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Carbon nanomaterials are effective conductive fillers for permanent antistatic composites due to their long-term stability in electrical conductivity under ambient temperature and humidity. Where graphene or graphene-like materials have been demonstrated to be the most promising conductive fillers. However, the preparation of graphene and further dispersion into polymer matrices to obtain interconnected conductive networks is still a big challenge for conductive composites. A facile green path (all solid states), microsphere rolling transfer method, has been adopted to introduce nano-graphite conductive fillers for polyethylene. The nano-graphites were well dispersed into polyethylene matrices to give interconnected networks with low loading. The conductivity reinforcements of nano-graphite fillers even overtake those of complicated graphene fillers. The percolation threshold of the conductive composites with nano-graphite fillers for polyethylene has been demonstrated to be as low as 0.85 wt%. The electrical conductivity of the conductive composites was measured to increase by 13 orders of magnitude with 2.05 wt% nano-graphite fillers (0.02 S/m), much higher than traditional solid mixing methods and approaching to the best effects from complicated solution mixing of graphene fillers. The nano-graphite conductive networks are easily adjusted and the method is feasible to almost all conventional solid resins and industrial production. Image 1 [ABSTRACT FROM AUTHOR]

Graphene is one of the most fantastic nanomaterials and has attracted much attention in various fields. The industrial applications are hindered since there is no effective path to produce scalable few layered graphene without functional groups. Here we report a simple effective green path, a soft ball-microsphere rolling transfer process, to produce bulk quantity of few layered graphene without functionalization. The as-produced graphene nanosheets have been demonstrated by height statistics to have 1–10 layers with average layers of 3.8 ± 1.9 and further confirmed by spectroscopic metrics. No functional groups or contamination have been introduced in the processes. No extra time-consuming purification processes are needed. About 70 mg graphene sheets were obtained from one 500 ml agate tank after process carried out at a speed of 100 rpm for 2 h. The exfoliation can be easily extended to industrial scale by using larger and more agate tanks without the sacrifice of yields. Image 1 [ABSTRACT FROM AUTHOR]

This case report describes the induced ankylosis of the primary canines for use as absolute anchorage for maxillary protraction. The patient was a young boy with Class III malocclusion and cleft soft palate. The final occlusion was esthetic, functional, healthy, and stable 4 years after treatment. [ABSTRACT FROM AUTHOR]

Abstract The semiconductor antimony sulfide (Sb 2 S 3) is a potential absorber materials for the top sub-cell of Si-based tandem solar cells because of its appropriate band-gap, simple binary composition, nontoxic elements, and long-term stability. In this study, polycrystalline Sb 2 S 3 films were fabricated by post-annealing of radio frequency (RF) magnetron sputtered precursors using an Sb2S3 target. The effects of the post-annealing temperature and atmosphere on Sb 2 S 3 film properties and device performances were investigated. A high-performance device having a 2.41% power conversion efficiency was obtained by making use of a uniform Sb2S3 absorber layer. This preliminary experimental study shows that Sb2S3 thin films could be used as top sub-cell absorber materials for third-generation high efficiency, stable, and environmentally friendly Sb 2 S 3 /Si tandem solar cells. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Web personalization has been widely adopted in the mobile shopping context to improve shopping experience and consumer loyalty. Timing is a crucial issue of the implementation of web personalization, a topic not yet adequately investigated in the extant literature. Web personalization could classify into two forms, namely Before-search Web Personalization (BSWP) and After-search Web Personalization (ASWP), in the mobile shopping context. Besides, motivations are the critical factors in mobile shopping, and seldom research has studied the effects of motivation on consumer's use of web personalization in the mobile shopping context. To advance understanding of the timing issue of web personalization, this paper employs the Uses and Gratifications method to investigate how mobile shopping motivations influence consumers' use of BSWP and ASWP, respectively. Furthermore, this paper also investigates the role of an important personal disposition (i.e. need for cognition). Empirical results indicate that shopping motivations could have significant effects on web personalization use; furthermore, BSWP use and ASWP use are predicted by different shopping motivations. Besides, need for cognition is found to positively moderate some effects of mobile shopping motivations on web personalization use. Theoretical and practical implications are also discussed. [ABSTRACT FROM AUTHOR]

