Recent research trends and technology on thermostable alkaline detergent additives such as “over -based sulfurized calcium phenates” and “sulfurized calcium salicylates” which are essential to the lubricating system in internal combustion engine were critically discussed.
The method for preparing “over-based sulfurized calcium phenates” consists usually of the sulfurizing and the over-basing process, the latter of which is focussed recently.
Hitherto, the reaction of a large excess calcium reagents with alkylphe nol was used for preparing “over-based sulfurized calcium phenates”, but a novel method with a reverse blending ratio has been developed.
The method for preparing “sulfurized salicylates” consists generally of the carboxylating and the sulfurizing process, and the later process has been mostly studied. However, a new method of carboxylation has been recently developed, and a sharp cut of preparing steps becomes possible.
Alkaline detergent additives are of complicated composition and their structure is not sufficiently clear. Our results on this respect are also described.
Both the newly developed methods for preparing th e “over-based sulfurized calcium phenates”and the “sulfurized calcium salicylates” are simpler and it was demonstrated that the products by our methods have excellent thermal stability and also superior performance.

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The first band in the electronic absorption spectra of 1-methyl-4-(4-diethylaminophenylazo)pyridinium iodide (MDP) is shifted to the red with increasing polarity of the solvent, indicating that this band is not to be assigned to the charge transfer (from I^- to pyridinium moiety as observed in 1-methylpyridinium iodide) band, but to the usual π-π^* transition not participated by I^-. It is also found from the spectral changes of electronic absorpiton spectrum and ¹³C-NMR spectrum of MDP induced by protonation that the first protonation of MDP takes place only at amino nitrogen, not taking place at azo nitrogen. An absorption band, attributable to the protonated species of MDP produced by the protonation at amino nitrogen, is observed in the electronic absorption spectrum of MDP adsorbed on the surface of the borosilicate glass plate only when the glass surface is wet with water. This observation suggests that the interaction between the MDP molecule adsorbed and the glass surface wetted with water is related to the protonation at amino nitrogen; the π-type lone pair electron on amino nitrogen of MDP seems to interact with the acid site of the Lewis acid type, the vacant orbital of boron, on the glass surface indirectly through water. In other words, this lone pair electron seems to interact with the proton produced from the water molecule bonded to the vacant boron orbital.

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A series of inorganic salts was dissolved in poly(ethylene oxide) (PEO) with average molecular weight of 200-6000 to determine their solubility. The solubility of lithium salts in PEO decreased with the increase of PEO molecular weight. The terminal hydroxyl group was revealed to be much more effective to increase solubility of the added salts than ether oxygen. Sodium salts showed PEO molecular weight dependence on the solubility similar to that for the lithium salts. Little molecular weight dependence of PEO was however found in the solubility of potassium salts. From a structural analogy between water molecule and the hydroxyl group, solubility order among inorganic salts in PEO was expected to be similar to those in water, but no relation was found. The maximum ionic conductivity for PEO (molecular weight: 200)/LiclO₄ system was found at [LiclO₄]=1.0 mol/l. This was demonstrated to be attributed to the matrix viscosity. Higher ionic conductivity was observed in the PEO systems containing 0.3 mol/l salt with larger cation radius and those with lower lattice energy.

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A microcomputer-controlled instrument for measuring precise surface shear viscosity of monolayers at the air/water interface by the canal method was constructed. The surface shear viscosity of 1-octadecanol monolayers on water surface at 20 °C was measured with this instrument using 22 kinds of canals of various length and width. It was observed that 1octadecanol monolayers in the liquid-condensed state obeyed Newtonian flow as a whole but the viscosity increased considerably with decreasing length and increasing width of the canal. This is caused by the kinetic energy effect of the flow of monolayers, which has not been reported in two-dimensional flow. The surface shear viscosity of 1-octadecanol monolayers obtained by the flow from 10 mNim to 5 mN/m at 20 °C was 2.25±0.10 μPa·s·m in average.

