Microwave spectra of three isotopic species of t-butyl nitrite were assigned between 8.5 and 32 GHz, and the following rotational constants were obtained.
_??_
The carrier of the observed spectrum is the conformer in which the C-0 and N-0 bonds are trans to each other. Cis form was not identified in the present search. A least-squares fit of the observed rotational constants yields C-0= 1.436±0.004Å, N-0=1.424±0.004Å, O=:1.170± 0.004Å, ∠ CON= 114.5±0.6°and ∠ONO = 111.6±0.6° as the structural parameters when C-H = 1.097A, C-C = 1.5 28A, ∠HCC = 1 09.5°, and ∠CCO= 107.0° are assumed. The structure was compared with those of other X-ONO molecules, and a systematic change in the XON or ONO bond angle with X-group is found. The XON bond angle increases in the following order:
HONO<CH₃ONO<CH₃CH₂ONO<(CH₃)₃CONO
The order indicates that considerable steric effects exist between the alkyl group and the

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The adsorption equilibrium of phenol on the surface-modified and -unmodified activated carbons from its aqueous solutions was examined. An activated carbon, Pittsburg activated carbon (Calgon Co. ), was used as an adsorbent, and it was treated with nitric acid, hydrochloric hydrofluoric acid, air, oxygen, ozone, and also with hydrogen. The adsorption isotherms were found to conform with the Freundlich equation. The adsorption capacity decreased when oxidized carbon was used, while it increased when reduced carbon was used. The adsorption capacity of phenol on the activated carbon modified by various oxidants and reductants decreased in the following order: H₂>-H₂-unmodified>HCI-HF>O₃>O₂>unmodified>1N HNO₃>4N HNO₃>Air>13.2N HNO₃. It is concluded that the adsorption capacity changes in relation with the surface oxides of the activated carbon.

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Dehydrogenation of 2-butanol over various poly (metal phtalocyanine) catalyst (Poly-M-Pc)was studied by a continuous flow system under the atmospheric pressure. The yield of ethyl methyl keton (MEK) depended on the kind of the central metal in the catalyst. The order of catalytic activity was found to be as follows: Pt>Zn>Co≅Fe>Cu≅Ni. The mixed type catalysts, Poly-Zn-Ni-Pc, Poly-Zn-Fe-Pc, Poly-Zn-Cu-Pc and Poly-Zn-Co--Pc were more active in the yield of MEK than the single type catalyst such as Poly-Zn-Pc. Insertion of two species of metal ions to an enlarged conjugated catalyst system gave a good effect on the yield of MEK. the catalytic activity of Poly-Pt-Pc was higher than that of Pt(silica gel), that is, the Poly-Pt-Pc catalyst showed higher yield of MEK and lower activation energy than that of the Pt (silica gel) catalyst.

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Samples of TiO₂, SiO₂, TiO₂-SiO₂ were treated with aqueous solutions of HF in different concentrations. Their solid acidities were determined by amine titration, and catalytic activities for cumene cracking and for toluene disproportionation were examined by using a continuous flow reactor. The solid acidities of TiO₂ and TiO₂-SiO₂ were promoted most effectivebi by the treatment with 1.0 wt% HF aqueous solution. The highest catalytic activities for both: reactions were also obtained by the treatment with 1.0 wt% HF aqueous, solution (Table 2). The IR spectra of adsorbed pyridine showed that TiO₂, TiO₂-SiO₂ (9: 1); and TiO₂-SiO₂, (5: 5) had only Lewis acid sites. Brönsted acid sites, however, appeared after treatment with 1.0wt% HF aqueous solution. While the amount of weaker acid sites decreased, that of 8tronger: acid sites increased on surface fluorination of TiO₂-SiO₂.1