T helper type 2 (Th2) cytokine-activated M2 macrophages contribute to inflammation resolution and wound healing. This study shows that IL-4-primed macrophages exhibit a stronger response to lipopolysaccharide stimulation while maintaining M2 signature gene expression. Metabolic divergence between canonical M2 and non-canonical proinflammatory-prone M2 (M2 INF) macrophages occurs after the IL-4Rα/Stat6 axis. Glycolysis supports Hif-1α stabilization and proinflammatory phenotype of M2 INF macrophages. Inhibiting glycolysis blunts Hif-1α accumulation and M2 INF phenotype. Wdr5-dependent H3K4me3 mediates the long-lasting effect of IL-4, with Wdr5 knockdown inhibiting M2 INF macrophages. Our results also show that the induction of M2 INF macrophages by IL-4 intraperitoneal injection and transferring of M2 INF macrophages confer a survival advantage against bacterial infection in vivo. In conclusion, our findings highlight the previously neglected non-canonical role of M2 INF macrophages and broaden our understanding of IL-4-mediated physiological changes. These results have immediate implications for how Th2-skewed infections could redirect disease progression in response to pathogen infection. [Display omitted] • Non-canonical M2 INF macrophages show proinflammatory phenotype upon microbial stimulation • Glycolysis supports Hif-1α stabilization in M2 INF macrophages • Wdr5-dependent H3K4me3 modification is integral to M2 INF macrophages • Acute IL-4 exposure elicits M2 INF macrophages in vivo and augments antibacterial response Dang et al. reveal that IL-4 preconditioning generates potent M2 inflammatory macrophages with enhanced proinflammatory potential. Metabolic reprogramming, Hif-1α stabilization, and Wdr5-dependent H3K4me3 modification are factors shaping this phenotype. Acute IL-4 treatment bolsters resistance to bacterial infection, broadening our understanding of IL-4-mediated effects and transforming approaches for Th2-associated inflammatory diseases. [ABSTRACT FROM AUTHOR]

This paper presents optimisation of rear Si texturing by KOH-based solution for enhanced light-trapping in liquid-phase crystallised Si thin-film solar cells on glass. Texturing with 3 µm Si removal exhibits the largest absorption enhancement (compared with 1 and 2 µm Si removal) due to the enhanced light scattering by the rear pyramidal features. In the solar cells with SiO x /SiN x /SiO x buffer layer (with anti-reflection effect), the J sc is found to increase from 20.4 (planar reference) to 22.6 mA/cm 2 (10.8% enhancement) with the optimised rear Si texturing. The V oc and pFF are not degraded. After incorporating white paint back surface reflector and front anti-reflection foil to the rear-textured solar cells, J sc up to 25.4 mA/cm 2 (24.5% relative enhancement) is achieved. [ABSTRACT FROM AUTHOR]

In this research, we present thermal evaporated MoO 3 layer as a primary back contact for pure sulphide Cu 2 ZnSnS 4 solar cells. The effects of incorporating MoO 3 in primary back contact and its thickness on the Cu 2 ZnSnS 4 device performance are investigated. The MoO 3 layer acts as enhancing sodium diffusion site where sodium is more effectively diffused into CZTS absorber, facilitating the formation of larger CZTS grains during sulfurization process compared to the reference absorber. The power conversion efficiency is improved from 5.2% to 6.2% on average, yielding the highest efficiency of 6.52% by the insertion of 10 nm MoO 3 layer between Cu 2 ZnSnS 4 absorber and molybdenum contact. The major efficiency enhancement arises from open circuit voltage which is improved from 530 to 615 mV. [ABSTRACT FROM AUTHOR]

In this work, a novel diode laser annealing was performed as a post-sulfurization heat treatment on pure-sulfide Cu 2 ZnSnS 4 thin film solar cells fabricated by sputtering deposition. The effect on both film quality and device performance after annealing at various laser doses was investigated. After receiving an ultra-fast laser scan treatment, the crystallinity of the CZTS film can be improved and the Cu/Zn disordering is reduced. The power conversion efficiency of the laser annealed device was boosted to 7.33%, compared with the reference cell efficiency of 6.72%. The major increase in the short circuit current is driving force of such improvement, from 18 mA/cm 2 to 19.31 mA/cm 2 after laser treatment. These results indicate that the quality of CZTS thin films and the device performance can be effectively improved by the diode laser annealing. [ABSTRACT FROM AUTHOR]

