Mesostructured materials containing niobium in the framework were prepared using layered-perovskite type potassium niobium oxyfluoride and hexadecyltrimethylammonium chloride. The meso- and localstructure were characterized by X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) analysis. XRD analysis showed that lamellar structure was formed in the materials prepared at pH 10.5. EXAFS analysis showed that octahedral Nb0₆ unit of the materials at pH 10.5 have the linkages of edge-shared structure. The both analysis also showed that mesostructured materials prepared at pH 3.0 had 2d-hexagonal structure and the number of linkages of edge-shared structure decreased.

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The road surface repair material of cold hardening type was tested for workability such as self-leveling, hardened properties, and hardening time for opening the traffic. The flow test was suitable for testing on self-leveling characteristics and the allowable flow time for the characteristic was 4 to 10 s and the handling time after mixing was 10 min at 20°C. The properties of hardened repair material were almost the same as those of a dense-grade hot asphalt mixture. The rutting resistance was superior to the dense-grade hot asphalt mixture. Flexural property and strength of this road repair material were satisfactory for bonding on the existing road surface. Its hardening time could be evaluated by using the durometer with semi-globular shape type of press needle and the hardness for early opening the traffic was approximately 85 at 60 min after finishing the repair work at 20°C.

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Post-synthetic procedure has been proposed using organo-titanium compounds as Ti source in toluene or aqueous solution to prepare Ti-MCM-41. Ti-MCM-Tn, prepared using Ti-source dissolved in toluene solution, exhibited well-defined 2d-hexagonal structure, and octahedrally coordinated Ti (VI) was mainly introduced as extra-framework species. Ti-MCM-Wn, prepared from Ti-source in aqueous solution, gave high surface area and partially deteriorated 2d-hexagonal structure. Tetrahedrally coordinated Ti (IV) species was selectively incorporated into the framework of the Ti-MCM-Wn samples. Catalytic activity for oxidation reactions of cyclohexene and selectivity to the formation of cyclohexene oxide were correlated with the concentration of Ti (IV) species and the fraction of Ti (IV) in titanium species located at the surfaces of the pores in the Ti-MCM catalysts, respectively.

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A new system for detecting the sub-harmonic component of ultrasonic pulse waves is constructed using a double-layered piezoelectric transducer (DLPT). The resonance frequency of the DLPT comprising two transducers (with resonance frequencies of f_o) is equal to f_o/2 when the transducers are connected in parallel and f_o when the transducers are connected in series. The performance of the DLPT used in this ultrasonic system is described. Based on the experimental results, the sub-harmonic component of the ultrasonic pulse waves reflected by the reflector is efficiently extracted and an improved sensitivity of approximately 30 dB is obtained, as compared with that afforded with a conventional system constructed without a switching.

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Mesoporous molecular sieves (NCZ-MCM-41) with ordered hexagonal structure have been synthesized from natural clinoptilolite zeolite (NCZ) with cetyltrimethylammonium bromide micelle under hydrothermal conditions in alkaline media. Zeolite P was also formed from NCZ under the conditions studied. The samples were characterized by XRD, N₂ adsorption and IR. It is indicated that the pore walls of the NCZ-MCM-41 may probably contain the secondary building units similar to NCZ and zeolite P.

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Three crystal structures of p-sulfonatothiacalix [6] arene (1) inclusion complexes with octa-aqua lanthanide metal ions (M=Gd³⁺, Ho³⁺, and Er³⁺) have been determined by single crystal X-ray diffraction studies. Three structures show a same conformation as “up-down” double partial cone conformation. The aquated lanthanide metal ions were captured in the “up-down” cavities of thiacalixarene. In the overall their crystal structures, supramolecular assemblies are formed by hydrogen bonds and π-π staking interactions.

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