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Dehydration behavior and thermal stabilities of various 12-molybdophosphates were investigated by DTA, TG and X-ray diffraction methods. The dehydration of all compounds was completed below 300°C. In addition to the three known types of crystal structures of 12-molybdophosphates, i. e., the types with high-(I), medium- (II), and low- (III) water contents, X-ray diffraction studies of the dehydration process revealed the existence of a new low-water content type (X) and an amorphous type (A). Based on such structural information, the dehydration behavior was classified into the following three groups: Group 1 (salts of K⁺, Rb⁺. Cs⁺, T1⁺+, and NH₄⁺) which was prepared as type III and on heating lost its zeolitic w ater in one step (80∼90°C); Group 2 (salts of Li⁺, Na⁺, and Ag⁺) which was prepared as type I and underwent dehydration in two steps (90∼100°C and 150∼250°C) resulting in structural changes I→II→III; and Group 3 (acid and salts of multivalent cations) which underwent dehydration at two steps resulting in structural changes I→II→X→A. The thermal stabilities of 12-molybdophosphates at a high temperature were also dependent upon the counter cations. All bi- and tervalent metal salts were least stable, being decomposed at 400-450°C. The acid and NH₄⁺ salt decomposed at 420°C and 470°C, respectively, accompanied by intramolecular desorption of water and/or ammonia. Other univalent salts were stable up to their melting points (500∼700°C) which were well correlated with the radii of counter cations. The specific surface areas of 12-molybdophosphates were found to change with a temperature of heat treatment. The behavior also deeply depended upon the kinds of counter cations, corresponding to structural and thermal stabilities of respective salts.

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The catalytic activities of Fe₂O₃-K₂O-Al₂O₃ and Fe₂O₃-Al₂O₃ for NO-H₂ reaction have been investigated by the use of a conventional flow reactor at temperatures ranging from 300 to 570°C under the atmospheric pressure. The Fe₂O₃-K₂O-Al₂O₃ catalyst with a K₂O content near 3 wt% was more active than the Fe₂O₃-Al₂O₃ catalyst. In addition, in the case of the Fe₂O₃K₂O-Al₂O₃, catalyst, a simultaneous formation of NH₃ at high temperature higher than 400°C was very limited.
On the basis of the information obtained from a measurement of NO adsorption and the IR spectra of NO adsorbed on the catalysts, it has been speculated that a favorable effect of K₂O addition on the activity of the Fe₂O₃-Al₂O₃ catalyst is attributed to the increase in the adsorbed amount of NO, especially in more reactive species like NO^-.

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Quantum efficiencies (η_t) of photcelectrochemical reactions on various semiconductor electrodes determined by a temperature measurement were compared with those (η_a) obtained by the ordinary chemical actinometric method.
The semiconductors investigated a re as follows; n-type semiconductors (TiO₂, CdS, CdSe, ZnO, MoS₂, GaP and GaAs) and p-type ones (GaP and GaAs). In the case of the CdS single crystal photoanode η, was almost equal to η_a, but η_t of the n-MoS₂ photoanode, which had a lustrous surface, was larger than η_a. The major reason for the great difference in MoS₂, between η_t and η_a, is that the usual method of counting the number of photons by a chemical actinometry is to count all the photons irradiated on the surface of the electrode, including the reflected (or scattered) photon. While, by the temperature method, only the photons absorbed in the surface of the semiconductor can be counted. In order to check the influence of the reflected light on the quantum efficiencies, the reflectivities of the semiconductor electrodes were measured by the use of a chemical actinometer and a digital photometer. By considering the reflecting effect, η_a was corrected to be η_a'. Then η_a' was much closer to η_t in almost all the semiconductors.
It was found tha t by using the temperature method, intrinsic quantum efficiencies can be easily obtained even for the semicoductors which have great surface reflectance.

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Electrochemical behavior of glutathione (reduced form, GSH) on the mercury electrode has been studied in the buffer solution of pH 2.5 to 10. GSH yielded two pairs of cyclic voltammetric peak at low pH., From the relationship between peak currents and sweep rates and the dependence of peak current on GSH concentration, it was revealed that the more cathodic peak (Ep≈-0.4 V vs. SCE, pH 5.0) had the nature of adsorption peak and the more anodic peak (Ep≈-0.3 V vs. SCE, pH 5.0) had the nature of diffusion peak. pH dependence of t hese peak potentials suggests that they should have resulted from the thiol group. Some mercury compound was formed in this coulometric oxidation reaction, the concentration of which agreed with that calculated on the basis of the following equations;
_??_
The maximum cathodic peak currents of adsorption species in various p H were different from each other and their values decreased with increasing pH. This was attributed to the pH dependence of ionized forms of GSH. Then a maximum surface excess of adsorbed species at pH 5.0 was measured by double potential step chronocoulometry, and its value of 2.0×10^-10mol/cm2 came out. When increasing pH, there was another pair of peaks which appeared at a little more cathodic potential than the mercury dissolution potential. They are perhaps another pair of mercury relating peaks, judging from the result of coulometric oxidation at pH 9.0.

