A plant leaf responded markedly to CO₂ stress by changing its cellular potential. Moreover its response patterns were modified by the coexistence of small amount of odor compounds, which suggested the presence of excellent sensing function of a plant leaf for odor compounds.
In this study, I have analyzed the CO₂ stress response electrochemical ly with multi-microelectrode system. At first, I have clarified that epidermal cells of Tradescantia virginiana L. within a radius of about 2 mm are electrically short-circuited. Electrochemically, however, they have been found isolated from each other. Based on the electron microscopic analysis and the dye diffusion experiment, I constructed a leaf structure model. Intracellular responses corresponded to the vacuolar potential change. Since the potential change could not be elucidated without taking the electrogenic potential into account, I proved the existence of H⁺-ATPase in the vacuolar membrane of T. virginiana which can generate the electrogenic potential. As the result, the mechanism of CO₂ stress response was explained by the diffusion potential of K⁺ and H⁺, and the electrogenic potential of H⁺.

View full abstract

Potentiometric titration method was applied to judge whether precipitated hydroxide is a complex hydroxide or a mixture when alkali solution was added to an aqueous solution containing two kinds of metal salts (Al³⁺, Fe³⁺, Ni²⁺, Zn²⁺, Cu²⁺). Capability of complex formation between the metal hydroxides was investigated by comparing the pH of the plateau in the titration curves with that for the solution of one kind of metal ion. Complex was formed for all of the combination between divalent ion and trivalent ions, and the sequence of the capability was Ni²⁺ > Zn²⁺ > Cu²⁺, In the case of divalentdivalent systems, complex was formed in the solution of Ni( NO₃)₂ -Zn(NO₃)₂, but Cu(NO₃)₂ -Zn(NO₃)₂and Cu(NO₃)₂-Ni(NO₃)₂ systems formed only mixtures.

View full abstract

Chemical species in aqueous solutions of rhodium (III) nitrate and chloride were characterized by UV-VIS spectrometry and the adsorption of rhodium complexes on γ -alumina in acidic solutions was studied.
The UV-VIS absorption spectra confirmed that a cationic complex, [Rh(H₂O)₆]³⁺ exists in the commercially available “ rhodium nitrate solution ”. The hexaaqua complex was not found in the aqueous solution of Rh(NO₃)₃⋅ 2H₂O and only a strong absorption spectrum was observed in the UV region.
In the aqueous solution of rhodium chloride, a neutral complex, [RhCl₃(H₂O)₃ ] was found and this complex was accompanied by a small amount of hydroxo complexes.
It was shown that the hexaaqua complex can not adsorb on γ -alumina at room temperature under strong acidic condition as pH < 1, but the uptake of Rh by alumina occurrs during high temperature impregnation with increasing dissolution of alumina.
The hydroxo complex [Rh(OH)(H₂O)₅]²⁺ seems to react with the alumina surface by ligand exchange reaction.
The uptakes of the neutral and anionic complexes by alumina from the rhodium (III) chloride solution were also presumed to proceed by the ligand exchange reaction mechanism, because the addition of chloride ion to the impregnating solution showed no inhibition effect on the adsorption of the rhodium (III)complexes.

View full abstract

Silica alumina gels with various compositions were prepared by cogelation using instantaneous mixing of aqueous solutions of sodium silicate and aluminium nitrate, followed by washing, drying at 30° C for 24 h and calcining at 500° C for 2 h. The washing is composed of the two processes: the first is dispersion of the hydrogel into ion-exchanged water, and the second is separation by filtration of the dispersing element. The hydrogels and filtrates were sampled the whole quantity in every washing through five times. The amounts of elution of Na, Si and Al ions from the cogels into their filtrates were examined through the repetitive washing process. The chemical compositions of each gel and each filtrate obtained were determined by chemical analysis and ICPE spectroscopy. In order to know the effect on the surface composition by the calcination, one of the cogels was calcined at the temperatures up to 500° C, and the alumina content of these samples was examined by XRF analysis.
As the results, the decrease of Na ion content in these hydro-cogels due to repetition of washing could be recognized. Further, the elution of Si was found to be more than that of Al for all the cogels, and the elution occurs on the surface of primary particles of the co-gels. It was known that the calcination enhances the surface alumina composition. The comparison of the alumina content of the cogels known by chemical analysis with that known by XRF analysis showed that the former is the same as the stoichiometrical composition, and the latter is larger than that.
We concluded that the surface Al₂O₃ composition of primary particles had become markedly higher than the bulk composition through washing and calcining the hydrogels.