This paper presents enhanced light-trapping (LT) in liquid-phase crystallised silicon (LPC Si) thin-film solar cells on glass superstrate by optimised back surface reflectors (BSRs). In the LPC Si film on SiO x buffer layer (without anti-reflection effect), the white paint BSR is found to increase the long wavelengths light absorption, with potential short-circuit current density (J sc ) of 23.6 mA/cm 2 (15.7% enhancement, compared to the planar reference film). Ag plasmonic nanoparticles (NPs) reflector with surface coverage of 47.9% and average diameter of 196.3 nm shows almost similar absorption enhancement as the white paint but with slightly lower potential J sc (23.3 mA/cm 2 , or 14.2% enhancement). In the LPC Si solar cells, the average open-circuit voltage (V oc ) and pseudo fill factor (pFF) are not deteriorated by the presence of the Ag NPs on the Si surface. When combining the Ag NPs, white paint and anti-reflection foil, J sc up to 23.3 mA/cm 2 (18.9% enhancement compared to the planar reference cell) is achieved. [ABSTRACT FROM AUTHOR]

Summary B cell CLL/lymphoma 11A (BCL11A) is a transcription factor and regulator of hemoglobin switching that has emerged as a promising therapeutic target for sickle cell disease and thalassemia. In the hematopoietic system, BCL11A is required for B lymphopoiesis, yet its role in other hematopoietic cells, especially hematopoietic stem cells (HSCs) remains elusive. The extensive expression of BCL11A in hematopoiesis implicates context-dependent roles, highlighting the importance of fully characterizing its function as part of ongoing efforts for stem cell therapy and regenerative medicine. Here, we demonstrate that BCL11A is indispensable for normal HSC function. Bcl11a deficiency results in HSC defects, typically observed in the aging hematopoietic system. We find that downregulation of cyclin-dependent kinase 6 ( Cdk6 ), and the ensuing cell-cycle delay, correlate with HSC dysfunction. Our studies define a mechanism for BCL11A in regulation of HSC function and have important implications for the design of therapeutic approaches to targeting BCL11A. [ABSTRACT FROM AUTHOR]

Summary Enhancers are the primary determinants of cell identity, but the regulatory components controlling enhancer turnover during lineage commitment remain largely unknown. Here we compare the enhancer landscape, transcriptional factor occupancy, and transcriptomic changes in human fetal and adult hematopoietic stem/progenitor cells and committed erythroid progenitors. We find that enhancers are modulated pervasively and direct lineage- and stage-specific transcription. GATA2-to-GATA1 switch is prevalent at dynamic enhancers and drives erythroid enhancer commissioning. Examination of lineage-specific enhancers identifies transcription factors and their combinatorial patterns in enhancer turnover. Importantly, by CRISPR/Cas9-mediated genomic editing, we uncover functional hierarchy of constituent enhancers within the SLC25A37 super-enhancer. Despite indistinguishable chromatin features, we reveal through genomic editing the functional diversity of several GATA switch enhancers in which enhancers with opposing functions cooperate to coordinate transcription. Thus, genome-wide enhancer profiling coupled with in situ enhancer editing provide critical insights into the functional complexity of enhancers during development. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of orthodontic expansion on graft area of a tissue-engineered bone (TEB) BMSCs/β-TCP, and to find an alternative strategy for the therapy of alveolar cleft. A unilateral alveolar cleft canine model was established and then treated with BMSCs/β-TCP under rapid maxillary expansion (RME). Sequential fluorescent labeling, radiography and helical computed tomography were used to evaluate new bone formation and mineralization in the graft area. Hematoxylin–eosin staining and Van Gieson׳s picro fuchsin staining were performed for histological and histomorphometric observation. ALP activity, mineralization and the expression of osteogenic differentiation related genes of BMSCs that grew on the β-TCP scaffold were promoted by their cultivation in osteogenic medium. Based on fact, TEB was constructed. After 8 weeks of treatment with BMSCs/β-TCP followed by RME, new bone formation and mineralization of the dogs were markedly accelerated, and bone resorption was significantly reduced, compared with the untreated dogs, or those only treated with autogenous iliac bone. The treatment with both TEB and RME evidently made the bone trabecula more abundant and the area of bone formation larger. What is more, there were no significant differences between BMSCs/β-TCP group and the group treated with autogenous bone and RME. This study further revealed that TEB was not only a feasible clinical approach for patients with alveolar cleft, but also a potential substituent of autogenous bone, and its combination with RME might be an alternative strategy for the therapy of alveolar cleft. [ABSTRACT FROM AUTHOR]

