Solution‐processed tetraphenyldibenzoperiflanthene (DBP) films are prepared with three popular solvents, including chroloform (CF), chrolobenzene (CB), and dichrolobenzene (ODCB). The absorption and photoluminescence (PL) spectra of the DBP solution and DBP film are investigated. The absorption spectra between the DBP film and DBP solution are similar, whereas the PL spectrum shape of the DBP film and DBP solution is completely different, originating from the DBP molecular aggregation in the film, causing conjugate expansion, which results in dimer luminescence. The DBP donor layer at 32 nm prepared from solvent of CF, CB, and ODCB achieves a power conversion efficiency (PCE) of 1.42%, 0.88%, and 0.48%, respectively. The annealing temperature and DBP thickness are optimized; the 32 nm‐thick active layer annealed at 50 °C achieves the highest performance. The CF‐DBP film represents an interpenetrating network morphology, slightly higher roughness and hole mobility, which may be the main contribution to the relatively higher photocurrent than the CB‐DBP and ODCB‐DBP devices. Herein, a simple guidance for preparing solution‐processed DBP films is provided and simultaneously its application on organic photovoltaic cells (OPVs) is expanded.

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The mixed linear model (MLM) has been widely used in genome-wide association study (GWAS) to dissect quantitative traits in human, animal, and plant genetics. Most methodologies consider all single nucleotide polymorphism (SNP) effects as random effects under the MLM framework, which fail to detect the joint minor effect of multiple genetic markers on a trait. Therefore, polygenes with minor effects remain largely unexplored in today’s big data era. In this study, we developed a new algorithm under the MLM framework, which is called the fast multi-locus ridge regression (FastRR) algorithm. The FastRR algorithm first whitens the covariance matrix of the polygenic matrix K and environmental noise, then selects potentially related SNPs among large scale markers, which have a high correlation with the target trait, and finally analyzes the subset variables using a multi-locus deshrinking ridge regression for true quantitative trait nucleotide (QTN) detection. Results from the analyses of both simulated and real data show that the FastRR algorithm is more powerful for both large and small QTN detection, more accurate in QTN effect estimation, and has more stable results under various polygenic backgrounds. Moreover, compared with existing methods, the FastRR algorithm has the advantage of high computing speed. In conclusion, the FastRR algorithm provides an alternative algorithm for multi-locus GWAS in high dimensional genomic datasets.

Unlike the traditional fabrication of distributed Bragg reflector (DBR) structure via atomic layer deposition or spin-coating, here the 1-6 pairs of magnesium fluoride (MgF 2 )/zinc sulfide (ZnS) alternative dielectric layers were grown via thermal evaporation. The absorption, transmission, reflection, and photoluminescence (PL) spectra were evaluated. 5 pair MgF 2 /ZnS denotes the largest reflectance (88.5% at 535 nm) together with a stopband at 450-650 nm among the 1-6 pair dielectric layers, exhibiting the potential for using as DBR. Relative to the bare 4,4'-bis (carbazol-9-yl)biphenyl(CBP):(4s,6s)−2,4,5,6-tetra(9H-carbazol-9-yl) isophthalonitrile (4CzIPN) film, the PL intensity of CBP:4CzIPN/5 pair MgF 2 /ZnS DBR is enhanced and splitted into two peaks. The 5 pair alternative dielectric film presents more uniform aggregation over 4 pair MgF 2 /ZnS. The cross-sectional scanning electron microscopic image denotes explicit layering for the MgF 2 and ZnS. The organic light-emitting diode (OLED) incorporating 5 pair MgF 2 /ZnS DBR layers illustrates significantly improved electroluminescent (EL) performance due to the photons concentrated in the direction perpendicular to the DBR. The slightly narrowed EL spectrum is originated from the microcavity effect between the two Al electrodes. Here we develop a universal method for the DBR fabrication suitable to most of OLEDs.

To inhibit the light loss of substrate mode at the substrate/air interface in organic light emitting diodes (OLEDs), regular porous polystyrene (PS) template was fabricated via the “Breath figure” method. The structure of porous mold was optimized by adjusting the PS solution concentration from 10 to 60 mg/ml and relative humidity from 60% to 80%. The optimal porous PS mold was achieved at 50 mg/ml PS solution under 70% relative humidity. Then, elastic micro-lens arrays based on transparent elastomer polydimethylsiloxane (PDMS) were obtained via a two-step transferring process from the porous PS mold. The projection experiment exhibits excellent focusing effect of the PDMS convex lens relative to the planar PDMS film. These PDMS micro-lens films were in situ fabricated onto the external face of the red OLED device to extract substrate mode light. By using the PDMS micro-lens array with a height of 1.2 μm and a diameter of 6.7 μm, the OLED device demonstrates an enhancement of 32.7%, 35.6%, 46.5%, and 27.6% for maximum luminance, current efficiency, power efficiency, and external quantum efficiency, respectively, without changing its color purity. The device with PDMS micro-lens exhibits a higher intensity than an ideal Lambertian emission pattern, especially at viewing angles from 30° to 60°. It suggests that the introduction of external micro-lens structure significantly improves the light outcoupling efficiency.