View full abstract

Cadmium contents of 55 Permian dolostone samples collected from 6 localities in Japan were determined by flame atomic absorption spectrometry combined with ammonium pyrrolidinedithiocarbamate (APDC) -4-methyl-2-pentanone solvent extraction system. Positive correl ations exist among the Cd, Zn, Mn, Ni, and Cu contents of these samples, suggesting the similar geochemical behavior of these metals during the formation of dolostones. More Zn, Mn, Ni, and Cu are incorporated in dolostones than in limestones because of the similarity of ionic radius between these metal ions and Mg²⁺. No enrichment of Cd has however been observed in dolostones, probably due to large difference in ionic radius between Cd²⁺ and Mg²⁺. The geometric mean of Cd in Permian dolostone samples (n=81) including Kuzuu ones (n=26) was 0.43 ppm, which was almost the same as that (0.47 ppm) of Permian limestone samples (n=56) collected from the same localities. These values are somewhat high as compared with the geometric mean of Cd (0.07 ppm) of Quaternary limestone samples (n=94) taken from the Nansei Islands, southwestern Japan. These values are also higher than the abundance (0.09 ppm) of Cd in carbonate rocks compiled by Mason and Moore, suggesting the peculiarity of Cd contents of Permian carbonate rocks in Japan.

View full abstract

The adsorption and the separation of some o-, m- and p-isomers of nitrobenzene derivatives by thinlayer chromatography (TLC) have been studied. From the viewpoint of effective utilization of natural sedimentary zeolite, clinoptilolite produced in Futatsui, Akita Prefecture, was used as an adsorb ent of thin-layer component.
In addtion, zeolite feature as solid acid was characterized by IR and micro-calorimetry of a mmonia adsorption to reveal the behavior to adsorption on thin-layer.
Clinoptilolite was f ound to b e effectively used as well as alumina and silica gel as an adsorbent in TLC. As shown in the example of the separation of p-nitroaniline on clinoptilolite chemically treated with hydrochloric acid, the adsorption due to a kind of molecular shape selective function was considered. Moreover, natural clinoptilolite has high mechanical strength, and therefore, the present result suggests that it can be utilized as separation and adsorption materials for aromatic nitro-compounds from aqueous solution when the Si/Al ratio and the hydrophobic property can be controlled.

View full abstract

The [2+2]cycloaddition of 2, 3-dihydrofuran (1) to phenyl isocyanate (2a) at 100° C for 20 h gave bicyclic β -lactam, 7-phenyl-2-oxa-7-azabicyclo[3.2.0]heptan-6-one (3a) with 86% yield. The reaction gave a good result when the reaction was carried out in the absence of catalyst in nonpolar solvent. The [2+2]cycloaddition of 1 to various aryl isocyanates at 100° C for 20 h gave corresponding bicyclic β -lactams in high yield and selectivity, however, the reactions of 1 with alkyl isocyanates and of other vinyl ethers with 2a did not occur. A concerted mechanism was supposed on the [2+2]cycloaddition of 1 to 2a.

