Microfluidic static droplet generated quantum dot arrays as color conversion layers for full-color micro-LED displays.

This paper presents an easy and intact process based on microfluidics static droplet array (SDA) technology to fabricate quantum dot (QD) arrays for full-color micro-LED displays. A minimal sub-pixel size of 20 µm was achieved, and the fluorescence-converted red and green arrays provide good light uniformity of 98.58% and 98.72%, respectively.

Synergistic melamine intercalation and Zn(NO3)2 activation of N-doped porous carbon supported Fe/Fe3O4 for efficient electrocatalytic oxygen reduction.

Developing inexpensive, efficient and good stability transition metal-based oxygen reduction reaction (ORR) electrocatalysts is a research topic of great concern in the commercial application of fuel cells. Herein, with zinc nitrate as activator, iron nitrate as active component and melamine as intercalating agent and nitrogen source, an N-doped porous carbon supported Fe/Fe3O4 (Fe/Fe3O4@NC) catalyst is successfully synthesized by an impregnation-calcination method combined with freeze-drying technique. The positive onset potential (E onset), half-wave potential (E 1/2) and limiting current density (J L) of the optimal Fe/Fe3O4@NC catalyst are 1.012, 0.90 V vs. RHE and 5.87 mA cm-2, respectively. Furthermore, Fe/Fe3O4@NC catalyzes ORR mainly through a 4e- pathway, and the yield of H2O2 is less than 5%. It also manifests a robust stability after 5000 CV cycles of ADT testing, and the half-wave potential is only negatively shifted 17 mV. The structural characterization and experimental results further suggest that the outstanding ORR electrocatalytic performance of the Fe/Fe3O4@NC catalyst benefits from the synergetic effect of zinc nitrate activation and nitrogen doping, which can greatly improve the specific surface area, thus better dispersing more metal active sites. This work puts forward a simple and practicable way for preparing high-performance non-noble metal-based biomass ORR electrocatalysts.

[Audiological assessment value of click-evoked auditory brainstem response combined with single stimulation of the auditory steady-state evoked response on normal young people].

OBJECTIVE: Analysis of normal young people multiple stimuli ASSR (m-ASSR), single stimuli ASSR (s-ASSR), C-ABR, PTA threshold, exploratory investigation of relevance of hearing test combination thresholds (C-ABR combines with 0.5, 1.0 kHz s-ASSR) predict behavioral thresholds, using a within-subjects design. METHOD: Forty-three normal hearing adults (86 ears) were treated with pure tone audiometry (PTA), m-ASSR, 0.5, 1.0 kHz s-ASSR, C-ABR. Data were analyzed by SPSS 18.0 for bivariate correlation analysis. RESULT: There was significant correlation between thresholds of hearing test combination and PTA,and the correlation coefficient (r) were 0.803, 0.650, 0.649, 0.734 at 0.5, 1.0, 2.0 and 4.0 kHz; while the correlation coefficient (r) between thresholds of m-ASSR and PTA were 0.48, 0.64, 0.57, 0.64. CONCLUSION: There is significant correlation between thresholds of hearing test combination and PTA, hearing test combination can be more accurate, more reliable assessment of adults with normal hearing threshold level.