Much attention is now focussed on the stereo- and regiocontrol of 1, 3-dipolar cycloaddition reactions by the aid of a Lewis acid catalyst. The report of catalyzed asymmetric nitrone cycloadditions has triggered the acceleration of research development of this field. This review describes the Lewis acid-catalyzed nitrone cycloadditions to electron-deficient alkenes, the Lewis acid-catalyzed nitrone cycloadditions to electron-rich alkenes such as allylic alcohols, and asymmetric nitrone and aci-nitro compound cycloadditions to electron-deficient alkenes catalyzed by DBFOX/Ph metal complexes.

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Species specificity and regioselectivities in the photocycloadditions of some conjugated enones and dienones were confirmed to be controlled by the interaction between frontier molecular orbitals (FMO’s), calculated using PM3-CI level. The peri-([2+2] or [4+2]), site-(3, 4- or 5, 6-addition) and regioselective photoadducts in the triplet photoreactions of 2-pyrones with electron-deficient or electron-rich alkenes were considered to be formed through the regioselective 3-β or 6-β two-center interactions at the first-steps, and periselective ring-closures from the biradical intermediates. Regio-, site- and stereoselective [2+2]cycloadducts from the excited singlet or triplet reactions of 2-pyridones with proper electron-deficient alkenes were also confirmed to be caused mainly through the orbital and static four-center interactions, or biradical formation followed by ring-closure.
The regioselectivity difference between the photocycloadditions of two cyclic enones, such as 2-cyclohexenone and 2-cyclopentenone were similarly analysed by the FMO method. The regioselectivity of the enones was concluded to be controlled mainly by the FMO interactions at the first-steps and by the relative reactivity of the following ring closure of the biradical intermediates from cyclopentenone.
Relationship between the species specificity and site-, regio- and periselectivities in the photocycloadditions of cyclic conjugated enones and dienones could be interpreted from their FMO properties.

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Iridium catalysts supported on MFI-type metallosilicates with activation treatment in 10%H₂O-N₂ at 700°C showed very high NO_X reduction activity at 300-500°C under oxygen rich condition.
The activated catalyst showed stable NO_X reduction activity in lean burn atmosphere with steam gas and rich atmosphere gas treatment and was durable to SO₂-poisoning.
This catalyst had stable NO_X reduction activity in continuous treatment at 450°C of lean burn gas atmosphere, but showed catalytic deactivation in continuous treatment over 500°C of lean burn gas atmosphere. However, the activity of deactivated catalyst is easily regenerated by the lean/stoichiometry alternate gas treatment. Moreover, this catalyst showed stable NO_X reduction activity of lean/stoichiometry alternate atmosphere gas treatment for 450h.
The characterization by XRD and XPS revealed that the reason of catalytic deactivation in continuous treatment of lean burn gas atmosphere was in the form of Ir oxide around the Ir-metal surface. Ir oxide around the Ir-metal surface is easily removed by the hydrocarbon treatment in the stoichiometry gas atmosphere.

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Multicomponent oxalate consisted of Fe³⁺ and M²⁺(M=Ni, Cu, Co, Zn) was prepared by heating the polyethylene glycol (PEG) solution of metal nitrate hydrate at 358K for 3h. The PEG-cation complex in the solution was oxidized by the nitrate ion so that the oxalate was obtained. The structure and the composition of the cations in the obtained oxalate depended on not only the composition of the PEG solution but also the molecular weight of PEG. The crystallinity and the particle size of the oxalate increased with an increase of the molecular weight of PEG. The relation between the cation composition in the PEG solution and that in the obtained oxalate also depended on the molecular weight of PEG. The two models that describe the formation process of the PEG-cation complex and the oxalate was examined. In the first model, it is assumed that the coordination of Fe³⁺ ions and that of M²⁺ occurs independently. In the second model, it is assumed that the coordination of Fe³⁺ and that of M²⁺ occurs cooperatively. The relation between the cation composition in the PEG solution and that of the obtained oxalate was derived from these models. According to the comparison between the experimental result and the consequences derived from the models, it is shown that the coordination of M²⁺ to PEG always occurs near the site where the coordination of Fe³⁺ occurred. The PEG-cation complex was formed under the cooperative process.

