The effect of temperature on adsorption isotherms of Ar, N2, O2, C2H4, and CO2 on mesoporous MCM-41 molecular sieves with different pore sizes (pore radius rp ) 1.2, 1.4, 1.8, 2.1 nm) has been measured. The occurrence of adsorption hysteresis upon capillary condensation of these molecules in mesopores depends on their capillary critical temperatures (Tcc), which are far below the corresponding bulk critical temperatures (Tc). In accord with theoretical predictions of confined geometry effects on the criticality of fluids in narrow pores, a plot of (Tc -Tcc)/Tc against d/rp for Ar, N2, O2, and C2H4 seems to form a single straight line passing through the origin, where d is the molecular diameter. The data for CO2 deviates from this relationship. These results are compared with critical point shifts of fluids in conventional mesoporous adsorbents with an interconnected network of pores available in the literature.

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White emission is important for applying organic EL devices to full-color displays and backlighting. In order to obtain white emission, the use of a white-light-emitting material which shows the white emission by itself is advantageous for these applications because of its high reliability and productivity. A device structure of indium-tin-oxide (ITO, anode)/hole transport layer/emitting layer/MgIn alloy (cathode) was employed. Bis(2-(2-hydroxyphenyl)benzothiazolate)zinc ( Zn(BTZ)2) was used as the emitting material. Zn(BTZ)2 showed greenish-white emission with a broad electroluminescent spectrum (half-width: 157 nm, peak wavelength: 486, 524 nm). It exhibited a high luminance of 10,190 cd/m2 at the applied voltage of 8 V because Zn(BTZ)2 has a good electron-transport property. As such, Zn(BTZ)2 is expected to serve as a new white-light-emitting material for organic EL devices.

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