In order to study the influence mechanism of energetic particles on the combustion and explosion reaction of solid-liquid mixed fuel, a 20 L spherical cloud combustion and explosion characteristics test system was used to study the combustion and explosion characteristics of solid-liquid fuel-air dispersion systems with different mass fractions of energetic substances. Under low concentration conditions, the explosion pressure, maximum pressure rise rate, reaction time and explosion lower limit of different fuels were measured. Based on the combination of solid-liquid dispersed particles, the impact of energetic particles on the combustion and explosion characteristics of solid-liquid mixed fuel was analyzed. The results show that in the 1,3,5-trinitroperhy-dro-1,3,5-triazine(RDX)/aluminum powder mixed fuel system, the explosion pressure and maximum pressure rise rate first increase and then decrease with the increase of RDX mass fraction, with the maximum values being 1 516.17 kPa and 116.17 kPa/ms respectively. For RDX/ aluminum powder/nitromethane mixed fuel system, the addition of RDX causes the explosion pressure to continuously decrease, reaching 427.99 kPa. When the RDX mass fraction is low, RDX inhibits the combustion explosion of the mixed fuel. At the same time, it was found that the change pattern of mixed fuel reaction time is completely opposite to the change pattern of maximum pressure rise rate.

The study of diagenesis of shale is an important part of the analysis of diagenesis system, pore structure and formation overpressure. Based on the data of X-ray diffraction, logging curve and measured porosity, the transformation amount of clay minerals in the hinterland of Junggar Basin was quantitatively analyzed. Combined with temperature, logging curve and porosity, the diagenetic evolution stage of shale was determined, and the mechanism of overpressure development was discussed. The study shows that the diagenetic evolution of shale in the hinterland of Junggar Basin can be divided into three stages. At the dominant stage of mechanical compaction from 0 m to 2 400 m, the clay mineral content in this stage is mainly affected by sediment sources, and the content and conversion amount have little change. The porosity calculated by acoustic logging is slightly larger than that calculated by density logging. The sonic time difference (AC), density (DEN) and compensated neutron (CNL) curves all decrease, while the resistivity (RT) curves increase. From 2 400 m to 4 200 m, during the transition stage between chemical compaction and mechanical compaction, illite-montmorillonite mixed layer began to transform into illite and chlorite, and the porosity calculated by density logging is equivalent to that calculated by acoustic logging. The curve of AC, DEN and CNL decreases slowly, and the RT curve slightly reverses. Below 4 200 m, in the dominant stage of chemical compaction, clay minerals begin to transform in large quantities, and feldspar begins to dissolve in large quantities. With the increase of depth, temperature and pressure gradually increase. When the temperature reaches about 120 ℃, kaolinite transforms into illite, and the content of potassium feldspar drops to almost 0%. The porosity calculated by density logging slightly deviates from the normal evolution trend, while the porosity calculated by sonic logging significantly deviates from the normal evolution trend, and the AC, DEN, CNL and RT curves all invert. Chemical compaction is one of the main causes of overpressure in the study area.

To promote occupational health and prevent musculoskeletal disorders among occupational drivers, the current status of functional movement ability of professional drivers was evaluated through functional movement screen (FMS), and the effect of exercise intervention was further explored. A stratified convenience sampling method was utilized to select 145 occupational drivers as participants, with their functional movement abilities rigorously evaluated using the FMS. Subsequently, 20 female drivers underwent an exercise intervention, with their exercise load monitored throughout, followed by a post-intervention FMS assessment. SPSS 29.0 software was used to analyze the FMS results, gender differences, and the effects of the exercise intervention. The results show that the FMS total scores of occupational drivers are generally below 14 points. Among the individual tests, the active straight leg raise scores highest, while the in-line lunge scores lowest. Gender differences are found in the scores for deep squat, hurdle step, active straight leg raise, and trunk stability push-up movements (P<0.05). Post-intervention, the basic functional movements, lower limb flexibility, and trunk stability patterns of female drivers show significant improvement, with all differences being statistically significant (P<0.05). The exercise intervention load is generally classified as moderate-intensity aerobic exercise. It is concluded that the functional movement capacity of occupational drivers is generally inadequate, and moderate-intensity exercise intervention is an effective means to improve the functional movement capacity of female drivers and prevent musculoskeletal disorders.

