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The rapid growth of the digital economy has heightened concerns over its environmental impacts, particularly in terms of carbon dioxide emissions. In contrast to previous studies that focus on the positive effects of digital technology on reducing carbon emissions, this paper provides a detailed analysis of the various factors that influence digital economy carbon emissions and their interrelationships, using the system dynamics method to simulate and predict China's future digital economy carbon emission baseline from 2016 to 2046. Four different scenarios were established by adjusting parameters for the percentage of the digital economy, e-waste growth rate, and data center power consumption. The simulation results indicate the following: (1) The baseline scenario shows China's digital economy carbon emissions peaking at 1.9045 billion tons in 2041 after an initial increase and subsequent decrease. (2) Single-policy simulations indicate that changing the digital economy's scale and e-waste growth independently leads to peak emissions of 1.9205 billion tons and 1.5525 billion tons, respectively. Adjusting data center power consumption has a greater impact, increasing the peak emissions to 2.1675 billion tons, a 13.82% rise from the baseline. (3) Under the comprehensive regulation scenario, emissions peak in 2040 at 2.0813 billion tons, considering the interactions between the digital economy, data center power, and e-waste. Based on the findings, we recommend fostering innovation in the digital industry, enhancing the e-waste treatment process, strategically developing digital infrastructure, and exploring effective carbon reduction strategies for the digital economy aimed at supporting China in achieving its dual-carbon goals. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the submarine has large cross dip and longitudinal obliquity,a double ball shell rotary docking joint skirt is designed. According to the working principle of the docking device,the posture equation and kinematics model of the butt skirt are derived,and according to its kinematic model to obtain the accident submarine at different angles that the direction skirt and angle skirt angle of rotation required. The sealing structure and sealing principle of key revolute joint was studied,the Yeoh model was used as the super-elastic constitutive relation curve of the O-ring to fit the corresponding material parameters. The finite element simulation of the sealing structure was carried out,the location of the dangerous section is obtained,and the reasonableness of the seal structure is verified by the analysis of the contact stress of the dangerous section. The docking skirt can be used to complete the docking task of the accident submarine with large inclination,strong current and low visibility. Greatly improving the rescue success rate,reducing the difficulty of rescue.

The rotating butt skirt is works in the deep water area of the ocean,In order to solve the safety problem of rotating butt skirt working in deep water,In this paper,fixed skirt,direction skirt,angle skirt was took as the research object.Multi-Objective Genetic Algorithm is used to optimize the key parameters of fixed skirt,direction skirt and angle skirt,and we get the optimal parameters of the three. The results show that the optimized fixed skirt reduces weight by 9. 76% after optimize,optimized direction skirt and angle skirt reduces weight by 13. 56% after optimize. And the fixed skirt,the direction skirt and angle skirt after optimized are meet the design requirements. Finally,the three-dimensional model of the rotating butt skirt was established by using the optimized data,and the test prototype was made,which laid the foundation for the subsequent sea test.

ZSM-5 zeolite is a kind of high-value-added porous aluminosilicate zeolite. The use of the coal gasification slag utilization process by-product desilication liquid as a silicon raw material to replace the current raw materials such as water glass will help reduce production costs and achieve high-value utilization of solid waste. ZSM-5 zeolites for volatile organic compounds (VOCs) adsorption were prepared by a one-step hydrothermal method using the desilication solution prepared from coal gasification slag as the main silicon source and sodium source. The effects of crystallization reaction time, the crystallization temperature, the Na2O/SiO2 molar ratio, and the SiO2/Al2O3 molar ratio on the relative crystallinity and the specific surface area of the ZSM-5 zeolite were investigated and optimized. The optical reaction conditions were as follows: a crystallization time of 12 h, a crystallization temperature of 170 °C, a Na2O/SiO2 molar ratio of 0.2, and a SiO2/Al2O3 molar ratio of 200. The optimal ZSM-5 zeolite synthesized is hexagonal, with regular grains, a relative crystallinity of 101.48%, a specific surface area of 337.48 m2·g−1, and a pore volume of 0.190 cm3·g−1. And the optimal ZSM-5 zeolite was composed of SiO2 content of 97.52 wt%, Al2O3 content of 1.58 wt%, Na2O content of 0.33 wt%, and SiO2/Al2O3 molar ratio of 104.93. Na2O/SiO2 molar ratio is 0.0033. The results of static adsorption experiments show that the static adsorption capacities of ZSM-5 zeolite for p-xylene, benzene, toluene, and butyl acetate were 118.85, 69.98, 68.74, and 95.85 mg·g−1, respectively, which can effectively adsorb VOCs. The synthetic process of the ZSM-5 zeolite is a simple preparation process and short in synthesis time. The results of this study not only help to realize the high-value utilization of silicon components in solid waste, but also provide an economical and effective way to synthesize VOCs adsorption materials. [ABSTRACT FROM AUTHOR]

Large amounts of selective catalytic reduction (SCR) denitrification catalysts with poor mechanical property are disposed and difficult to be regenerated, resulting in environmental pollution. For spent SCR denitrification catalyst, the ratio of V 4+ /V 5+ decreased by about 45% and Fe impurity increased >10 times, which influenced the recycling of the supporter. Selective leaching of V and Fe by oxalic acid and its reaction mechanism were investigated. Under the optimized leaching condition: oxalic acid concentration of 1.0 mol/L, reaction temperature of 90 °C, liquid-to-solid ratio of 20 mL/g, <75 μm particle size and leaching time of 180 min, the leaching efficiencies of V and Fe reached over 84% and 96%, respectively. The reaction mechanism for the selective leaching of these metals was determined through UV-VIS spectrophotometry and CO 2 emission analyses. After dissolution and complexation, VO 2 + and Fe 3+ were reduced to water-soluble cations VO 2+ and Fe 2+ . When V and Fe was in the specific forms of VOC 2 O 4 and Fe(C 2 O 4 ) 2 2− at 0.33 pH, high leaching efficiency was obtained. It indicated that redox reactions led to the broken of dissolution and complexation equilibriums for VO 2 + , VO + and Fe 3+ . For W and Ti, only dissolution and complexation reactions occurred and the leaching efficiency was limited by the solubility. The leaching residue with anatase TiO 2 was recovered as carrier and used for synthesis of a new SCR catalyst. [ABSTRACT FROM AUTHOR]

Alumina was leached from high-alumina coal fly ash with a NH 4 HSO 4 + H 2 SO 4 mixed solution. The leaching behavior was systematically investigated, as were factors such as mixed solution composition and concentration, reaction time and temperature, and liquid-to-solid ratio. In optimal conditions, the alumina extraction ratios can reach 87.8%, 91.1%, and 87.5% for the three different sources of coal fly ash, respectively. The phases and morphology of the raw materials and residues were also analyzed through X-ray diffraction and scanning electron microscopy–energy dispersive spectroscopy. Results showed that mullite, which is the main form taken by alumina in high-alumina coal fly ash, can be effectively decomposed to release the alumina and induce a new amorphous silica phase in mixed solution. [ABSTRACT FROM AUTHOR]