•The ways to modulate electronic structure of g-C3N4 are discussed.•The photocatalytic to photoelectronic applications of g-C3N4 are summarized.•We discuss the pathways to improve photocatalytic and ...photoelectronic properties.•The correlation of electronic structure and photoelectronic properties is founded.
As an analog of graphite, graphitic carbon nitride (g-C3N4) has been the hotspot in the materials science for its unique electronic structure. With medium band gap as well as thermal and chemical stability in ambient environment, it becomes one of the most promising photocatalytic materials. Intensive investigation has been focus on its photocatalytic performance for various reactions to date. What is more, controllable modulation of its electronic structure via doping or chemical functionalization is available. In addition, considerable attention has been paid on its photoelectronic application, such as light emitting device, photocathode, optical sensor, etc. Based on the electronic properties and pathway to modulate its electronic structure, in this review, we highlight the applications of g-C3N4 ranging from photocatalytic to photoelectronic materials.
Graphite like C3N4 (g-C3N4) was synthesized facilely via the low temperature thermal condensation of melamine between 300-650°C. The results showed that the products maintained as melamine when the ...temperature is below 300°C. With the increase of temperature, the products were transformed into carbon nitride and amorphous g-C3N4 successively. The morphology of products was changed from spherical nanoparticles of melamine into layer carbon nitride and g-C3N4 with the increase of temperature. The photoluminescence spectra showed that the carbon nitride products have continuous tunable photoluminescence properties in the visible region with increasing temperature. With the help of steady state, transient state time-resolved photoluminescence spectra and Raman microstructural characterization, a novel tunable photoluminescence mechanism was founded systematically, which is mainly related to the two dimensional π-conjugated polymeric network and the lone pair of the carbon nitride.
Since its inception, the frequency diverse array (FDA) has attracted extensive attention and research because of its unique properties. However, most of the research primarily focuses on linear ...geometry FDA, with fewer studies on planar FDA. This letter proposes a design method based on planar rectangular FDA (PRFDA), which adjusts the frequency of each array element nonlinearly so that the beam direction of planar rectangular FDA can change linearly or nonlinearly with time, forming the desired transmit beampattern. Theoretical analysis and simulation results verify the effectiveness of the proposed method.
We begin by deriving the precise transmit beampattern for the PRFDA and analyzing the impact of its diverse frequency offset settings on beam direction. Building on this groundwork, we propose a DM method rooted in the PRFDA framework, facilitating linear or nonlinear scanning of its beam across three‐dimensional space.
Power battery is one of the core components of electric vehicles (EVs) and a major contributor to the environmental impact of EVs, and reducing their environmental emissions can help enhance the ...sustainability of electric vehicles. Based on the principle of stiffness equivalence, the steel case of the power cell is replaced with lightweight materials, a life cycle model is established with the help of GaBi software, and its environmental impact is evaluated using the CML2001 method. The results can be summarized as follows: (1) Based on the four environmental impact categories of GWP, AP, ADP (f), and HTP, which are the global warming potential (GWP), acidification potential (AP), abiotic depletion potential (ADP (f)) and human toxicity potential (HTP), the environmental impact of lightweight materials is lower than that of the steel box. Among them, the aluminum alloy box has the largest reduction, and the Carbon Fiber Sheet Molding Compound (CF-SMC) box is the second. (2) In the sensitivity analysis of electric structure, an aluminum alloy box is still the most preferable choice for environmental impact. (3) In the sensitivity analysis of driving mileage, the aluminum alloy box body is also the best choice for vehicle life. (4) Quantitative assessment using substitution factors measures the decrease in greenhouse gas emissions following the substitution of steel battery box with lightweight materials. The adoption of aluminum alloy battery box can lead to a reduction of 1.55 tons of greenhouse gas emissions, with a substitution factor of 1.55 tC sb
. In the case that composite materials have not been recycled commercially on a large scale, aluminum alloy is still one of the best materials for the integrated environmental impact of the whole life cycle of the battery boxes.
Abstract
We present the results of a search in LIGO O2 public data for continuous gravitational waves from the neutron star in the low-mass X-ray binary Scorpius X-1. We search for signals with ≈ ...constant frequency in the range 40–180 Hz. Thanks to the efficiency of our search pipeline we can use a long coherence time and achieve unprecedented sensitivity, significantly improving on existing results. This is the first search that has been able to probe gravitational wave amplitudes that could balance the accretion torque at the neutron star radius. Our search excludes emission at this level between 67.5 and 131.5 Hz, for an inclination angle 44° ± 6° derived from radio observations, and assuming that the spin axis is perpendicular to the orbital plane. If the torque arm is ≈26 km—a conservative estimate of the Alfvén radius—our results are more constraining than the indirect limit across the band. This allows us to exclude certain mass–radius combinations and to place upper limits on the strength of the star’s magnetic field with a different probe than ever used before. We also correct a mistake that appears in the literature in the equation that gives the gravitational wave amplitude at the torque balance and we re-interpret the associated latest LIGO/Virgo results in light of this.
