The reduced optical rotatory strengths (γ -ORS's) of twisted acrylaldehydes, (-) -lactic acids and their anions were calculated by means of the transformation technique of overlap integral, where the wave functions obtained by the CNDO/2 method were applied and the effects of configuration interaction were taken into account, The calculated valuse for the transoid (θ =10° ) of the twisted acrylaldehyde well fit the empirical Djerassi-Snatzke's rules, while that for cisoid (θ =170° ) is reverse of the result predicted by the empirical rules in sign, although its intensity is weak (Table 1). The present calculations reveal that the Djerassi-Snatzke's rule has many exceptions. In the case of the π -π r* transitions of the (-)-lactic acids some rotamers in which the intramolecular hydrogen bonds are formed, show negative γ -ORS, while the others have positive γ -ORS and high total energies (Table 2). Calculation for the anions of the (-)-la ctic acid shows that they do not give the results as seen in the (-)-lactic acids (Table 4). These facts are consistent with the CD spectra reported by Craig et al. (Table 3).

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The stable aqueous suspensions of magentite colloid were obtained by allowing anionic or nonionic surfactant to adsorb on the hydrophobic surface of colloidal magnetite prepared by monomolecular adsorption of oleate. It was found that sodium dodecylbenzenesulfonate, sodium oleate and poly (oxyethylene)nonyl phenyl ethers, whose HLB values being higher than 12, are suitable for giving a double adsorption layer to attain a stable dispersion. The change in the stability of co lloidal suspension with pH of the solution relates to the dissociation of surfactant of outer layer. Under the applied field of 5 kOe, the enrichment of concentration of dispersed magnetite colloid was not observed in this suspension and the suspension could be regared as a magnetic fluid. The magnetization in a constant magnetic field parallels the magnetite content of the suspension. The dependence of magnetization of the fluid on magnetic field was explained in terms of super-paramagnetism of the magnetite colloid. When colloid content of the fluid is increased to obtain a large magnetization, the fiber-like coagulated phase is partially formed in the suspension whose colloid content being more than 40 vol%. Finally, the suspension, whose colloid content being above 48 vol%, changes into gel-like aggregate.

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Sorption isotherms of benzene were measured at 0° for specimens of commercial silica beads which were compressed at a pressure range up to 20 t/cm² (Fig.1). The, isotherm fo r the specimen compressed at 3 t/cm² fairly agreed with the theoretical isotherm derived on the ba sis of the capillary condensation in a system where elementary particles of 4.0 nm in ra dius (R₀) are arranged in a simple cubic lattice-type packing. In the case of the spe cimen compressed, at 20 t/cm², the experimental result agreed with the theoretical one for a closest packing-type arrangement (Fig.2). The experimental results, whic h confirmed a corpuscular, structure of specimens, were Co-mparedw ith the experimental results obtained previously by the authors about Cab-o-sil and carbon blacks (R₀ ≥ 10 nm) and those of Avery and Ramsay who used silica and zirconia of 2.0 nm in radii., The compressed specimens became denser with decreasing size of elementar y particles;, The isotherm was of BET-I type when R₀ was less than 4 nm and the specimen was compressed at a high pressure. These results indicate that the isotherms are de termined by the pore size distribution of the specimens. A slight decrease in specific su rface area (Table 1), was explained by Eq ( 1 ), derived by Avery and Ramsay on the assumption that adsorbate molecules cannot intrude into a part of contact zones between elementary particles.

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Addition reaction of sodium hydrogensulfite to allyl alcohol was initiated by γ -rays in an aqueous sodium sulfite buffered solution. The rate of disappearance of sodium hydrogensulfite, which is equal to that of allyl alcohol, is proportional to the concentration of hydrogensulfite ion and varies inversely with the concentration of allyl alcohol. Chain termination reaction was deduced as follows: HOCH₂CHCH₂SO₃^- + CH₂=CHCH₂OH → HOCH₂CH₂CH₂SO₃^- + CH₂=CHCHOH The apparent rate constant of sodium hydrogensulfite consumption was calculated to be 1.28x10^-5 exp (1.66 x 10³/RT) mol/l· sec at a dose rate of 6.4 0x 10¹⁵ eV/g· sec.

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The isomerizations of normal butenes have been studied at 130-250° C over two kinds of aluminium phosphates; one (AP-I) prepared from α -alumina and phosphoric acid and the other (AP-II) prepared from aluminium chloride and phosphoric acid. The reaction products were all normal butenes and no skeletal isomerizations were observed. The catalytic activity of AP-II which showed a high acid strength of H₀≤ -8.2 was much higher than that of API which showed a weaker acid strength of H₀> +0.8 (Table 1 and 2). The activities of two catalysts were reduced by poisoning with NH₃ but not altered by CO₂. The activity of API was decreased by about 50% with an excess amount of NH₃, while that of AP- II was lost completely with 0.24 mmol/g of NH₃ (Fig.1). The nature of sites for the isomerization of butenes and the adsorbed states of butenes were discussed on the basis of the distributions of deuterium atoms in the products which. were obtained from cis-2-butene over deuterium exchanged catalysts (Table 4).

