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A significant number of geological profiles showed thick Quaternary and Neoproterozoic systems in the North China Plain. They also reveal basin structures from the Paleoproterozoic era. These structures extend over 100 km in length and span several kilometers in depth. In this paper, we establish a "two concave and one convex" basin tectonic model based on the latest data from urban active fault detection and basin tectonic patterns identified in North China. Using the finite difference method, we simulate and analyze the effects of their long-period ground shaking. The "vertical model" and "parallel model" display stronger amplification of long-period ground shaking than the regular model unaffected by submerged basin tectonics. The amplification varies across space and different time periods in both models. These suggest that the angle between the tectonic axis of the subduction basin and the rupture direction of the earthquake source may be a key factor in evaluating long-period ground shaking amplification in subduction basin structures. The analysis of spectral ratios indicates that subduction basin tectonics can amplify the peak ground shaking up to three times. The amplification could last for certain periods within a specific epicentral distance range. Such an amplification effect is significant for seismic hazard risk assessment and cannot be overlooked. This study provides a reference for future urban seismic hazard risk analysis in North China.

CeO2plays an important role in heterogeneous catalysis, and its performance is highly dependent on the oxygen vacancies and surface defects, which can be easily tuned by manipulating the particle dimensions and morphology. In this article, we report a facile strategy to synthesize a new type of CeO2with modified surface property which can improve its ability to active oxygen. The obtained ball-type 3D self-assemble CeO2(M-CeO2) is composed of large amounts of small 1D crystals which are strongly connected with each other. Detailed characterizations confirm its morphology, particle size and improved reducibility with abundant fraction of Ce3+and more surface active oxygen when compared with CeO2-nanorods and CeO2-nanocubes. In the catalytic wet air oxidation (CWAO) of N,N-dimethylformamide, the total organic carbon (TOC) and total nitrogen (TN) conversion of M-CeO2at 180 °C in 3 h are 68% and 46%, respectively, which are higher than that of CeO2-nanorods and CeO2-nanocubes. Besides, M-CeO2presents the lowest activation energy, which is related to its modified surface property. The good stability with consecutive four reactions of M-CeO2in catalytic reactions suggests its potential application in CWAO processes for industrial wastewater treatment.

Foamed plastics do not readily degrade, but degradable starch foam has uneven pores and poor mechanical properties. To improve the cushioning performance of starch foams, a sustainable starch-based packaging cushioning material is prepared via microwave foaming using waste corrugated paper fibers as the reinforcement material. The effects of different fiber contents on the structure and cushioning properties of starch-based foams are studied, and the possibility of replacing petroleum-based foams is discussed through comparisons with conventional cushioning materials. The results indicate that the pore structure of starch-based foaming materials can be controlled by changing the fiber dosage, and a small or excessive amount of fiber is not conducive to the uniform foaming of starch-based composite foams. When 3 g of waste-paper fiber (17.6% by weight of the starch) is added, the average diameter of the starch-based foam pores is small, the pore size distribution is relatively uniform, the minimum buffer coefficient is 4.38, and the mechanical properties are closer to those of expanded polystyrene (EPS). A peak acceleration of 942.89 m/s2is obtained from the packaging parts with starch-based foaming materials after drop testing, which reduced the impact load by nearly 50% compared to packaging without the cushioning liner. This has the potential to become a sustainable alternative to petroleum-based packaging foams.

In diesel adsorption desulfurization, the coordination bonding between the adsorbent and sulfur compounds is interfered by aromatic compounds in diesel. Transition metal cation exchanged zeolites Y has exhibits exceptional anti-interference performance. In this work, the influence of electron configuration on coordination bonding is explored, specifically between the adsorbent and substrate, using both experimental and DFT theoretical methods. Initially, NiY, CuY and ZnY were synthesized and evaluated for their desulfurization performance in model solution (sulfur content: 25 ppmw dibenzothiophene [DBT]) with two toluene concentrations (1 w% and 3 w%). It is found that CuY showed the highest performance with retention rate at 70.2 %. Subsequently, DFT calculations revealed the binding energy between Cu(II) and DBT was −2.71 eV, higher than Ni(II) and Zn(II), and that between Cu(II) and toluene was −1.75 eV, lower than Ni(II) and Zn(II), indicating that the highest binding energy difference was responsible for the best adsorption capability. Apart from these, wave function analysis show the electron configuration between Cu(II) and DBT had the highest binding energy difference. Finally, the impact of electron configuration on adsorption performance is further investigated by modulating the electron configuration of Ni(II) to enhance/suppress its adsorption capability. According to the findings of this study, tuning the electron configuration is an effective strategy to develop materials in adsorptive desulfurization particularly for extra low sulfur content.

Surface properties of nanoceria can strongly affect the catalytic performance in oxidation reactions. In this work, a simple but efficient post-treatment, where H2O2is used as a complexing agent to dissolve Ce3+from the surface of CeO2nanorods with the help of ultrasonic treatment, is carried out to tune the surface properties and increase their catalytic performance for catalytic wet air oxidation (CWAO) of phenol. It is found that the dissolution of Ce3+from the surface of CeO2nanorods can create more surface defects and result in a much rougher surface. The H2O2–ultrasonic treatment can also increase Ce3+concentration, create more surface oxygen vacancies, and narrow the band gap of CeO2nanorods. These properties enable H2O2–ultrasonic-treated CeO2nanorods (CeO2-H2O2-sf) to possess strong oxidizing ability to effectively oxidize phenol. Additionally, for the sake of comparison, other post-treatments, including calcination, H2O2, and ultrasonic–H2O, are also imposed on CeO2nanorods.

