of crystallinity lowered with increasing the cooling rate, suggesting that quasi-stable crystallites were formed in a rapidly cooled gel and quantity of them increased with increasing the cooling rate. In order to elucidate the fusion behavior of the rapidly cooled gel including qua si-stable crystallites, an observed DTA curve having two endothermic peaks was decomposed into following elements (heating DTA curves) assuming the quasi-stable crystallite to be composed of structurally stable component having regular arrangement of polymer chains and quasistable one having irregular arrangement: the stable component melts with a single endothermic peak, while the quasi-stable component at first reorganizes to the stable one with an exothermic peak and then melts with an endothermic peak. These peaks (curves) were constructed using the quasi-Voigt function and simulation was carried out. As a result, the observed DTA curve could be well decomposed into the above-mentioned elements. According to the decomposed DTA curve, quantity of the quasi-stable component, which was estimated from its peak area, increased with increasing the cooling rate. This tendency is reasonable as compared with the result of X-ray diffraction.

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Metal ions adsorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety of 1.79 m molig-Res. (MC-90), were examined. MC-90, showed a good adsorption ability for various metal ions such as U(VI), Cu(II), Hg(II) and Ca in aq.28% concentration of sodium chloride soln. in comparison with iminodiacetic acid type chelating resin. One gram of MC-90 adsorbed 1.70 mmol of Cd, Ca or mixed metal ions consisting Cu(II), Ni(II) and Cd. Selection factor (K_Ca^M for each metal ion (M) of pH 3.0 aq. soln. on calcium salt of polyamine-substituted methylphosphonic acid moiety in MC-90 was U(VI) 31.0, Cu (II) 12.3, Hg(II) 1.3, Ca 1.0, Zn 0.5, Fe(III) O.4, Ni(II) O.3, Cd O.2, Cr (III) 0.1and Na O. O. The qua ntity of U(VI) adsorbed on MC-90 at the concentration of 20 mg⋅dm^-3 U(VI), was 0.03 mmol/g-Res. in 30% H₃PO₄ aq. soln. and 0.20 mmol/g-Res. in 10% H₂SO₄ aq. soln. The adsorbed U(VI) on MC-90 was eluted with an aqueous solution of 1.0 mol⋅dm^-2Na₂S-5.0 mmol⋅dm^-3 NaOH.

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Ion flotation of sixteen metal ions (Mn(II), Co(II), Cd(II), Zn(II), Cu(II), Pb(II), Bi(II), Fe(III), In(III), Ga(III), Cr(III), Y(III), V(V), Mo(VI), Cr(VI)) was investigated in (1-hydroxyethylidene)bisphosphonic acid (HEBP) solutions with dodecylammonium acetate (DAA) as a surfactant. A 20 cm³ aliquot of 4.38 x 10^-4 mol⋅dm^-3 HEBP solution containing (3.94-4.32) x 10^-4 mol⋅dm^-3 of the above-mentioned metal ions and 8.77 x 10^-4 mol⋅dm^-3 of DAA was adjusted to the desired pH and subjected to flotation in a cel l (20 cm × 2.5 cm i. d. ) for 10-20 min with nitrogen bubbles. The effect of pH on the recovery of metal ions was examined and recoveries of 98-100% (except for Cr(VI)) were obtained at the appropriate pH ranges. The compositions of the floated complexes were determined to be a metal/HEBP ratio of 1: 1 for the divalent metal ions. The stability constants of the complexes were also determined from the pHpercent flotation curves by nonlinear leastsquares method.

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Hydroxybenzoic acids have been usually synthesized from alkali p henolates and carbon di oxide by the Kolbe-Schmitt reaction. We have found the reactions of alkaline earth metal phenolates with carbon dioxide to give salts of hydroxybenzoic acid s in appreciable yields. Barium phenolate was carboxylated in N, N-dimethylformamide at 140°C and 180°C under 1.1 × 10⁶Pa of carbon dioxide to give salts of salicylic acid and ρ-hydroxybenzoic acid in about 50 percent total acids yield.

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A sawdust of Sugi (Cryptomeria japonica D. Don ) wood was treated under conditions of high steam pressures (2.75-2.94 MPa) at 230°C for 5-12 min and an explosive operation. The explosion products from the heart- and sap-wood were washed with water and extracted with hot benzene in order to remove a lignin-like component. The explosion treatment increased the benzene-soluble fraction as well as the methanol extracts. From the benzenesoluble fraction, vanillin 1, coniferyl aldehyde 2, and unidentified phenolic compounds were isolated along with sandaracopimaric acid 3, sandaracopimarinal 4, sandaracopimarinol 5, ferruginol 6, and β-sitosterol.

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