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The deposition of low temperature pyrolytic carbon (LTPC) on carbon fiber felt was studied using cis-1, 2-dichloroethylene as a source. When the carbon fiber felt was used as substrate, th e deposition rate, carbon yield, and carbon availability increased considerably, while by-pro-d ucts distinctly decreased in amount as compared with the case of graphite block substrate. A ccording to the preliminary experiments, the thermal gradient method was preferable over the isothermal method for the preparation of carbon fiber/LTPC composites with hi ensity. The standard conditions for the LTPC infiltration were as follows; maximguhm p ascukbinsgt- d rate temperature: 950°C, temperature gradient: 150°C/mm, source concentration: 13 vol%, gas fl ow rate: 460 ml/min. The deposition rate increased with rising temperature or increasing source supply rate. In spite of same supply rate, the different combinations of source concentration and gas flow rate resulted in the variations of carbpn yield, decomposition rate, and the distribution of packing rate of LTPC in the felt. From these results, it was concluded that the larger source concentration than that of standard conditions is favorable to increase the infiltration rate of LTPC, and the lower gas flow rate is preferable to increase the carbon yield. The essential situations which result in the above characteristic beha. viors4 o f LTPC infiltration are inferred as follows: (1) The carbon fiber felt substrate forms the three dimensional space made up of hot and broad surface. (2) The source concentration in the inner space of felt layer is probably less than that in the outside of felt. (3) The outside space volume of felt in which thermal decomposition of the source occurs is varied with the deposition conditions.

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X-Ray intensity has never been measured for as much as about 90% of the known radioactive nuclides. In order to measure X-ray intensity quickly for many nuclides, it was attempted to find relative-efficiency curves for Ge (Li) detectors of various sizes, where the objects of analysis with the curves were to be X-ray spectra (in literature) which had never been analyzed.
The γ-ray spectra were collected (from literature) which include both (1) full energy ' peak due to a γ-ray of known intensity and (2) full energy peak due to an X-ray of known intensity. The relative-efficiency curves have been obtained by trial-and-error method using the known intensities and “peak areas obtained from the collected spectra”. The curves are shown in Figs.4 and 5, where they correspond several sizes of detectors respectively. The uncertainty of X-ray-intensity value obtained by the application of the curves is at times smaller than the error involved in the known X-ray-intensity value. Therefore, the curves are useful as a complementary tool for obtaining X-ray intensities.

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OX-DTT (trans-1, 2-dithiane-4, 5-diol, a cyclic disulfide form of dithiothreitol) gave two cathodic waves at DME in the buffer solution of pH 2 to 12. The first wave (E_1/2=-0.430V vs. SCE, at pH 4.5) had a nature of reaction-controlled current and the second wave (E_1/2=-0.91V vs. SCE, pH 4.5 ) showed a nature of diffusion-controlled current. In AC p olarography, a single AC wave of irreversible nature was observed at E_??_.0.460 V, pH 4.5. The polarographic behavior of OX-DTT was interpreted as follows. The first DC polarographic wave height is controlled by the rate of adsorption of OX-DTT to the DME surface (eq. ( 4 )) and the adsorbed OX-DTT is irreversibly reduced to dithiothreitol (DTT) as shown in eq. ( 6 ). The second DC wave is due to the irreversible reduction of OX-DTT to DTT (eq. ( 8 ) ) at DME., Cyclic voltammetric behavior of OX-DTT at HMDE was also interpreted in terms of eq. ( 4 ), ( 6 ) and ( 8 ). Current oscillation phenomenon observed at mercury electrode when the voltage scan rate is very slow (less than 10 mV/s) seems due to a complicated oxidation and reduction process associated with the adsorption of OX-DTT, DTT and mercury salt of DTT.