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Reactivity of ammonia adsorbed on reactivated pitch based active carbon fiber (ACF-OG-5 A)surface was studied at room temperature against NO in dry and wet air to find ACF of proper reactivation of which adsorption ability of ammonia could be regenerated under the above conditions.
The temperature for sulfuric acid reactivation was found to be very influential on the reactivity of adsorbed ammonia as well as ability of ammonia adsorption. Between 250 to 500 °C, the reactivation temperature of 400 °C appears to be the best to provide the longest adsorption ability for the regeneration by NO in a wet air of 100% relative humidity. The reactivation temperature is critical for the decomposition of surface oxygen groups which are produced by adsorbed H₂SO₄ and govern both ammonia adsorption and hydrophilic properties of ACF surface. A particular temperature of 400 °C may balance the ammonia adsorption ability and hydrophilic properties by leaving a fairly large number of acidic oxygen-containing groups and removing most of hydrophilic groups on the ACF surface as correlated to the amount of CO₂ and CO evolution in the temperature programmed decomposition of ACFs.
The roles of graphitic structure of the pitch based ACF may also be essential to show hydrophobic after the heat treatment.

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The naturally. occurring zeolite at Nishiaizu-cho, Fukushima-prefecture was used in this work. This was mainly composed of clinoptilolite with quartz, α-cristobalite and smectite clay minerals.
The structure of clinoptilolite was stable for the heat treatment below 600°C. But it was changed above 600°C, and the specific surface area (S. S. A.) and cation exchange capacity (C. E. C.) decreased. Thus, the uptake for Pb(II) decreased by heat treatment above 600°C.
The adsorption isotherms were found to be fitted by the Freundlich equation on both untreated and treated zeolites.
The adsorption proper ties for Pb(li) was studied using original, heat-treated and chemically treated zeolites.
Pb(II) was effectively adsorbed on the natural zeolite at pH 2.0-8.0.
The uptake for Pb(II) substantially increased on the zeolite hydroth ermally treated with sodium hydroxide, in comparison with original or other treatd specimens. Its maximum uptake for Pb(II) was 5 times as much as original zeolite.
The hydrothermally treated zeolite with sodium hydroxide seems to be promising for removal of Pb(li) from waste water.

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The single crystals of Cr₃Si and Cr₅Si₃ were prepared by the high temperature copper solution method using metal chromium and silicon powders as starting materials in an argon atmosphere. The conditions for obtaining these crystals with one-phase materials and a relatively large size were determined. As grown Cr₃Si and Cr₅Si₃ single crystals were used for chemical analysis, and measurements of unit cell dimensions, Vickers microhardness and electrical resistivity.

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A new inorganic cation-exchange membrane was successfully prepared on a microporous alumina substrate by dipcoating an antimonic acid sol solution obtained from a mixture of antimonic acid sol: Si(OC₂H₅)₄: H₂O: C₂H₅OH: HCl=O.06: 1: 11: 6.8: 0.068 in molar ratio.
The thickness, resistivity and ion-exchange capacity of the membrane increased with an increase in the number of dipcoated times, while the limiting currnet density showed a tendency to decrease.
The ion-exc hange capacity, area resistivity, limiting current density and transport number of Na⁺ for the 10 times coated membrane were O.0061 meq·cm^-2, 186.2 Ω·cm², 0.96 A·dm^-2and O.70, respectively.
The mem branes could stand in 6 M hydrochloric acid or nitric acid aqueous solution at 80°C for 24 h without any change in ion-exchange capacity.

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Molybdophosphoric acid (PMo) reacts with malachite green, (MG⁺) to form colored complex in an acidic medium. This reaction can be assumed to be the formation of an ion associate (MG⁺-PMo) as follows: nHMG²⁺+H₃PMo₁₂O₄₀ → (MG⁺)_nH_3-nPMo₁₂O₄₀+ 2nH⁺ (n≤3) where HMG⁺2+ is a protonated form of MG⁺+. HMG²⁺ shows the absorption maximum at 446 nm, whereas the ion associate shows the absorption maximum at about 650 nm.

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Ultratrace amounts of mercury in solid and liquid samples containing iodide were determined by cold vapor AAS, following to heating evaporation by combustion of samples and concentration by gold amalgamation of mercury. Heating evaporation temperature, addition agent and washing solution were examined for several inorganic and organic mercury compounds.
1) Mercury in the inorganic and organic mercury compounds could be completely vaporized at the temperature over 600 °C.
2) It was not possible-to r emove suppression of mercury vaporization in iodide compounds by the addition of reagents.
3) Mercury vapo r evolved by heating was passed through a solution of 1 M sodium hydroxide or 1 M sodium hydroxide containing 15 mg/l Cu(II) and 0.2% Sn(II)Cl₂ to remove the suppression by iodide. The minimum concentration of iodide to interfere 5 ng of mercury was 100 μg(as I).
This method has been successfully applied to the determination of ultratrace amounts of mercury in various standard solid and liquid samples.

