The foam stability of oil–water emulsions stabilised by various surface-active components at high temperature is one of the major problems facing foam-flooding petroleum recovery because of foam ...instability at the high temperature underground. In this paper, foams stabilised by sodium dodecylbenzene sulfonate (SDBS), polyethylene glycol (PEG) and silica (SiO2) nanoparticles in water–liquid paraffin (50%/50%) emulsions at temperature from 20 to 80°C were studied. Foam properties such as foam stability over time at different temperatures, equilibrium surface tension, and bubble morphology (bubble size) were determined by surface tension measurements and inverted fluorescence microscopy. High foam stability was demonstrated by emulsions of SDBS, PEG, SiO2 nanoparticles, and liquid paraffin from 40 to 80°C. The properties of the PEG–SDBS foams improved when SiO2 nanoparticles were added. Foam stability increased when SDBS was adsorbed on the bubble surface as the bubbles did not rupture easily in the liquid phase in the presence of SDBS because of the formation of closely packed small bubble droplets bridging between neighbouring large bubbles, which were separated by long chain polymers. This phenomenon may arise because the SiO2 nanoparticles formed networks and were adsorbed with surfactant molecules on the bubble surface of the oil–water emulsion, causing the foam inflexibility to increase and thus improving aqueous foam stability at high temperature.
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•Foam stability of sodium dodecylbenzene sulfonate in the presence of water–paraffin oil is investigated.•The effects of silica nanoparticles and polymers (PEG-600, 1000, and 2000) on foam stability are examined.•Surfactant and polymers interact strongly in the water–liquid paraffin emulsions.•Polymer chain length affects its interactions with surfactant and nanoparticles in foams.•Bridges of small bubble droplets and a three-dimensional network of SiO2 nanoparticles increase foam stability.
Interfacial engineering plays an important role on determining the charge extraction and recombination in organic solar cells (OSCs). In this paper, the performance of OSCs was improved by ...incorporating alkali metal salts into the ZnO electron transport layer (ETL). Under the optimal alkali salt concentration and film preparation condition, the power conversion efficiency of PTB7:PC71BM based device was enhanced from 7.581% to 9.074%, accounting for a 20% increase. Additionally, ZnO ETL doped with alkali metal salts can effectively improve light absorption, electron transport and extraction as well as the better interface contact between ETL and active layer, so as to achieve large short-circuit current density, fill factor, and small series resistance, respectively. This study provides a facile and low cost method to enhance efficiency of OSCs.
Display omitted Alkali metal salts are incorporated into ZnO electron transporting layer to improve optical and electrical properties for organic solar cells.
•The alkali salts doped ETLs is simplistic, low cost, and suitable for mass production.•The alkali salts doped ETLs reduce the interfacial defects and improve contact.•The alkali doped ETL can enhance the electron extraction by decreasing the injection barrier.•The light absorption of active layer based on doped ETL is also enhanced.
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•Turbulent flow in particle classifiers with three rotary cages was investigated using Q criterion.•Formation process and distribution of the vortices were intuitively exhibited.•The ...unwanted large-scale columnar vortex is eliminated by extending the guide cone.•The optimized guide cone significantly increases the Newton efficiency of the classifier.
The particle classifiers with three rotary cages have significant advantage in powder handling capacity. The flow field inside the classifiers were investigated from the perspective of vortex using Q criterion. Formation process and distribution of the vortices were intuitively exhibited. Structure of the guide cone was further optimized, and the classifying performance of the classifiers was evaluated. The results show that complex vortex structures were formed inside the classifier. The large-scale columnar vortex under the guide cone oscillates irregularly. This unwanted vortex is eliminated by extending the guide cone. The structure of the guide cone has little effect on the cut size, but the optimized guide cone with the long cylinder and cone significantly enhances the separation degree of the fine and coarse particles. The classifier obtains finer silica powder with a median size of 2.5 μm and higher Newton efficiency about 71.5%.
Overcoming thermal quenching is generally essential for the practical application of luminescent materials. It has been recently found that frameworks with negative thermal expansion (NTE) could be a ...promising candidate to engineer unconventional luminescence thermal enhancement. However, the mechanism through which luminescence thermal enhancement can be well tuned remains an open issue. In this work, enabled by altering ligands in a series of UiO-66 derived Eu-based metal-organic frameworks, it was revealed that the changes in the thermal expansion are closely related to luminescence thermal enhancement. The NTE of the aromatic ring part favors luminescence thermal enhancement, while contraction of the carboxylic acid part plays the opposite role. Modulation of functional groups in ligands can change the thermal vibration of aromatic rings and then achieve luminescence thermal enhancement in a wide temperature window. Our findings pave the way to manipulate the NTE and luminescence thermal enhancement based on ligand engineering.
Modulation of negative thermal expansion using ligand engineering to achieve an increased temperature range of luminescence thermal enhancement in Eu-based metal-organic frameworks.
See Guerrini and Mei (doi:10.1093/brain/awy196) for a scientific commentary on this article.
Familial cortical myoclonic tremor with epilepsy is an autosomal dominant neurodegenerative disease. Cen ...et al. identify the probable causative mutation by showing that an intronic pentanucleotide (TTTCA)n insertion in SAMD12 co-segregates with the disease in 18 Chinese pedigrees.