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A new type both-end-capped poly(oxymethylene) with a long alkyl group was synthesized. Using formaldehyde methyl octadecyl acetal as the chain transfer agent for the polymerization of trioxane, the both-end-capped poly(oxymethylene) with a methoxy group and octadecyloxy group was obtained. Almost all the formaldehyde methyl octadecyl acetal in the polymerization mixture is consumed. Formaldehyde methyl octadecyl acetal is confirmed to be chemically bonded in poly(oxymethylene) derived from ¹H-NMR measurements. For the case of using formaldehyde di(octadecyl) acetal as the chain transfer agent, almost all the formaldehyde di(octadecyl) acetal in the polymerization mixture is consumed. Direct proof that formaldehyde di(octadecyl) acetal is chemically bonded in poly(oxymethylene) was obtained. The reduced viscosity of the polymer showed a complicated behavior. This suggested that some aggregation of the octadecyl group of the polymer chain-end took place in the solution. For the case using formaldehyde methyl acetal of the carbon number 38 alcohol, the polymer obtained showed the melting behavior at 95°C, which could be attributed to the melting of the long alkyl group. The reduced viscosity also suggested an aggregation of the long alkyl group of the polymer chain end in the solution. The observed amount of the C₃₈H₇₇ group, which was calculated from the observed value of methylene linkage by ¹H-NMR, was lower than the calculated value based on the feed C₃₈H₇₇OCH₂OCH₃. This fact suggests that the methylene linkage of the C₃₈H₇₇ group may provide a strong aggregation in the solution.

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This study discusses the influence of K₂HPO₄ or CaSO₄·2H₂O on the hydration of alite, a main composition of ordinary Portland cement. The early stages of hydration were measured by a conduction calorimeter. The added amounts of K₂HPO₄ or CaSO₄·2H₂O were from 0 to 3% (counted as P₂O₅) or from 0 to 10% (counted as SO₃), respectively. The rate of heat liberation of alite was retarded by the addition of K₂HPO₄ and accelerated by the addition of CaSO₄·2H₂O. At 1.5% K₂HPO₄ addition, the retardation effect of K₂HPO₄ showed a maximum. On CaSO₄·2H₂O addition, as the amount of CaSO₄·2H₂O increased, the acceleration effect of CaSO₄·2H₂O increased.
The reaction ratio of alite was measured by XRD at late stage of the hydration.
Calcium silicate hydrates produced by hydration of alite with 1.5% K₂HPO₄ or 4% CaSO₄·2H₂O included P₂O₅ or SO₃, respectively. These CaO/SiO₂ ratios of calcium silicate hydrates were higher than that of alite without additives. Calcium silicate hydrates could contain P₂O₅ or SO₃ with CaO, and P₂O₅ and SO₃ influenced the morphology of produced calcium silicate hydrates.

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Additives used in industrial arts of lacquer tree paint were systematically classified into 9 groups of reagents from the components involved in them and the effect of the reagents on the reactivity of lacquer tree paint was investigated and discussed on the basis of reversed micelle structure of urushiol. The effects of the reagents added on the curing reaction, the chemical reaction of catechol ring of urushiol, and their reactivity were examined by measurements of curing time and discoloration of paint film, and mass analysis of thermally eliminated molecules from paint film, respectively.
From the results obtained in the present study, phenol compounds, aromatic amines, aliphatic amines, and unsaturated fatty acids having more than two double bonds were found to be reactive with urushiol. Furthermore, the effect of the acceleration or the inhibition of reagents added on the reactivity of urushiol was confirmed to be dependent on their molecular structure.

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Heavy oils sorbed into exfoliated graphite, 80g of heavy oil per 1g of exfoliated graphite, could be recovered by both a simple compression and suction filtration with the recovery ratio of 50-80%. In the comparison of the original exfoliated graphite and the exfoliated graphite after suction filtration to recover the heavy oil, a balloon-like texture of the exfoliated graphite is still observed, indicating that the exfoliated graphite can be recycled. Recovered oil showed no differences in molecular weight and hydrocarbon constituent from the original one. No increase of water content in the recovered oils was detected, suggesting preferential sorption of heavy oil into the exfoliated graphite.

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We tried to find out the optimal carbon black (CB) properties which would effectively increase the thermal durability of CB/Silicone rubber compound, through verification of the correlation between CB properties and the thermal durability. For the purpose of this study, we selected eight CB properties, namely primary particle size, structure, ash content, sulfur content, toluene coloring transmittance, crystalline thickness (L_c), volatile materials and a new indicater (O/S) which is the content of oxygen per unit CB surface area. We examined 12 kinds of CB. The thermal durability of CB containing rubber was significantly improved when the CB content was between 0.5 and 1.0phr. L_c and the thermal durability showed a correlation and the smaller value of L_c (which was related to the thermal history in CB production furnace) exhibited the better thermal durability. CB whose O/S value was greater than 0.14mg/m² gave good thermal durability for the compound. However, the other properties did not display a correlation to the thermal durability of the composit. Consequently, it is suggested that CB, which possesses a good ability for capturing radicals in the compound, effectively improves thermal durability.

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Bis(sulfophenyl) phosphonate-formaldehyde resin was prepared by the reaction of diphenyl phosphonate-formaldehyde resin with fuming sulfuric acid. This resin was used as an acid catalyst for esterification of benzoic acid with saturated primary alcohols as well as saturated secondary alcohols. The yields of the esters formed with saturated primary alcohols(C₁-C₉) were 62-73% at 100°C, and with secondary alcohols(C₃-C₉) were 11-47% (100°C).

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