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Damage to the back of mined ore body caused by the strong impact effect of blasting has always been a focus of scientific research workers. Based on the engineering background of parallel deep blasthole blasting in the Gongchangling underground mine of Anshan Iron and Steel Group, the blasting characteristics induced by blasting with different charge structures of the same charge are studied through theoretical analysis, numerical analysis, and field test. Firstly, the Riedel-Hiermaier-Thoma (RHT) model suitable for Gongchangling iron-rich ore was theoretically determined and verified by the Hopkinson test. Numerical simulations were performed for parallel deep blastholes with different charge structures of the same charge and the best charge structure suitable for parallel deep blasthole blasting in Gongchangling underground iron mine was obtained. The numerical results show that the RHT model can well reproduce the tensile failure behavior and three-dimensional fracture distribution of iron-rich ore samples. Through the combination of reasonable charge structure and delay time, the optimization scheme is applied to the upward parallel medium-deep blasthole blasting, which improves the blasting effect of parallel deep blasthole blasting and achieves a remarkable effect in the control of the damage to the remaining ore body caused by blasting.

Reasonable delay time between blastholes is imperative in improving the blasting effect and mining efficiency. At present, the research findings on the effect of inter-blasthole delay time in sublevel caving are sparse. In this study, the effects of different delay times between blastholes in sublevel caving were studied through numerical simulation and field tests. The results show that the fractal dimensions of the crushing zones and fractures between the blasthole decrease with the increasing delay time between blastholes; the longer the delay time, the more suppressed the blasting effect. The peak stress of short time delay between blastholes is larger than that for long time delay between blastholes in the range of the blasted room, which is conducive to rock fragmentation. Further, the peak stress field between unexploded blastholes with a short time delay is smaller than that for a long time delay, which helps protect brow lines. Thus, the short delay between blastholes can effectively protect the rear eyebrow line in field applications and improve mining efficiency.

We investigate tin oxide growth on fullerene (C60) by atomic layer deposition (ALD) for C60/oxide bilayer electron selective contacts in P-I-N metal halide perovskite (MHP) solar cells. An in situozone functionalization step is incorporated in an ALD SnOxprocess to suppress sub-surface growth, leading to improved internal barrier performance of ALD SnOxthin films grown on fullerene surfaces. We show that this approach decreases the water-vapor transmission rate of C60/ALD SnOxbarriers by an order of magnitude and improves the barrier properties against gas, solvent, and halide migration. Furthermore, ozone-treated SnOxbarriers can narrow photovoltaic performance distribution without compromising efficiency. We demonstrate the universality of this approach in wide-, intermediate-, and low-gap perovskite systems and further show that enhancement of the ALD barrier layer is critical toward improving the yield of all-perovskite tandem solar cells. Two-terminal all-perovskite tandem solar cells incorporating ozone nucleation are reported at over 24% photovoltaic conversion efficiency.

Meteorus pulchricornisis a preponderant parasitic wasp of various lepidopteran pests. The extensive application of broad-spectrum insecticides usually causes serious threats to the olfactory recognition of nontarget insects such as parasitoid wasps. However, the binding mechanism of odorant-binding proteins (OBPs) to insecticides in parasitoid wasps remains unknown. Herein, we find that the MpulOBP6 protein had a strong binding affinity to three insecticides (phoxim, chlorpyrifos, and chlorfenapyr). Results of computational simulations revealed that the hydrophobic interaction contributed by a mass of nonpolar amino acid residues was the primary driving force in the formation and stabilization of MpulOBP6–insecticide complexes. Among them, four residues (Met75, Val84, Phe121, and Pro122) and two residues (Val84 and Phe111) play an essential role in the binding of MpulOBP6 to phoxim and chlorfenapyr, respectively. Our findings could be instrumental to elucidate the effects of insecticide application toward the olfactory recognition of nontarget insects in the processes of agricultural production.

Multispectral object detection for autonomous driving is multi-object localization and classification task on visible and thermal modalities. In this scenario, modality differences lead to the lack of object information in a single modality and the misalignment of cross-modality information. To alleviate these problems, most existing methods extract information based on a single scale (e.g., these methods mainly focus on detecting significant cars or pedestrians), which leads to insufficient performance in capturing multi-scale discriminative information (e.g., small bicycles and blurred pedestrians) and safety hazards in the driving process. In this letter, we propose a Multi-Scale Aggregation Network (MSANet) consisting of two parts Multi-Scale Aggregation Transformer (MSAT) and the Cross-modal Merging Fusion Mechanism (CMFM), which combined with the advantages of Transformer and CNN to extract rich image information from two modalities by mining both local and global context dependencies. Firstly, to reduce the lack of information in a single modality, we design a novel MSAT module to extract rich details and texture from multi-scale. Secondly, to alleviate feature misalignment caused by modality differences, the CMFM is utilized to aggregate complementary information on multiple levels. Comprehensive experiments on two benchmarks demonstrate that our approach shows better results than several state-of-the-art methods.

