The frequency shift of the lowest electronic transition for the dinegative ion of Eosin Y produced by the weak electric field was studied by means of the Heckel MO perturbation theory. In the calculation the charge density approximation was employed and the formula for the frequency shift was derived as Eq. (1),
here Z_s is the effective charge numbers of the cation. ρ_λ⁰ and ρ_{λHOMO, LUMO} are the ground and excited pi electron densities at λ-th atom respectively. ρ_{λHOMO→LUMO} and ρ_λLUMO→b are the transition charges corresponding to the electronic transitions (HOMO→ LUMO) and (LUMO→b)respectively, while R_s and R_λ are the position vectors of the charges Z_se and the λ-th atom in the dye ion. On the basis of Eq. (1), the positional effect of the charges on the frequency shifts was studied with a fixed Z(=0.01). The results obtained indicate that th e blue shift was produced markedly by the charges placed on the side of the xanthene ring. On the contrary only a slight blue shift was produced when the charges were placed around the benzene ring.

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Pensities, osmotic and activity coefficients of aqueous guanidinium salts (acetate, chloride, bromide, thiocyanate and nitrate) solutions were measured by pycnometry and i sopiestic comparison method at various concentrations at 15° and 35°C. These data were combined with the previous data at 25°C to obtain the thermodynamic excess quantities, excess entropy (S^ex)enthalpy (H^ex) and Volume, (V^ex) for aqueous guanidinium salts solutions. As shown in Fig.3, 4, 5 and Table 5, excess partial molal quantities, G₂^ex, S₂^ex, and H₂^ex for the investigated guanidinium salts at high concentrations were all negative and decreased in the order acetate > chloride > bromide > thiocyanate > nitrate, which paralells the order of structure making abilities of counter anions among these salts. The values of excess partial molal volumes V₂^ex of these salts ware positive and lied in the order nitrate > bromide > ohloride, as seen in Table 5. As shown in Fig.6, the values of excess partial molal entropies, for water S₁^ex were positive in all salt solutions and increased with the increase of the structure breaking abilities of the counter anions. The values of (∂C_pgu+⁰ /∂P)_T obtained from temperature dependence of partial molal volume of guanidinium ion at infinite dilution were positive for chloride, bromide and nitrate. These results were -well interpreted in terms of the overlapping effect of hydrated cosphere between hydrated cation and anion by regarding the guanidinium ion as a stucture breaker.

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In order to substantiate the author's theoretical proposal for the mechanism of transference of solute molecules through liquid-liquid interfaces and for the magnitude of interfacial resistance, transfer processes of propylamine and butylamine through the water-benzene interface have been examined and analyzed by a theoretical equation which deals with the variation in the amount of adsorption.
Although the observed diffusion coefficients were considerably concentration-dependent, a procedure for the transformation of processes into equivalent one was proposed in which the diffusion coefficients were concentration-independent.
The values thus obtained on the activation free energy of desorption from the interface agree to the second digit with those estimated from the result obtained in a study using fatty acids of straight chain as the transfer material (17 kcal/mol (30°C), 18 kcal/mol (50°C)).
An unusually rapid process in the early stages has been found as a result o f the analysis (Table 2). This may be ascribed largely to the Marangoni effect by its temperature dependency.

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The secondary condensation product (dibenzylideneacetone) of benzaldehyde with acetone has been obtained readily in high yield but it is difficult to prepare that of variillin with acetone by the use of base catalyst. The kinetics of the aldol condensations of benzaldehyde and vanillin with acetone was investigated in the presence of base catalyst with a view of exarnining, the difference in the reactivities between the two aldehydes.
The rate of the secondary condensation of benza l dehyde w ith acetone as well as the primary condensation showed a first order dependence on hydroxide ion concentration and the initial concentrations of each reactant. The accumulation of a reaction intermediate, ketol, was not observed during the reaction. From these results, it was concluded that the addition of the carbanion generated by removal of a proton from methyl ketone to benzaldehyde was the rate determining step in the overall condensation reaction. The activation energies of the primary and secondary condensations were 9.5 and 4.1 kcal/mol, respectively. There was also significant difference in the frequency factors.
In the case of the conden s ations of vanillin with acetone, the rate equations for the primary and secondary condensations were found to be rate = k [Acetone]₀[Vanillin]₀([OH^-]₀[Vanillin]₀)and rate= k[VA]₀[Vanillin]₀([0H^-]₀[VA]₀[Vanillin]₀), respectively, and the additi on step was rate-determining as in the case, of benzaldehyde., The activation energies in the primary and secondary condensations were 11.3 and, 12.3 kcal/mol, respectively and the difference in the frequency factors was small. The activation energy seems to depend upon the stability of carbanion arising from ketone.