The microstructural properties of polycrystalline silicon films obtained by either solid-phase crystallisation (SPC) or laser-induced liquid-phase crystallisation (LPC) were investigated by transmission electron microscopy (TEM). In SPC films, the most common intra-grain defects are dislocations with the density as high as 1E10 cm −2 determined from cross-sectional weak-beam dark-field images. The highest dislocation density in LPC film is at least two orders of magnitude lower than the SPC film, 1E8 cm −2 and typically it is below 1E6 cm −2 . The most common defect type in LPC films is twin boundaries and other junctions of different coincidence site lattice (CSL) boundaries. Such differences in the material structural properties result in far superior electrical performance of solar cells made of LPC films, such as mobility up to 400 cm 2 V −1 s −1 , similar to c-Si wafers, and the higher open-circuit voltage up to 585 mV. [ABSTRACT FROM AUTHOR]

A silicon nanostructure is fabricated in polycrystalline silicon thin films by metal-assisted wet chemical etching using thermally annealed silver nanoparticles as a catalyst. The Si nanostructure has an ant-nest feature. Solar cells based on the silicon nanostructure gives 90% short-circuit current enhancement compared to the cells based on the planar film. We also report that Al 2 O 3 passivation of the silicon nanostructure provides a new approach to improving the polycrystalline silicon thin film’s electrical property. The open-circuit voltage of the Al 2 O 3 passivated cells is improved by 70 mV. [ABSTRACT FROM AUTHOR]

[Display omitted] • The orthogonal principal component-optimization method for performance enhancement of the diesel engine is proposed. • An improved chemical kinetics mechanism of 134 species and 475 reactions is developed. • Numerical model of diesel engine is simulated and are compared with the experimental results. • Improvement suggestions for performance enhancement of the diesel engine are proposed. In this work, the biodiesel-diesel blending fuels (B20, B30 and B40) and pure diesel fuel (B0) were employed to investigate the effects of intake pressure and EGR ratio on the performance and emission characteristics of diesel engine. The 3D model is developed by the AVL-Fire coupled Chemkin code. In addition, an improved chemical kinetics mechanism of 134 species and 475 reactions is employed to simulate the fuel combustion process. The results show that the improved model improves the calculation accuracy and the high intake pressure and oxygen content in biodiesel are beneficial for the improvements of performance and emission characteristics. However, the NO emission increases. On the contrary, the EGR effectively reduces NO x emission. Finally, the performance and emission characteristics of diesel engine are optimized by the orthogonal principal component-optimization method. Moreover, the NO x mass fraction is reduced by 78.6 % and the engine power is decreased by 5.60%. Therefore, the reasonable parameter is beneficial for alleviating the conflict between performance and emission characteristics of diesel engine. [ABSTRACT FROM AUTHOR]

The urban inland river ecosystems are now facing comprehensive pollution and governance pressures. Up to now, few works related to the multiple pollution assessment of trace metals, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) for the urban inland river sediments have been reported in China. Our study investigated the spatial distribution, ecological risk and potential sources of trace metals, PAHs and PCBs in surface sediment collected from 20 sampling sites of Sanya River, Hainan Province, China. The pollution status and potential ecological risk of trace metals were evaluated using the contamination indexes including geoaccumulation index (I geo), individual potential ecological risk (E r i), potential ecological risk index (RI) and pollution load index (PLI). Considering the carcinogenicity and toxicity of PAHs and PCBs to human health and the ecological environment, we also analyzed the distributions, sources and adverse biological effects of PAHs and PCBs according to the sediment quality guidelines (SQGs), principal component analysis (PCA) and other source analysis. This study revealed that the surface sediments in Sanya River were extremely slight pollution and showed a very low ecological risk according to I geo , E r i , PLI and RI results for trace metals. Besides, PAHs and PCBs pollution detected may not pose considerable adverse biological effect to ecological environment in a foreseeable period on the basis of comprehensive research results. The overall surface sediments quality of the Sanya River not seem to pose a serious pollution and ecological risk based on the evaluation results of multiple pollution factors. The study provided detailed information on the multiple pollution status and location of surface sediments, one of the key environmental indicators of international tourism cities, in the Sanya River, which would be useful for the water quality improvement of Sanya River and the environmental remediation of the other coastal ecosystems from different regions. [Display omitted] • Multiple assessment of comprehensive pollution of sediments in Sanya River, China. • Distribution and sources of trace metals, PAHs and PCBs were studied. • Trace metals, PAHs and PCBs posed a low pollution level and ecological risk. • Study gave the vital references for environmental remediation of coastal ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Properties of heavily boron-doped hydrogenated polycrystalline germanium (Ge) films sputter-deposited on glass are investigated for developing p+ emitters of the bottom cells of low cost monolithic tandem solar cells. The films were deposited and in-situ doped by co-sputtering Ge with boron at various power levels (P B) in a mixture of argon and hydrogen at 500°C, and then followed by a rapid thermal anneal process at 550°C for 120s or 600°C for 60s, respectively. The dependence of the structural properties of the films on the various boron incorporations as well as annealing conditions was explored by Raman and X-ray diffraction measurements. We find that the films as deposited at 500°C are polycrystalline with strong (220) preferential orientation, which are normally of columnar structure, confirmed by cross-sectional transmission electron microscopy. Revealed by Hall measurements, a boron activation level of 6.24×1019 atoms/cm3, well above reported maximum solid solubility in crystalline Ge, was obtained in the as deposited film at P B=55W. Annealing at 600°C enhanced the concentration to 1.21×1020 atoms/cm3. A fact that boron hardly diffuses in Ge at temperatures below 800°C makes the resultant material an excellent candidate for thin p+ emitters of the bottom cells of monolithic tandem solar cells. [ABSTRACT FROM AUTHOR]