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To acquire a further utilization of mulberry seed, antioxidant peptides derived from defatted mulberry seed protein was prepared using a continue-flow microreactor with the synergistic effects of immobilized protease and nontoxic ionic liquid. The mulberry seed meal was pretreated with the combined simultaneous ultrasound treatment at a frequency combination of 20/28/40 kHz, solid–liquid ratio of 1:30, output power of 400 W, and temperature of 40 °C; the extraction rate of mulberry seed protein was up to 70.1%, 21.54% higher than that obtained with the single-frequency ultrasonic treatment (p< 0.05). The hydrolysis process of mulberry seed protein in the continue-flow microreactor was catalyzed by the immobilized protamex combined with choline chloride, the flow rate was 2.5 mL/min, the temperature was 50 °C, and the hydrolysis rate was up to 83.33%, which was 1.14 times higher than that without ionic liquid. Moreover, the immobilized protease can be used 12 times under continue-flow condition, and the enzyme activity was still more than 80% of the original enzyme. Four antioxidant peptides including AMDGK (896.24 Da), KFRAKDG (1109.47 Da), FPSNEPLLG (1287.15 Da), and SNVPNKEL (1005.14 Da) were obtained by ionic liquid-enhanced microfluidic hydrolysis with immobilized protease from mulberry seed protein, and AMDGK had not been reported before. These peptides exhibited strong scavenging activities on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙) (EC50were 2.64, 1.89, 2.16, and 1.34 mg/mL, respectively) and superoxide anion radicals (·O2−) (EC50were 3.36, 2.78, 2.56, and 1.77 mg/mL, respectively). Thus, the defatted mulberry seed protein possesses good edible development potential and economic value in the production of antioxidant peptides.

Silkworm pupae are a typical byproduct with high protein content from silk-reeling industry. The aim of this study was to evaluate the performance of defatted silkworm pupae hydrolysate as an alternative nitrogen source to produce polysaccharides and flavonoids using the fungus Phellinus baumii. The results indicated that the defatted silkworm pupa was treated with dispase, and the freeze-dried hydrolysate had a yield of 37% and a nitrogen content of 3.18%. In the fermentation process, the content of the hydrolysates was 32 g/L. Moreover, the consuming reducing sugar accounted for 75.61% of the total reducing sugar and the nitrogen consumption accounted for 35.19% of the total nitrogen content. The maximum biomass produced by the hydrolysate treatment group was 0.6 g/L, and the extracellular flavonoid concentration was 0.4 g/L; the produced extracellular polysaccharide concentration was 7.71 g/L, which was 1.4–5.9 times higher than that of other nitrogen source treatment groups. Therefore, the defatted silkworm pupae hydrolysate is an effective alternative nitrogen source which has great economic value. As a nitrogen source reagent, it enhanced the fermentation ability of P. baumiiand increased the yield of extracellular polysaccharides and flavonoids.

A β-1,3–1,4-glucanase-encoding gene, Bisglu16B, was identified in Bisporasp. MEY-1. The deduced BisGlu16B consists of an N-terminal signal peptide, a catalytic module of glycoside hydrolase family 16 (GH16), and a C-terminal serine/proline-rich module. After expression in Pichia pastorisGS115, the purified recombinant BisGlu16B showed maximal activity at pH 4.0 and 55 °C and had broad substrate specificity (β-1,3-/β-1,4-mixed, β-1,3-, β-1,4-, and β-1,6-linked glucan, and β-1,4-mannan). The enzyme possessed high specific activities toward barley β-glucan (34 700 U·mg–1), lichenan (23 900 U·mg–1), and laminarin (9 000 U·mg–1). After removing the C-terminal module, the truncated mutant, BisGlu16B-ΔC, retained similar enzymatic properties to the wild type but displayed significantly enhanced activities (up to 2.5-fold). Functional and structural analyses indicated that the C-terminal module plays a key role in the substrate binding of BisGlu16B. This study provided an excellent candidate glucanase for industrial purposes and revealed the functions of a C-terminal serine/proline-rich region.

Additive tartaric acid (TA) in perovskite precursor solution promotes crystal growth with enhanced multiple preferential orientations leading to improved photovoltaic performance and stability.