Reliability analysis and allocation were conducted on the propulsion system of multi rotor electric vertical takeoff and landing (eVTOL) aircraft. Firstly, to solve the problem of insufficient accumulation of reliability historical data of multi-rotor eVTOL aircraft, a reliability analysis model was established by using fuzzy Bayesian network (FBN) to supplement the reliability prior data, and reliability posterior inference was carried out to assist the key link of the positioning system. Secondly, based on the FBN reliability analysis model of the system, an improved advisory group on reliability of electronic equipment(AGREE) reliability allocation method was proposed. Reliability distribution of eVTOL propulsion systems with different configurations was carried out. The results show that the FBN reliability analysis model supplements the propulsion system reliability data and can effectively identify the system weak links. The reliability allocation results of the improved AGREE allocation method meet the reliability requirements for eVTOL aircraft in SC-VTOL-01, while the reliability allocation results obtained by this method are more reasonable, reflecting the differences between different configurations, subsystems, and components.

Hyperspectral remote sensing widely uses unmanned aerial vehicles (UAV) as flight platforms for data collection, which has the advantages of flexibility and efficiency. However, due to UAV performance and environmental conditions, it is difficult for sensors to maintain a fixed shooting posture during the collection process, resulting in data misalignment, distortion, and deformation. While UAV positioning systems and inertial measurement devices provide real-time position and posture for hyperspectral cameras, achieving high accuracy often necessitates numerous ground control points for auxiliary geometric correction, which is time-consuming and labor-intensive. Therefore, it is necessary to study an efficient and time-saving data processing method to correct distortions in hyperspectral data acquisition. In order to efficiently and time-saving eliminate distortions in hyperspectral data during the acquisition process, an unmanned aerial vehicle (UAV) push scan hyperspectral camera data acquisition system was designed based on the principle of collinearity equations. The system integrates a high-precision inertial measurement system and synchronously collects LiDAR point cloud data in the measurement area. The high-precision terrain information contained in the LiDAR point cloud was used for geometric correction of hyperspectral data, and the influence of different density point cloud data on the geometric correction results was studied. Experiments have shown that using LiDAR point clouds improves accuracy by 67% compared to using average elevation geometric correction results. The use of LiDAR and hyperspectral cameras for synchronous acquisition has a significant effect on improving the accuracy of hyperspectral data.

The oxidation of Sb(III) occurred rapidly in aerobic and dark groundwater environments, with previous studies suggesting that co-oxidation of Fe(II) and Sb(III) may be the predominant driving mechanism. However, there is a lack of field evidence confirming environmental isotope fractionation. Therefore, 20 groups of Magunao aquifer (${\mathrm{Dx}}_{3}^{4}$ water) samples were collected from the North mine of Xikuangshan antimony mining area in Hunan Province to compare the differences in environmental isotopes (δ⁵⁶Fe, δ¹³C, and δ³⁴S) between high- and low-Sb groundwater and investigate the fractionation process of these isotopes. The results reveal that total Sb(^TSb) concentrations ranged from 5.30 μg/L to 20 700 μg/L, with a mean concentration of 3 660.61 μg/L. Additionally, Sb(V) is found to be the most dominant valence state for Sb in ${\mathrm{Dx}}_{3}^{4}$ water. The neutral-alkaline and oxygen-enriched conditions in ${\mathrm{Dx}}_{3}^{4}$ water facilitate the co-oxidation of FeS₂ and Sb₂S₃, as well as induce fractionation of δ¹⁸${\mathrm{O}}_{\mathrm{S}{\mathrm{O}}_{4}}$, δ³⁴${\mathrm{S}}_{\mathrm{S}{\mathrm{O}}_{4}}$and δ⁵⁶Fe between sediments and groundwater, resulting in the increase of $\mathrm{S}{\mathrm{O}}_{4}^{2-}$,total Fe (^TFe) and Sb(Ⅴ) contents in high Sb groundwater. Furthermore, microbial activities promote the oxidative decomposition of organic carbon, thereby enhancing the co-oxidation rate of Fe(Ⅱ) and Sb(Ⅲ). This conclusion unveils a novel mechanism for aerobic oxidation of Sb(III) in dark groundwater environments while providing a scientific foundation for advancing our understanding of the Sb geochemical cycle and preventing environmental pollution from high Sb groundwater.

