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Summary: As environmental awareness grows, the agricultural sector must balance rising product demands with sustainable development. This study investigates the relationship between agricultural trade and green technological innovation, emphasizing how trade-induced efficiency improvements promote input-saving practices. Using panel data from 31 Chinese provinces between 2011 and 2021, our analysis reveals that agricultural trade significantly enhances resource use efficiency, particularly in rural areas where agriculture is concentrated. The findings provide empirical evidence of the positive effects of trade on green innovation and highlight the need for targeted policy interventions to support sustainable agricultural practices. This research underscores agricultural trade’s critical role in fostering green innovation and offers valuable insights for policymakers and agricultural businesses seeking to improve competitiveness and sustainability in an increasingly globalized economy.

With the background of carbon neutrality, the resource and energy utilization of excess sludge (ES) have become the focus of future research. The pyrolysis of ES can produce biochar and enrich phosphorus (P). In this paper, the existing forms and recovery efficiencies of P in biochar from ES (BCES) were investigated. The results showed that the total phosphorus (TP) content of BCES at 850 °C was 65.1 mg/g, and the inorganic phosphorus (IP) content was 64.2 mg/g. The TP content of BCES was two times heavier than that of ES. The main ingredient of ES was quartz (SiO2), while the main phases of BCES were quartz (SiO2) and aluminum phosphate (AlPO4) at 650 –850 °C, and P mainly existed in the form of AlPO4. When the pyrolysis temperature was 800 and 850 °C, two new minerals appeared: Ca5(PO4)3OH and CaZn2(PO4)2·2H2O. Based on the conditions of a leaching time of 150 min, a H2SO4 concentration of 0.2 mol/L, a stirring rate of 220 rpm and a liquid–solid ratio of 50 mL/g, the leaching efficiency of P in BCES was found to be 100%. The pyrolysis temperature had no effect on leaching efficiencies of P; however, a higher pyrolysis temperature promoted metal leaching content. ;

The superhydrophobic silica glass microchannel with flow drag reduction performance has broad application prospects. In response to this demand, this paper proposes an integrated design and preparation method of structure and function for drag reduction microchannels on the silica glass surface. The design method of geometric parameters of stable superhydrophobic silica glass surface structures with a periodic micropillar array is studied based on the drag reduction mechanism of superhydrophobic surfaces. Combined with the plasma deposition process, the drag-reducing superhydrophobic silica glass surface is successfully prepared by femtosecond laser technology. The prepared drag-reducing superhydrophobic silica glass surface shows good composite wetting state stability under different test conditions. The drag-reducing superhydrophobic functional structure with a micropillar array is prepared at the bottom of the silica glass microchannels by femtosecond laser direct writing technology. Moreover, the effective integration of the silica glass microchannel structure and the drag-reducing functional structure is achieved. The preparation and flow performance test of microfluidic devices demonstrates that drag-reduction microchannels of silica glass can significantly reduce microfluidic flow resistance. The proposed method effectively improves the functional characteristics of ultrafast laser processing surface microchannels in silica glass and has broad application prospects in fluid flow and control.

In this work, the effects of electroplated Cu (EP Cu) and Cu addition (0.7%) in Sn solder on the intermetallic compounds (IMCs) growth and void formation were clarified by comparison with solder joints comprising of high purity Cu (HP Cu) substrate and pure Sn solder. After aging processes, a new IMC, Cu3Sn, was formed at the interface, in addition to Cu6Sn5 formed in the as-soldered joints. The EP Cu and Cu addition (0.7%) both had limited effects on the total IMCs thickness. However, the effects varied on the growth behaviors of different IMCs. Comparing to the void-free interface between Sn and HP Cu, a large number of voids were observed at the Cu3Sn/Cu interface in Sn/EP Cu joints. The formation of these voids may be induced by the impurities and fine grain, which were introduced during the electroplating process. The addition of Cu suppressed the inter-diffusion of Cu and Sn at the interface. Consequently, the growth of the Cu3Sn layer and formation of voids were suppressed.

Joining Al alloy to steel is of great interest for application in the automotive industry. Although a vast number of studies have been conducted to join Al to steel, the joining of Al to steel is still challenging due to the formation of brittle Fe–Al intermetallic compounds. In this work, the microstructure and mechanical properties of the dissimilar Al/steel joints with and without a nickel coating are comparatively investigated. A homogenous reaction layer composed of FeZn10 and Fe2Al5 is formed at the interface in the joints without Ni coating, and the joint facture load is only 743 N. To prevent the formation of brittle Fe2Al5, Ni electroplated coating is applied onto a steel surface. It has been shown that a nonhomogeneous reaction layer is observed at the interfacial region: Ni5Zn21 is formed at the direct irradiation zone, while Al3Ni is formed at the fusion zone root. The microhardness of the interfacial layer is reduced, which leads to the improvement of the joint mechanical properties. The average fracture load of the Al/Ni-coated steel joints reaches 930 N. In all of the cases, failure occurs at the Ni coating/fusion zone interface.