View full abstract

Heating of 3-(2-alkoxyphenyl) -3- (4-diethylamino-2-hydroxyphenyl) -1(3H) -isobenzofuranone or 3- (4-diethylamino-2-alkoxyphenyl) -3- (2-hydroxyphenyl) -1(3H) -isobenzofuranone derivatives (1) under acidic and/or basic media provided fiuoran dyes (2), which have been widely used in pressure or heat sensitive recording system as color forming materials, in high yields. Mechanistic studies using oxygen-18 labeled model compounds as tracers and kinetic measurements of this intramolecular cyclization process revealed that the hydroxyl group in the phenol moiety of 1 attacked the ipso-carbon atom bearing the alkoxyl group via nuclephilic aromatic substitution reaction. Furthermore, in case of 3- (2alkoxy-5-anilinophenyl) substituted isobenzofuranone derivatives, the participation of free-radical pathway was assumed in their ring closure reactions.

View full abstract

o-Methylanisole was converted to 2-methyl-6- (4-methoxy-3methylphenyl) -2heptanol (1) via 4(4-methoxy-3-methylphenyl) pentanoic acid (4). The treatment of the monocyclic tertiary alcohol (1)with p-toluenesulfonic acid in refluxing toluene afforded a mixture of bicyclic compounds, 6-methoxyisocalamenene (11), 7-methoxycalamenene (12), 1-isopropy1-6-methoxy-4, 5-dimethyl-1, 2, 3, 4tetrahydronaphthalene (13), 6-methoxydaucalene (14) and 7-methoxycadalene (15), along with a deoxy compound, 2methyl-6- (4-methoxy-3-methylphenyl) heptane (16). Among the products, 11and 14 were new compounds. In order to iden tify the structures of the new sesquiterpenes (11) adn (14), these compounds were synthesized by an unambiguous route via 3, 4-dihydro-7-methoxy-4, 6-dimethyl-1 (2H) -naphthalenone (19) prepared from 4- (4-methoxy-3-methylphenyl) pentanoic acid (4).

View full abstract

Barium hydrogenfluoride (BaHF₃) as raw material for zirconium (IV) fluoride-optical fiber was purified by solvent extraction, sublimation and fluorination with hydrofluoric acid. Barium acetate was the best starting material for the preparation of high-purity BaHF₃. Trace impurities of iron, cobalt, nickel and copper in the BaHF₃ and oxygen in the zirconium (IV) fluoride glass containg BaHF₃ were determined by neutron activation analysis and charged particle activation analysis, respectively. It was found that the amounts of hydrofluoric acid and oxygen in the prepared BaHF₃ affect the transmission loss in the fluoride-optical fiber. The analytical results for hydrofluoric acid, transition elements and oxygen in the prepared BaHF₃ showed that the solvent extraction, the sublimation and the fluorination by hydrofluoric acid are the best methods for the preparation of high-purity BaHF₃ for a low-loss zirconium (IV) fluoride-optical fiber.

View full abstract

Complexation behavior of crown ethers with lithium and sodium ions under competitive conditions has been assessed by use of FAB mass spectrometry and shown to correlate with the results obtained in the competitive transport experiments in presence of crown ethers and phosphoric acid esters. The FAB/MS technique gave information about competitive complexation by using relatively small quantities of the ligands.

View full abstract

Dialdehyde cellulose (DAC), modified by chitosan coating (chitosanDAC) and iron chitosan complex, developed as oral sorbents for urea and phosphate removal, were reported in previous papers. In this paper, chitosanDAC, iron chitosancomplex and chitosan were tested for removal of uric acid, quinolinic acid, trans-aconitic acid and 2, 5-furan dicarboxylic acid, which are main acidic substances existed in uremic toxins. In-vitro experiments have shown that chitosanDAC and chitosan remove these acidic substances by adsorption in high rate and capacity. Chronic renal failure rats were fed on the standard diet with or without chitosanDAC (5 % content)for about two months. Rats received chitosanDAC showed 8 % decrease of blood uric acid compared with rats received the normal diet.

View full abstract

Metal-support interaction (MSI) in catalysts supported on silica was studied with model catalyst sys tems in which metal particles were deposited on a thin film silica surface. X-Ray photoelectron spectroscopy on these model catalyst surfaces revealed the formation of charge-reduced Si⁴⁺ species due to the deposition of metal particles. The amount of the charge-reduced Si⁴⁺ species paralleled the amount of the metal deposited on the surface.

View full abstract