The molar fraction solubilities of radon _χ1 to 1, 2-dimethylbenzene, 1, 3-dimethylbenzene, 1, 4dimethylbenzene, 1, 3, 5-trimethylbenzene, 1, 2, 4-trimethylbenzene and 1-isopropyl-4-methylbenzene were determined. A radon solution was put in a closed vessel with air phase. Radon contents in the initial solution and the solution in which gas-liquid equilibrium had achieved, were measured by liquid scintillation counting. Radon content in the gas phase was obtained from the difference of the radon contents in the two solutions. Radon solubility was resulted from the ratio of liquid phase concentration to the gas phase concentration. The solubility formulas as a function of temperature were presented as follows in the range of 290-301 K.
1, 2-Dimethylbenzene:_χ1=exp (1575.5/T-8.219),
1, 3-Dimethylbenzene:_χ1=exp (1638.4/ T8.389),
1, 4-, Dimethylbenzene:_χ1= exp (1627.1/ T8.287),
1, 3, 5-Trimethylbenzene:_χ1= exp (1599.1/T-8.218),
1, 2, 4-Trimethylbenzene:_χ1= exp (2342.2/ T1 0.717),
1-Isopropyl-4-methylbenzene:_χ1=exp (2310.6/ T1 0.412).

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In order to confine hydrogen in hydrogen storage alloys, a new method, i. e. immersion of the alloy into a solution consisting of some kind of oxidants, was examined. Strong confining effect of hydrogen was observed by the immersion of the alloy in the solution containing chromate ion even after the alloy was kept under the atmosphere for more than 5000 hours.
It was shown from results of XPS and AES tha t nickel particles on the alloy surface which act as active sites for hydrogen absorption/desorption were changed into nickel oxide by the confining treatment, and the oxide remained to be stable by residual chromate ion on the alloy surface. By formation of the nickel oxide, i. e., vanishment of surface active sites, it is presumed that hydrogen was confined in the hydrogen storage alloy after the treatment.
In the case of Ni-MH batteries, rem aining capacity of negative electrodes agree well with the capacity evaluated from the amounts of hydrogen in the hydrogen storage alloys (active material for negative electrode) after the treatment.

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Surface acid properties of alumina solid Lewis superacid-supported platinum catalyst (Pt/AmLSA)were measured by FT-IR spectrometer using pyridine and hydrogen as probe molecules. Preparation of the catalyst was as follows: Pt was supported on A mLSA, p repared by high-temperature chlorination of ii-alumina, by sublimation of PtCl₂ at 773 K followed by hydrogen reduction above 673 K. O n the AmL SA original hydroxy groups dissapeared. On the Pt/AmLSA hydroxy groups appeared again after hydrogen reduction treatment and hydroxy groups came out when adsorbed pyridine was outgas sed above 493 K. These hydroxy groups had no Bronsted acidity. However, below 583 K the a dsorption peak at 1540-1543cm^-1 due to pyridinium ion was always present on the Pt/AmLSA and pyridine-H_5-xD_x molecules were formed if deuterium was used. Furthermore, the pyridine molecules coordinated with strong Lewis acid sites were converted to piperidine in t he presence of gaseous hydrogen at 473 K. These results indicate that hydrogen atoms remain on the Pt/AmLSA after the reduction of PtCl₂; a part of the hydrogen atoms form pyridinium ion, and another part causes hydrogen exchange reaction o f the pyridine coordinated to the strong Lewis acid site. Such phenomena are concluded to be so-called “hydroge n spillover”, which are observed only on the Pt/AmLSA.

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Magnesium potassium titanates, K_0.8Mg_0.4Ti_1.6O₄ and K₂MgTi₇O₁₆, whose oxygen-site was partially substituted by fluorine, with anisotropic particle forms were synthesized via KDC (Kneading-DryingCalcination) process. Those synthesis temperatures (1000°C) fell by 200°C by use of MgF₂ as a reactant.
The former consisted of platy particles ca.50μm long and 5μm thickness. Its hydrated compound showed adsorption ability of ammonium ion by 2.2 mmol/g. The latter consisted of rod-like particles with ca.10μm length and 5 pm diameter.

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In order to examine the possibility of caffeine as an extractant, the extraction of metal ions from acidic chloride media was studied at 298 K using the mixture solvent of chloroform and 2-ethyl-1-hexanol. Caffeine has exhibited a high selectivity for palladium(II) over base metals such as copper (II), nickel (II), and iron (III), and over precious metal such as platinum (IV). The stoichiometric relation in the extraction of palladium (II) with caffeine was elucidated by examining the effects of chloride ion, hydrogen. ion, and caffeine concentrations on its extractability. In addition, palladium (II) was found to be extracted selectively with caffeine from the mixture containing a 25-fold amount of platinum (IV) or copper (II). The stripping of palladium (II) was performed to an extent of 80% by a single batchwise treatment with an aqueous mixture solution of hydrochloric acid and thiourea.