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The feasible reaction mechanism and the effects of operating variables on the liquid-phase oxidation of carbon monoxide have been investigated in a stirred reactor by using aqueous solutions containing CuBr₂, FeBr₃, and PdBr₂ as catalysts. The catalytic activity due to PdBr₂ is higher th an that due to PdCl₂ and the over-all rate can be represented by the equation r=k[Pd(II)]^1.1· [CO]^1.7. The rate expression seems to support the mechanism including four coordinated square complex of palladium [Pd(C0)₂Br₂]as an intermediate of this reaction. The influence of the stirr ing rate N on the interfacial area a or the liquid-phase mass transfer coefficient K_L* has also been studied in terms of the film and surface-renewal theory in the rate-determining range in which at lower concentration of carbon monoxide the rate being affected by both diffusion and reaction. The results of the present study are in agreement with those of the published reports.

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Nickel-phosphorus (Ni-P) catalyst was prepared by heating a basic solution of sodium phosphinate containing dispersed Ni (OH)₂ at 50° C in nitrogen atmosphere. The vapor-phase hydrogenolysis of benzyl alcohol at 160-180°C over this catalyst was carried out using a flow reactor at atmospheric pressure. The main products were toluene and benzaldehyde. The toluene formation activity of the crystalline Ni-P catalyst ob tained by heating the amorphous catalyst was about zero at the beginning of the reaction, but increased rapidly with time and exceeded a constant activity value of the amorphous catalyst (Fig.1). The catalysis over the crystalline catalyst was kinetically investigated (Fig.2 and 4). The formation of toluene was the first-order with respect to hydrogen and the zeroth-order with respect to benzyl alcohol, and the activation energy was 22.4 kcal/mol. The rate of formation of benzaldehyde was almost zero, but the mole ratio of benzaldehyde to benzyl alcohol, x_B /x_A, during the reaction increased to get a constant value depending a given temperature (Fig.6). These results and the reaction scheme given by eq.3 with the assumption that the caverage of adsorbed benzyl alcohol is approximately unity and the rates of desorption and adsorption of benzaldehyde are nearly equal led the following conclusions. The rate determing step of toluene formation is the reaction of adsorbed benzyl alcohol with hydrogen. The x_B /x_A, ratio is proportional to the coverage of benzaldehyde (eq.15), which increases with the rate of the surface reversible oxidation of adsorbed benzyl alcohol into benzaldehyde.

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The vapor-phase hydrogenation of benzaldehyde at 160-180° C over nickel-phosphorus (Ni-P)catalyst was carried out using a flow reactor at atmospheric pressure. The main products were benzyl alcohol and toluene, but the amount of benzene as a by-product was lager than in the hydrogenolysis of benzyl alcohol over the same catalyst. The crystalline Ni-P catalyst obtained by heating the amorphous catalyst took longer time to be activated than the case of the hydrogenolysis of benzyl alcohol (Fig.1). The difference in the length of time required to activate the catalyst, presumably indicates that benzyl alcohol activates the catalyst. The hydroge nation of benzaldehyde and benzaldehyde-benzyl alcohol mixture over the crystalline catalyst were kinetically investigated (Fig.2, 3 and 4). The rates of the decrease of benzaldehyde (-γ _B) and the formation of benzyl alcohol (γ _A) and toluene (γ _T) could be represented by equations 4-6, derived from the reaction scheme (eq.1) with assumption that the reactions of very strongly adsorbed benzaldehyde and benzyl alcohol with hydrogen are rate-determing steps.

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In the solutions containing both oxygen and any one of the bis (1, 3-diketonato) cobalt (II)complexes, Co (HFA)₂, Co (FTA)₂, Co (BFA)₂, Co (fod)₂, Co (TAA)₂, Co (TTA)₂, Co (PTA)₂, Co (AA)₂ and Co (DPM)₂, a new polarographic reduction wave was observed at about 0.65 V vs. SCE. The variation of height of this new wave was investigated as a function of concentration of the above complexes. An increase in concentration of these complexes brings about an exaltation of catalytic current, due to the regeneration of oxygen on mercury electrode. Electrolysis at constant potential affords an information about the reduction process in the presence of Co (AA)₂ complex. As a result, the following reaction was presumed to occur on the mercury electrode: 2Co(AA)₂O₂^- → [(AA)₂CoO₂Co(AA)₂]^2- + O₂Moreover, the rate constants of the regeneration of oxygen we re determined.

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In order to obtain further details concerning the mass transfer rate at the wall jet electrodes, the behavior of limiting diffusion current at wall jet ring electrode was examined. From the general equation of the limiting diffusion current in hydrod ynamic voltammetry, the limiting diffusion current at the wall jet ring electrode derived as I_d= 1.60nFC⁰D^2/3ν ^-5/12V^3/4a^-1/2[R_oR^9/8-R_iR^9/8]^2/3The theoretical prediction for the dependence of the limitin g diffusion current upon various experimental variables, i. e., the bulk concentration of depolarizer (C⁰), the volume flow rate (V), the diameter of the nozzle (a), the outer and the inner radius of the ring electrode (R_o and R_i), etc., was verified experimentally, using the carbon paste ring and the gold ring electrodes as an indicator electrode. Finally, the validity of the numerical coefficient in the theoretical equation was examined.