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The mechanism of nitrous acid decomposition was studied. It was concluded that the reaction 2HNO₂→ NO + NO₂ + H₂O took place at the gas-liquid interface. The rate of the reaction was found to be determined by the diffusion of nitrous acid from the bulk of solution to the gas-liquid interface when the solution was allowed to stand in a stream of nitrogen. Under the shaking condition, on the other hand, the diffusion process was accelerated so that the rate-determining step was shifted to the reaction at the interface. These conclusions were consistent with the results as to the dependence of the rate upon the concentration of HNO₂, H+ and neutral salt as well as the values of the activation energy and of the rate constant.

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The adsorption and desorption of hydrogen at 400°C and the catalytic actiyity of dehydro genation of isopentane were studied on active charcoal or Co- or Cu- impregnated active charcoal. It was found that the catalytic activity is closely correlated to the rate of the adsorption and desorption of hydrogen. “hydrogen spillover” was a scertained by investigating the hydrogen adsorption. The equilibrium amount of adsorbed hydrogen was independent of metal species and contents while the rate of adsorption depended on them. The pressure and temperature dependences of the amount of adsorbed hydrogen suggest that hydrogen atoms formed on the carbon are in equilibrium with hydrogen molecules in the gas phase through metal particles on the carbon. The desorption of hydrogen was examined with transient response methods applied t o dehydrogenation of isopentane. It was confirmed that “hydrogen reverse-spillover” proceeds on the present catalyst systems.

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The preparation methods of Ru-AC (active carbon)-K and Os-AC-K catalysts for ammonia synthesis were examined. The catalytic activity of Ru-AC-K increased linearly with the potassium content above 1 mmol/g-cat. below which no activity was found (Figs 1 and 7). About 6 times as much as the stoichiometric amount of hydrogen was consumed during reduction of RuCl₃ on AC (Fig.2), whereas the catalytic activity was indepenent of the extent of hydrogen consumption. Although hydrogen chloride was formed during the reduction, about 20% of chloride ion remained on the catalyst.
The activity of Ru-AC-K was rough ly proportional to the amount of CO chemisorption on Ru-AC (Figs 3 and.6), which increased linearly with Ru content, attaining a plateau value above 3 wt% (Fig.5), and was unaffected by pretreatments of AC with HNO₃ and/or. NH₄OH (Table 1, Figs 5, 6 and 7). RuCl₃ was almost completely adsorbed on the active carbon during the preparation of low Ru-content catalysts (Fig.4). The specific activity of supported metals was independent of the oxidation state of starting material of Ru (II, IVN) or Os (III, IV, VI, VIII).

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Dye sensitized anodic photocurrent at the ZnO sintered electrode/electrolyte interface was studied. The sensitized photocurrent is concluded to be caused by electron transfer from the excited dye molecule adsorbed on the electrode to the electrode. The quantum yield of the dye sensitized photocurrent is determined to be about 25% from the analysis of the photocurrent decay curve on the assumption that the dye which injected an electron to the electrode was not restored.
The photocurrent increase in the presence of the reducing agents such as hydroquinone and N, N, N', N'-tetramethyl-p-phenylenediamine (TMPD), was studied in detail. The dye sensitized photocurrent decays with time under continued illumination, but it keeps on in the presence of reducing agents (Fig.3). The saturation in the photocurrent with increased light intensity is also largely diminished by the reducing agents (Figs 5, 6). From these results, it is concluded that TMPD supplies electron to the dye which injected electron to the ZnO electrode, and prevents it from being deteriorated. Hydroquinone acts not only as an electron supplier to the dye but increases the photocurrent. This might be explained by a “ current doubling” effect brought about by the two-step oxidation process of hydroquinone to quinone.
When p-phenylenediamine and its derivatives are added to the electrolyte-dye solution, a tunnelling current is observed at high electrode potential and weak illumination.

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The reactions of surface OH group of TiO₂ with alcohols were studied using the boiling and reflux reaction method. The intermediate product of TiO₂ prepared by sulfuric acid process was washed thorouhly, calcined at 120-800°C and used as the test samples, which has various amount of surface OH groups and acid sites, for comparison of ractivity toward BuOH. The reactivity of TiO₂ relates more closely to the value of amount of the total surface OH groups minus the amount of stronger acid sites, than to total amount of surface OH groups. The commercial product calcined at higher temperature has a few OH groups, and is less reactive. Regeneration of OH group by treatment of the anhydrous TiO₂ with H₂SO₄ gives much promoting effect on the reactivity of TiO₂. The order of the reactivities toward BuOH isomers is as follows: n- > i- > s-, t-BuOH If the esterification of the surface acidic OH group would proceed with the following mechanisms TiO-|-H + HO-|-R→ TiO-R+ H₂O the order of the reactivities of alcohols, predicted in terms of the Taft's substituent constant, is conflict with the order shown above. From the facts that the surface OH groups which are not so strongly acidic can participate in the reaction 'and that if the density of OH group becomes lower the reaction is difficult to occur, the estrification reaction would be concluded to proceed with repeating the dehydration (ring closure) and the addition of alcohol (ring opening) according to the following fashion:

