Chalcopyrite-type CuInS 2 -based alloyed fluorescent nanocrystals (NCs), which contain no regulated heavy metal ions, were synthesized by heating an organometallic solution to demonstrate optical property tunability. Introduction of Zn into the CuInS 2 system enhanced their photoluminescence (PL) intensity. The resultant particles were 3-6 nm; they varied with experimental conditions and were discrete and colloidally stable. The band-gap energy and PL wavelength of Zn-Cu-In-S (ZCIS) NCs varied with Zn content and particle size. Their PL was controllable within 570-800 nm by altering the band-gap energy. Furthermore, indium substitution with gallium was shown to control band-gap energy toward ∼3.1 eV, 500 nm of PL wavelength. In addition, ZnS coating of this nanocrystal can approximately double the PL strength. Finally, surface treatment with mercaptoundecanoic acid dispersed hydrophilic ZCIS NCs into water.

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Life histories of low-level misocyclones, one of which corresponded to a tornado vortex within a winter storm in the Japan Sea coastal region on 1 December 2007, were observed from close range by X-band Doppler radar of the East Japan Railway Company. Continuous plan position indicator (PPI) observations at 30-s intervals at the low-elevation angle revealed at least four cyclonic misocyclones within the head of the comma-shaped echo of the vortical disturbance under winter monsoon conditions. The meso-b-scale vortical disturbance developed within the weak frontal zone at the leading edge of cold-air outbreaks.High-resolution observation of misocyclones revealed the detailed structures of these misocyclones and their temporal evolution. As the parent storm evolved, a low-level convergence line was observed at the edge of the easternmost misocyclone. This convergence line was considered to be important for the initiation and development of the misocyclones and the tornado through vortex stretching. The strongest misocyclone gradually intensified as its diameter contracted until landfall, and then began to dissipate soon after landfall. The temporal evolution of the misocyclones through landfall is discussed.Surface wind and pressure variations suggested a cyclonic vortex passage, which was consistent with the passage of the radar-derived misocyclone. The observed pressure drop was also consistent with that computed from the cyclostrophic equation for the modified Rankine vortex. The observed behavior of two adjacent misocyclones was primarily consistent with the rotational flow associated with the other misocyclone. The generation and development processes of the tornado and misocyclones are discussed.