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Problems of large settlements and uneven settlements on the road always happen during service stage. Reinforced embankments can reduce these problems. But currently the study on the mechanical properties of reinforced embankments during service stage are so few, and lack of measured data. This study uses numerical simulation and on-site measured data analysis to set up a geogrid creep damage model and traffic load model. Based on the analysis of the mechanical properties of reinforced embankment under the conditions of new test section and widening test section, the influence laws of traffic load amplitude, frequency and driving interval on reinforced embankment are obtained. When the traffic load amplitude is 2q0, there is little difference in settlement between the two test sections, but the settlement ratio gets the maximum value of 0.028 mm/d when the amplitude is 2q0. When the traffic load frequency increases from 1 Hz to 4 Hz, the embankment settlement is in the sudden settlement stage, and the settlement is almost stable after 4 Hz. When the driving interval is greater than 4 s, the rebound value and rebound time are almost stable.

In this paper, a calculation method for the tangential velocity solution of radar target based on linear vector method is proposed. It makes full use of the advantage of high precision radial velocity measurement of radar, and realizes the accurate computation of tangential velocity of radar target. Based on the actual measurement capability of continuous wave (CW) radar, the accuracy of the tangential velocity is analyzed. The feasibility of calculation method and accuracy analysis method is verified by simulation experiment and measured data of shooting range.

Every disaster outbreak in human history has either implicitly or explicitly promoted literary creation. The new epidemic sweeping today has become a great catastrophe common to all humankind since the new century. Under the epidemic, what does literature do? It is an inevitable question that must be answered in the post-epidemic era of literary transformation. Therefore, this paper, while feeling grateful for literature’s eagerness to respond to the call of reality and intervene in human psychological healing, creatively uses the concept of human destiny to look at the empirical and theoretical expansion of disaster narratives, explores the comprehensive and diversified expression of such “epidemic” themes in literary creation, and considers how to write about disasters while taking into account aesthetics In addition, we explore the comprehensive and diversified expressions of such “epidemic” themes in literary creation, and consider how disaster writing can take into account the three essential dimensions of individual trauma, collective experience, and identity construction while taking into account aesthetics, to continuously rewrite and even expand the connotation of epidemic literature and actively promote the literary turn in the post-epidemic era.

AbstractThe wet desulfurization yields slurry with a moderate temperature and stable supply and thus holds promise for waste heat utilization. However, the corrosive nature and solid particle content of desulfurization slurry from the wet desulfurization process pose potential erosion challenges in waste heat utilization heat exchangers, which is an aspect scarcely explored in the existing literature. The present study aimed to investigate the erosion characteristics in desulfurization slurry heat exchangers using numerical simulation approaches, which can offer crucial insights for practical application in low-grade energy recovery. The result identified slurry mass flow rate and composition as essential factors of erosion distribution. Higher mass flow rates enhance heat transfer efficiency. Still, paradoxically, lower flow rates lead to more pronounced erosion, with a slurry mass flow rate of 35 kg/s resulting in nearly double the erosion compared to the benchmark condition of 56 kg/s. This phenomenon is ascribed to lower fluid velocities in the heat tubes, where the influence of changed velocity diminishes, but slurry exhibits more stable flow at higher mass flow rates. Furthermore, it is also observed that both elevated solids content and particle size lead to an increase in erosion rates. The difference in erosion caused by solid particles with particle sizes in the range of 200–350 µm is marginal. The heat exchanger structure and arrangement also impact fluid flow and erosion. While the difference in fluid flow between vertically and horizontally arranged heat exchangers is negligible, the erosion was significantly reduced to 1/10 in the vertical arrangement. The no-tube-in-window heat exchangers, designed to minimize vibration, exhibit reduced heat transfer capacity alongside diminished and more uniform erosion. The augmentation of tube passes reduces overall erosion but focalizes severe erosion at the slurry inlet, which presents a potential design solution. [ABSTRACT FROM AUTHOR]

Tar-rich coal holds the potential to substitute the supply of oil-gas resources. The in-situ pyrolysis contributes to efficient resource utilization and can potentially achieve net-zero CO2 emissions. However, it is challenging to efficiently separate oil-gas resources, which are predominated by tar, from multiphase products of in-situ pyrolysis of tar-rich coal. Additionally, the difference in fluid properties yields significant influences on separation performance, while the understanding of the separation characteristics of high-viscosity fluid remains insufficient. In this study, the separation process of pyrolysis products from tar-rich coal was investigated using the computational fluid dynamics simulation approach. The flow field, pressure drop, separation efficiency and distribution characteristics were analyzed. The simulation results indicate that the volute cyclone separator exhibits commendable separation efficiency, exceeding 98%. Meanwhile, in handling tars containing a high concentration of light oil, the separator demonstrates remarkable adaptability. The separation efficiency of solid particles decreases from 89% to 83% when the system contains a high content of pitch. The particle diameter exerts great influence on the flow field. The separation efficiencies are 99% and 0.37%, respectively, when the particle sizes are selected as 0.1 mm and 0.001 mm. In the scope of this study, the optimal working conditions of the cyclone separator were determined, which provides data support for improving the separation efficiency and recovery rate of the oil-gas resources. [ABSTRACT FROM AUTHOR]

