Film-through large perovskite grains formation via a combination of sequential thermal and solvent treatment

Organic–inorganic halide perovskites have recently attracted strong research interest for fabrication of high-performance, lowcost photovoltaic devices. Recently, we reported a highly reproducible procedure to fabricate high-performance organic–inorganic halide perovskite solar cells. This procedure, based on a onestep, solvent-induced, fast deposition-crystallization method, involves the use of sec-butyl alcohol as a new solvent to induce the CH3NH3PbI3 fast crystallization deposition. In the present study, we propose a reproducible fabrication method to prepare both flat and large-grain perovskite film by adding a pre-annealing step to strengthen the perovskite nucleation, aiming to facilitate the excess CH3NH3I and solvent removal in the sec-butyl alcohol soaking process, in which all films with thickness between 420 nm and 1µm performed uniformly. The best performing planar device obtained with this procedure had an efficiency of 17.2% under AM 1.5G illumination and an average power conversion efficiency of 16.2 ± 0.5%. We also analyzed the efficiency of halide perovskite planar solar cells as a function of the perovskite film thickness; the efficiency dropped only slightly to 15.7% when the perovskite film thickness was increased to 1µm

Fabrication of color tunable organic light-emitting diodes by an alignment free mask patterning method

An alignment free mask patterning method has been proposed for fabricating the side-by-side color tunable organic light-emitting diodes (OLEDs). The demonstrated color tunable OLEDs consists of blue sub-OLEDs and inverted orange sub-OLEDs; both color sub-OLEDs share the same electrodes. With time sequential pulse driving, the blue sub-OLEDs and the inverted orange sub-OLEDs are alternately turned on. Tunable color, resulting from the mixing of the blue and the orange emission, has been realized by simply varying the amplitude ratio of the positive and negative pulses. (C) 2013 Elsevier B.V. All rights reserved

Pore-Scale Flow Effects on Solute Transport in Turbulent Channel Flows Over Porous Media

© 2021, The Author(s), under exclusive licence to Springer Nature B.V.Abstract: Solute transport and mixing at channel-flow–porous media interfaces are strongly influenced by velocity and turbulence structures near porous media, and such coupled channel-flow–porous media systems are commonly observed in nature. However, the effects of pore-scale flows on solute transport in the coupled systems are currently unclear. In this study, we combine particle image velocimetry experiments and large eddy simulations to resolve the pore-scale flow characteristics over and within a porous bed. Then, we perform solute transport simulations by coupling the pore-scale flow fields with a particle-tracking model and show that the pore-scale flows inherent to porous media structure control solute transport. Pore-scale flow properties such as preferential downward–upward flows and vortices occurring near the channel-flow–porous media interface are shown to exert dominant control over interfacial mass exchange and solute transport. To clarify the effects of pore-scale flows on reach-scale transport, we conduct macroscale transport modeling with a spatially averaged stream-wise velocity profile. Because the profile-based model does not incorporate important pore-scale flow features, it significantly overestimates mass transfer into the porous bed, thereby exacerbating late-time tailings in breakthrough curves. Finally, a spatial Markov model, a type of upscaled stochastic transport model, is shown to effectively capture the pore-scale interfacial transport mechanisms via a velocity transition matrix. Our findings confirm that solute transport through channel-flow–porous media interfaces is controlled not only by interfacial turbulent-mixing profiles but also by detailed pore-scale flow structures. Article Highlights: We demonstrate the effects of pore-scale flows on solute transport in coupled turbulent channel-flow–porous media systemsPore structure near the interface exerts dominant control over interfacial mass exchange and solute transportSpatial Markov model effectively upscales the effects of pore-scale flows on solute transport.N

First molecular detection and characterization of Marek’s disease virus in red-crowned cranes (Grus japonensis): a case report

Abstract Background Marek’s disease virus (MDV) resides in the genus Mardivirus in the family Herpesviridae. MDV is a highly contagious virus that can cause neurological lesions, lymphocytic proliferation, immune suppression, and death in avian species, including Galliformes (chickens, quails, partridges, and pheasants), Strigiformes (owls), Anseriformes (ducks, geese, and swans), and Falconiformes (kestrels). Case presentation In 2015, two red-crowned cranes died in Nanjing (Jiangsu, China). It was determined that the birds were infected with Marek’s disease virus by histopathological examination, polymerase chain reaction (PCR), gene sequencing and sequence analysis of tissue samples from two cranes. Gross lesions included diffuse nodules in the skin, muscle, liver, spleen, kidney, gizzard and heart, along with liver enlargement and gizzard mucosa hemorrhage. Histopathological assay showed that infiltrative lymphocytes and mitotic figures existed in liver and heart. The presence of MDV was confirmed by PCR. The sequence analysis of the Meq gene showed 100% identity with Md5, while the VP22 gene showed the highest homology with CVI988. Furthermore, the phylogenetic analysis of the VP22 and Meq genes suggested that the MDV (from cranes) belongs to MDV serotype 1. Conclusion We describe the first molecular detection of Marek’s disease in red-crowned cranes based on the findings previously described. To our knowledge, this is also the first molecular identification of Marek’s disease virus in the order Gruiformes and represents detection of a novel MDV strain