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The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids.

Local ordering in co-deposits of water and xenon atoms produced at low temperatures can be followed uniquely by 1 2 9 Xe NMR spectroscopy. In water-rich samples deposited at 10 K and observed at 77 K, xenon NMR results show that there is a wide distribution of arrangements of water molecules around xenon atoms. This starts to order into the definite coordination for the structure I, large and small cages, when samples are annealed at ∼140 K, although the process is not complete until a temperature of 180 K is reached, as shown by powder X-ray diffraction. There is evidence that Xe . 20H 2 O clusters are prominent in the early stages of crystallization. In xenon-rich deposits at 77 K there is evidence of xenon atoms trapped in Xe . 20H 2 O clusters, which are similar to the small hydration shells or cages observed in hydrate structures, but not in the larger water clusters consisting of 24 or 28 water molecules. These observations are in agreement with results obtained on the formation of Xe hydrate on the surface of ice surfaces by using hyperpolarized Xe NMR spectroscopy. The results indicate that for the various different modes of hydrate formation, both from Xe reacting with amorphous water and with crystalline ice surfaces, versions of the small cage are important structures in the early stages of crystallization.

The stereoselective phosphorylation of D-glucopyranose has been achieved using inorganic sodium cyclo-triphosphate hexahydrate (P3m), Na3P3O9·6H2O. The reaction product has been confirmed to the β-D-glucopyranosyl 1-triphosphate by multinuclear NMR and HPLC, and its maximum yield was about 47%.

A new synthetic method of sulfoxides and sulfones using solvent-free oxidations of sulfides with urea–hydrogen peroxide complex (urea–H 2 O 2 ) and tetrabutylammonium phosphomolybdate catalyst on fluorapatite ((Bu 4 N) 3 [PMo 12 O 40 ]/FAp). In the solid-phase system the oxidations of aromatic and alkyl sulfides proceeded at 4–25 °C and the corresponding sulfoxides or sulfones were selectively obtained in good yields by controlling the amount of urea–H 2 O 2 .

We found that Keggin-type phosphometalates are effective catalysts for solvent-free oxidation with urea–H2O2 by dispersing on fluorapatite solid phase. In the solid phase system the phosphomolybdate (NH4)3PMo12O40 was more effective than the phosphotungstate (NH4)3PW12O40, whereas the latter was much superior to the former in the liquid-phase reaction with aqueous H2O2. In situ formation of novel peroxo-type species from (NH4)3PMo12O40/FAp and urea–H2O2, which may lead to the high catalytic activity in the solid phase system, was observed by 31P solid-state NMR.

In this paper, we report the synthesis, spectral and magnetic properties, and X-ray crystal structure of the unique mononuclear iron(III) complexe

The temperature dependences of 81Br nuclear quadrupole resonance frequencies and quadrupolar relaxation times of Cs2ZnBr4 were measured. The librational motion of [ZnBr4]2− about the Zn–Br axis parallel to the a axis in the crystal is more active than those about the other axes. The reason why this compound shows no phase transition can be accounted for by the molecular packing, especially the packing of [ZnBr4]2− along the a axis. General examination of the relative size of cation/anion in the class of compounds of A2MX4 type led to a criterion which may be used to rationalize existence and absence of a phase transition.