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A deep foundation pit in a station of the Hangzhou subway is adjacent to new high-rise residential buildings on the north side and to the Evergrande foundation pit being excavated on the south side. This work considers the excavation of the foundation pit in the subway station as the research subject, focuses on the difference of the deformation and Earth pressure between the north side and the south side of the foundation pit under these special working conditions through the analysis of the measured data, and compares it with an ordinary foundation pit. Analyzing the measured data reveals that the horizontal displacement of the retaining wall and the ground settlement are far larger on the north side than on the south side, and both often exceed the deformation alarm value; the deformation of the ordinary foundation pit is between the deformation of the overloaded (north) side and that of the unloaded (south) side of the foundation pit. Moreover, the maximum rate of the horizontal creep of the soil and the maximum rate of the creep caused by the ground settlement on the north side of the foundation pit are larger than those on the south side of the foundation pit; the maximum rate of the horizontal creep of the ordinary foundation pit is between the two. The active Earth pressure on the pit wall on the north side is higher than that on the south side of the foundation pit, and because of the surrounding unloading, passive Earth pressure is generated at the bottom of the pit wall on the south side of the foundation pit, which causes it to shift to the outside of the foundation pit. The settlement of the surrounding high-rise buildings and the settlement of the columns are all within the range of the alarm values; also, the buildings settle evenly. Due to the excavation and unloading on the south side of the foundation pit, the uplift of the columns is not considerable.

The inner ears of fish contain three pairs of otoliths—lapilli, asterisci and sagittae—which play important roles in hearing and balance. However, acoustic properties and dynamic responses of fish otoliths are poorly understood. The large yellow croaker (Larimichthys crocea), like many species in the family Sciaenidae, is extremely sensitive to sound. The present study used L. crocea sagittae as the research subject and examined the variation in shear stress on sagittae under different acoustic stimuli. For the first time, the sound speed of the sagitta was measured using ultrasonic pulse-echo techniques, and the acoustic impedance and natural frequency of the sagitta were calculated. Larimichthys crocea adults (20–22 cm standard length, n = 10) had a sagitta density of 2781.5 ± 28.06 kg/m3, sound speed of 4828–6000 m/s and acoustic impedance range of 13.4–16.7 MPa·s/m, approximately 9–11 times that of seawater (1.48 MPa·s/m). The natural frequency of the sagitta was 76.4–95.5 kHz. The shape and structural details of sagittae were reconstructed by 3D scanner and the shear stress responses of sagittae under different acoustic stimulus were investigated based on a finite element model. The simulation results showed that the shear stress responses tended to increase and then decrease in the range of sciaenid hearing frequency from 200 to 1300 Hz, peaking at 800 Hz. The shear stress responses varied with the direction of acoustic stimulus and peaked when the incident direction was perpendicular to the inner surface of the otolith. These results provide important parameters that may be used to protect L. crocea from possible underwater noise damage, particularly during their spawning aggregations and over-wintering aggregations.

A 21-year-old Chinese woman was referred to our department for the swelling and toothache of the right lower posterior teeth for 2 days. Clinical and Panoramic and CT image examination revealed that the third molar near middle impacted, and the third molar of right maxillary distoangular impacted.We all know that the mandible impacted third molar usually impossible to erupt. However, the right mandible near middle impacted third molar erupted after 7 months. The panoramic image confirmed that the right mandible impacted third molar had become vertical and had good contact with the adjacent second molar. Therefore, reported as a rare case. Keywords: Mandible, Impacted third molar, Vertical, Reason, Pericoronitis.

The article expounds the principle, steps and results of detecting the fire source by the magnetic method. Based on the determination of the fire source range, by analyzing the actual situation of the shallow coal seam, comparing the advantages and disadvantages of the three different treatment methods and the applicable situation, a stripping is proposed. The law governs the fire zone and applies it in the governance zone. The results show that the magnetic detection technology has high detection accuracy and fast efficiency, and the stripping method has good fire extinguishing effect in the fire area, high safety, large amount of residual coal recovery, and is suitable for shallow buried fire sources. The study provides a scientific basis for fire detection, treatment, coal resource recovery, environmental protection and economic development in open-pit mine fire areas.

It was proposed to use CO2/N2 to effectively prevent and control Class A solid spontaneous fires such as coal. The preparation process of CO2/N2 cryogenic slurry pipeline and its pipeline flow characteristics were studied. The temperature field, pressure field and phase change characteristic changed during the transportation of the CO2/N2 mixture in the pipeline are analyzed by numerical simulation. The results showed that: the fluid in the pipeline exchanged heat and started to contact at a position of 0.1m in the pipeline. The temperature first rapidly dropped to the lowest temperature of 103K, and then the fluids in the range of 0.1m to 0.3m were fully mixed, and the temperature rised to 164K. The temperature was consistent with the equilibrium state in the pipe, and the temperature was gentle and stable; the pressure in the pipe was on the whole downward trend, and each position along the main pipe produced a positive pressure difference relative to the end of the pipe. The closer to the mixing place, the greater the corresponding pressure difference; During the mixing process, LN2 was acted as a cold source to sublime CO2 to form dry ice particles. And through the cryogenic fluid mixing experiment, the temperature distribution in the pipeline, range of the dry ice particle generation position, and the dry ice particle generation phenomenon was measured. The results showed that the mixing was completed within 0.8 m of the pipeline, and the temperature in the tube rised to 168K and remain stable. The data were basically consistent. And dry ice particles generated at the temperature of 194.5K, and a diffuse gas cloud formed at the outlet with the momentum of the jet.

In order to alleviate the serious congestion in the evacuation process of high-rise buildings in today’s society when a fire occurs, a hotel building in Xi’an was used as the background in this research process, and the disaster escape software Pathfinder was used to conduct a fire on all personnel in the hotel. The subsequent evacuation simulation shows that different behaviors and different groups of people need to spend time in the process of escape and the actual situation of the stairs, walkways, safety exits and other locations in this situation. Combined with the comparative analysis of the required evacuation time and evacuation width of the building in the “Code for Fire Protection Design of Buildings”, it is determined that the fastest evacuation of people can be carried out in 657s.

Spontaneous combustion of coal seams in goaf seriously threatens the development of the coal mining industry. The prediction of goaf temperature is of great significance for mine disaster prevention. Based on the energy conservation equation of floating coal in goaf, the analytical solution of the steady-state temperature field in goaf is derived in this paper, and the temperature of goaf can be calculated simply through a series of physical and chemical parameters. This method is applied to Kaida Coal Mine to calculate the temperature of goaf at the return air side of 46205 working face. The results show that although there is some error between the calculated value and the measured value of the temperature in goaf, the predicted results can reflect the change rule of the temperature in goaf, and provide some guidance for the prevention and control of coal spontaneous combustion in goaf. With the increase of buried depth, the floating coal temperature rises first and then decreases. It is estimated that the maximum temperature of goaf is 27.11 °C, which is located 25m deep in goaf.