The macroscopic motion of liquids on a flat solid surface was manipulated reversibly by photoirradiation of a photoisomerizable monolayer covering the surface. When a liquid droplet several millimeters in diameter was placed on a substrate surface modified with a calix[4]resorcinarene derivative having photochromic azobenzene units, asymmetrical photoirradiation caused a gradient in surface free energy due to the photoisomerization of surface azobenzenes, leading to the directional motion of the droplet. The direction and velocity of the motion were tunable by varying the direction and steepness of the gradient in light intensity. The light-driven motion of a fluid substance in a surface-modified glass tube suggests potential applicability to microscale chemical process systems.

The phase structure of the stereocomplex (DILIP) prepared from poly(D-lactic acid) (PDLA) and poly(L-lactic acid) (PLLA) in a dilute acetonitrile solution has been examined by high-resolution solidstate 13C NMR spectroscopy. Three resonance lines I-III appear at 173.3,172.0, and 169.7 ppm respectively, for the carbonyl carbons of DILIP. Line I is further resolved into two components with 13C spin-lattice relaxation times (Tic) of 128 and 17 s at 113 °C, whereas lines II and III are composed of single components with Tic = 40 and 5.4 s, respectively. The components with Tic = 128 and 17 s for line I can be assigned to the rigid and disordered racemic crystalline components, respectively. Line III is the contribution from the noncrystalline region, where the segments of PDLA and PLLA may be almost randomly mixed. Moreover, line II may be ascribed to the crystalline component of homopolymers incidentally produced. The total spectrum reflecting quantitatively all the components has been resolved into those four components by a line shape analysis. The degree of crystallinity estimated as a sum of mass fractions of the rigid and disordered racemic crystalline components is in agreement with that determined by differential scanning calorimetry or X-ray diffractometry. On the basis of the long period (12.0 nm) evaluated by small-angle X-ray scattering and mass fractions for the respective components, the thicknesses of the racemic crystalline and noncrystalline regions have also been determined to be 8.2 and 3.8 nm, respectively, by assuming the lamellar structure. is o-c -co-I CH, Thermal analyses, SEM observations, ED analyses, and polarimetry have already been performed on the PLA

Structural analysis of 70Li2S–30P2S5 glass ceramic by 31P MAS NMR revealed a strong correlation between the degree of crystallisation and the lithium ionic conductivity.

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