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In order to clarify the moisture absorption process of powdered sodium bromide anhydrate, water vapor absorption isotherm, changes in X-ray diffraction intensity, surface area and surface conductivity were studied. Their data are expected to represent sensitively the surface property changes of the salt concerned during its hygroscopic process.
The relative humidities (rH), at which dependences of surf ace properties on water vapor pressure in an atmosphere begin to change, were determined through the analysis of data obtained by the above-mentioned tests. Small discrepancy was found among the rH values deduced by the methods. This means that differences in sensitivities and characteristics of the methods dominate the values. Therefore, a comprehensive comparison of the results is necessary.
The thicknesses of adsorbed water layers required to cause changes of the surface properties of NaBr particles were given by comparing their measured values with the water vapor adsorption isotherm. The authors pointed out that the moisture absorption of sodium bromide proceeds stepwise with increasing the number of adsorbed water layer by way of the following stages at 30°C: monolayer adsorption (7-10% rH) → two layer adsorption and formation of hydrated ion (24% rH) → four or six layer adsorption and dihydrate (NaBr·2H₂O) formation (38% rH) → formation of solution films with a measurable thickness (46-48% rH) → formation of saturated solution films (56% rH) → deliquescence.

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Influences of silicon dioxide (SiO₂) as an additive and atmosphere on mechanochemical degradation of poly (vinyl chloride) (PVC) powder occurred during mechanical grinding of the mixture of SiO₂-PVC have been investigated.
When PVC powder (the degree of polymerization:1510) was ground independently in air or in nitrogen atmosphere, decrease of the degree of polymerization and the formation of carbon carbon double bond with increasing dehydrochlorination were observed. However, the mechanochemical degradation through the mechanical scission of principal chain (C-C bond) and side chain (C-Cl bond) in PVC molecules were hardly detected and also influence of atmosphe re made little difference.
Whereas, w hen PVC and SiO₂ were mixed and ground together in air or in nitrogen, the mechanochemical degradation of PVC was much accelerated, especially in nitrogen. For examp le, compared with ground mixtures for 24 hr in nitrogen, the degree of polymerization of PVC was remarkably down to 500 in the case of mixing weight ratio 1/1 as PVC/quartz, to 200 in 1/4 and to 100 in 1/1 as PVC/silica gel. Moreover, the amount of dehydrochlorination and th e number of the double bond happened by mechanical scission of C-Cl bond increased to 16% and 15/1000 monomer, respectivity. From the change of solid acidity of silica gel in the grou nd mixture, it was apparent that the mechanochemical degradation of PVC was caused not only by the physical effect of grinding accelerator as found by the addition of quartz, but by the catalytic action of the fresh surface of SiO₂ during grinding had an important role.
The possibility of mechanochemical reaction between activated surfaces of SiO₂and PVC during grinding was suggested by infrared spectra.

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Ultra-pure solid potassium hydroxide was prepared by the evaporation of KOH solution in cathodically protected silver vessel. Relation among amount of silver dissolved, KOH concentration and cell voltage (potential between Ag vessel cathode and Pt anode) was investigated passing a protecting current in a siver vessel.
The purity of KOH obtained was 96.9 % and the amount of silver dissolved from cathode was 0.00022% at the cathodic current density of 6 mA/cm². The dissolution of silver was observed to increase with the decrease of cell voltage.

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Zirconyl chloride solutions (O.01 to 1.8 mol/l) and the same with various amounts of HCl and urea were heated for 5 to 170 hr at their boiling temperatures. The hydrolysis products under different conditions were examined by means of X-ray diffractometry, IR spectrometry, electron microscopy and thermal analysis.
The particle shape and size o f the products depend on ZrOCl₂ concentration: fine crystals (about 200 Å) are formed in 0.01 mol/l whereas cube-like and sphere-like particles (about 1000 Å ) resulting from coagulation of fine crystals (about 100 Å ) are formed in O.1 mol/l and 0.3mol/l, respectively (Fig.2).
Two kinds of products were obtained depending on the concentration of HCl: hydrous zirconia is formed in the solution whose concentration of HCl being lower than about 1 mol/l and the compound containing about 5 wt% Cl is formed in much more concentrated solution.
The hydrous zirconia has a monoclinic crystal structure. A small amount of hydrous zirconia having a tetragonal or cubic crystal structure is formed together with the monoclinic hydrous zirconia when the concentration of HCl is lower than 0.2 mol/l.
The hydrous zirconia particles are dehydrated without any chan g es in particle shape, size and crystal structure when they are heated at 400°C in air. The compound containing Cl decomposes to ZrO₂ with monoclinic crystal structure at 400°C in air.

