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Multi‐metallic catalysts rely on the synergistic effect between metals to perform better catalytic effect in biomass hydrogenation experiments compared with mono‐metallic catalysts. A series of CuNiAl composite metal oxide catalysts promoted by silicotungstic acid (HSiW), which were prepared by co‐precipitation and impregnation methods, were characterized by powder X‐ray diffraction (XRD), N2‐physisorption, scanning electron microscope (SEM) and NH3 program temperature desorption (NH3‐TPD) and pyridine infrared adsorption (Py‐FTIR). Their catalytic performance was evaluated in the hydrogenation of levulinic acid (LA) to prepare γ‐valerolactone (GVL). The results showed that the addition of Cu could improve the hydrogenation activity of Ni, and the addition of HSiW could further increase the amount of acid sites in the catalysts. Both of them could enhance the conversion of LA to some extent. CuNiAl‐5SiW, the par excellence catalyst, relied on the synergistic interactions between metals as well as the Brønsted and Lewis acid active sites to show efficient hydrogenation performance. The CuNiAl‐5SiW catalyst demonstrated 96.9 % conversion of LA and more than 99 % selectivity to GVL under 2 hours of reaction time, 180 °C of reaction temperature, 3.0 MPa of initial hydrogen pressure and solvent‐free conditions. [ABSTRACT FROM AUTHOR]

Selective capture of carbon dioxide as a C1 feedstock for the preparation of high‐value chemicals has been recognised as an important way to mitigate the crisis. In this work, a new heterogeneous catalyst, Cu@CP‐PII, was developed through the rational construction of an open‐pore organic skeleton, which is easy to synthesise and highly efficient. With the synergistic effect between the high CO2 affinity of the porous skeleton and the highly dispersed Cu(I) sites of the activated alkynes, it can be used for the efficient preparation of α‐methylene cyclic carbonates at ambient temperature and pressure. The structure and morphology were exhaustively characterised by Solid State 13C‐NMR, FT‐IR, XPS, TEM and N2 adsorption‐desorption tests, and this catalyst possessed a high surface area of 273.7 m2 ⋅ g−1 and uniformly dispersion of CuI. To test its catalytic activity, Cu@CP‐PII in an amount of only 0.4 mol% was used as a catalyst for the carboxylative cyclization reaction of propargylic alcohols with CO2, which resulted in substrate conversions up to 100 % and yields greater than 99 %. In addition, controlled experiments and mechanistic elucidation confirmed that anhydrous and low temperatures are necessary to achieve high selective control of the target product α‐methylene cyclic carbonates. [ABSTRACT FROM AUTHOR]

Rising stress, mental health issues, and suicide rates among farmers highlight the need to understand factors influencing their job satisfaction. Farming presents distinct challenges with its unique mix of positive and negative characteristics. This study utilized dual‐factor theory to investigate how various factors, such as economic dynamics, farm financial health, stewardship views, experience with extreme weather, and climate change concerns, influence farmers' job satisfaction and dissatisfaction. Data from a 2020 survey of Iowa farmers were analyzed using ordinal logistic regression. Financial health, stewardship motivations, and perceived adequacy of conservation practices emerged as significant predictors of both job satisfaction and dissatisfaction. Farmers' extreme weather events experiences were positively associated with job satisfaction, indicating successful coping enhances contentment. Conversely, climate change concern was negatively associated with job satisfaction. As a revenue protection strategy, faith in crop insurance was negatively related to job dissatisfaction. In summary, besides the anticipated positive impact of farm financial health, the findings show that job satisfaction in farming is linked to stewardship motivations and perceived adequacy of conservation practices on the farm. The results suggest an opening for policies and programs aligning financial and conservation goals, potentially enhancing long‐term farmer well‐being and sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Rising stress, mental health issues, and suicide rates among farmers highlight the need to understand factors influencing their job satisfaction. Farming presents distinct challenges with its unique mix of positive and negative characteristics. This study utilized dual‐factor theory to investigate how various factors, such as economic dynamics, farm financial health, stewardship views, experience with extreme weather, and climate change concerns, influence farmers' job satisfaction and dissatisfaction. Data from a 2020 survey of Iowa farmers were analyzed using ordinal logistic regression. Financial health, stewardship motivations, and perceived adequacy of conservation practices emerged as significant predictors of both job satisfaction and dissatisfaction. Farmers' extreme weather events experiences were positively associated with job satisfaction, indicating successful coping enhances contentment. Conversely, climate change concern was negatively associated with job satisfaction. As a revenue protection strategy, faith in crop insurance was negatively related to job dissatisfaction. In summary, besides the anticipated positive impact of farm financial health, the findings show that job satisfaction in farming is linked to stewardship motivations and perceived adequacy of conservation practices on the farm. The results suggest an opening for policies and programs aligning financial and conservation goals, potentially enhancing long‐term farmer well‐being and sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of Linglong cementitious material on the consolidation of tailings under different conditions,a series of backfill blocks at different ratios,different densities and different curing ages are designed with ordinary Portland cement control and their uniaxial compressive strength is measured through strength test.Then the phase composition and the micro-morphology of the tailings backfill are discussed by such measuring and testing techniques as XRD and SEM.The results show that the hydration reaction of the cementitious material produces ettringite and C-S-H gel,and promotes the consolidation of the tailings backfill;the age and the ratio of cementitious material to tailings will affect the development of the content and morphology of ettringite and C-S-H gel in the hydration products,and the content of hydration products will increase with the increase of age and the ratio of cementitious material to tailings.The content of the products increases and overlaps to form a dense network structure,which is macroscopically expressed as an increase in strength;the mass concentration affects the pores in the test block,thereby affecting the strength.

Catalytic conversion of glycerol to lactic acid has been considered as one of the effective ways to solve the problem of glycerol surplus. In this paper, we reported a facile synthesis of Cu/ZnO/C by direct calcination of Cu-supported zeolitic imidazolate framework(ZIF-8), and the performance of the catalysts for converting glycerol to lactic acid were investigated. The properties of Cu/ZnO/C catalysts were characterized by XRD, BET, SEM and TG techniques. The results showed that nano-copper was distributed uniformly on the porous carbon carrier. The zinc oxide after thermal treatment provided abundant metal active sites and had synergistic effect with nano copper. In addition, the lactic acid selectivity of 84% was obtained at the glycerol conversion of 95.1% at 230 °C, 1.5 MPa and 15% copper loading for 6 h reaction. Moreover, the yield of lactic acid still remained above 80% after being recycled four times. [ABSTRACT FROM AUTHOR]