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1H, 1H, 2H, 2H, 3H, 3H-Tridecafluoro (4, 4-dimethylheptyl)silanes [3a-3c] were prepared from the corresponding polyfluoroalkene [1] and silanes HSiXY₂ {2a; X=Y =C1, 2b X=C1, Y=CH₃, 2c; X=Y=OCH₃} in the presence of hexachloroplatinic(IV) acid in good yields (71-90%; Scheme 1 and Table 1). The product silanes [3a, 3b] and Dimethyl(1H, 1H, 2H, 2H-tridecafluorooctyl)-chlorosilane [4] were used to prepare the corresponding new-type branched- and straight-fluorocarbonaceous bonded stationary phase (PES) for reverse-phase high-performance liquid chromatography (RP-HPLC).

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Infrared absorption spectra of model compound, dimethyl terephthalate [1a], of poly (ethylene terephthalate) (PET) and methyl p-methoxybenzoate [2a], of poly(ether ester)(PEET), in the presence of disperse dyes was investigated in tetrachloroethane solution. Their hydrogen-bonding interaction was disscussed.
Disperse dye [3], 4-hydroxyazobenzene, in terachloroethane exhibited an absorption band with a peak at 3575 cm-1 ascribed to hydroxyl group, and disperse dye [4], 4-anilino-3nitro-N-phenylbenzenesulfonamide, at 3343 cm^-1 to imino group. The addition of 1a and 2a to the above disperse dye solution resulted in a decrease of the absorbance at 3575 cm^-1 and 3343 cm^-1, and other new absorption bands appeared at lower frequency. Both results are attributed to hydrogen bonding. The same results were also observed for the model compounds of PET containing two p-phenylene groups [1b] and the three groups [1c], and the model compounds of PEET containing the two groups [2b] and the three groups [2c].

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The Reactions of 4, 6-Diamino-2H-1, 3, 5-thiadiazine-2-thione [1] were investigated. On treatment with alkali, [1] underwent isomeric change into 4-amino-1, 3, 5-triazine-2, 6(1H, 5H)-dithione, on the other hand dimethyl N-(N²-cyanoamidino)carbonimidodithioate [6]was obtained in the presence of methyl iodide. When the reaction of [1] with aliphatic amines were carried out in DMF, yellow precipitates formed at room temperature which on treatment with dil. aq. alkali produced 1-substituted 4, 6-diamino-1, 3, 5-triazine-2(1H)-thione [2] and 6-(substituted amino)-4-amino-1, 3, 5-triazine-2(1H)-thione [3]. On reac tion with excess of primary amine in refluxing THF, [1] afforded substituted guanidine and 1, 3disubstituted thiourea together with small amount of [2]. In the presence of acid, aniline reacted with [1] in refluxing water to give good yield of [2d].
The reactions of [2] were also investigated. For example 1-substituted 6-thioxo-5, 6dihydro-1, 3, 5-triazin-2, 5(1 H, 3 H)-dione [11] were obtained by the acid hydrolysis of [2].

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Yubari coal was reductively methylated in the absence of electron transfer agent (Miyake method, K/THF/CH₃I) and the structure of hexane soluble portion (HS, 9.90%) was investigated in detail by GPC-LC separation followed by GC-MS, NMR and IR analyses.
Typical reaction products consisted of reductive methylation products of na phthalene (6.9%in the HS), phenanthrene (0.7%), quinoline (0.2%) and naphthalene dimer (0.8%), and methyl ethers (1.2%) of reductive methylation products of naphthalene and phenanthrene. In addition, saturated compounds which were liberated from coal matrix collapsed were also contained. The saturated compounds consisted of biomarkers involving n-paraffins (5.20%in the HS), isoprenoid paraffins (0.9%), bicyclic monoterpenes (1.5%), tricyclic diterpenes (1.6 %) and pentacyclic triterpenes (1.4%).
The reductive methylation products were compared with those obtained by the Sternberg method (K/THF/naphthalene/CH₃I). It was found that the Sternberg-product was contaminated with the reductive dimerization products of naphthalene used as an electron transfer agent. Based on the structure of the reductive methylation products, solubilization mechanism of coal is discussed.