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The atomic absorption behavior of NH₄F, NH₄Cl, NH₄Br and NH₄I in the range of 1O^-4- 5 x 10^-1mol/l on the determination of sixteen elements was studied using air-acetylene flame.
The interferences of ammonium halides on various elements were observed even in the low concentration range of 10^-4-10^-3 mol/l and they generally increased with the increase of flowrate of fuel gas. The presence of the four ammonium halides decreased the absorption intensity of Pt, Au, Cu, Mn and the existences of NH₄F and NH₄I decreased the absorption intensity of Cd, Pb, Zn and Co, Ni, Ca, Mo, V, respectively. The addition of NH₄Cl and NH₄Br increased the absorption intensity of Fe, Co, Ni, Eu, Mg, Ca, Cr, Mo, V, and the presence of NH₄F and NH₄I increased the absorption intensity of Cr, Mo, V, and Fe, Eu, Mg, Cr, respectively.
No interferences of ammonium halides were observed for other cases. It was found that these interferences could not be due to physical factor, but to some chemical reaction occurring at the lower temperature parts in the flame.

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A potentiostatic determination method was applied to a potentiometric titration whose experimental curve does not show a sharp inflection point or a symmetric shape.
Titration curves for a standard solution (known concentration), and a sample solution, of definite volume V, were determined at a constant ionic strength by using an ion-selective electrode. Volumes of titrants required to reach any constant potential, v_s and v, were read off respectively on titration curves of the standard solution and the sample solution. If x=(V+v)1(V+v_s), the concentration of the sample, C_x, is given by C_x=ax+b, where a and b are constants and dependent upon concentrations of the standard solution as well as the titrant and are independent of the potential. This method is applicable only to the precipitation titration and has an advantage, namely the same calibration curve can be utilized irrespective of the solubility product of the precipitate and of the constant potential used, provided that concentrations of the standard solution and the titrant are constant and stoichiometric coefficients of the precipitation reaction are identical.
If the volume of the titrant req uired to reach the constant potential was read off in coin pleximetric or acid-base titration, the concentration is given by C_x=a'v+b', where a' is a constant and dependent upon the concentration of the titrant as well as the constant potential chosen and b' is a constant and dependent upon the constant potential chosen.
The above methods could be applied satisfactorily to F^--Ca²⁺, Ag⁺- CrO₄^2-, Ag⁺-edta, and β-alanine-NaOH systems.

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X-ray K-absorption spectra of arsenic, selenium and bromine in the states of simple substances and various compounds have been s measured in order to apply the X-ray K-absorption spectroscopy to the chemical state analyses of these elements. An X-ray diffractometer with a molybdenum-target tube was used in the ordinary arrangement for diffraction experiment, except setting a topaz analyzing crystal at the center of its goniometer. Sample mounting to the apparatus was done with the following techniques. A powder sample was mixed in white vaseline by use of a thin spatula, and was uniformly spreaded on a 6 μ-Mylar film. Aqueous and ethanol solution samples were placed in a Mylar-window cell (Fig.1). Bromine and bromoform samples were placed in a Teflon-window cell (Fig.2). The sample was placed between a divergence slit and the analyzing crystal, and was measured under the experimental condition of Table 1.
The abs orption spectra of these elements in oxides and sulfides had pronounced fine structures at the short-wavelength side of the absorption edges. On the contrary, the spectra of the elements in zero or negative valence state had small undulations. The wavelengths of the absorption edge and peaks shifted to shorter side as the valence of the absorbing element became higher. The energy differences between the absorption peaks of arsenic sulfides were smaller than those of arsenic oxides. A K-photoelectric absorption-coefficient ratio of the first absorption peak to the third peak of a powder sample was smaller than that of aqueous or ethanol solution sample. Details of an observed absorption spectrum, especially height and wavelength of the first absorption peak, depended upon the thickness of sample. Therefore, reasonably thin sample was required in order to obtain an accurate spectrum.