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The adsorption behaviors of arsenic(Ill) ion in water on ten kinds of ion exchange resins which were loaded with iron(D1) and zirconium (N) were investigated by the batch and the column methods. The ion exchange resins investigated in this study were Diaion WK 10, WK 11, WK 20, Amberlite IRC 50, Fumiace, Dowex A 1, Diaion CR 10, CR 11, CR 12and Uniselec UR 40, as shown in Table 1. The relation between the concentrations of arsenic (III) ion in the adsorbent Q, and in the aqueous phase C, after equilibration of amm onium buffered solution, followed the Freundlich's law of Q=KC^1/n.
By using two constants, 1/n and K, the adsorptio n of arsenic(III) ion for each adsorbents was estimated. It had become apparent that the weak acid cation exchange resin as matrix substance and zirconium(IV) as metal ion gave better adsorbent characteristics for the arsenic (III) adsorption than chelating resin and iron(III) ion, respectively. It was also found th at an excellent adsorbent had relatively high metal content but an adsorbent having higher metal loading did not offer necessarily a good adsorptivity. The breakthrough curves were made by using the column packed with 5 ml of each adsorbents and flowing the waste water drained from a geothermal power plant. Relatively large column adsorption capacity was obtained when the adsorbent of a relatively small constant, 1/n, was used. However such an adsorbent did not necessarily gave a large column capacity.

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Surface ionization mass spectrometry has been developed to measure isotopic abundances and concentrations of silver in commercial high-purity metals, environmental materials such as rocks and plants, and ¹⁰⁹Ag and ¹⁰⁷Ag spikes. A minute amount of silver is extracted into a dithizone chloroform solution from a nitric acid solution of above samples. After the silver is back-extracted into 6.0 ml of a 7 mol/l HNO₃ solution, the solution is evaporated to dryness under the nitrogen atmosphere. Silver nitrate thus formed is dissolved in a mixture of 60 μl of an 0.003% silica gel suspended water and 5μl of a 2% phosphoric acid. An aliquot of this solution is applied to the mass spectrometry using a rhenium single filament as an ion emitter. The proposed method can detect the presence of 10^-14 g of silver on the ion emitter, and measure the ¹⁰⁹Ag/¹⁰⁷Ag isotopic ratio in environmental materials with the accuracy of 0.1∼0.2% in the coefficient of variation. Isotope dilution mass spectrometry using a ¹⁰⁷Ag spike has revealed the silver concentration in the environmental standard materials, which were prepared by the National Bureau of Standards, U. S. A. and National Institute of Environmental Studies of Japan, as follows; 27.9±0.2 ppb for the Orchard Leaves and 34.3+0.3 ppb in the Pepper Bush. The determined values of silver in the Granodiorite, JG-1, and Basalt, JB-1 powders made by the Geological Survey of Japan are 25.4±0.4 ppb and 41.3±0.1 ppb, respectively. Silver concentration in a coastal sea water sample is found to be at the level of 2.5±0.4 ppt.

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The reaction of diphosphorus tetraiodide with carboxamides has been investigated in carbon tetrachloride in the presence of tertiary amines. Both aliphatic and aromatic carboxam ides underwent mild dehydration to give the corresponding nitriles in moderate to good yields. The reaction was clean and no tarry product was formed. Without amine bases the conversion to nitriles was quite slow and incomplete. Replacement of carbon tetrachloride by other solvents such as benzene, acetonitrile, and diethyl ether led to significant decreases in the yields of nitriles even in the presence of amine bases.

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Novel zwitter ion compounds (ZC), which have guarternary ammonium and monoalkyl sulfite ions, were synthesized by the equimolar reaction among epoxide, sulfur dioxide and tertiary amines. In this reaction, the competitive formation of five-rwnbered cyclic sulfites (SU) was observed. When trimethylamine was used as an amine component, ZC was alone obtained. When other tertiary amines were used, however, both ZC and SU were obtained. The molar ratio of SU to ZC increased with increasing steric hinderance of the substituents for amines, and depended on neither pKa of amines nor structure of epoxides.

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The reaction between benzoic acid and, phenyl glycidyl ether (PGE) has been studied using a Lewis base such as amines, phosphines, sulfides etc. as catalyst. No relation was found between the basicity of these Lewis bases and their catalytic activity. The catalytic activity of more basic triethylamine, for example, was lower than less basic friphenyiphosphine.
In the reaction of benzoic acid and PGE in the presence of a Lewi s base, the Lewis base, at first, reacts with PGE to form the corresponding onium salt, which then accelerates the reaction of benzoic acid and PGE. The formation of the onium salt in the reaction system is related not only to the nucleophilicity of the Lewis base but also its basicity. Triphenylphosphine, which has weak basicity and strong nucleophilicityshows a remarkable catlytic activity. The stability of the onium salt formed in the reaction system may also be associated with the catalytic activity.

