Foghdideriksen0698

Iron tailings are fine, stable and complex materials, which are mainly composed of minerals and metal oxides. Residual silicon in iron tailings can be used to prepare mesoporous silica materials applied to energy storage, environmental protection and other fields. This paper reported a novel synthesis strategy from iron tailings to high-surface area hexagonally ordered mesoporous silica materials in an innovative non-hydrothermal system at room temperature. A pretreatment process involving acid leaching and hydrothermal alkaline reaction was vital to the successful utilization of iron tailings. X-ray fluorescence (XRF) data suggested that about 95% of the silicon of iron tailings changed to the silicate as a silicon source. The samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), N2-adsorption-desorption isotherms, Fourier transform infrared (FTIR) spectroscopy, Thermogravimetry and differential scanning calorimetry (TG-DSC) and 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy. The SAXRD patterns of mesoporous silica materials exhibited an intense (100) diffraction peak and two weak (110, 200) diffraction peaks, corresponding to characteristic of the ordered mesoporous lattice. TEM images further confirmed the hexagonally ordered porous structure of mesoporous silica materials. The WAXRD patterns and 29Si MAS NMR spectra of the samples indicated that mesoporous silica materials were composed of amorphous SiO2. The obtained mesoporous silica materials had a high surface area of 1915 m2/g and pore volume of 1.32 cm3/g. Furthermore, the evolution from iron tailings to mesoporous silica materials was elucidated and a proposed synthesis mechanism was discussed. Collectively, these results provided an insight into efficient recycling of iron tailings and the production of advanced functional materials from solid waste.Microplastics (MPs) are widely distributed in aquatic environments. They may release toxic substances or act as carriers for other organic compounds and pathogens, with potential to cause harm to the ecological environment and human health. A key concern is how MPs interact with organic compounds. We reviewed related works conducted under both laboratory conditions and in field aquatic environments to investigate the mechanisms of interactions between MPs and organic compounds from three perspectives MPs, organic compounds, and environmental factors. The crystallinity and specific surface area of the MPs, and the functional groups, ionic form and strength of both MPs and organic compounds are key factors affecting their interactions. Environmentally realistic concentration settings for both MPs and organic compounds are critical for interpretation of the results of sorption experiments. The effect of salinity on interactions is mainly due to changes in pH. These results contribute to a better understanding of the environmental behavior, and potential ecological and human health risks of microplastics.The analysis of energy carrying capacity (ECC) is an important basis for measuring the sustainable development level of regional energy carrying systems (ECS) and the selection of regional development models. This study establishes a regional ECS structure model from four subsystems energy resources, economic development, social development, and ecological environment. The synergistic development relationship between subsystems and the feedback relationship between key elements are analyzed. Using a system dynamics model, the catastrophe progression method and the coupling coordination model are applied to rate the ECC and the coupling coordination degree (CCD) of China's ECS from 2004 to 2018. Furthermore, the status continuation scenario (SCS), policy planning scenario (PPS), strengthen policy scenario (SPS), and policy comparison scenario (PCS) are set up to carry out the multi-scenario simulation of China's ECC, and ECC and CCD in four scenarios from 2019 to 2050 are analyzed. The results reveal that from 2004 to 2018, the socioeconomic, the energy resources, and the energy environment carrying capacities to varying degrees, and the level of China's ECC and CCD increased year by year. It entered a comparably weak carrying level in 2010 and optimized from the uncoordinated stage to the primary coordinated stage in 2008. From 2019 to 2050, the ECC will reach the platform period in 2036 under PPS, and under SPS and PCS it will reach the platform period in 2030; the ECC stages and development coordination optimization nodes are both manifested as that SPS is the earliest, PCS is second, and PPS is the latest. this website In the future development process, it is recommended that take PPS as the bottom line and SPS as the goal, with high carrying capacity and superior coordinated stages as the guide, and the sustainable development capacity supported by ECS should be strengthened.Leaching losses of dissolved organic carbon (DOC) and nitrogen (DON) from agricultural systems are important to water quality and carbon and nutrient balances but are rarely reported; the few available studies suggest linkages to litter production (DOC) and nitrogen fertilization (DON). In this study we examine the leaching of DOC, DON, NO3-, and NH4+ from no-till corn (maize) and perennial bioenergy crops (switchgrass, miscanthus, native grasses, restored prairie, and poplar) grown between 2009 and 2016 in a replicated field experiment in the upper Midwest U.S. Leaching was estimated from concentrations in soil water and modeled drainage (percolation) rates. DOC leaching rates (kg ha-1 yr-1) and volume-weighted mean concentrations (mg L-1) among cropping systems averaged 15.4 and 4.6, respectively; N fertilization had no effect and poplar lost the most DOC (21.8 and 6.9, respectively). DON leaching rates (kg ha-1 yr-1) and volume-weighted mean concentrations (mg L-1) under corn (the most heavily N-fertilized crop) averaged 4.5 and 1.0, respectively, which was higher than perennial grasses (mean 1.5 and 0.5, respectively) and poplar (1.6 and 0.5, respectively). NO3- comprised the majority of total N leaching in all systems (59-92%). Average NO3- leaching (kg N ha-1 yr-1) under corn (35.3) was higher than perennial grasses (5.9) and poplar (7.2). NH4+ concentrations in soil water from all cropping systems were relatively low ( less then 0.07 mg N L-1). Perennial crops leached more NO3- in the first few years after planting, and markedly less after. Among the fertilized crops, the leached N represented 14-38% of the added N over the study period; poplar lost the greatest proportion (38%) and corn was intermediate (23%). Requiring only one third or less of the N fertilization compared to corn, perennial bioenergy crops can substantially reduce N leaching and consequent movement into aquifers and surface waters.