In this paper, Ni/Zr–Yb–O catalysts with different sodium contents are prepared by a co-precipitation method, using aqueous Na2CO3solution as a precipitant, and the effect of sodium on the catalyst structure and catalytic performance for syngas methanation is extensively investigated using five Ni/Zr–Yb–O catalysts, containing 0, 0.5, 1.5, 4.5 and 13.5 wt% Na+, those are denoted as Cat-1, Cat-2, Cat-3, Cat-4 and Cat-5 respectively. It is found that the interaction between Ni and support determines the catalytic performance of Ni/Zr–Yb–O and the residual sodium content negatively affects the interaction between Ni and support. Cat-1 exhibits an excellent catalytic performance. During a long run time of 380 h, no deactivation is observed and both CO conversion and CH4selectivity maintain a level above 90%. However, Cat-3 and Cat-5 suffer rapid deactivation under the same reaction condition. The characterization results indicate the strong interaction between Ni and support enables Cat-1 to possess well dispersed Ni species, resistance to sintering and carbon deposition and thus the excellent catalytic performance. However, the presence of sodium ions over Ni/Zr–Yb–O degrades the interaction between Ni and support and the catalytic performance, especially for the stability. The relative weak interaction between Ni and support results in severe sintering of both ZrO2and Ni under the reaction condition, carbon deposition and the poor catalytic performance.

The catalytic performance of CoAPO-11 can be significantly improved viasacrificing the ligand. By doping a small amount of Co and imidazole on APO-11, we obtained highly crystalline materials with different degrees of Co embedding. This feature was verified by XRD, UV-vis spectroscopy, H2-TPR and ESR. The appropriate degree of embedding results in a large amount of Lewis acid active sites in CoAPO-11 which becomes a highly active catalyst for n-butene skeletal isomerization.

δ-MnO2with a very high amount of Mn4+showed high catalytic activity and stability for the catalytic wet air oxidation (CWAO) of phenol at a very low temperature of 70 °C. The abundance of Mn4+and reactive surface oxygen species in this catalyst, its resistance to Mn leaching, and its repeatable Mn4+/Mn3+(Mn4+/Mn2+) redox cycles contributed greatly to its remarkable catalytic performance.

ZSM-22 zeolites were synthesized using different structure-directing agents (SDAs) with varying alkyl chain lengths, including n-alkyldiamines (DAB, DAH, DAO, and DAD) and lauryl amine (LA). The characteristics of the resulting samples (denoted as “Z-SDA”) revealed that optimal elongation of SDA alkyl chains brought about a decrease in crystallization time while retaining ZSM-22 crystal phase stability. The morphology and acidity of the samples varied as the alkyl chain length of the SDAs increased. The average crystal length ranged from 13 μm to 250 nm, and the total acid content showed a downward trend, while each sample possessed nonlinear acid site distributions. Additionally, ZSM-22-supported Pt catalysts were obtained and probed using the n-hexadecane hydroisomerization process. It was found that the activity and i-hexadecane selectivity gradually increased with the alkyl chain length of the SDAs (C4–C10). Notably, Pt/Z-DAD achieved >70% yield under specific reaction conditions, which could be attributed to the abundant mesopore network and high proportion of weak Brønsted acid site distributions.

The findings in this study provide new insight into the NiMoS model, revealing that there is a sulfur dynamic equilibrium between the NiMoS edge and the gas phase. Since the evolution of non-stoichiometric sulfur proceeds rapidly at the initial stage of hydrodesulfurization reaction, the sulfur dynamic equilibrium does not draw so much attention. The results indicate that excess sulfur on the Ni–Mo–S edge can be reduced by hydrogen to form SH groups and release H2S, which lead to a low sulfur-covered NiMoS edge and a significant increase in coordinatively unsaturated sites (CUS), resulting in an outstanding HDS activity. Apart from elucidating the effect of non-stoichiometric sulfur on the NiMoS structure, the relationship among H2S partial pressure, Sxand HDS activity has been quantitatively studied. It is expected that these results will be used to deepen the understanding of HDS reaction over promoted MoS2catalysts, as well as to guide the research on ultra-deep HDS of fuel oils.

A kinetic model has been developed for the sulfidation of NiMo/Al2O3hydrodesulfurization (HDS) catalyst, which quantitatively establishes a relationship between the HDS activity and sulfidation conditions. The model parameters were estimated by fitting a series of experimental thiophene HDS conversion data over the catalysts sulfurized under different operations. The results show that the developed model satisfactorily predicts the HDS conversion with a total average relative deviation of less than 4 %. Moreover, parametric studies were made to validate the accuracy of the model. The comparison results show that the proposed model is fairly effective in simulating the sulfidation process. It is expected that the model will be used to guide the sulfidation research of supported Mo-based catalysts and to optimize laboratory/pilot-plant sulfiding procedures.

Coal to liquid fuel has the potential to substitute the petroleum fuels due to the huge reserves of coal in the earth, the development of direct coal liquefaction technology and the application of carbon dioxide capture and storage technology. The effect of coal to liquid fuel on the combustion and emission has been investigated experimentally in a heavy-duty diesel engine. The experimental results showed that compared to diesel, the coal to liquid fuel had obviously longer ignition delay but slightly later CA50, and the higher premixed combustion ratio and maximum rate of heat release; it had the benefit in soot reduction but slightly higher HC, CO and NOxemissions. The brake specific fuel consumption of coal to liquid fuel was slightly higher than that of diesel, while the brake fuel conversion efficiency of coal to liquid fuel was slightly lower than that of diesel.Furthermore, the trade-off of NOx–soot emissions in diesel engines has been improved by coal to liquid fuel, due to the predominant evaporation rate, virtually free from sulfur and aromatics, and the longer ignition delay.