White LEDs are fabricated through a combination of blue LEDs with Sr3 SiO5 :Ce(3+) ,Li(+) phosphors and organically capped CdSe quantum dots (QDs), which exhibit a 2D superlattice. The combination of blue emission from the LEDs, greenish-yellow emission from the phosphors, and red emission from the QDs generates white light. As-synthesized white LEDs show excellent color rendering properties and stable color coordinates against increasing forward bias currents.

Aim This paper was designed to extend the extant research regarding factors related to nurses' turnover intentions. Methods This survey‐based study was based on a path analysis designed to verify a hypothesized causal model involving nurses' role stress, organizational commitment, turnover intentions, and burnout. This study distributed 500 questionnaires to nurses in general hospitals with more than 500 beds located in Seoul, Korea, during 16–30 April 2012. Results Role conflict, an underlying factor in role stress, had no significant effect on role stress, but the results showed that role ambiguity reduced organizational commitment. On the other hand, role conflict and role ambiguity increased the level of burnout. Organizational commitment reduced turnover intentions, and burnout increased turnover intentions. Role conflict and role ambiguity had no direct effect on turnover intentions, but they had indirect effects on organizational commitment and burnout. Conclusion To reduce nurses' turnover rate, this study recommends developing plans to improve their organizational commitment because it mediates role stress and turnover intention.

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A novel blue-emitting phosphor, Na(0.34)Ca(0.66)Al(1.66)Si(2.34)O(8):Eu(2+) (NCASO:Eu(2+)), was prepared by a wet chemical synthesis method based on the hydrolysis of tetraorthosiliate (TEOS) and confirmed the formation of NCASO:Eu(2+) from Rietveld analysis. Photoluminescence (PL) results showed that the phosphor can be efficiently excited by UV light from 250 to 420 nm, and emitted bright broad blue emission, which has maximum intensity at around 445 nm. Under 365 nm excitation, the PL emission intensity area of optimized NCASO:Eu(2+) was found to be 99.72% of that of a commercial BaMgAl(10)O(17):Eu(2+) (BAM:Eu(2+)) phosphor. Moreover, the optical absorbance, internal quantum efficiency, and external quantum efficiency of NCASO:Eu(2+) were calculated to be 112%, 94%, and 105% of that of the commercial BAM:Eu(2+) phosphor, respectively. The WLEDs were fabricated using the blue NCASO:Eu(2+) phosphor, a green-emitting β-SiAlON:Eu(2+), and a red-emitting CaAlSiN(3):Eu(2+) phosphors with a near-UV chip. The WLED device exhibited an excellent color-rendering index R(a) of 94 at a correlated color temperature of 5956 K with CIE coordinates of x = 0.323, y = 0.335. These results suggest that NCASO:Eu(2+) is a promising blue-emitting phosphor for UV LED applications.

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