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[Display omitted] • • The novel reactor allows dry anaerobic digestion of food waste (FW) and straw. • • The methane yield of FW and straw co-digestion could reach 494.2 mL CH 4 /g VS. • • FW significantly improved the anaerobic biodegradability of the substrate (85.7%). • • Co-digestion can improve hydrolysis and acid production efficiency. • • The acetotrophic methanogenic pathway significantly affects the methane yield. Gradient anaerobic digestion reactor (GADR) can improve substrate utilization efficiency by solving the problem of the "short circuit" of materials. However, the substrate's composition significantly affects the reactor's performance. This study investigated the impact of food waste (FW) levels on corn straw's dry anaerobic digestion (AD) in a novel GADR. The results show that biomethane production can be improved by coupling urban and agricultural solid waste recycling. The mechanism is to increase the hydrolysis and acid production efficiency, and the abundance of enzymes related to methanogenesis. The maximum methane yield (494.2 mL CH 4 /g VS) and the highest anaerobic biodegradability (85.7 %) were obtained when the FW was added at 60 %. The co-digestion of FW and straw can improve the hydrolysis and acid production efficiency and methane yield, which improves the buffering capacity and stability of the system compared with the single digestion of FW. [ABSTRACT FROM AUTHOR]

Grain boundary diffusion (GBD) is an effective process to enhance the thermal stability and coercivity of sintered Nd-Fe-B magnets, but the low diffusion efficiency and high consumption of heavy rare earth (HRE) elements prevent further performance improvement and cost reduction of the magnets. Here, a Ni-containing dual-alloy Pr-Ni-Al/Dy-Ni-Al diffusion source is used to enhance both the diffusion efficiency of the Dy element and the anti-corrosion properties of Nd-Fe-B magnets. Pr-Ni-Al and Dy-Ni-Al alloys with different melting points exhibit different diffusion behaviors. The diffused low-melting Pr-Ni-Al alloy can construct continuous grain boundary, acting as an effective diffusion channel for the GBD of Dy-Ni-Al. As a result, the coercivity was enhanced from 1057 to 1662 kA/m by dual-alloy diffusion. For comparison, the coercivity increased only to 1548 kA/m by the diffusion of Pr-Dy-Ni-Al single-alloy with the same element contents. It was confirmed by composition and microstructure characterizations that Pr-Ni-Al/Dy-Ni-Al diffusion leads to a deeper diffusion of Dy. The constitution of continuous grain boundary phase and core-shell structure attributed to the enhancement of coercivity. Different from many HRE-based diffusion sources, the present Ni-containing sources can also greatly enhance the anti-corrosion properties of Nd-Fe-B magnets after GBD. The dual-alloy diffusion with low consumption and high diffusion efficiency of HREs, thus, shows good prospect for practical applications. • A Pr-Ni-Al/Dy-Ni-Al dual-alloy is proposed as grain boundary diffusion source. • Low-melting Pr-Ni-Al alloy provides diffusion channels for deep diffusion of Dy. • Deep diffusion and core-shell structure lead to enhanced coercivity. • Increased electric potential of GB phase results in improved corrosion resistance. [ABSTRACT FROM AUTHOR]

• Compared to TI120, MI120 and MI150 significantly increased grain yield and WUE. • MI90 ensured grain yield by significantly improving thousand grain weight. • Except for MI60, MI treatments significantly delayed the senescence of flag leaf during grain filling. • MI treatments ensured the water supply in the mainly root distribution zone of wheat. • MI with reducing irrigation promoted water consumption of the deep soil profile. It's very important to guarantee the wheat production and improve water productivity in the North China Plain (NCP). In order to reduce irrigation and ensure the crop production in the NCP, a two-year field experiment of winter wheat was conducted in 2016–2018 using micro-sprinkling irrigation including different irrigation amount treatments (60 mm, MI60; 90 mm, MI90; 120 mm, MI120; and 150 mm, MI150), and the local traditional water-saving and productive flooding irrigation method (TI120) was as a control. The grain yield (GY), dry matter accumulation (DM), root system distribution and water utilization were investigated. The results showed that, the GY of MI60 decreased by 5.1–13.4% compared with TI120; GY of MI90 was comparable with TI120, while that of MI120 and MI150 increased significantly. The higher GY in micro-sprinkling treatments was mainly due to the significant increase of 1,000-grain weight (TGW), which was the result of the significant delay of the senescence in flag leaves during grain filling and then the increase in the post-anthesis DM. In addition, the roots mainly distributed in the 0−60 cm soil profile, and micro-sprinkling ensured the soil water supply in this areas at the critical growth stages; what's more, micro-sprinkling with reducing irrigation treatments significantly promoted the growth of root system to the deep soil layer, which improved the absorption and utilization of moisture stored in soil. Compared with TI120, the same irrigation amount treatment under micro-sprinkling (MI120) significantly increased water use efficiency (WUE) due to higher GY and lower seasonal evapotranspiration (ET); the 125% irrigation amount treatment (MI150) increased WUE due to higher GY and comparable ET; the 75% irrigation amount treatment (MI90) obtained the similar WUE to TI120; the 50% irrigation amount treatment (MI60) got similar or lower WUE to TI120. Overall, suitable reduction of irrigation amount under micro-sprinkling (MI90) can ensure the grain yield of winter wheat and efficient utilization of irrigation water in the NCP. [ABSTRACT FROM AUTHOR]