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N-(1-Acetonylethylidene) (m- and p-substituted) anilines (substituent: Cl, COOH, OH, OCH₃CH₃, and H) have been synthesized by the condensation of acetylacetone with the correspo nding anilines. The predominant tautomeric structures of these Schiff bases were estimated, and the effect of the substituents was investigated by means of IR, NMR and ultraviolet spectra. The presence of the v_N-H vibration near 3000 cm^-1 predominance of the ketoamine form over the enolimine. The result is also supported by a simple Hiickel molecular orbital calculation. The ethylidene CH₃, proton shift observed at the higher magnetic field is subject to solvent effect. The chemical shift of the NH proton observed at the lower magnetic field can be correlated with Hammett parameters. Two absorption bands at about 205 and 230 nm are assigned to the π → π* transition of the aromatic ring. The band at about 325 nm is due to the π → π* transition of the hydrogen bonded chelate ring. and a considerable hypsochromic shift is observed as the substituent becomes more electronegative.

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The structure of the complexes (I) and (II) produced by the reaction of nitrOanilines with amide ion has been studied by measuring the visible, IR and NMR spectra.
These complexes were formed as red crystals by adding a dichlo romethane solution of a nitroaniline to potassium amide in liquid ammonia, but they are rather unstable in air.
A comparison of the IR spectra due to the _??_ bonds of the complexes (I) and (II)with those of the_??_ bonds of the complexes (III) and (IV) shows that the stretching vibration absorption bands for these two groups are observed as the strong broad bands in the region 1018-1040 cm^-1, and they are alike in shape and wave number.
The followings can also be pointed out from the IR spectra.
(1) The infrared absorption wave number of aromat ic primary amines changes to that of aliphatic primary amines.
(2) The v_N-C-N absorption appears as the strong broad bands.
(3) The δ_N-N absorption bands of the _??_ bonds in the complex (I) appear at 1628 and 1603cm^-1 and the coresponding bands in the complex (II) are at 1627 and 1602cm^-1. The wave numbers of the complex (I) are very close to those of (II)
The ring protons of the complexes (I), (II), (III) and (IV) resonate at higher magnetic fields than those of the parent nitrobenzenes. On the basis of these results, it is concluded that the complexes (I) and (II) are Meisen _heimer type complexes.

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Methyl phenylcarbamate (MPC) was irradiated by ultraviolet light in dilute ethanol solution under bubbling of oxygen at room temperature. The reaction process was investigated by measuring absorption and fluorescence spectra.
It has been shown that the intramolec ular photorearrangement of MPC is the initial stage of photoreaction. MPC is converted into methyl 2-aminobenzoate and methyl 4-aminobenzoate. At the initial step of the photoirradiation, the production of aniline was not detected. In the second step of this photorearrangement reaction, the formation of methyl 3-aminobenzoate was obsereved. This photorearrangement reaction can be considered not by such a radical reaction as the photo-Fries rearrangement but by a kind of electrophilic reaction.

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The photoreduction of p-benzoquinone in water in the presence of various metal ions was investigated.
It was found that the rate of the photoreduction of p-benzoquinone in the presence of Ni²⁺ ion was faster than that in the absence of metal ion. The reason seems that the presence of Ni²⁺ ion affected the π-π* excited state of p-benzoquinone in water (Table 1).
On the other hand, the rate of the photoreduction of, p-benzoquinone in the presence of excess of Cu²⁺ ion was slower than that in the absence of metal ion. It would be explained by the following reaction in the dark reaction, the equilibrium reaction between hydroquinone and p-benzoquinone as shown below occured by copper ion.

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The dehydrochlorinations of 1, 1-dichlorobutane and 2, 2-dichlorobutane through molten salt media have been studied. The molten salts employed here were binary eutectics (ZnCl₂-KCl and SnCl₂-KCl) and ternary eutectics ZnCl₂( 3 ) - KGl( 1 ) - NaCl( 1 ) and CuCl ( 3 ) -KCl ( 1 ) - NaCl( 1 ).
cis- and trans-1-Chloro-1-butene (cis/ trans=1.4-2.7) were obtained along with 4-chloro-1-butene (a rearranged product) by the reaction of 1, 1-dichlorobutane through the molten salts and, through ZnCl₂ melts, additional formation of considerable amounts of butadiene was observed. The formation of butadiene is considered mainly due to the 1, 4-elimination reaction of 1-chloro-2-butene, a rearranged product. The preferred formation of cis isomer over trans isomer was explained by considering the interaction between the carbonium ion intermediate from 1, 1-dichlorobutane and the molten salts surface.2, 2-Dichlorobutane gave the cis and trans-2-chloro-2-butene (cis/trans = 0.3-0.46) together with 2-chloro-1-butene.
In order to study the influence of the composition of the molten salts on th e reactivity of gem-dichlorobutanes, their dehydrochlorinations were carried out with binary melts (ZnCl₂-KCl and SnCl₂-KCl) of various composition.