In recent years, connected automated vehicles (CAVs) have attracted much attention, and the coordination strategy of CAVs in isolated intersections has been widely discussed. However, these ...algorithms for isolated intersections cannot be directly applied in a multi-intersection road network (MiRN). The coordination strategy in the MiRN requires further investigation. This paper proposes a two-tier strategy for CAV coordination in the MiRN. First, we analyze the coordination problem in isolated intersections and formulate it as a mixed-integer programming problem. Then, for the MiRN, we propose a consensus prediction method to estimate the travel time for CAVs with different paths. Finally, a novel coordination approach is given, showing how to determine the optimal path for CAVs. The experimental results demonstrate the efficiency of the proposed strategy under various traffic flow rates. Compared with the fixed signal time assignment method and the actuated signal time assignment method, our method reduces the average travel time by about 74–83% under different flow rates. We also evaluate the impact of parameters on the strategy’s performance and provide some suggestions for setting these parameters.
The additive manufacturing technique of micro-stereolithography (µSL) is applied to fabricate alkaline niobate (K0.48Na0.52NbO3, KNN) based lead-free piezoceramics. Complex KNN-based piezoceramic ...green parts with fine dimensional characteristics, such as a piezoceramic transducer array and a hollow hemisphere, have been printed. The two-step debinding and sintering processes are employed to obtain crack-free dense KNN ceramics with complex shapes. These printed KNN ceramics exhibit superior piezoelectric and ferroelectric performance (εr = 2150, d33 = 170 pC/N, Pr = 12.1 μC/cm2, EC = 6.1 kV/cm, and TC = 230 °C), which are comparable to those of KNN piezoceramics made by traditional methods. These results suggest that the µSL technique may serve as an alternative method to manufacture KNN lead-free piezoceramic components, especially for the application with complex architectures.
In order to assess potential associations between autism spectrum disorder (ASD) phenotype, functional GI disorders and fecal microbiota, we recruited simplex families, which had only a single ASD ...proband and neurotypical (NT) siblings, through the Simons Simplex Community at the Interactive Autism Network (SSC@IAN). Fecal samples and metadata related to functional GI disorders and diet were collected from ASD probands and NT siblings of ASD probands (age 7-14). Functional gastrointestinal disorders (FGID) were assessed using the parent-completed ROME III questionnaire for pediatric FGIDs, and problem behaviors were assessed using the Child Behavior Check List (CBCL). Targeted quantitative polymerase chain reaction (qPCR) assays were conducted on selected taxa implicated in ASD, including Sutterella spp., Bacteroidetes spp. and Prevotella spp. Illumina sequencing of the V1V2 and the V1V3 regions of the bacterial 16S rRNA genes from fecal DNA was performed to an average depth of 208,000 and 107,000 high-quality reads respectively. Twenty-five of 59 ASD children and 13 of 44 NT siblings met ROME III criteria for at least one FGID. Functional constipation was more prevalent in ASD (17 of 59) compared to NT siblings (6 of 44, P = 0.035). The mean CBCL scores in NT siblings with FGID, ASD children with FGID and ASD without FGID were comparably higher (58-62 vs. 44, P < 0.0001) when compared to NT children without FGID. There was no significant difference in macronutrient intake between ASD and NT siblings. There was no significant difference in ASD severity scores between ASD children with and without FGID. No significant difference in diversity or overall microbial composition was detected between ASD children with NT siblings. Exploratory analysis of the 16S rRNA sequencing data, however, identified several low abundance taxa binned at the genus level that were associated with ASD and/or first order ASD*FGID interactions (FDR <0.1).
This study investigates how dynamic fluctuations in matrix stiffness affect the behavior of cardiac fibroblasts (CFs) within a three-dimensional (3D) hydrogel environment. Using hybrid hydrogels with ...tunable stiffness, we created an in vitro model to mimic the varying stiffness of the cardiac microenvironment. By manipulating hydrogel stiffness, we examined CF responses, particularly the expression of α-smooth muscle actin (α-SMA), a marker of myofibroblast differentiation. Our findings reveal that increased matrix stiffness promotes the differentiation of CFs into myofibroblasts, while matrix softening reverses this process. Additionally, we identified the role of focal adhesions and integrin β1 in mediating stiffness-induced phenotypic switching. This study provides significant insights into the mechanobiology of cardiac fibrosis and suggests that modulating matrix stiffness could be a potential therapeutic strategy for treating cardiovascular diseases.
For studying the strata behavior due to multi-slicing top coal caving longwall mining along-the-strike direction in steeply dipping extra thick coal seams, the shield support pressures of the upper ...and lower slices of panel 37220 in Dongxia Coal Mine were monitored using the KJS13 dynamic monitoring system. The set up rooms adopted the ＂horizontal line-arc segment-inclined line＂ form and used different types of shield supports. The results show that the strata pressure of upper slice panel 37220-1 changed slightly along the strike direction, while along the dip direction it exhibited strong to weak pressure from bottom to top. The first weighting interval of lower slice panel 37220-2 was about 60.8 m, and the average peri- odic weighting interval were about 22.6 m. The strata behavior of panel 37220-2 exhibited a spatio- temporal characteristic in that periodic weighting occurred first in the middle-upper part, followed by the middle and upper parts, arc segment, and finally the lower part. During the periodic weighting, the weighting interval and intensity also exhibited strong space characteristics. The average dynamic load coefficient was 1.48 and the maximum lateral load of the side shield was 20-25 MPa.
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