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Powders of commercially available calcium hydrogenphosphate dihydra. te (CaHPO₄· 2H₂O) or magnesium hydrogenphosphate trihydrate (MgHPO₄· 3H₃O) (composed of particles ranging 1 100, μ in diameter) were immersed in copper (II) sulfate or copper (II) chloride solutions containing 100-2500 ppm of Cu (II) for 0-48 hrs at room temperature and adsorption ability and mechanism of Cu (II) were investigated by measuring amounts of Cu (II), Ca (II) or Mg (II)and P (V) in the residual solutions and by analysing X-ray diffraction patterns of the powde rs before and after adsorption. The results were as follows: 1) Although the powders dissolved a little into solution, the adsorption progressed with processes, in which the powders changed to Cu (II) containing insoluble phosphates in the solution of pH range 3.0-7.0.2) When they were immer s ed in the solutions containing 1500 or 2500 ppm of Cu (II), their uptakes of Cu (II) were fairly larger than those of other phosphates and commercial adsorbe nts, and their values both amounted to about 7.0 meq Cu/g.3) The adsorption mechanism of the powders im mersed into the copper (II) chloride solutions was explained with following formulas. MgHPO₄+ Cu²⁺ + 2Cl^- → CuHPO₄+ Mg²⁺ + 2Cl^- ( 1)(Ca) (Ca2+)2CuHPO₄ + Cu²⁺ + 2Cl^- → Cu₃(PO₄)₂ + 2H⁺ + 2Cl^- ( 2 )When there are excess Cu (II) in the solution, CuHPO₄·H₂O produced by reaction ( 1 ) is instantaneously converted to Cu₃(PO₄)₂· 3H₂O by capturing excess Cu (II) by reaction ( 2 ). However, when the amounts of Cu (II) in the solutions decrease until a certain value by adsorption, only the reaction ( 1 ) proceeds again as in the solutions of low Cu (II) concentrations.

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Dehydration and transformation of CaSO₃· 1/2 H₂O after firing were investigated by IR, DTA and X-ray. The processes are different from those found in the previous tests. IR spectra were measured by KBr method in the range from 4000 to 400 cm^-1.
The results are summarized below: ( 1 ) The existence of CaSO₃· 2H₂O was not recognized as shown Figs.2 and 3.
( 2 ) The hydrogen bonds are formed between SO₃^2- and H₂O.
( 3 ) Water of crystallization of CaSO₃· 1/2 H₂O is nearly lost at 470° C as shown Fig.4.
( 4 ) Characteristic absorption bands due to S-O, S=O stretching vibrations and O -S- O
bending vibrations are split into several bands in the range of these temperatures as shown Table 2, Figs.5, 6, 7, 8 and 9. The existence of III β -CaSO₄ was recognized during the course of transformation from CaSO₃· 1/2 H₂O to II CaSO₄. It may be concluded as follows:
CaSO₃· 1/2 H₂O 335°C → [CaSO₃(δ H₂O) + IIIβ - CaSO₄(δ H₂O)]
382-401°C → [CaSO₃(δ H₂O) + II CaSO₄]459-470° C → II CaSO₄ → I CaSO₄
( 5 ) The temperature range in which CaSO₃· 1/2 H₂O completely disappears and transforms to II CaSO₄ alone by firing is 459-470° C.

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The thermal decompositions of formates of Li, Na, K, Rb and Cs were investigated by thermogravimetry. (1) Form the results obtained, alkali metal formates decomposed by the following two stages. First stage; 2HCOOM → H₂+CO+M₂CO₂ (a) → H₂+M₂C₂O₄ (b)Second stage; M₂C₂O₄ → CO + M₂CO₃ (c)In spite of the fact that alkali metal formates decomposed at lower temperatures than those of respective oxalates, conversion to oxalate (reaction b) became more favorable with the increase of thermal stability of respective oxalate. ( 2 ) The decomposition of alkali metal formate was initiated by the C-H bond breaking. Since the electronegativity could be correlated with the C-H bond nature, the relationship between the H3 evolving temperature and electronegativity of alkali metal was discussed. ( 3 ) Oxalate was mainly formed at the higher temperature range of the first stage. The conversion to the oxalate was prevented by the oxygen in flowing air. Also, amorphous carbon formed in the first stage prevented evidently the conversion to oxalate in a similar manner as heavy metals, Co, Ni, Cu and Pt.

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Solid solubility curves of isomorphous oxide binary systems were estimated by the assumption of the regular solution. The solubilities of the system were obtained by the equal tangents method through the calculation of Gibbs energy of mixing, δ mG(x)=δ mH*(x) Tδ mS^id(x), where δ mS^id the entropy of ideal mixing, and δ mH* is the enthalpy of mixing. δ mH* is dependent on the lattice energies (U), the averaged bond lengths (r) and the electronega tivities (X) of the end components. δ mH*(x)= B-x₁x₂(U₁r₁-U₂r₂)²/B / r+x₁x₂{0.2(r₁r₂)²/r-0.04(x₁-x₂)^2r}-x₁U₁-x₂U₂In this expression, r = x₁r₁+x₂r₂, and B= x₁U₁r₁+x₂U₂r₂, where x is a mole fraction and subscripts 1 and 2 denote the first and the second components respectively. Good agreement between estimated values and experimental solid solubility curves or consolute temperatures was found for the systems of MgO-CaO, Al₂O₃-Fe₂O₃, CaTiO₃-BaTiO₃, Na₂SO₄-Na₂MoO₄ and NaNO₃-KNO₃, for which experimental data had been available.