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The ring opening reactions of 2, 2-dichlorospiro[cyclopropane-1, 9'-fluorenes] [2] with silver ion in alcohols gave the solvolysis products, 1-alkoxy-1, 1 (2, 2'-biphenylene) -2-chloro-2-propenes [3] and/or 3-alkoxy-1, 1 (2, 2-biphnylene)-2-chloro-1-propenes [4], in satisfactory yields. A time-course study of the product ratios revealed that [3] were kinetic-controlled products and [4] were equilibrium-controlled products. Furthermore, stereochemistry in [3] was discussed on the basis of Woodward-Hoffmann's theory.

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The reactivities of the formyl and methyl groups in pyruvaldehyde [1] were studied; the former by means of NaHSO₃ addition reaction and Ktioevenagel reaction, the latter by means of H-D exchange reaction, measurement of ¹⁸C-chemical shift and Claisen-Schmidt reaction, respectively. The results were compared with those of the other aliphatic aldehydes and ketones.
The reactivity of the formyl group in [1] was higher than that of the usual a liphatic aldehydes and the reactivity of the methyl group in [1] was as same as that of the methyl group in acetaldehyde.
The product of the aldol condensation of [1] was scarcely obtained in spite of higher reactivity of [1]. This seemed to be caused by the fact that the reactivity of the formyl group in [1] was so high that the polymerization of [1] preceded the aldol condensation.

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4-Anilino-2-benzamido-6-phenyl-1, 3, 5-triazine [2 a] and N², N⁴, N⁵-tribenzoyl-N¹-phenyl- biguanide [3 a] were obtained by the reaction of N¹-phenylbiguanide with excess of benzoyl chloride in acetone. Similarly 2-benzamido-4 (substituted anilino) -6-phenyl-1, 3, 5-triazine [2 b- 2 d and 2 f] and N², N⁴, N⁵-tribenzoyl-N¹- (substituted phenyl) biguanide [ 3b-3d and 3f]were obtained by the reaction of n¹- (p-tolyl) biguanide, N¹-(p-methoxyphenyl) biguanide, N¹- (p-chlorophenyl) biguanide and N¹- (m-nitrophenyl) biguanide with benzoyl chloride, respectively. The properties of the products are shown in Table 2 and Table 3. [2 a] and 2-amino- 4-anilino-6-phenyl-1, 3, 5-triazine [1 a] were obtained by the hydrolysis of [3 a]. N², N⁴, N⁵-Tetrabenzoyl-N¹-phenylbiguanide was obtained by the reaction of [3 a] with benzoic anhydride.

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The reactions of coumarin diethyl acetal (2, 2-diethoxy-2 H-benzo[ b ]pyran) [1] with nucleophiles were investigated. [1] Reacts easily with aniline and carbonyl reagents to give corresponding condensation products in high yields. The reactions of [1] with bifunctional nucleophiles proceed on two different types, A and B. In the reaction of type A, 2 moles of ethanol are eliminated from [1] and nucleophiles to give spiropyrans or 2-imino-2 H- benzo[ b ]pyran derivatives, the latter being obtained exclusively when a nucleophile contains unsubstituted amino group. On the other hand, in the reaction of type B, coumarin and ethyl derivatives of nucleophiles are obtained and only 1 mole of ethanol is eliminated. When a nucleophile contains acidic group such as mercapto or carboxyl group, the reaction of type B is predominant. The reaction of type A exclusively occurs when a nucleophile contains less acidic group such as hydroxyl or amino group.

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In the monosulfonation of m-cresol [1] and m-methylanisole [6] with 90% sulfuric acid the effects of reaction temperature and mercury catalysis on the isomer distribution of the 4 and 6-sulfonated products (6-S/4-S) have been studied. The isomer ratios were determined by bicomponent NMR analyses of their signals of methyl protons. All sulfonic acids were finally purified through their anilinium salts by the method described previously. They were chara cterized by the IR, UV and NMR spectra, and were identified into their sulfonamides and s (p-nitrobenzyl) thiouronium salts. The ratios of [1] 6-S/[1] 4-S in the products of the sulfonation of [1] with 90% sulfuric acid for 1/2 hr at 20, 60, 100 and 120°C were 64/36, 52/48, 42/58 and 32/68 respectively. When mercury (II) chloride was used as a catalyst, the ratios of the 6-isomer increased (at 20, 60 and 100°C, they were 81/19, 66/34 and 51/49 respectively). In the sulfonation of [6] at 20-120°C, the ratios of [6] 6-S/[6] 4-S gradually increased from 17/83 to 26/74, and slight effect of mercury (II) chloride was observed.