• Amount of BpA in its analogues can be determined by THz spectral processing method. • SVR is used to extract obscure properties from THz spectra of complex mixtures. • SVR in combination with THz-TDS can predict sample concentrations with R2 = 0.98. • Machine learning method is a forecast strategy for THz spectroscopic analysis. Quantitative analysis of complex mixtures is a great challenge for spectral analysis. Bisphenol A (BpA) is a chemical predominantly used in manufacturing and is being replaced by other analogs due to its potential toxicity. Reliability methods is hence crucial for identification and quantification of bisphenol mixtures. In this study we present an attractive strategy for composition determination of BpA incorporated in its analogue mixtures. Terahertz spectra of four bisphenol components are analyzed using machine learning method (SVR) to learn the underlying model of the frequency against the target concentration of BpA in mixtures. The learned mode predicts the concentrations of the unknown samples with decision coefficient R2 = 0.98. Absorption spectra for bisphenols mixtures were successfully reconstructed by a hold-out validation scheme. The results indicate the terahertz spectroscopy in combination with SVR is robust and accurate in mixture quantitative analysis and should play a significant role for industrial applications in the future. [ABSTRACT FROM AUTHOR]

The GHGs contributions (tally by carbon emissions) during treatment of domestic food waste and residual waste from pilot communities (contained 2365 families) in Shanghai, China, under different Modes induced by garbage classification were investigated. It was found that under the present condition of garbage classification in Shanghai, 51.8% of the food waste could be separated finally. With garbage classification, the load of landfill was saved by 17.3% (Mode 2) and 16.5% (Mode 3), the moisture of garbage for incineration was reduced by 13.6%, and the lower heating value (LHV) of garbage was increased by 16.2%. Applying the life-cycle assessment (LCA) methodology and Life Cycle Inventory (LCI) with material flows, net carbon emissions during the treatment of garbage were found to be in the following order: Mode 3 (1.60 × 10−3 kg CE/kg waste) < Mode 2 (4.85 × 10−3 kg CE/kg waste) < Mode 1 (4.94 × 10−3 kg CE/kg waste) < landfill (1.49 × 10−2 kg CE/kg waste). Mode 2 and Mode 3 were replaceable patterns of Mode 1, and anaerobic digestion was the recommendable strategy to recover energy from food waste. Especially, there was no obvious benefit of increasing the separation proportion of food waste to 60% (or above) for reducing net carbon emissions in the following treatment processes. Unlabelled Image • 51.8% of food waste could be separated after garbage classification in Shanghai. • Landfill load was saved by about 17% in disposal modes with garbage classification. • Net carbon emission: Mode 3 < Mode 2 < Mode 1 < landfill • Modes 2 and 3 were replaceable patterns of Mode 1. • Anaerobic digestion was a recommendable strategy to recovery energy from food waste. [ABSTRACT FROM AUTHOR]