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A new compound, potassium lithium hexatitanate, was synthesized by the hydrothermal reaction of titanium dioxide with potassium hydroxide and lithium hydroxide. The compound is rhombic bipyramidal crystals of as far as few mm in length mixed with fine particles of lithium titanate and fibrous potassium titanates. The reaction proceeded in highest yield under the following conditions: TiO₂: LiOH: KOH= 1.5: 1.0: 7.5 (in molar ratio); concentration of alkali=10N; filling of solution= 35-45%; temperature ≥ 400%deg;C; time of run ≥ 70 hrs.
Potassium lithium hexatitanate is not produced through the direct reaction of titanium dioxide with potassium and lithium ions, but through the reaction of lithium ion with potassium hexatitanate already formed.
The crystal structure of potas sium lithium hexatitanate has been determined by three dimensional X-ray intensity data.
The crystal is ortho rhombic with space group F 222, whose unit cell dimensions being a=16.43 Å, b= 5.80 Å and c=11.28 Å and has four units in the cell. The observed and calculated densities are 3.69 and 3.73 g⋅ cm^-3, respectively. The distorted TiO₆ octahedra are connected with each other by corner and edgesharing to form a three dimensional framework and the large interstitial openings are occupied by the alkali-metal atoms.
Potassium atoms are surrounded by ten oxygen atoms of TiO₆ octahedra.

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Long foshagite fiber was synthesized hydrothermally from a mixture of Ca(OH)₂, and SiO₂at a constant temperature of 400° C under water vapor pressure of 120 to 230 atm for a week at longest, using alkali hydroxides of the concentration of O.5 to 4 N as mineralizers. When 0.5 N NaOH was used as a mineralizer, long foshagite fibers wer e prepared in a good yield. There was a tendency for the length of the fiber to decrease with an increase in the concentration. Short foshagite fibers with maximum length of 0.6 mm together with other minerals were obtained in a poor yield in the case of LiOH. Especially in KOH, the dimensions o f fibers with the maximum length of 1.8 cm were relatively uniform and the yield increased with an increase in the concentration of mineralizer. The effect of concentration on the product yield was in the order; 4 N> 2N > 0.5 N > 1N. A possible change in the coordination numbers of K⁺, Na⁺ and Li⁺ ions in foshagite str ucture under high pressure and high temperature is considered to be responsible for the effect of the variety of mineralizer on the nature of the fibers. The synthetic foshagite fiber was found from their X-ray and electron diffraction data to have high crystallinity. From the result of infrared spectroscopy, two absorption bands near 3600 cm^-1 of IR were attributed to the sio, stretching vibrations. The synthetic foshagite contained 0.1 to 0.2 per cent alkali metal by weight.

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Monazite powder obtained by heating hexagonal cerium phosphate at 800° C for 2 hours was pressed into pellets of about 10∅ x 5 mm in size under the pressure of 500 kg/cm² for a few minutes. The green bulk density of the pellet was 2.54 g /cm³. These pellets were fired in the temperature range 900° C to 1500° C for 5 to 200 minutes in air. Pellets began to sinter at 950° C. The bulk density of the pellet fired at 1500° C for 15 minutes was 5.0 g/cm³ which was 97% of the theoretical density (5.16 g/cm³) (Fig.2). The slope of the curves obtained by plotting logarithm shrinkage rate vs. logarithm firing time at the initial-stage sintering was O.4 (Fig.3). Grain began to grow at 1100° C. The grain growth in the temperature range 1200° C to 1500° C followed well-known equation D²= Kt (Fig.5). The coefficient of linear thermal expansion was 9.9 x 10^-6 (-1000° C) for the pellet fired at 1500° C for 60 minutes (Fig.6), and no crack was observed after 20 times of the thermal shock test by quenching and reheating in the range 20° C to 800° C (Table 1). The freezing point of the synthetic monazite was 2045± 22° C (Table 2).

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The complexation of nickel (II) with dimercaptomaleonitrile (maleonitriledithiol, H₂mnt or H₂L) has been studied and applied to the spectrophotometric determination of trace amount of nickel. Temperature and ionic strength were maintained at 25 ± 0.1° C and at O.3 (with KCl), respectively, for the equilibrium studies. H2mnt (H₂L; pK_a1, < 2 and pK_a2 = 3.92± 0.02) reacts with nickel (II) to form a water soluble stable complex, NiL₂^2- (log β ₂ = 21.84± 0.21), in the pH range from 2.5 to 12.0. Aqueous solution of the complex has an absorption maximum at 312 nm with a molar absorptivity of 2.76x 10⁴l / mol. cm (Fig.1 and Table 2). Although the free ligand is markedly oxidized by air, zinc (II) ion can successfully stabilize it by forming two kinds of stable complexes, ZnL (log K₁=6.86 ± 0.09, ε ^335nm_max=1.12 X 10⁴ l/mol⋅ cm) and ZnL₂^2-(log β ₂= 15.07 ± 0.14, ^335nm_max = 1.76x10⁴ l/mol⋅ cm), (Fig.1 and Table 2). The difference in the absorption spectra (δ ε ^312nm = 2.4x10⁴l/mol⋅ cm, see Fig.1) as well as that in the stability constant (δ log β ₂= 6.77), seem to be large enough to apply the system, metal exchange reaction (ZnL₂^2- Ni²⁺ NiL₂^2- Zn^2-) for the. spectrophotometric determination of nickel. Under the condition of the recommended. procedure, the exchange reaction proceeded quantitatively within 15 minutes and the absorbance was effectively constant for 4 hours. Beer's low was confirmed in a range of 0-44 μ g Ni²⁺/25 ml and the sensitivity for log (I₀/I) =0.001 level was 2.4 x 10^-3, ug Ni²⁺/cm². Amoung 12 metal ions studied, iron, cobalt, and copper seriously interfered with the determination of nickel. Recommended procedure is as foll ows; take the sample solution containing less than 44 μ g of nickel(II) in a 25 ml volumetric flask. Add 5 ml of 7.5 X 10^-4 mol/l ZnL₂^2- solution and 2.5ml of 0.1 mol/l hexamine-HCl buffer (pH 5.1) and dilute to the mark with water. Stand for 30 minutes and measure the absorbance at 312 nm against the reagent blank.