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In order to reexamine the U-shaped Hammett plots reported in the preceding papers, the reactions of benzenesulfinic acid with aryl acrylates which are simpler α, β-unsaturated car. bonyl compounds than N-substituted maleimides have been conducted. A similar Hammett plot was obtained with respect to the substituents of aryl acrylates.
By using substituted benzenesulfinic acids which have a linear substituent effect on the reacting sulfur atom, the reaction mechanism has been deduced by way of the substituent effect on the reaction rate of phenyl acrylate with substituted benzenesulfinic acids. The linear relationship of Hammett plot was found for the substituents of substituted benzenesulfinic acids. As shown in Table 1 and Scheme 1, the nucleophilic addition of sulfinic acid appears to take place at the β-carbon of the acrylate, thus forming sulfone. As noted in Tables 4and 5, all the activation entropies have large negative values. The result indicates that a charged intermediate is stabilized by thern medium. It can therefore be presumed that the degree of freedom of the transition state is smaller than that of the initial state, and that the intermediate is cyclic. It is concluded that the reaction of substituted benzenesulfinic acid with aryl acrylate proceeds with the ionic process, and that the nucleophilic attack of the sulfur atom of sulfinic acid on the β-carbon of the vinyl group of the acrylate is a ratedetermining step.

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Photochemical reaction of an unsymmetrical diolefln, dimethyl ester of 4- (2-carboxyvinyl)α-cyanocinnamic acid (CVCCMe₂) has been investigated. CVCCMe₂ was prepared in good yield by condensation of methyl p-formylcinnamate with methyl cyanoacetate. CVCCMe₂ crystals were highly photoreactive and on irradiation gave the amorphous oligomer having the head to head type cyclobutane ring in the main chain. The photochemical behavior and crystal structure of CVCCMe₂ are the same as those of dimethyl m-phenylenediacrylate and they belong to the same type of photoreactive crystals. The thin film composed of CVCCMe₂ crys-t als, 1, 2-benzanthraquinone as a sensitizer and poly (methyl methacrylate) showed high image resolution and proved to be useful as photosensitive materials.

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2, 3, 5-Trichloro-[1], 2, 3, 6-trichloro-[2]3, 2, 3, 5, 6-tetrachloro-[3], 2, 3, 5, 7-tetrachloro-[4]and 2, 3, 5, 6, 8-pentachloro-1, 4-naphthoquinones [5], which were synthesized from 5-amino-[14] and 6-amino-2, 3-dichloro-1, 4-naphthoquinones [15], were condensed with aniline in ethanol. The expected two isomers from each reaction were isolated and their structures were determined by the transformation to the known compounds. Effects of the chloro substituent on the benzenoid ring on the reactivity at the 2- and 3-positions have been disclosed by comparing the isomer ratios. The reaction of 6-amino-2, 3, 5, 7-tetrachloro-1, 4-naphthoquinone [21] with aniline was also investigated, and the effects of the amino group and chlorine substituents on the above mentioned reactivity are discussed.

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The equilibrium constants fo the decomposition of methylheptadecanes-urea and methylnonadecanesurea adducts have been determined in toluene at 0, 10 and 20°C to compare the strength of adduct formation - with that of normal alkane-urea adducts. The changes in enthalpy of the urea adduct formation of the methylalkanes were evaluated from the temperature dependence of the equilibrium. constants. Equilibrium constants for the decomposition of methylheptadecanes-urea and methylnonadecanes-urea adducts were in. the range 3×10^-4∼8×10^-2 and 1×10^-4∼2×10^-2, respectively. Thus the values of methylalkanes-urea adducts wer e larger than those of normal alkanes of the same carbon number in straight carbon chain by a factor of 10 to 10³. The enthalpy change clue to the methylalkanes-urea adduct formation also differed from one another and was smaller than those of normal alkanes of the same carbon number in straight carbon chain by 2 to 11 kcal/mol. The presence and the position of the side methyl group in guest molecules were concluded to influence the stabilities of the urea adducts to a large extent. A new model related to the configurations of guest me thylalkanes in the host urea channel or the interactions between guest methylalkanes and host urea was presented.