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Polyimides (PI) containing pyrazine ring were synthesized and their thermal stabilities, and solubilities were investigated.
Two isomers (2, 5 and 2, 6-) of bis (p-aminophenyl) pyrazine were prepared by the reaction of p-(bromoacetyl) acetanilide with ammonia. Upon hydrolyses, corresponding amino com pounds (BAPP) were obtained.
Polyamic acid s (PAA) were synthesized by the polymerization of these amines with aromatic tetracarboxylic dianhydrides.
Inherent viscosities of thes e PAA are 0.22-1.86 (O.5 % DMAc solution, 30°C). These PAA were converted into PI by heating at 250°C.
The obtained PI degrade at about 480-590°C in nitrogen atmosphere. PI derived from 2, 5-BAPP are more stable than PI from 2, 6-BAPP, and comparable to PI from 4, 4''-diamino-p- terphenyl (DATP) which is an analogous diamine without hetero rings. However, the thermal stability of PI containing pyrazine ring is inferior to one derived from DATP in air.
All polyimides are insoluble in DMAc, m-cresol, etc. PI containing pyrazine ring are soluble in conc. H₂SO₄ and methanesulfonic acid. PI from 2, 6-BAPP are more soluble than PI from 2, 5 -BAPP or 3, 6 -dimethy1-2, 5-BAPP.

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The reaction of fibrous cotton cellulose with o- or p-chlorophenylcarbanilates (o- or p-CPCA)(isocyanate generators) has been studied in order to obtain the cellulose carbanilate c ontaining high nitrogen.
The reaction was carried out by heating a cotton linter with o- or p-CPCA dissolved in N, N-dimethylformamide (DMF) at 120°C for 10 hr under nitrogen atmosphere. The product containing the highest nitrogen (5.5%) was obtained from the reaction mixture of cotton linter, DMF and o-CPCA in wt. ratio 1.00: 40.6: 27.4 (6 times of the amount required for tricarbanilation) respectively. The product containing the highest nitrogen (5.3%) was obtained from the mixture of cotton linter, DMF and p-CPCA in wt. ratio 1.00: 60.9: 13.7 (3 times of the amount required for tricarbanilation) respectively. Under the same reaction condition, o-CPCA is more reactive than p-CPCA. This may be due to the fact that o-CPCA generates isocyanate more easily than p-CPCA.
The amount of residual cellulose I crystal in various cellulose carbanilates was measured by X-ray diffractin method.
The results showe d that the reaction of cotton. cellulose with CPCA is heterogeneous which Proceeds from amorphous to crystalline region in cellulose fiber.

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The permeability of gaseous molecule through pores in the Knudsen region was numerically calculated by considering the geometrical arrangements and distances of the spheres in the packing model of simple cubic lattice type or hexagonal closest packing type of particles. The results of the theoretical calculations agreed approximately with those obtained by the Kundsen diffusion equation (eq. (14)) where a radius equivalent to the neck in pore (c. f. Table 3) was selected as an effective pore radius. These results showed that the diffusion in pores is con trolled by the neck. From the calculation of the diffusivity of the gaseous molecule with diameter a, the effect of molecular diameter on the permeability through these packing models of particles was found to be greater than that predicted through the cylindrical pores (c. f. Fig.5).

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For the purpose of recovery and removal of zinc from the waste solution in viscose rayon industry, the adsorption and elution of zinc ion by using the macroreticular chelating resins (RST and RMT) containing polyethylenepolyamine groups were investigated by column operation. For comparison, two porous type resins, products of Mitsubishi Kasei Kogyo Co., Diaion CR 10 (chelating resin containing iminodiacetic acid groups) and Diaion PK 212 (strongly acidic cation exchanger), were also used. The approximate composition of the waste solution was as follows: pH 1.35, Zn²⁺ 726 mg/l, Ca²⁺, Mg²⁺ 55 mgil (as Ca²⁺), SO₄² 35.9 g/l, total salt 43.6 g/l, organic matter 8.9g/l.
The cation exchange resin PK 212 does not show the selective adsorptivity toward zinc ion in the waste solution. As the chelating resin CR 10 exhibits the satisfactory adsorptive activity toward zinc ion and also shows the adsorptivity toward calcium ion, the eluate contains calcium ion. And a considerable volume change of the resin was found during the cycle of adsorption, elution and regeneration. The chelating resin RST exhibits the fairly selective adsorptivity toward zinc ion and the break-through capacity of it was 13-16 grams of zinc per liter resin under following conditions: loading solution, Zn²⁺ 400-700 mg/l, pH 6.0-6.5, space velocity 15. The elution of zinc adsorbed was accomplished by passing 2-3 N sulfuric acid soluti on through the column. The eluate contained 10-15 grams of zinc sulfate per liter and could be reused as a spining solution. The recycle of adsorption, elution and regeneration was found to be satisfactory.