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A tensammetric wave of the oxidative dimerization product of o-aminophenol was used for the catalytic analysis of an extremely small amounts of copper (II) ion. o-Aminophenol is oxidized slowly by dissolved oxygen and forms 3 -arninophenoxazin-2-ones in pH range from 6 to 8. In A. C. polarography, o-aminophenol is inactive but its oxidation product gives a very sensitive tensammetric wave, as shown in Fig.1. From the r esults of the measurements of electrocapillary curves, temperature coefficients of A. C. wave height an d the relation between A. C. wave height and the concentration of the oxidation product (Langmuir type relation), it was conclude4 that the first A. C. wave has a tensammetric natur e. As shown in Fig.6, Cu (II), Ag(I), Mn (VII) and Ce (IV) ions enhance markedly the rate of the oxidation of o-aminophenol. Among these cations, a very small amounts of copper (II)ion catalyzes the oxidative dimerization r eaction of o-aminophenol with dissolved oxygen according to the equation ( 2 )-( 4 ). Chloride ion greatly improves the t e nsammetric wave height, because copper (I) ion formed by the oxidation reaction of o-aminophenol is stabilized by chloride ion and the cyclic re action proceeds smoothly. The op t i mum conditions on the determination of copper (II) ion from 0.15 to 3.2μ g in 50ml final solution is as follows: o-aminophenol, 2 x 10^-5 mol/l; sodium chloride, 0.02 mol/l; buffer system, 0.04 mol/l sodium borate-acetic acid buffer; standing time, 2 hours; pH 8.0 and temperature, 30° C. The interfer e nce of various ions was studied. Of these, CN^-, Mn(VII) and a large amounts of Ce (IV), Ag(I) and Hg (II) ions interfere with this method.

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Rapid analysis of fatty acid glycerides (tri-, 1, 3-di, 1, 2-di and 1-mono) was carried out (in Fig.2) by high speed liquid chromatography (HLC) under the following conditions; ZorbaxSIL column: 2.1 mm i. d. x 50 cm (connected two 25 cm columns), mobile phase: mixture of acetone and hexane (gradient rate, 5% acetone/min), temperature: 45° C, pressure: 2000 psi, detector: modified moving wire/flame ionization detector. Eluted components were determined by both internal standard method (cholesterol internal standard) and calibration factor method (1-monostearin was stand to 1.00). Results obtained by two kinds of methods coincided well each other. Science the latter method was more simple compared with the former method, the calibration factor method was applied to the practical analysis of five commercial monoglyceride concentrates. The soaps and free fatty acids in samples were eliminated by ion exchange pretreatment. As little as 10% triglyceride in sample could be determined by the proposed HLC. This concentration of triglyceride could not be determined by the conventional GC as shown in the analysis of sample A and B.

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Gel beads, which consisted of outer crosslinked poly (vinyl alcohol) and inner poly (vinyl acetate) layers, were prepared by partial saponification of poly (vinyl acetate) beads, followed by crosslinking of the outer layer by means of γ -ray irradiation or treatment with epichlorohydrin. The appropriate arrangement of saponifier amounts and saponification time gave gels which had a suitable thickness ratio of outer layer to that of inner layer. Gel beads, which consisted of outer crosslinked poly (vinyl alcohol) and inner linear poly (vinyl alcohol) layers, were prepared by saponification of inner layer of the above mentioned gel beads. By eluting a mixture of homologous polymers through the column packed with poly (vinyl alcohol) gel beads with a double layer structure, polymers of high molecular weight were excluded from gel beads and polymers of low molecular weight penetrated into gel beads. As a result, the polymers were fractionated into two groups. This extraordinary behavior of elution appeared in the case, where a thickness ratio of outer layer to that of inner layer of a gel was small and outer layer of a gel was crosslinked while inner layer was not crosslinked or crosslinked only slightly compared with outer layer. This process may be considered as a special case of gel permeation chromatography, at which the distribution coefficient K_d, equals zero or unity.