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The interfacial free energy is one of the main factor controlling the dispersion of the filler in polymer matrices. It is necessary to know the accurate value of the surface free energy of the filler for analysis of the dispersal properties of particles in polymer composites. The measurements of surface free energy of CB particles are very difficult for these powderlike shapes. The purpose of the present study is to measure the surface free energy of oxidized CB.
Carbon bla ck, Seast 300, 27 nm indiameter, was used as original CB, and two kinds of oxidized CB were prepared by oxidation for 3 h in 25% and 50% boiled nitric acid. IGC (inverse gas chromatography) measurements were performed with a Shimadzu gas chromat ograph GC-7 A with a TCD detector. The glass columns (2.1 m long, 3 mm in diameter) were used and a column temperature was 90 °C. Helium was used as a carrier gas. ESCA (electron spectroscopy for chemical analysis) measurements were performed with a JEOL photo electron spectrometer JSP-80 under a vacuum of 10^-6Pa. MgKα (10 kV, 10 mA)was used as X-ray source.
The dispersive co mponents of surface free energies of oxidized CB particles could be estimated by IGC and they were slightly increased by oxidation. The polar components of them estimated by ESCA as the atomic ratios [O]/[C] on the CB surfaces were greatly increased by oxidation. The values of the surface free energy of CB which are defined as the sum of the dispersive and polar components measured in this work agreed with the generally reported values.

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For a basic understanding of the promoting effect of Pd on SnO₂-based gas sensor, the dispersion of Pd (or PdO) particles as well as their electronic interaction with Sn02 were investigated for various Pd loading up to 5 wt% by means of TEM and XPS. The dispersed Pd particles were observed as clear TEM images, when supported on the SnO₂ particles calcined at 900 °C. They were rather spherical in shape at reduced state (Pd) but changed to hemispherical at oxidized state (PdO) (Fig.1), suggesting a better contacting interface between PdO and SnO₂ than that between Pd and SnO₂. Epitaxy to SnO₂ was observed for both Pd (Fig.2) and PdO. With increasing Pd loading, the mean particle size of Pd remained rather small (less than 5nm) up to 3 wt%, but it increased to 10 nm rather abruptly at 5 wt% (Figs.3 and 4). This behavior was well reflected on the total surface area of Pd particles per gram sample (S) and the density of Pd particles on the SnO₂ surface (m) both of which had a mximum at 3 wt% (Fig.5). The XPS binding energies (BEs) of Sn 3d and O1s for PdO-SnO₂ showed Pd-loading-dependent shifts to the lower energy side from those of pure SnO₂, becoming minimum at 3 wt% loading, whereas such shifts disappeared totally when PdO was reduced to Pd (Table 1 and Fig.7). It is understood that the BE shifts are brought about by the electronic interaction between PdO and SnO₂(Fig.6), their dependency on Pd loading being determined by the density of such PdO-SnO₂contacts on the SnO₂ surface (m) (Fig.8).

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It was clarified that 2-alkylthio-6-amino-4 H-1, 3, 5-thiadiazin-4-imine [4] iodide was obtained by reaction of 4, 6-diamino-2 H-1, 3, 5-thiadiazine-2-thione [1] with alkyl iodide. Compound [4] was unstable and its free base was immediately rearranged into 4-amino-6alkylthio-1, 3, 5-triazine-2-thiol [2]. In boiling water, hydroiodide of compound [4] was hydrolyzed to form 6-amino-4-mercapto-1, 3, 5-triazin-2(1H)-one [6] and amidinothiourea [7]. When hydroiodide of [4] was treated with alkyl iodide in the pres ence of alkali, N-(N²-cyanoamidino)carbonimidodithioate [8] was formed. Hydroiodide of [4] was reacted with amines at room temperature to give 4, 6-diamino-1, 3, 5-triazine-2(1H)-thiones [3]. The reactivities of 2-ethoxy-6-amino-4 H-1, 3, 5-thiadiazin-4-imine [5] prepared by ring closure of O-ethyl N-(N²-cyanoamidino)carbonimidothioate [9] were also investigated.

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The regeneration of nicotinamide-adenine dinucleotide (reduced form NADH) by the reduction of NAD+ with hydrogen gas was carried out in the presence of the hydrogenase from Alcaligenes eutrophus, and the synthesis of malic acid was attempted by a combination of the above system and malate dehydrogenase. After 2 h, the highest conversion of oxalacetic acid and turnover number of NAD⁺ were 64% and 13, respectively.

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We measured the low temperature ESR spectra of mixed aqueous solution of Cu(1T) ion and water soluble polymer and estimated the electron densities on dx²-y². orbital from anisotropy of g value and hyperfine coupling constant. The electron density relates to the deodorant efficiency of the deodorant material consisting of Cu (11) ion and the various polymer.

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