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Fluorescence spectra of 4-methyl-7-anilinocoumarin (MAC), 4-methyl-7-diethylaminocoumarin (MDC) and dansyl-_L-alanine (DNS-L-Ala) were measured in aqueous solutions of cationic surfactants.
MDC and DNS-L-Ala form complexes with dodecyl pyridinium chloride (DPC) and the intensities of fluorescence decrease with increasing concentration of DPC. On the other hand, aqueous solutions of DPC does not quench the fluorescence of MAC.
The CMC of octadecyltrimethylammonium chloride (OTAC) was determined by the measurement of the change of the fluorescence intensity of MAC or MDC in aqueous solutions of OTAC. This CMC was higher than that determined by the measurement of specific electric conductivity.
It was recognized that when MAC and MDC were solubilized into OTAC micelle, the polarities of these solutions are 27 and 47 in units of dielectric constant, respectively.

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Fluorescence spectra of 4-methyl-7-anilinocoumarin (MAC), 4-methyl-7-diethylaminocoumarin (MDC) and dansyl-L-alanine (DNS-_L-Ala) were measured in aqueous solutions of poly (oxy ethylene) nonylphenyl ethers (NP) of various poly (oxyethylene) chain lengths.
CMC could be determined by the measurement of the solubilization curves of fluorescent probes into surfactant micelles. The polarities of the solutions in which MAC and MDC were solubilized increase with increasing poly (oxyethylene) chain length. On the other hand, the polarity of the solution in which DNS-_L-Ala was solubilized decreases.

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The esterification rates of dl-menthol with acetic acid catalyzed by various Brönsted acids were studied at 90-150°C without solvent. The mole ratio of acetic acid to menthol was 1 to 2. The estimated pK_a' values of the Brönsted acids in the reaction medium were larger by 5.4 than their pK_a's is aqueous solution. A reversible second-order rate constants (k, show n in Table 1) were proportional to O.7 th power of the estimated concentration of proton (Fig.3).

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The distribution, of heavy metals in the water of four lakes and in the brackish water within Mikata district, Fukui Prefecture, has been studied. The concentrations of copper, zinc, lead, cadmium, manganese and chromium were determined by atomic absorption spectrophotometry, after concentration by vacuum evaporation or by adsorption on chelating resin. The results obtained are given in Table 1, together with the corresponding data for the water of Biwa and Kitagata Lakes as well as for ordinary sea water. The average contents of each metal in the water of four lakes decrease in the order of manganese>>lead> chromium> cadmium >copper>zinc, and the concentrations of metals except manganese increase in the order of Mikata, Suigetsu, Suga and Kugushi Lakes, while that of manganese decreases. The averag e content of each metal in the water of Hiruga Lake is approximately within the concen tration range of ordinary sea water. Positive and negative correlations were observed between the several pairs of metals as shown in Figs.2 ( a ) and 2 ( c ), which are very closely related to the geographical features of these five lakes.

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In N, N-dimethylformamide (DMF), polychlorinated biphenyls gave dechlorination waves correspond to irreversible one electron per chlorine atom at the dropping mercury electrode.
The ease of dechlorination of each chlorine in PCB was evaluated by reduction potentials. Relationships between the bulk concentration of PCB and wave height of differential pulse polarograms correspond to dechlorination showed the linearity in the range of 5 X 10^-6 to 3 X 10^-3 mol/dm³.
The kinetic parameters of the dechlorination process were determined by cyclic voltammetry. kti= (1.1 4-1.46) x 10^-6 cm· s ^-1 and α O.2.
The present data indicate that mechan isms for the electrode reaction in DMF are as follows;
RCl_n + n e → Rⁿ. n Cl1^-
Rⁿ + nSH → RH_n + nS

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Optically active 1-benzyl-2-alkylaziridines [3] gave the corresponding cyclic dimers, (+ )-or (-) -1, 4-dibenzyl-2, 5-dialkylpiperazines [4]. The N-unsubstituted piperazines [5] were derived from [4] by hydrogenolysis. Every step of the reactions was considered to be retention of the configuration and (+)-cis-2, 5-dimethylpiperazine [5 a] was concluded to be S-configuration.

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The simple HMO approximation for an organic conjugated system was extended to include the coordination bond. As a measure of reactivity of methyl benzoate-metal complexes (the models for calculation) in the transesterification reaction, the superdelocalizability (S_γ^N) for nucleophilic attack was calculated.
It was found that _γ^N value (S₅^N) at a carbon atom in a carbonyl group was the largest for any metal ion. Plots of S₅^N values vs. logarithms of stability constants (log β₁), presented by the author as a measure of the catalytic activity of the metal compound in the formative reaction of poly (ethylene terephthalate), of dibenzoyl methane-metal complexes gave a straight line.

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