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Polarography using a rotated dropping mercury electrode as an indicator electrode was utilized as a selective detector for gas chromatography. Chromatographic effluent was dispersed continuously in the electrolyte solution (refer to Fig.1) through a fine stainless-steel capillary tube connected to the chromatograph outlet and electrolytic current was detected at a constant applied potential. This detector gives an integral response and the chromatogram consists of a series of steps. This detec tor system was applied to the determination of nitrobenzene in aniline and nitrophenol isomers. The limit of detection was found to be 1 ppm and the linear dynamic range was about 1 x 10³ (10^-4-10^-7 g) for nitrobenzene. The system had several advantages; 1)deoxygenation of electrolyte solution was performed by carrier gas from the chromatograph, 2) irregularity of the mercury drop caused by dispersing the effluent in the electrolyte solution was minimized, 3) rotation of the electrode made the effluent concentration homogeneous in electrolyte solution instantaneously and 4) the limiting current of the rotated dropping mercury electrode was found at least 10-15 times greater than that of the conventional dropping mercury electrode. This electrochemical technique offered attractive application. For instance, the determination of electrochemical active minor componenent in non active major ones and the selective detection of a specified component in multicomponent sample being difficult to separate into each other by gas chromatographic column can be done successfully.

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“ Resin Spot Test” method was applied to the detection of a minute quantity of CN^-, SCN^-, Fe (CN)₆^3- or Fe (CN)₆^4-. Strong basic anion-exch ange resin particles of MR type (Diaion PA-304 [Cl] and Amberlite IRA-900 [Cl]) were found to give excellent results for the detection of these ions.1) Detection of CN^- with pyridin-pyrazolone reagent: A drop of the test solution, a drop of the buffer solution whose pH being 6-8 and containing 0.03% chloramine-T (refer to 2.1.4)and a drop of the 0.1% pyridin-pyrazolone reagent were mixed on a spot plate, and a few particles of the anion-exchange resin were added to them. After a while, the CN-color prducing reagent was adsorbed on the resin particles. Blue to pale-blue color appeared on the surface of the resin particles. The limit of identification was 0.003μ g, and the dilution limit was 1: 10⁷.2) D etection of SCN^- with FeCl₃: A few particles of the anion-exchange resin were mixed with a drop of the neutral or slightly acidic test solution on a spot plate in order to concentrate SCN^- on the resin particles. To these resin particles a drop of the reagent solution (0.1mol/l FeCl₃ in 3N HCl) was added. After 5-10 min, reddish-orange to yellowish-orange color appeared on the resin particles. The limit of identification was 0.01μ g, and the dilution limit was 1: 3 X 10⁶. CN did not interfere with the test.3) Detection of Fe(CN)₆^3- or Fe(CN)₆^4- with FeSO₄: A few particles of the anion-exchange resin were mixed with a drop of the neutral or slightly acidic test solution on a spot plate in order to concentrate Fe(CN)₆^3- or Fe(CN)₆^4- on the resin particles. To these resin particles a drop of the reagent solution (0.1 mol/l FeSO₄ in 10% hydroxylammonium chloride) was added. After about 30 minutes, blue to pale-blue color appeared on the particles. The limit of identification was 0.01μ g, and the dilution limit was 1: 3x 10⁶. CN^- and SCN^- did not interfere with the test. The abo ve results could be used for the detection of these ions contained in the test solution as a mixed state.

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From the measurements of polarized absorption spectra using stretched polymer films and PPP calculations, we determined the polarization direction of each electronic transition of 1and 2-naphthalenethiol and discussed the influence of the mercapto group on π -electronic systems. The empirical parameters of the mercapto group required for the PPP calculations were estimated as follows: The second ionization potential of the sulfur atom has been approximated by I_p(S⁺) =I_p(S) + (SS|SS) =22.3 eV, where I_p(S) is the first ionization potential of the sulfur atom. The resonance integral between carbon and sulfur atoms, β _CS, was assumed from the results of the polarized absorption spectrum; the optimum value of β _CS was -2.8 eV. The results of the PPP calculations by use of the empirical parameters obtained here were in good agreement with the observed ones. The magnitude of the resonance effect of the mercapto group on 7r-electronic systems was compared with those of the other substituents (amino group etc. ). The order of the magnitude of the resonance effect was as follows; -0H < -SH < -NH₂ < -O^-.

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Nitrations of N-trifluoroacetyl aromatic amines (Ar-NHCOCF₃) were studied in comparison with those of N-acetyl aromatic amines (Ar-NHCOCH₃). The substituent -NHCOCF₃ was an 0, p-orienting group in analogy with the substituent -NHCOCH₃ in nitrations of ArNHCOCF₃ (Ar = phenyl or naphthyl groups) (Table 2). However, these substituents showed the reverse orienting influences in nitrations of p-RCONH-biphenyl ([C9]; R=-CF₃, [9']; R =CH₃), 2-RCONH-fluorene ([12]; R=CF₃, [12']; R=CH₃), and 3-RCONH-dibenzofuran ([13]; R=CF₃, [13']; R = CH₃) (Table 3). These curious effects of the substituent -NHCOCF₃are considered to be due to the interaction between inductive effects, resonance effects, and the electrostatic repulsion induced in the course of the ortho attack.