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Whereas the coupling reaction of 1-naphthol with p-substituted benzenediazonium salts occurs mainly at the 4-position of 1-naphthol, 1-diazonio-2-naphthol-4-sulfonate reacts with 1-naphthol preferentially at the 2-position, giving 2-azo dyestuff which is particularly important as acid mordant dyes. In order to disclose the mechanism for the regioselectivity of the coupling reaction, kinetic studies have been carried out at 25°C under constant ionic strength (0.5). The coupling takes place exclusively at 2-position of 1-naphthol to give 2-azo dyestuff. Logarithm of the apparent second order rate constant correlates linearly to the pH value with the gradient of O.5 at pH<10.1, and O5. at pH>10.1. The active species are concluded to be 1-naphtholate ion [Nap-] and 1-diazonio-4-sulfonato-2-naphthola. te ion [DSN-]. Acid catalysis by free 1-naphthol [NapH] is also found operative. The reaction rate, ν, is expressed as follorwes, Where k_NaPH, k_o denote the catalytic constant of [NapH] and the solvent constant, respectively.

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Binding of Methyl, Ethyl and Butyl Oranges (MO, EO and BO) to poly (N-butyl-4-vinylpyridinium bromide) (C₄P 4 VP) (Degree of Quaternization, DQ= 100%) has been studied at 25°C by means of the dynamic dialysis technique and spectrophotometry. The binding isotherms for MO, EO and BO-C₄P 4 VP in an acetate buffer solution at pH 5.7 show the high binding affinities with the binding densities close to 1 over ten fold variation of the dye concentrations (Figs.2, 3 and 4). In terms of the theory of Bradley et al., the change of absorption spectra of MO, EO and BO-C₄P 4 VP (Figs.6, 8 and 9) reveals that the stacking coefficient q, which represents the interaction between -neighbouring dyes bound to polymer sites, increases in the order, MO<EO<B0 (Table 1).

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Preparation of molecular sieving, carbon derived from Saran waste was studied. Saran waste was decomposed and carbonized at 800°C. Then, the resulting Saran char was granulated into sphere, whose diameter being 0, 7 mm, by the addition of 4.4∼26.1 w, t% of coal tar pitch and 13.0 wt% of sulfite pulp waste liquor. The granular pellets thus obtained were heat-trea ted at 800°C. The carbon derived from Saran waste did not adsorb neopentane, whose molecular diameter being 6.2Å, and when 12.6, 14.4 or 17.0 wt% of coal tar pitch was added to it, it showed excellent molecular sieving property to separate butane (4.3Å) and isobutane (5.0Å)(Fig.7). This indicates that the pore size of it is similar to that of Zeolite 5 A (Fig.7 and Table 4).

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Formation of composite cationic reverse osmosis membrane was investigated by the amination and crosslinking of vinylbenzyl chloride-styrene copolymer with various N, N, N', N'tetramethyl-α, ω-alkane diamines. The composite membrane was formed by casting the polymer solution in a thin film on a porous polypropylene supporter, evaporating the solvent, and finally heat-curing it. The amination with N, N, N', N'-tetramethy1-1, 6-hexanediamine was superior to other tertiary diamines in preparation of membrane with good reverse osmosis performance. The proper equivalent quantity of diamine was more than that of benzyl chloride by a factor of 3∼4. The membrane had a water flux of 10l/m2⋅h at a salt rejection level of 99.3% with 5000 ppm NaC1 solution under 80 kg/cm2. Membrane performance varied with composition and molecular weight of a copolymer. Water flux of membrane decreased with increasing styrene in a copolymer, but the membrane derived from (1-1) copolymer showed the highest salt rejection. The rejection of membrane for NaOH was the same as that for NaCl. This charged membrane is markedly resistive to acids and bases and useful at a wide pH range.