In order to study the influence of discharge parameters on the electric spark deposition process, an automatic electric spark deposition device is built by a closed-loop control system of discharge parameters. An automatic electric spark deposition test is carried out at different control voltages. By analyzing the effective discharge waveform parameters, transfer efficiency, deposition efficiency, contact force in the deposition process, surface morphology, and cross-sectional morphology of the deposition layer under different control voltages, etc. Analysis of the results shows that changing the control voltage has a direct effect on the number of discharge types in the deposition process. With the appropriate control voltage, better transfer efficiency and deposition quality can be achieved. Contact discharge has a greater effect on material transfer efficiency than other types of discharge. The transfer of the electrode to the material on the workpiece is mainly achieved by contact discharge. Automatic control of discharge parameters can also be applied to automatic control of discharge pulse types. [ABSTRACT FROM AUTHOR]

Background High tumour budding has been indicated as a risk factor of poor survival in colorectal cancer. This study aimed to investigate the impact of tumour budding grades and the use of adjuvant chemotherapy on prognosis in patients with colorectal cancer. Methods This study included consecutive colorectal cancer patients who underwent radical surgery for primary colorectal adenocarcinoma at The Sixth Hospital of Sun Yat-sen University between 2009 and 2019. Tumour budding was assessed based on the recommendations of the International Tumor Budding Consensus Conference using haematoxylin and eosin (H&E)-stained slides with tumour samples. The primary outcome of interest was to correlate tumour budding with disease-free survival and overall survival; the secondary outcome was investigation of the impact of adjuvant therapy on different tumour budding grades. In addition, a subgroup analysis was performed for the effects of lymphocytic infiltration on adjuvant chemotherapy in patients with Bd3. Results Of 709 eligible patients, 412 with colorectal cancer were included. According to the International Tumor Budding Consensus Conference, 210 (50.9 per cent), 127 (30.8 per cent) and 75 (18.2 per cent) were classified as low budding (Bd1), intermediate budding (Bd2) and high budding (Bd3) respectively. Patients with Bd1, Bd2 and Bd3 had 5-year disease-free survival rates of 82.9 per cent, 70.1 per cent and 49.3 per cent respectively, and 5-year overall survival rates of 90 per cent, 79.5 per cent and 62.7 per cent respectively (P <0.001). Adjuvant chemotherapy yielded a significant survival benefit in patients with Bd3 (5-year disease-free survival, 65 per cent versus 31.4 per cent, P <0.001; 5-year overall survival, 84.4 per cent versus 63.1 per cent, P <0.001), but not in those with Bd1 or Bd2. In patients with Bd3, the benefit of adjuvant chemotherapy was maintained in those with low, but not high lymphocytic infiltration. Conclusion High grade of tumour budding was strongly correlated with poorer survival outcomes in colorectal cancer. Patients with Bd3 benefited from adjuvant chemotherapy, with the exclusion of patients with high lymphocytic infiltration. [ABSTRACT FROM AUTHOR]

Cofiring sludge with coal based on existing power plants is a promising method to realize harmless recycling treatment for sludge disposal. However, the influences of sludge addition on NOx emission are still controversial. Moreover, the optimal operating strategies for the cocombustion boiler need further investigations. In this study, the influences of sludge blending ratio, moisture content, sludge inlet position, and air-staging parameter on the combustion characteristics and NOx emission behaviors in a 330-MW boiler were analyzed numerically. The results show that with the increase of sludge blending ratio, the flue gas temperature in the primary zone decreases. The overall burnout ratio declines with the addition of sludge due to the higher ash and moisture contents. Although the sludge contains more N than coal, the NOx emissions in the cofiring case are lower than those in the coal-fired case due to the lower temperature and stronger reducing atmosphere in the primary zone. Reducing the moisture in the sludge is beneficial to the combustion within the furnace. Nevertheless, because of the higher temperature and lower CO concentration within the furnace, the NOx concentration at the furnace outlet increases. For wall-fired boilers, feeding the sludge from the lower burners should be avoided considering the potential surge in NOx emission. When the excess air ratio in the primary zone increases from 0.74 to 0.96, the NOx concentration at the furnace outlet rises by 58%. Hence, although relatively lower excess air ratio in the primary zone could bring adverse impacts on the burnout behaviors, air-staging combustion is still necessary when cofiring sludge in the coal-fired boiler. [ABSTRACT FROM AUTHOR]