In this work we report the Na incorporation from Na-doped Mo (Mo-Na) back contact for kesterite Cu 2 ZnSnS 4 solar cells on flexible stainless steel substrates. It is demonstrated that Na can be effectively incorporated into CZTS by inserting Mo-Na layer at back contact. Direct contact of CZTS and Mo-Na layer leads to poor homogeneity and adhesion. The thickness of MoS 2 formed at the back contact depends on the presence of Na and whether Mo contacts with CZTS directly. Back contact configuration with a Mo capping layer on Mo-Na layer is found to be helpful to maintain the advantages of Mo back contact and control the thickness of MoS 2 interface. As a result, CZTS device fabricated on this configuration yields higher conversion efficiency of 6.2%. However, this efficiency is still far lower than that on traditional soda lime glass substrate which shows efficiency over 8%. The loss mechanism of device fabricated on stainless steel is investigated and analyzed according to the device performance and electrical parameters. [ABSTRACT FROM AUTHOR]

• Multisource sludge properties were first fully reported in the Yangtze River basin. • Exhaustive data on multisource sludge occurrence was made comprehensively available. • The origins of heavy metals and POPs were correlated among multisource sludge. • Multisource sludge co-treatment and disposal scenarios were systematically proposed. Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including Jiujiang, Wuhu, Lu'an, Zhenjiang and Wuhan, this study investigated and summarized the characteristic variations and distribution differences of multiple indicators and substances from municipal sludge, dredged sludge, and river and lake sediments. The results demonstrated pH of multisource sludge was relatively stable in the neutral range. Organic matter and water content among municipal sludge were high and varied considerably between different wastewater treatment plants. Dredged sludge had an obviously higher sand content and wider particle distribution, which could be considered for graded utilization depending on its size. The nutrients composition of river and lake sediments was usually stable and special, with lower nitrogen and phosphorus content but higher potassium levels. The sources of heavy metals and persistent organic pollutants in multisource sludge were correlated, generally much higher among municipal sludge than dredged sludge and river and lake sediments, which were the most important limitation for final land utilization. Despite various properties of multisource sludge, the final fate and destination have some overall similarities, which need to be supplemented and improved by standards and laws. The study provided a preliminary analysis of suitable technical routes for municipal sludge, dredged sludge, river and lake sediments based on their different characteristics respectively, which was of great significance for multisource sludge co-treatment and disposal in the future of China. [Display omitted] [ABSTRACT FROM AUTHOR]

Single crystalline Ge-rich Si x Ge 1-x epitaxially grown on a Si substrate is attracting great attention for its potential in optical and electronic device applications. One method of achieving Si x Ge 1-x epitaxy is by aluminium-assisted crystallization although the challenge of controlling the Si content in the Si x Ge 1-x is limited by the furnace annealing process. Herein, we report the use of a diode laser to induce aluminium-assisted crystallization of Si x Ge 1-x on Si with minimal Si content in the Si x Ge 1-x layer. By replacing furnace heat treatment with laser treatment, the reaction time is shortened from minutes to milliseconds which can limit the amount of Si incorporation into the Si x Ge 1-x films. X-ray diffraction, Raman spectroscopy, transmission electron microscopy and X-ray spectroscopy analyses are conducted on the fabricated films revealing the achievement of Ge-rich Si x Ge 1-x on Si through laser-induced aluminium-assisted crystallization. The higher laser dose may slightly increase the Si content and improve the crystallinity of the Si x Ge 1-x films. • First use of laser to induce aluminium-assisted crystallization of Si x Ge 1-x on Si • The laser-induced method reduces the reaction time from minutes to milliseconds • Achievement of Ge-rich Si x Ge 1-x on Si by this laser-induced method • Higher laser dose may improve the crystallinity of Si x Ge 1-x films [ABSTRACT FROM AUTHOR]

In this work, epitaxial Ge films grown on Si by magnetron sputtering were annealed by diode laser as a replacement for conventional thermal annealing to reduce the threading dislocation density (TDD). After laser scans of millisecond exposure time, improvement of crystallinity and increase in tensile strain are observed in the Ge films. TDD of the Ge film is reduced by two orders of magnitude from 10 10 cm − 2 to 10 8 cm − 2 after only three laser scans. Diode laser annealing is a fast and low-cost method to effectively reduce TDD in epitaxial Ge films on Si. [ABSTRACT FROM AUTHOR]