Abstract
Familial cortical myoclonic tremor with epilepsy is an autosomal dominant neurodegenerative disease, characterized by cortical tremor and epileptic seizures. Although four subtypes (types 1-4) mapped on different chromosomes (8q24, 2p11.1-q12.2, 5p15.31-p15.1 and 3q26.32-3q28) have been reported, the causative gene has not yet been identified. Here, we report the genetic study in a cohort of 20 Chinese pedigrees with familial cortical myoclonic tremor with epilepsy. Linkage and haplotype analysis in 11 pedigrees revealed maximum two-point logarithm of the odds (LOD) scores from 1.64 to 3.77 (LOD scores in five pedigrees were >3.0) in chromosomal region 8q24 and narrowed the candidate region to an interval of 4.9 Mb. Using whole-genome sequencing, long-range polymerase chain reaction and repeat-primed polymerase chain reaction, we identified an intronic pentanucleotide (TTTCA)n insertion in the SAMD12 gene as the cause, which co-segregated with the disease among the 11 pedigrees mapped on 8q24 and additional seven unmapped pedigrees. Only two pedigrees did not contain the (TTTCA)n insertion. Repeat-primed polymerase chain reaction revealed that the sizes of (TTTCA)n insertion in all affected members were larger than 105 repeats. The same pentanucleotide insertion (ATTTCATTTC)58 has been reported to form RNA foci resulting in neurotoxicity in spinocerebellar ataxia type 37, which suggests the similar pathogenic process in familial cortical myoclonic tremor with epilepsy type 1.
Herein, we report a facile way to incorporate polyethylenimine (PEI) into a mixed BHJ solution of polyN-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadizole) (PCDTBT) ...and 6,6-phenyl C71-butyric acid methyl ester (PC71BM) to fabricate the simplified PSCs. The amine-containing PEI spontaneously migrated into the cathode buffer layer surface by one-step solution processing and thereby formed an ultrathin modification layer between the TiO2 and the active layer. The PEI additive are able to accumulate on the cathode buffer layer surface prior to the PCDTBT and PC71BM during spin-coating, because the amino of PEI can form hydrogen bonds with the hydroxyl groups on the TiO2 surface. By optimizing the doping concentration of PEI in the BHJ, the maximum PCE of 7.22% was achieved for the PCDTBT:PC71BM based device, leading to a 19.9% enhancement compared to the control device. The self-assembled PEI layer substantially reduces the work function and eliminates surface defects of TiO2, thereby significantly minimizing the electron extraction barrier and trap-assisted recombination. This work offers a new guidance to further enhance PSCs performance by using a simple and convenient interface engineering, which demonstrates a huge potential for application in large-scale fabrication.
In this paper, we propose an event-triggered distributed sequential fusion estimator based on information filters. This algorithm not only uses the distributed parallel structure on sensors, but also ...uses the real-time processing of sequential fusion on state estimates. Therefore, it has the advantages of reliability and reduced computational burden. The event-triggered mechanism is designed based on observations of each sensor. Moreover, the equivalence on estimation accuracy of the proposed event-triggered distributed sequential fusion filter and event-triggered centralized fusion filter is proven. A simulation example shows the effectiveness of the proposed algorithm.
Autism spectrum disorder (ASD) represents a set of complex neurodevelopmental disorders with large degrees of heritability and heterogeneity. We sequenced 136 microcephaly or macrocephaly ...(Mic-Mac)-related genes and 158 possible ASD-risk genes in 536 Chinese ASD probands and detected 22 damaging de novo mutations (DNMs) in 20 genes, including CHD8 and SCN2A, with recurrent events. Nine of the 20 genes were previously reported to harbor DNMs in ASD patients from other populations, while 11 of them were first identified in present study. We combined genetic variations of the 294 sequenced genes from publicly available whole-exome or whole-genome sequencing studies (4167 probands plus 1786 controls) with our Chinese population (536 cases plus 1457 controls) to optimize the power of candidate-gene prioritization. As a result, we prioritized 67 ASD-candidate genes that exhibited significantly higher probabilities of haploinsufficiency and genic intolerance, and significantly interacted and co-expressed with each another, as well as other known ASD-risk genes. Probands with DNMs or rare inherited mutations in the 67 candidate genes exhibited significantly lower intelligence quotients, supporting their strong functional impact. In addition, we prioritized 39 ASD-related Mic-Mac-risk genes, and showed their interaction and co-expression in a functional network that converged on chromatin remodeling, synapse transmission and cell cycle progression. Genes within the three functional subnetworks exhibited distinct and recognizable spatiotemporal-expression patterns in human brains and laminar-expression profiles in the developing neocortex, highlighting their important roles in brain development. Our results indicate some of Mic-Mac-risk genes are involved in ASD.
The phase separation of donor and acceptor in bulk-heterojunction plays an important role on the exciton dissociation and charge carrier transport, which decides the performance of organic solar ...cells (OSCs). In this paper, the thin 6,6-Phenyl-C71-butyric acid methyl ester (PC71BM) layer was incorporated as interlayer between active layer and the polyethylenemine electron transport layer of OSCs to realize high efficiency. Both a high short-circuit current density and fill factor were achieved, resulting in a power conversion efficiency up to 9.17% for the optimal device. The incorporation of PC71BM layer not only induced vertical phase separation of active layer to improve exciton dissociation and charge transfer but also modified surface morphology to increase light absorption of the active layer. This study offers a simple and lost cost strategy to improve performance of OSCs.
•Composite electron transport layer is low cost and easy preparation.•Incorporating fullerene derivative layer can reduce the interfacial defects.•The composite buffer layer can improve the phase separation of active layer.•The light absorption and electron extraction are both improved.
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