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Understanding the vibration response patterns of aircraft taxiing under runway roughness excitation is crucial for aircraft design and runway performance evaluation. In this paper, we establish pavement roughness models for both asphalt and concrete surfaces, taking into account their unique structural characteristics. We construct a six-degrees-of-freedom aircraft model using multi-rigid-body system dynamics theory and employ the pseudo-excitation method to examine the influence of pavement roughness types on the steady vibration response of aircraft taxiing at constant speeds. Furthermore, we analyze the non-stationary vibration response patterns of aircraft during takeoff and landing taxiing using the method of instantaneous frequency response function with space frequency. Lastly, we explore the effect of stochastic structural parameters on aircraft vibration response using the Monte Carlo method. Our findings reveal that the roughness power spectrum differs between asphalt and concrete pavements, and the established roughness models in this paper demonstrate a strong fit (R2 > 0.95). The type of pavement roughness has a relatively minor impact on the power spectral density distribution of the aircraft vibration response, suggesting that the same roughness model can be used for both asphalt and concrete pavements when high accuracy is not required. The power spectral density distribution of aircraft vibration response varies across different motion attitudes, with the vibration response during landing being significantly larger than that during takeoff. Among the aircraft structural parameters, the randomness of the sprung mass has the most substantial effect on the aircraft vibration response, potentially causing the variation coefficient of dynamic load on the front landing gear to exceed 0.11. Tire stiffness comes next, which can lead to the variation coefficient of dynamic load on the main landing gear reaching 0.07. The results have a guiding role in optimizing aircraft structure design and ensuring pavement performance.

Graphite carbon nitride nanosheets (g-C3N4NSs) exhibite excellent electrochemiluminescence (ECL) performance and good film-forming properties. In this paper, g-C3N4NSs were used as an ECL material to be fixed on a glassy carbon electrode(GCE). A molecularly imprinted polymer (MIP) was prepared by molecular self-assembly with chlorpyrifos (CPF) as template molecule and methacrylic acid (MAA) as functional monomer. The polymer was then introduced into g-C3N4NSs modified electrode to construct a MIP-ECL sensor. After removing the template molecule, the sensor can specifically recognize CPF. Based on the specific recognition and quenching effect of CPF on the ECL signal of g-C3N4NSs, the high sensitive and selective detection of CPF was achieved. The sensor shows a linear response to CPF in range of 1.0×10-8-1.0×10-4 mol·L-1 and limit of detection (LOD) of 5.0 nmol·L-1. It was used to detect CPF residues in vegetables and the results were satisfactory.

Geophysics offers an important means to investigate the physical processes occurring inside the earth. In particular, since the 1960s, electromagnetic (EM) methods have played important roles in mineral exploration and engineering investigation. Such investigation requires extensive data acquisition and experimental analysis based on geophysical techniques. However, high-performance geophysical equipment, particularly EM exploration equipment, has been dominated by large geophysical companies from the United States, Canada, Germany, and other European countries for decades. This has limited the development of deep exploration technology in China. Recently, we have developed a high-resolution acquisition system with a wireless control unit and a high-power transmitting system for surface EM prospecting (SEP). The new system has been tested in the high-intensity, noisy environment in Jian-sanjiang area, Heilongjiang Province. We then conducted a field survey on the western edge of Qaidam Basin, Qinghai Province. A highly conductive anomaly was found in the upper mantle below the Qinmantage Mountains, which indicates a possible northward fluid channel that runs from below the Qinmantage Mountains to the bottom of the western crust of the Qaidam Basin. Identification of this significant feature was made possible by the new SEP for its better resolution than the previous systems. Also, geophysical analysis confirmed that the thick Cenozoic sediments of the Qaidam Basin are underlain by rigid Precambrian basement rocks and are characterized by a series of folds. The resistivity profile indicates that the Qaidam Basin was formed due to the folding structures in the northern part of the Qinghai-Tibet Plateau which provided an additional evidence for the uplifting of the Qinghai-Tibet Plateau.

北海道大学観光創造フォーラム「ネオツーリズムの創造に向けて」. 平成20年2月29日～平成20年3月3日. 札幌市. 「ヘリテージツーリズム」セッション『ヘリテージツーリズムをめぐる新視点～日中双方の視点から：建築遺産から無形文化遺産まで』. モデレータ：山村高淑. 平成20年3月2日.