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p-Nitroaniline [1] is ionized by t-BuOK in hexamethylphosphoramide (HMPA) to form p-nitrophenylamide ion, which gives rise to nucleophilic substitution with nitrobenzene derivatives [2 a-g]. We have found two types of the nucleophilic substitutions; the one with the substituent of [2 a-g] and the other with the aromatic hydrogen atom. The latter, occurring in the ortho or para position to nitro group of [2 a-g], was recognized in almost every reaction under various conditions. In the former type of the reaction, the meta substituent was not affected, but the ortho or para substituents were favorably displaced. Under such conditions as give rise to both types of the substitutions, the former type of the substitution was predominant when less amount of t-BuOK was used. On the other hand, the latter type of the substitution preferably proceeded when much amount of t-BuOK was used. The mechanisms of both types of the substitution are suggested from the structure of products and results of the measurement of ESR.

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Treatment of phenylacetonitrile with nitrobenzene in 50% aq. sodium hydroxide in the presence of benzyltriethylammonium chloride (TEBACl) as a phase-transfer catalyst gave 1-anilino-2cyano-1, 2-diphenylethylene [11], (p-nitrophenyl) phenylacetonitrile [2] and 4- (a-cyanoben zylidene)-2, 5-cyclohexadien-1-one oxime [3]. The yields of [1], [2] and [3] J changed considerably by varying the amount of TEBAC1 and the concentration of sodium hy droxide solution. In the absence of TEBACl only a trace amount of [3] was formed. By adding a ca.1.5 molar excess of TEBAC1 relative to phenylacetonitrile, [1] and [2] were formed selectively. The synthesis of [2] from phenylacetonitrile and nitrobenzene is the first example of nucleophilic substitution of such aromatic compound by a carbanion. [ 1] and [2] were assumed to be formed by a sort of electron-transfer process, while [3] by an ionic reaction.

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Isothiazolone [5] has been obtained in good yields by the reactions of penicillin S-oxide with pyridinealcohols. The reaction with 3-pyridinol also gave [5] in a good yield, but the reactions with pyridine, .2- and 4-pyridinol resulted in very low yields, of [5]. These results seem to be attributed to the pyridone structures of pyridinols and imply that hydroxyl g roup may be playing an important role in the formation of isothiazolone. The isothiazolone has also been prepared in good yields in the presence of 1-morpholineethanol, 1-piperidineethanol and triethanolamine. In the presence of primary a n d secondary amines containing hydroxyl group, the isothiazolone can not be isolated. Since thes e amines have a relatively active NH₂- or NH- group, many side reactions are considered to take p lace. A concerted mechanism through the cyclic intermediate can be proposea. The initial path of the reactions seems to be the abstraction, of a proton base followed by the formation of t he cyclic intermediate through the interaction of the hydroxyl group with the sulfenic acid derived from penicillin S-oxide. The reactions o f penicillin S-oxide with pyridinealcohols-phosphoric acid salts are also discussed.

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The layer stacking and the optically anisotropic texture of a mesophase were clarified by using X-ray diffractometric and microscopic methods. The mesophase was obtained from four kinds of starting materials: coal tar pitch (KA), virgin reduced crude (SL), poly (vinyl chloride) (PVC) and 3, 5-xylenol-formaldehyde resin (XF), by heat-treatment of various residence times up to 24 hr at fixed temperatures (370 or 430° C). The mesophase obtained by a long time heat-treatment contains 40-50% of the total carbon atoms in its layer stacks (Fig.11). The average stacking. units are consisted of about 3 layer planes (Fig.9, 10) and locate at the intervals of 15-25Å each other (Fig.4). The parallel alignment of the stacking units in the c-axis direction becomes much better when the optically anisotropic texture in the mesophase develops uniformly in wide region and results a fibrous pattern.

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Copolymerization of ahydrophilic monomer, 2-hydroxyethyl methacryIate(HEMA), wlth a hydrophobic monomer, styrene(St) or methyl methacrylate(MMA), was studied. In the case of HEMA-MMAsystem, copolymer composition was determined by NMR spectra in pyridine. Monomer reactivity ratios were determined as given in the following table. HEMA-St γ ₁(HEMA)0.85 γ ₂0.33HEMA-MMA γ ₁(HEMA)0.66 γ ₂0.86Films of copolymers andb lendmers were cast from DMF solutions. They make contact angles with water. In the case of blendmers, contact angles vary graduaUy with composition. Contrary to blendmers, contact angles of copolymers rernarkably change with HEMA mole fraction to bring about a rise of about 0.8 in HEMA-St system, and about O.5 in HEMA-MMA system. The difference in wettability between copolymers and blendmers was considered to benatural, since hydrophilic and hydrophobic functions were influenced not only by the composition but also by the microstructure to the polymers.

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Seven alkyl ketones (AVK, M₂) were synthesized and copolymerized with styrene (St, M₁). Although AVKs have two stable conformers, s-cis and s-trans capable of existing in all proportions, the reactivity ratio r₁ is nearly the same. Copolymerization parameters, Q and e, except those of t-BuVK and PhVK, which are preferentially the values for s-cis conformation, parallel the Taft's σ * values of the alkyl groups, as shown in the equation ( 1 ) and ( 2 ). Q= 0.87 σ * + 1.25 ( 1 )e= 0.29 σ * + 0.69 ( 2 )The reactivity ratio r₂ of t-BuVK (2.42) is much larger than those of other AVKs (0.450.60). This fact could be explained in terms of the steric hindrance in the polymerization. The Q and e values of t-BuVK, which are distinctly different from those of other AVKs, were considered to be the values for s-cis form.