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The performance and the adsorption site of Cu ( II ) -exchanged Y-type Zeolite (Cu ( II ) -NaY)for the adsorptive removal of NH₃ at low concentration level have been investigated in the presence of H₂O or H₂O-H₂S mixture. The experiments were carried out by using a packed bed flow apparatus and a thermobalance under an atmospheric pressure at 50∼200°C. For the adsorption, the inlet gas was a mixture of NH₃ (0∼240 ppm, O.1, 1%), H₂S (0∼300 ppm), H₂O(3.9∼11.6%), and N₂, and the total gas flow rate was 500 and 1000 N cm'imin for 1.0 and 1.85ml of the adsorbent with average diameter of 0.4∼1.0 mm. For the desorption or reg eneration, the inlet gas was pure N2, the total flow rate was the same as above, and the rate of temperature rise was 2.5°C/min. In this way, the break-through curve and the temperatureprogramed desorption curve were measured.
The following results were obtained: 1) Cu (II)-NaY is a good adsorbent for NH₃ at low concentration level below 20 ppm in the presence of water vapor, and the adsorption of NH₃on solid acid sites of Cu0H+ and H+ becomes predominant.2) Under the coexistence of H₂S and water vapor, solid acid sites Cu0H+ are changed by reaction with H₂S, but acid sites formed (CuSH+, H+) act effectively as the adsorption site for NH₃.

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Sodium dodecylbenzenesulfonate (DBS) is extracted by ethyl acetate from acidic solution whose pH being 1. The proposed extraction method was applied to the concentration and purification of micro amounts of anionic active surfactants contained in river or sea water. The procedure is as follows: A 2 ml of 12 N surfuric acid was added to 100 ml of sample water, and then anionic active surfactants such as DBS were extracted by shaking it twice with 20 ml and 10 ml of ethyl acetate for 20 min. The two organic phases were put together and evaporated on a water bath.
The residue was d issolved in 20 ml of buffer solution whose pH being 4-5, and the resulted solution was washed with 10 ml chloroform by shaking it for 10 min. After separating the chloroform layer, the layer was washed with 10 ml of buffer solution whose pH being 4∼5 to back-extract the DBS which was partially extracted into the organic phase. After discarding the organic phase, anionic active surfactants in the aqueous phase was determined by the Methylene Blue method. Washing by chloroform whose pH being 4∼5 was very effective to expel Methylene Blue active substances except anionic active surfactants like DBS.
Through the proposed procedure, the recovery of DBS was 95∼101%. The proposed method is more simple and more rapid procedure for the concentration of anionic active surfactants than other methods, such as ion-exchange concentration method, etc. and can determine specifically the anionic active surfactants like DBS.

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Trace analyses of terpenoids compounds in the sediment by silica gel column chromatography and followed by mass fragmentgraphy were studid. A continuous extraction of the sediment samples for 6 h was appropreate. Terpenoids (longiforene, calamenene, dehydroabietane, dehydroabietin, 1, 2, 3, 4-tetrahydroretene and retene) were eluted in a fraction of hexane. For the determination of nano grams of terpenoids by mass-fragmentgraphy, a column of 5% SE-30 was used. This method is applicable to the determination of trace amounts of dehydroabietane and retene in the sediment in Hiro Bay.

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1, 3-Dioxolane derivatives were prepared by simple reaction of epoxides with carbonyl compounds using AlCl₃ catalyst. Carbonyl compounds included cyclohexanone, benzaldehyde, isobutyl methyl ketone, 2-octanone and acetophenone. Two kinds of epoxides, e., chloromethyland ethyloxiranes, were used in the synthesis. The reaction was carried out without solvent or in carbon tetrachloride at 40∼80°C for 5 h. Yields of 1, 3-dioxolanes ranged from 36 to 88% depending on competitive polymerization. Products from the reaction of unsymmetrical carbonyl compounds and epoxides were the mixture of stereoisomers.

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Hyperfine coupling constants (a_N) of aryl benzhydryl nitroxides increase with electronegative substituents on the N-phenyl ring. The Hammett plot of a_N against σ gave p= 1.0 (γ=0.97). However a_β-H values of the nitroxides are independentof the substituents. Benzhyd ryl phenyl nitroxide was found to adsorb oxygen reversiblely depending on oxygen pressure.

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Based on the Cava's procedure, a series of the title compounds has been prepared and their properties recorded. All the compounds obtained are photo- and thermolabile crystalli ne solids, which readily decompose on storage. Electron-releasing groups on the arom atic ring tend to enhance the relative stability of benzyl tellurocyanates and lower that of dibenz yl ditellurides, whereas the reverse trends hold with electron-withdrawing groups.

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