Graphene/transition metal oxide composites combine the energy-storing mechanisms of pseudo-capacitance and double layer capacitance, and are considered as preferred electrode materials for supercapacitors. For the composites' complex structure and components, it is important to develop a method with good controllability to monitor the structure and component of the nanocomposites, which is critical for the electrochemical performance optimization and the further industrial application. In this paper, graphene oxide (GO) and nickel acetate tetrahydrate (Ni(CH 3 COO) 2 ·4H 2 O) were used to prepare reduced graphene oxide/nickel oxide (rGO/NiO) nanocomposites utilizing dielectric barrier discharge (DBD) plasmas with AC and nanosecond (ns) pulse power supplies. The scanning electron microscope (SEM), Raman spectra, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) are used to study the nanocomposites created under various discharge conditions. It shows the splitting and delamination of the prepared composites surface, a rise in ID/IG, and the reduction of GO after plasma treatment result in an excellent connection with the electrode material surface and electrolytic solution, and good capacitor performance. The rGO/NiO nanocomposites prepared by AC DBD have better charge transfer resistance, conductivity, and electrochemical capacitance retention rate than the materials prepared by ns pulsed DBD, which is analysed by power deposition and thermodynamics. The work contributes to reveal the mechanism of plasma material preparation, which will give new impetus to the development of environmental-friendly method for electrode materials preparation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Phosphorus structures are promising anode materials for lithium and sodium ion batteries. However, the cycle stability is a big challenge for most phosphorus anode materials due to pulverization. Black phosphorus has been demonstrated to have extremely high stability as anodes due to its layered features. Black phosphorus have been in situ grown to wrap hierarchical phosphorus hybrids with multi-walled carbon nanotubes (MWCNTs) veins. The electrochemical performances of the hierarchical phosphorus hybrids have been significantly enhanced due to the black phosphorus skins and wrapped amorphous and fibrous phosphorus. Extremely high cycle stability and high specific capacitiyes have been achieved by the new hierarchical phosphorus hybrids. A specific capacity of 560 mAh g−1 has been still obtained at a current rate of 500 mA g−1 after 250 cycles. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

We report the fabrication of epoxy-based composites using well-designed core/shell Si/SiO 2 (denoted as Si*) and core/shell/shell structured Si/SiO 2 /Polydopamine (denoted as Si*@PDA) particles as fillers, which exhibit improved dielectric properties and thermal conductivity. Using the core-shell Si* and Si*@PDA particles as fillers in the epoxy-based composites, the dielectric loss tangent is remarkably suppressed and the volume resistivity is apparently enhanced, as compared with that using raw Si particles as fillers. Moreover, the Si*@PDA composites have higher dielectric constant and lower loss tangent. For instance, the dielectric constant of Si*@PDA/epoxy composite with 33.8 vol% filler content is up to 19.8 at room temperature at 100 Hz, which is nearly 5.3 times of that of the pure epoxy polymer (3.4), while its loss tangent is only 0.085. Additionally, the core-shell particle-based composites still possess a high thermal conductivity. [ABSTRACT FROM AUTHOR]

Low Voc is the major factor limiting the current efficiency of pure sulfide Cu 2 ZnSnS 4 (CZTS) thin film solar cells. In this work, stacking two CZTS layers with different majority doping levels is employed to increase Voc. With this double-layer structure, the obtained highest efficiency is 7.57% with Voc of 734 mV, Jsc of 15.4 mA/cm 2 and FF of 67.0%. Compared to the traditional device with single CZTS layer (Efficiency: 7.62%, Voc: 665 mV, Jsc: 20.0 mA/cm 2 , FF: 57.3%), the average Voc has been increased by 70–80 mV. However the Jsc was decreased due to voids within the CZTS and severe band tailing problem, limiting the further boost of efficiency for double-layer CZTS solar cell. [ABSTRACT FROM AUTHOR]

In this work we perform comprehensive characterization on a 6.9% pure sulphide Cu 2 ZnSnS 4 (CZTS) device and construct a 2D device model in Sentaurus TCAD to identify possible roots of performance bottlenecks. Electrical and optical parameters of the absorber from comprehensive electrical and optical characterization, together with other necessary parameters from literature, we successfully reproduce measured current density-voltage (J-V) and external quantum efficiency (EQE) curves. Absorption coefficient is extracted by fitting measured internal quantum efficiency (IQE). At the buffer/absorber interface, a surface recombination velocity of 1×10 5 cm/s is identified to adequately describe measured spectral response at the near-interface region. Furthermore, a bulk lifetime of ~29 ns is extracted from effective lifetime modelling in conjunction with time resolved photoluminescence (TRPL) results. The key underlying V oc deficit, ~200 mV, is pinpointed to bandgap fluctuation, which is backed by the simulation study on both QE tail and steady state photoluminescence. [ABSTRACT FROM AUTHOR]