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Mechanochemical reaction which is caused by the complexation between poly (methacrylic acid) (PMAA) network and poly (ethylene glycol) (PEG) was studied. It was found that the water swollen PMAA membranes, suspended with 490 mg of load over the embedding fluids (70 ml of water) containing PEG, make reversible contraction-dilation with increasing-decrea sing temperature. Changes in length of the membrane, for example, 4.7 mg of dry membrane, to which a load of weight 100 times the weight of the membrane was attached, go up 90%(in respect to the length of the dry membrane) in the temperature range of 10 to 40°C. The temperature region in which the mechanochemical reaction proceeds most efficiently can be regulated by changing the PEG concentration in the embedding fluid. It was also found that the dependence of contraction-dilation on the change in temperature can be reversed by the addition of a small amount of ethanol to the embedding solution of PEG (i. e., increase in temperature results in dilation of the membrane).

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Stability constant (K) and degree of complexation (θ ) in the complex formation between poly (methacrylic acid) (PMAA; mol. wt.66000) and poly (ethylene glycol) (PEG) with various molecular weights were determined by means of potentiometric titration. It was found that PEG (mol. wt.2000) is capable of forming the complex in higher temperature range. At 55° C, K and θ become about 500 and O.6, respectively. Further rise in temperature brings about a redissociation. PEG (mol. wt.3000) forms more stable complex (K=1000, θ = O.7) and never dissociates in the same temperature range. PEG with high molecular weight (7500, 20000)can form a stable complex even at a temperature as low as 10° C and the stability of the complex is slightly affected by the change in temperature. In terms of the data of standard enthalpy change or entropy change, it was found that the complexation is endothermic and proceeds with an increase in entropy.

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Isotactic polypropylene was treated with hot air without chain scission, resulting in good bondability. Organic dicarboxylic acids having 0-8 methylene linkages were added to polypropylene, and subjected the same treatment, resulting in maximum value of peel strength between 2-4. Under the same conditions, minimum value of the spherulite diameter and maximu m value of reflection intensity on (040) surface by X-ray diffraction pattern were also observed.

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Performance of double cylinder type thermal separation column has been studied with regard to the effect of inclination of column setting. Three columns of different radial size and length were constructed to compare the performance. Equimolar mixture of Ar-N₂ was used as the test gas. It was ascertained, in accordance with theory, that when K_d was greater than K_c a larger equilibrium separation was attainable and that when K_c was much greater than K_d only a small separation was attained. The rate of approach to equilibrium was, however, inversely related to the extent of equilibrium separation. Inclination of the column was effec tive for columns having greater K_c than K_d. When K_dexceeds K_c the effect of tilting was always negative regardless of angle of inclination. The effect of tilting was attributed, at least qualitatively, to the depression of convectional velocity caused by the decrease in effective gravitational force. An attempt to visualize the flow patterns in th e inclined cylinder was also described.

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The densities of dilute aqueous solutions of 1, 1, 3, 3-tetramethylbutylammonium chloride and sodium 3, 5, 5-trimethylhexanoate have been determined at 5, 25, and 45° using a buoyancy technique. The apparent and limiting partial molal volumes of the salts have been derived. The partial molal volume of branched-chain isomer is smaller than that of corresponding straight-chain isomer as well as the calculated value. The results have been compared with those for the isomeric butylammonium and butanecarboxylate salts. The effects of hydrophobic and ionic groups on the structure of water have been discussed.

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The only product isolated from the reaction of guaiazulene with mono-, di- or trichloroactic acids in the presence of iron(III) oxide and potassium bromide as catalyst has been proved to be 3-(7-isopropyl-1, 4-dimethylazulene)acetic acid. When anhydrous aluminium chloride was used in place of iron(III) oxide and potassium bromide, only a trace of the product was obtained.

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Primary aromatic or aliphatic amides were allowed to react with tris(diethylamino)phosphine P(NEt₂)₃ under reflux in THF to give the corresponding nitriles in good yield with the evolution of diethylamine. Similarly, thiobenzamide reacted with P(NEt₂)₃ more readily than benzamide and was converted into the nitrile quantitatively. In the case of aliphatic amides, the yield of nitriles de creased with the increase of the number of carbon atoms. The dehydration reactions using other phosphine compounds P(NMe₂)₃, PCl₃, P(OEt)₃, , PPh₃were also described in the next.

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2, 4-Dinitro-1 (heptafluoroisoproyl) benzene was catalytically hydrogenated in the presence of hydrochloric acid to give 1- (heptafluoroisopropyl) -2, 4-phenylenediamine dihydrochloride, which was subsequently phosgenated to 1- (heptafluoroisopropyl) -2, 4-phenylene diisocyanate. Polyurethane elastomer was prepared from this diisocyanate and poly (oxypropylene) glycol. The introduction of heptafluoroisopropyl group scarcely brought about an effect on thermostability of polyurethane, but it gave inflammability.

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Tetraflurophthalimide [2] underwent self-condensation in the presence of alkali or potassium fluoride in aprotic polar solvents. The product was perfluorooligoimide, [4] (n=2-3), mp > 360° C, carrying a terminal dicarboxyl group, and was readily soluble in aqueous alkali. Several reactions of [2] and its derivatives were carried out to establish the structure of [4].

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