In order to further explore the pipe-soil interaction and the failure mechanism of buried pipelines during the collapse process, the element birth and death technology and the displacement load technology were used to simulate the soil collapse process. The coupling models considering the pipe-soil nonlinear effect were constructed respectively to analyze the failure law of buried pipelines under collapse. The results show that the bottom of the pipe jacking is the control point, the axial stress is the control stress, and the junction of the non-subsidence area and the subsidence area and the center of the subsidence area are dangerous sections. Applying displacement load technology to element birth and death technology, the location of the most dangerous section transitions from the junction of non-subsidence area and subsidence area to the center of subsidence area, and the peak value of Von-Mises stress increases from 4.3 MPa to 6.09 MPa. The application of displacement load technology makes the lower part of the pipeline always in contact with the soil, and the pipeline is subjected to strong shear near the junction of the non-subsidence area and the subsidence area. The element birth and death technology is lost with the soil, and the pipe-soil state gradually changes from contact to separation, which is a weak shear effect. The Von-Mises stress peak is larger and the radial stress is smaller, which can better reflect the actual situation. According to the stress and settlement values, the maximum Von-Mises stress prediction formula is fitted, and the error is within 7%. The research results can provide reference for the safe operation of pipelines and the selection of collapse simulation methods.

The prediction of dynamic stress-strain relationship of composite geomembrane is one of the key problems involved in the long-term operation of seepage prevention projects of earth-rock dams. In order to study the effect of cyclic loading on the stress and strain of the composite geomembrane, cyclic loading and unloading tests were carried out under three different stress levels of 10%, 20% and 30%, and the creep tests under 10% to 80% stress levels were carried out to compare and analyze the creep and creep recovery characteristics of the composite geomembrane. The expression of strain under cyclic loading and accumulation condition was presented, and the constitutive model of composite geomembrane boundary surface under cyclic loading condition was constructed. The results show that the deformation of composite geomembrane increases instantaneously at the moment of loading and unloading, and then gradually slows down with the increase of time. After complete unloading, when the stress level is less than 30%, the deformation of the composite geomembrane can almost recover. When the stress level is greater than or equal to 40%, the residual deformation increases gradually with the increase of the stress level. The effect of cyclic loading times on the creep deformation of geomembrane is not a simple linear relationship. In addition, an improved three-parameter viscoelastic model was established, and it is verified that the model can reproduce the creep recovery process of composite geomembrane under different load levels. The research results can provide a reference for the long-term deformation analysis of composite geomembrane in earth-rock dams.

In order to explore the dust deposition characteristics on the surface of photovoltaic(PV) modules. For the dust accumulation problem of ground-mounted photovoltaic, the deposition characteristics of dust particles with different particle sizes were investigated from two factors, namely, tilt angle and wind speed, by using CFD numerical simulation method. The results show that as the tilt angle of the PV module increases, the deposition rate of dust on the surface of the PV module gradually decreases, in addition, it is found that when the PV module is facing the wind, the rate of dust deposition increases with the increase of wind speed, and the maximum particle size of dust deposition will become larger with the increase of wind speed. At the same time, with the increase of particle size, the deposition of dust on the surface of the PV module is the first to increase and then decrease. The study is of great significance in solving the problem of dust accumulation in photovoltaic power plants.

Aiming at the unmanned autonomous positioning task of mobile robot during the maintenance of nuclear reactor internals, an underwater geometric positioning method combining inertial measurement unit(IMU) and monocular visual distance measurement was proposed. Combining with the actual environment demand, the principle of distance measurement with monocular camera was described briefly. Aiming at the limitation of the underwater nuclear radiation environment on the use of sensors, a method based on monocular vision correction of inertial measurement unit position estimation integral error and geometric positioning was proposed. Simulation experiments show that the positioning method can effectively correct the accumulated error generated in the positioning process of the inertial measurement unit, and improve the positioning accuracy of the robot in underwater motion.