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Iminophosphoranes and iminoarsoranes are isoelectronic compounds of ylides. It is expected that they can perform the Stevens rearrangement as observed for the ylides. In order to investigate the mechanism of this rearrangement, theoretical calculations of mono-substituted iminophosphoranes and iminoarsoranes with the Mφller-Plesset perturbation theory up to the fourth order were performed for the rearrangement reactions of ZH₂MNH→H₂MNHZ (Z = H, CH₃, CH =CH₂, SiH₃ and GeH₃: M=P and As). The migrations of hydrogen atom, methyl, and vinyl groups were antarafacial with large activation energies as readily expected based on the Woodward-Hoffmann rule. On the contrary, the rearrangement of the silyl group along with that of the germyl group displayed that it was a suprafacial process with a small activation energy. Structural and molecular orbital considerations in the transition states clearly demonstrated that the hypervalency of the Si and Ge atoms lead to the suprafacial migration with the small activation energies. While the migrations of hydrogen atom, methyl, and vinyl groups of iminophosphorane required an activation energy about 20 kcal/mol higher than those of the corresponding ylide compounds, the activation energies for the rearrangement of the silyl and germyl groups were comparable. The origin of this behavior is discussed based on the difference of the M-Z bond energies between ylide and iminophosphorane as well as their structural features.

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We synthesized a novel cyclic formal, 1, 3, 5, 7, 10, 13-hexaoxacyclopentadecane (HOCP), which is a direct reaction product of 1 mol of trioxane and 3 mol of ethylene oxide. The novel cyclic compound was separated and collected using a micro-distillation apparatus and gas chromatographic method. The chemical structure was determined using ¹H-NMR, ¹³C-NMR, mass spectrum and elemental analyses. Formation of HOCP was critical. When the mole ratio of ethylene oxide to trioxane was below 0.026, only 1, 3, 5, 7-tetraoxacyclononane (TOCN), which was the reaction product of 1 mol of trioxane and 1mol of ethylene oxide was formed. When the mole ratio of ethylene oxide to trioxane was around 0.033, 1, 3, 5, 7, 10-pentaoxacyclododecane (POCD), which was the reaction product of 1 mol of trioxane and 2mol of ethylene oxide was formed additionally to TOCN. When the mole ratio of ethylene oxide to trioxane was around 0.039, HOCP was formed additionally to TOCN and POCD. In the commercial base acetal copolymer which was produced by the copolymerization of trioxane and ethylene oxide, it is known that there is a consecutive three-unit sequences of ethylene oxide, and this consecutive sequences might be postulated to come from the ring-opening polymerization of the novel cyclic formal of HOCP. Direct reaction between trioxane and ethylene oxide is thought to supply us a posssibility of a new type and new route of crown ether.

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This study discusses the capacity of sorption of various ions in calcium silicate hydrates. Chlorideion, sulfate-ion and phosphate-ion were sorbed in synthesized calcium silicate hydrates (C-S-H). The amount of sorbed chloride-ion, sulfate-ion and phosphate-ion in C-S-H were 172 mg/g, 54 mg/g and 667 mg/g, respectively. In the case of sorption of phosphate-ion, phosphate-ion and C-S-H reacted to produce hydroxyapatite. In the leaching test, 15% of chloride-ion, 18% of sulfate-ion and 34% of phosphateion were dissolved from C-S-H sorbing respectiveanions. On the other hand, 65% offixed chlorideion in Friedel's salt was dissolved in the leaching test. Therefore, the fixing ability of chloride-ion in C-S-H is higher than that in Friedel's salt.

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When a mixture of 4 -biphenyly1b enzoate (1) and anhydrous aluminum chloride ( AlCl₃w) as boiled in o-dichlorobenzene, 4-hydroxy-3-biphenylyl phenyl ketone (3) was obtained as a main product together with a small amount of 4'-hydroxy-4-biphenylyl phenyl ketone (4). A rearrangement product 4-hydroxy-3-biphenylyl methyl ketone (5) was given in the reaction of 4 -biphenylyl acetate (2) with AlCl₃ under the same reaction conditions. Corresponding amounts of 4-biphenylol were obtained as a by-product in the Fries rearrangement of 1 and 2 under the reaction conditions. In these reactions, the reaction of 2 seems to proceed faster than 1. Products distributions (rearrangement products, 3 and 5, and 4-biphenylol) in the Fries rearrangement of 1 and 2 were remarkably different depending upon the reaction temperature. On the other hand, a small amount of 1 and 3 was detected in the reaction of 4with AlCl₃F. ries rearrangement of 1 and 2 may proceed predominantly via an intramolecular pathway.

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The samples collected in Yonezawa from April 1993 to March 1997 on an event basis were analyzed for pH, electric conductivity (EC) and concentrations of major ions (Na⁺, K⁺, NH₄⁺, Ca²⁺, Mg²⁺, Cl^-, NO₃^- and SO₄^2-). These data were compared with the interim monitoring reports from Acid Deposit ion Survey of Japan Environment Agency Phase III. The results of the annual data observed in Yonezawa were as follows: (1) When the annual means of electric conductivity (EC) values were higher, the ones of pH values were lower. (2) Both Na⁺ and Cl^- concentrations in winter were higher about 25 times than the ones in summer, and the EC values were about three times. (3) It was found that the atmosphere in Yonezawa has become worse gradually after 1993, and that the pattern of pAi-pH in Yonezawa was made identification of the one in other areas of Japan.

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