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The United Nations included reducing harvest losses as a Sustainable Development Goal in 2015, sparking heightened research and policymaker interest in reducing losses to ensure food security. High-standard farmland construction plays a crucial role in ensuring food security. Few studies have combined high-standard farmland construction with grain harvest losses. Drawing on the data from the 2022 Chinese Post-Harvest Loss Survey (CPHLS 2022), the study utilizes OLS (ordinary least square) and quantile regression models to explore the impact of high-standard farmland construction on grain harvest losses. Empirical results show that high-standard farmland construction can significantly reduce grain harvest losses. The research conclusions are still valid after passing a series of robustness tests. The heterogeneity analysis shows that high-standard farmland construction significantly impacts on grain harvest losses for farmers in major grain-producing areas, plain areas, and eastern regions. Mechanism analysis reveals that high-standard farmland construction mainly reduces grain harvest losses by expanding operational scale and enhancing mechanization application. Based on research findings, the Chinese government should formulate a targeted high-standard farmland construction policy, optimize the agricultural machinery operating environment, and promote appropriate operational scale to ensure national food security. [ABSTRACT FROM AUTHOR]

A novel approach to "treating waste with waste" was proposed to prepare porous ceramsite for the treatment of sewage containing Ag+ with total phosphorus tailings as raw material. The porous ceramsite with bulk density of 1.11 g/cm3 was fabricated via rotary granulation technique, followed by sintering at 1085 °C, whose compressive strength, water absorption, and hydrochloric acid solubility were 1.23MPa, 43.8%, and 15%, respectively. Effects of NaCl concentration, solid-liquid ratio, modification temperature, and modification time were studied in this study. After the porous ceramsite was modified by 1 mol/L NaCl solution at 70 °C for 4 h, the removal rate of Ag+ for modified ceramsite reached 99.9%. The high Ag+ removal rate was related to the surface microstructure of porous ceramsite. Numerous micro pores appeared on the surface of ceramsite after NaCl modification, which provided more contact sites for the adsorption of Ag+ by the adhered Cl− on ceramsite surface. The high removal rate of modified ceramsite for Ag+ makes it a highly promising for application in sewage disposal. [ABSTRACT FROM AUTHOR]

In order to research the forming mechanism of zonal disintegration, the stress distribution of surrounding rock in deep roadway was studied through three dimensional photoelastic test with stress freezing. In this work, the loads of 5, 30, 50, 70 and 90 kN were respectively applied to the axes of the roadway based on radial constraint in photoelastic test models, also the stress fields of surrounding rock were transparently presented via observing photoelastic slice. The results show that when the axial stress reaches a certain level, the stress distribution of surrounding rock of roadway is presented as concentric circles of roadway, and the stress shows its maximum near roadway. In addition, the number of stress circles increases and the level of stress improves with increasing axial stress of roadway, and the increased distance between the area of maximum stress and roadway surface can be obtained. Studies show that the range of layered fractures is determined by the magnitude of the axial stress, which is a critical influence on zonal disintegration. Furthermore, high stress 'bypass' roadway as the axial loads increases. The method of three dimensional photoelastic test brings methodological progress for the study of zonal disintegration. The research results can provide new ideas for the stability control of surrounding rock, and give a theoretical guidance for the roadway excavation and supporting design. [ABSTRACT FROM AUTHOR]