Kesterite Cu 2 ZnSnS 4 (CZTS) thin film solar cells are fabricated based on sputtering and post sulfurization process on stainless steel substrates. NaF layers with different thickness are used as external sodium source to address the lack of Na issue in Na-free steel substrates and 10 nm of NaF layer is proved to be the optimal thickness. Sodium incorporation into CZTS induces the metal element redistribution, facilitates CZTS film recrystallization and promotes the phase evolution. Appropriate amount of sodium is evidenced to yield an enhancement in power conversion efficiency from 3.07% to 4.10% whilst further increase in sodium tends to deteriorate the device efficiency. Device performance deterioration is correlated to the rather small grain size accompanied with a large amount of grain boundaries and unfavorable SnS 2 secondary phase for CZTS samples without sodium, while pinholes and lower carrier density in absorber for CZTS samples with over amount of sodium. [ABSTRACT FROM AUTHOR]

Spinal cord development is precisely orchestrated by spatiotemporal gene regulatory programs. However, the underlying epigenetic mechanisms remain largely elusive. Here, we profiled single-cell chromatin accessibility landscapes in mouse neural tubes spanning embryonic days 9.5–13.5. We identified neuronal-cell-cluster-specific cis -regulatory elements in neural progenitors and neurons. Furthermore, we applied a novel computational method, eNet, to build enhancer networks by integrating single-cell chromatin accessibility and gene expression data and identify the hub enhancers within enhancer networks. It was experimentally validated in vivo for Atoh1 that knockout of the hub enhancers, but not the non-hub enhancers, markedly decreased Atoh1 expression and reduced dp1/dI1 cells. Together, our work provides insights into the epigenetic regulation of spinal cord development and a proof-of-concept demonstration of enhancer networks as a general mechanism in transcriptional regulation. [Display omitted] • Single-cell chromatin accessibility profiling charts mouse spinal cord development • Enhancer networks control master regulators during neuronal development • Network hub enhancers are potentially key cis- elements to control gene expression • In vivo Atoh1 enhancer knockout demonstrates functional hierarchy of enhancer network Shu and Hong et al. provide single-cell chromatin accessibility analyses of developing mouse spinal cord and identify cis -regulatory elements and regulators for neural cells. Using these data, they define enhancer networks controlling master regulators during spinal cord development and experimentally validate Atoh1 enhancers through in vivo perturbation as a proof of concept. [ABSTRACT FROM AUTHOR]

[Display omitted] • DBD plasma treatment applied to the surface modification of large-scale polymer PET with high efficiency and no pollution product. • New structure of air DBD plasma for large-scale polymer treatment. • Optimized plasma treatment by DBD electrode design and processing regulation. • Molecular simulation revealing the saturation of the hydrophilicity modification for polymer surface. Low surface energy and poor hydrophilicity of the polymer film reduces its working stability and service life in various application fields, but the industrial surface modification for the large-scale film requires the dynamic and efficient processing techniques with the uniform treatment effects. In this study, an efficient air dielectric barrier discharge (DBD) tube electrode array for large-scale polyethylene glycol terephthalate (PET) film treatment was established, and its discharge characteristics and treatment effects were further investigated by experiment and simulation at a microscopic scale. It shows that the increase in the number of electrodes and the applied voltage leads to diffuse and uniform discharge with strong luminous intensity, where the emission spectra is dominated by the second positive band of nitrogen molecules. Moreover, the increase in applied voltage and the decrease in treatment speed both enhance the surface hydrophilicity and the modification uniformity, which is caused by the rough surface and the introduction of oxygen-containing groups by the air DBD treatment. Combined with quantum chemistry calculations, it is speculated that the further modification reaches saturation with particles (COOH group) that causes hydrophilicity. It reveals that the introduction of OH groups on PET surface accounts for the increase in the molecular dipole moment and hydrophilicity; by contrast, the COOH group issued from the further oxidation of OH group decreases the molecular polarity, thereby causing the saturation of particles which causes the hydrophilicity by the air DBD treatment. [ABSTRACT FROM AUTHOR]