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[Objective] The resilience of urban network structures is a crucial guarantee for the recovery and stability of urban spatial organization. Current research predominantly employs individual flows and focuses on developed regions, and there is relatively little research that combines multidimensional factor flows while also focusing on the resilience of network structures in underdeveloped regions. Therefore, this study took the underdeveloped Northwest China as the research object and explored its network structural resilience based on multidimensional factor flow, in order to fill the gap of related research and enrich the empirical analysis of network resilience from the perspective of multidimensional factor flow. [Methods] This study focused on 51 prefecture-level administrative units in Northwest China for the year 2022. It investigated the structural characteristics of urban networks from three perspectives: economic, transportation, and information, quantitatively measured their hierarchy, matching, transmission, and agglomeration, and examined the structural resilience of Northwest China’s urban networks under various disruption scenarios by using the method of computer simulation and proposed optimization strategies from different perspectives. [Results] (1) The economic, transportation, and information networks across the 51 prefecture-level administrative units in Northwest China are generally distributed in a pattern of dense in the east and sparse in the west, showing core-periphery characteristics, but there are significant differences in the structure of the three types of networks. The economic network density is low and the stickiness between the core nodes is large, showing the characteristics of coexistence of “strong assisting weak” and “strong alliances”, with multi-group pattern and fragmented development trend. The traffic network is more closely linked, with stronger inertia in intercity links, showing a “small world” effect, a spindle-shaped pattern, and a turbulent development trend. The information network has wide coverage and strong permeability, showing coordinated characteristics, a strip-like pattern, and a turbulent development trend. (2) The three types of networks differ greatly in terms of hierarchy and matching, and less in terms of transmission and agglomeration. The Matthew effect of the economic network is obvious, characterized by strong homophily at the core and weak heterophily at the periphery; the traffic network tends to experience three-dimensional development, showing local robustness and regional vulnerability; and the information network has highly heterogeneous resilience, showing the characteristics of flattened network structure and diversified connection paths, with a high level of resilience. (3) Deliberate attacks are significantly more damaging to network resilience than random attacks, and a hit on a core node has a greater impact on network operational efficiency than on a vulnerable node. [Conclusion] The problem of uneven regional development is particularly obvious in less developed regions, where the core city has concentrated power but a shorter radius of radiation, and cities on the periphery are not sufficiently motivated to develop. There are both similarities and differences in resilience characteristics between the three types of networks, and network resilience under different attack modes is characterized by phased changes. In order to promote the sustainable development of the region, response policies should be formulated according to regional characteristics.

For improving the corrosion resistance of oil pipes and taking into account certain economic benefits, steel with low chromium content has received increasing attention from oil and gas fields.In this paper,a high-temperature high-pressure autoclave was used to simulate the CO2 corrosion environment, for investigating the effects of temperature on the weight loss corrosion behavior and electrochemical corrosion behavior of 1Cr steel.Moreover, the morphology and composition characteristics of corrosion products on the surface of 1Cr steel at different temperatures were analyzed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD).Results showed that in the range of 60 ～120 ℃, the corrosion rate of 1Cr steel first increased and then decreased with the increase of temperature, and reached the maximum value at 80 ℃.As the temperature increased further, the corrosion product film became denser and more uniform,which increased the charge transfer resistance.At the same time,the enrichment of Cr in the product film at high temperatures also increased the resistance of the corrosion product film, which eventually led to a decrease in the corrosion rate of 1Cr steel at 100 ℃and 120 ℃.

Sludge blending has become one of the means to transform the energy structure of coal-fired power plants. Based on the existing coal-fired flue gas system of Zhejiang Jinhua Ningneng Thermal Power Plant, this paper proposed to add activated carbon injection purification technology in the flue gas system. Based on Fluent simulation and analysis, the numerical simulation analysis of the uniformity of the spray distribution of activated carbon in the flue gas was conducted from three aspects, such as the position of the spray point of single and multiple holes, the spray angle, and the mass flow rate of the spray, and the impact and safety of the activated carbon spraying system applied in the field of flue gas treatment were analyzed. The results showed that compared with single-nozzle injection, multi-nozzle injection could make the activated carbon distribution more uniform, but the cost was higher. For single-nozzle spraying, when the location of the spraying point was at the center of the section from the horizontal elbow to the exit of the vertical elbow, the diffusion effect was good and the activated carbon had a long retention time. The economic efficiency was the highest when the spraying angle was selected to be parallel to the flue gas flow and the mass flow rate was selected to be 10 kg/h. For multiple-nozzle spraying, the adsorption effect of the activated carbon was better when the mass flow rate was selected to be 15 kg/h, but the cost was higher. Whether it is single-nozzle injection or multi-nozzle injection, parallel flue gas flow was chosen as the angle of activated carbon injection, in which the diffusion area was relatively large, the diffusion effect of activated carbon was relatively good, and the distribution was relatively uniform in the cross-section. The application of activated carbon injection system in the field of flue gas treatment has less impact on the environment and the safety is within the controllable range.