The shuttling process of alpha-CyD in three rotaxanes (1-3) containing alpha-cyclodextrin (alpha-CyD) as a ring, azobenzene as a photoactive group, viologen as an energy barrier for slipping of the ring, and 2,4-dinitrobenzene as a stopper was investigated. The trans-cis photoisomerization of 1 by UV light irradiation occurred in both DMSO and water due to the movement of alpha-CyD toward the ethylene group, while the photoisomerization of 2 occurred in DMSO, but not in water. No photoisomerization was observed for 3 in both water and DMSO. The activation parameters of 1 and 1-ref in DMSO are subject to a compensation relation between deltaS(double dagger) and deltaH(double dagger); however, in water, the deltaS(double dagger) terms are not compensated by the deltaH(double dagger) terms. Alternating irradiation of the UV and visible lights resulted in a reversible change in the induced circular dichroism (ICD) bands of trans-1 and cis-1. In contrast, after the UV light irradiation, the ICD band of trans-2 decreased without the appearance of any bands of cis-2. The NMR spectra of 2 in DMSO showed coalescence of the split signals for the methylene and for the viologen protons due to the shuttling of alpha-CyD. Both the NOE differential spectra for cis-1 in water after UV light irradiation and 2 in DMSO after heating to 120 degrees C showed the negative NOE peaks assigned to interior protons of alpha-CyD, suggesting that alpha-CyD in cis-1 exists at the one ethylene moiety, and alpha-CyDs in cis-2 and 2 heated in DMSO exist at the propylene moieties.

Bilayer graphene (BLG) comprises a 2D nanospace sandwiched by two parallel graphene sheets that can be used to intercalate molecules or ions for attaining novel functionalities. However, intercalation is mostly demonstrated with small, exfoliated graphene flakes. This study demonstrates intercalation of molybdenum chloride (MoCl ) into a large-area, uniform BLG sheet, which is grown by chemical vapor deposition (CVD). This study reveals that the degree of MoCl intercalation strongly depends on the stacking order of the graphene; twist-stacked graphene shows a much higher degree of intercalation than AB-stacked. Density functional theory calculations suggest that weak interlayer coupling in the twist-stacked graphene contributes to the effective intercalation. By selectively synthesizing twist-rich BLG films through control of the CVD conditions, low sheet resistance (83 Ω ▫ ) is realized after MoCl intercalation, while maintaining high optical transmittance (≈95%). The low sheet resistance state is relatively stable in air for more than three months. Furthermore, the intercalated BLG film is applied to organic solar cells, realizing a high power conversion efficiency.

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In Japan, two species of the genus Reclinervellus were found to attack a single host spider, Cyclosa octotuberculata (Araneae). One of these, Reclinervellus tuberculatus comb. nov., winters as a tender larva and has at least two generations a year. This species laid its egg on the anterior face of the host's abdomen. Prior to laying an egg the female repeatedly rubbed her ovipositor over the dorsal and lateral surfaces of the host's abdomen near the base for more than 25 min. The hatched larva fixed itself at the position where the egg was laid, and developed by consuming the host's body fluids. The other species, R. masumotoi sp. nov., is closely related to R. tuberculatus but is easily distinguished from it by having a very weakly reclivous Cu vein in the hindwing, a less developed carina of the propodeum, a shorter ovipositor and more blackish coloration of the mesoscutum. Although this species is sympatric with R. tuberculatus and attacks the same host, the position of the egg and larva on the host's body is quite different from that of R. tuberculatus. The egg of this species was laid on the posterior surface of the host's abdomen and the larva matured 10-20 days earlier than those of R. tuberculatus. Via these modes of parasitism R. masumotoi seemed to escape from competition with R. tuberculatus at the stage of oviposition and out-competed it when a single host individual bore larvae of both species. Previous records of parasitoids reared from C. octotuberculata were reviewed and found to include records of both species.