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Efficient hydrogen evolution reaction (HER) electrocatalysts are crucial for renewable energy storage and conversion. Pt remains the most efficient HER catalyst, but its widespread application is hindered by cost and resource constraints. In this study, we investigate the HER electrocatalytic activities of free-metal SiC monolayers through doping and strain engineering. Through density functional theory (DFT) calculations, we explore the effects of B, N, S, and P doping on the HER performance of SiC. Our results reveal that B and P doping enhance the catalytic activity, with P doping showing the most promising activity due to its smaller ΔGH* values. Furthermore, we apply tensile strain to modulate the HER activity of P-doped SiC, achieving further improvements. We also construct composite structures of P-doped SiC with graphene, enhancing conductivity and catalytic performance. Our findings provide valuable insights into tailoring the HER catalytic properties of SiC monolayers, offering a pathway towards sustainable hydrogen production. [ABSTRACT FROM AUTHOR]

On-orbit absolute radiometric calibration is not only a prerequisite for the quantitative application of optical remote sensing satellite data but also a key step in ensuring the accuracy and reliability of satellite observation data. Due to the diversity of imaging conditions for optical remote sensing satellite sensors, on-orbit absolute radiometric calibration usually requires a large number of imaging tasks and manual labor to calibrate each imaging condition. This seriously limits the timeliness of on-orbit absolute radiometric calibration and is also an urgent problem to be solved in the context of the explosive growth of satellite numbers. Based on this, we propose a general on-orbit absolute radiometric calibration method compatible with multiple imaging conditions. Firstly, we use a large amount of laboratory radiometric calibration data to explore the mathematical relationship between imaging conditions (row transfer time, integration level and gain), radiance, and DN, and successfully build an imaging condition compatibility model. Secondly, we combine the imaging condition compatibility model with cross calibration to achieve a general on-orbit absolute radiometric calibration method. We use cross calibration to obtain the reference radiance and corresponding DN of the target satellites, which calculates the general coefficient by using row transfer time, integration level, and gain, and use the general coefficient to calibrate all imaging conditions. Finally, we use multiple imaging tasks of the JL1GF03D11 satellites to verify the effectiveness of the proposed method. The experiments show that the average relative difference was reduced to 2.79% and the RMSE was reduced to 1.51, compared with the laboratory radiometric calibration method. In addition, we also verify the generality of the proposed method by using 10 satellites of the Jilin-1 GF03D series. The experiment shows that the goodness of fit of the general coefficient is all greater than 95%, and the average relative difference between the reference radiance and the calibrated radiance of the proposed method is 2.46%, with an RMSE of 1.67. To sum up, by using the proposed method, all imaging conditions of optical remote sensing satellite sensor can be calibrated in one imaging task, which greatly improves the timeliness and accuracy of on-orbit absolute radiometric calibration. [ABSTRACT FROM AUTHOR]

Based on the mixed ligands of 1,4‐bis(2,4,6‐tricarboxylpyrid‐5‐yl)benzene (H6BTPB) and 1,4‐bis(imidazol‐1‐yl)benzene (bib), a new cadmium(II) coordination polymer with the molecular formula of {[Cd(bib)(μ2‐H2O)(H2O)2](H4BTPB)0.5(bib)0.5}n (CdCP) was constructed under solvothermal condition, and displayed a 3D supramolecular structure expanded by the hydrogen bonds between the 1D [Cd(bib)(μ2‐H2O)(H2O)2]n ladder chain and the guests. Profiting from its superior stability and inherent luminescence, the prepared CdCP dispalyed great potential as a highly sensitive and selective luminescent sensor in trace detection of 3‐NT biomarker in both water and real bodily fluids through the luminescence quenching effects, with the Ksv and LODs being 2.408×105 M−1 and 30.3 nM in water, 2.230×105 M−1 and 44.7 nM in diluted urine, 2.249×105 M−1 and 43.9 nM in diluted serum, respectively. Subsequent mechanism studies indicated the synergistic effect of internal filtering effect, photo‐induced electron transfer, and fluorescence resonance energy transfer determining the luminescence quenching response of CdCP towards 3‐NT biomarker. [ABSTRACT FROM AUTHOR]

The reverse circulation down-the-hole air hammer drilling (RC-DTH) method is renowned for its efficiency in hard rock formations and exceptional dust control performance. It presents opportunities for cost-saving, efficiency improvement, energy conservation, and environmental protection. Reverse circulation drill bits are critical components of this method. This study focused on the air reverse circulation regime, investigating various geometric parameters of the RC drill bits through computational and experimental methods to enhance its dust control performance. Results indicate that increasing the layers of suction nozzles, enlarging the diameters of the suction and mixing nozzles, and optimizing the input airflow rate can effectively channel airflow toward the central passage of the drill tool. Consequently, this optimization significantly improves the dust control performance of the RC drill bits. Conversely, increases in the flushing nozzle diameter and alterations in the suction nozzle location have detrimental effects on the dust control capability of the RC drill bits. Field tests were conducted at the Yuan Jiacun iron mine, affiliated with Taiyuan Iron and Steel (Group) CO., LTD. The field tests demonstrate that the optimized RC drill bit exhibits excellent dust performance. [ABSTRACT FROM AUTHOR]

Inspired by designing distinguished optical materials, novel organic molecules with ESIPT characteristics have become the hot topic in current research. Dual-m-N,N-dimethylaniline substituted HBO derivative (DNHBO), as a kind of new dual solid-state and solution-state emission (DSSE) emitter, is focused on its excited state dynamics theoretically in this work. Considering four aprotic solvents with different polarities, the solvent-polarity-regulated photo-induced hydrogen bonding interactions and associated ESIPT behaviours are confirmed. Briefly speaking, via comparing and metering the magnitudes of excited-state reaction barriers in different solvents, we claim that nonpolar solvents drive the ESIPT reaction for DNHBO fluorophore. [ABSTRACT FROM AUTHOR]