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Aiming at the frost heave characteristics of long-distance and large-section underground freezing projects in cities, the double-line tunnel of Shanghai Metro Line 18 undercrossing an operation station was select as an example,a three-dimensional numerical model was established by using finite element software based on the thermal-mechanical coupling equation. Combined with the physical parameters obtained from laboratory tests, the evolution law of frost heave displacement field of the project was studied, and the influence of measures such as the staggered peak freezing and the adjustment of brine temperature on the frost heave displacement field was explored. Under the experimental conditions, the results show that: ① the deformation of the station floor caused by frost heave which mainly occurs in the active freezing period. When the double-line tunnel is frozen at the same time, the vertical displacement of the station floor at 45days of freezing reaches 77.72% of the displacement at 90 days of freezing. ② When the freezing time reaches 90 days, compared with simultaneous freezing, the displacement of the station floor reduced by 7.7% under the condtion of staggered peak freezing. The superposition effect of frost heave in the same time period is effectively avoided, and the frost heave effect is reduced to a certain extent. ③ When the freezing time reaches 90 days, compared with simultaneous freezing, the displacement of the station floor reduced by 34.2% under the condtion of adjusting the brine temperature, it shown that the expansion rate and frost heave effect of frozen soil are effectively controlled. In engineering practice, measures such as staggered freezing and adjusting brine temperature are used together to control frost heave, and the maximum vertical deformation of the station floor is 25.41 mm. The deformation law of the station floor obtained by numerical simulation is basically consistent with the measured data, which effectively guided the construction of the project.

Purposes Owing to the varietry of electrical equipment and the complex connection between them in transformer station, there are many common problems includeng relatively limited location and picture contrast of equipment, insufficient target images and markers in practical applications, and inaccurate electrical equipment image segmentation brought by the traditional way. In this paper, CNN (Convolutional Neural Network) is combined with Transformer to form a new model for segmentation of electrical equipment, and a new SE-Transfomer (Substation Equipment Transformer) network based on codec structure is proposed. Methods To obtain the local context information, the coder extracts the spatial feature map by using CNN at first. Meanwhile, the feature map is carefully modified with multi-scale feature inputs for global feature modeling. The decoder extracts global deep features using Transformer and performs stepwise up-sampling to predict the detailed segmentation map. SE-Transfomer is extensively experimented on the dataset of Liangjiazhuang Transformer Station in Shanxi province, and its longitudinal results of Dice, Recall, Specificity, and RMSE (Root Mean Square Error) are 89.31%, 90.52%, 89.62%, and 11.32, respectively. Findings The results indicate that SE-Transfomer obtains comparable or higher results than previous state-of-the-art segmentation methods on the scanning of electrical equipment in the transformer station.

The paper comprehensively summarizes the process of China's coal mine construction technology from introduction and absorption to independent development since the founding of New China more than 70 years ago, as well as the important achievements in basic research, process innovation, technological breakthrough, equipment development and achievement transformation, involving drilling and blasting method, freezing method, grouting method, drilling method, caisson method and other drilling technology as well as coal mine rock tunneling technology. At present, the mechanization and automation level of drilling and blasting equipment mainly for drilling and blasting rock has been significantly improved, and the comprehensive drilling technology for short-segment excavation of kilometer-level deep wells has been mature, and the maximum depth of vertical shaft drilling has reached 1341.6 m.The level of geological support technology for drilling and tunneling such as freezing method and grouting method has been significantly improved, gradually replacing the curtain method, sheet pile method and dewatering method and other drilling technology. The maximum frozen depth of vertical shaft is 990 m, and the maximum frozen section of inclined shaft is 681 m. The longest inclined shaft of 5875 m is built by working face grouting, and the ground pre-grouting reinforcement depth is 1355 m.Breakthroughs have been made in the technology of mechanical rock breaking and tunneling. The maximum drilling diameter of reverse drilling rig is 6 m, and the maximum drilling depth is 562 m.The maximum drilling diameter of vertical drilling rig is 10.8 m, and the maximum drilling depth is 660 m, and the application range is gradually expanded. The drilling method of vertical tunneling machine has achieved a breakthrough of zero, which has laid a foundation for intelligent drilling of coal mine vertical shaft. The operation line of the mechanized excavation method of the rock tunnel has been formed, and the average tunneling speed of the full section tunneling machine is more than 400 m/month. In summary, the innovation and development of coal in China mine construction technology and equipment in the past 70 years has significantly improved the operation environment, construction efficiency and safety level of the coal mine tunneling, realized the unmanned and fully mechanized operation of the tunneling working face, solved the problems of the tunnel construction in each stage of coal development in China, and ensured the basic construction and mining continuous construction of coal mines. At the same time, the technical equipment developed from the coal mine construction and the successful experience have been promoted and practiced in the underground engineering fields such as hydraulic power generation, municipal rail transit, mountain traffic tunnels, water diversion tunnels, and made contributions to the construction of national key projects and the development of national economy.

A multiplex real-time polymerase chain reaction (PCR) method for simultaneous and rapid detection of components derived from sweet potato, cassava, potato, and corn was established. The g3pdhs gene of sweet potato and cassava, the UGPase gene of potato and the zSSIIb gene of corn were used as target genes to design specific primers and TaqMan probe, and the 18S rRNA gene was used as the internal reference gene. Methodological validation was performed, and the proposed method was applied to simulated samples with different mixing ratios and actual starch samples. The results showed that this method was high-throughput, sensitive and specific. No cross-reaction was found with 15 non-target sources. The detection sensitivity for template DNA was 3 × 10-3 ng/μL, and the proposed method had a good linear relationship and high amplification efficiency. The detection limit for edible starch samples was 0.1%. The results of the PCR method for 50 actual samples were consistent with those of the reference method, indicating that this method could be used for the detection of common adulterants in edible starches.

为提高虾青素的生物利用度，增加其稳定性，采用均质乳化-探头超声法制备虾青素纳米脂质载体（AST-NLC）。以粒径和包封率为指标，通过单因素试验和中心复合设计法优化AST-NLC的制备工艺，并对制备的AST-NLC进行X射线衍射（XRD）和傅里叶红外光谱（FT-IR）结构表征，以及4、25、50 ℃下的热稳定性测试。结果表明:制备AST-NLC的最佳工艺条件为甘油三硬脂酸酯与中链甘油三酯质量比1∶ 11（总质量0.99 g）、乳化剂用量（吐温-80+大豆卵磷脂，质量比1∶ 1）3.8%（以水相质量为基准）、油水比1∶ 34（体积比）、均质速度5 000 r/min、超声时间2 min、虾青素添加量2.0 mg，在此条件下制备的AST- NLC粒径为（79.30±1.21）nm，多分散系数（PDI）为0.01±0.01，包封率为（81.36±1.84）%，Zeta电位为（-18.13±2.83）mV；结构表征结果表明，AST-NLC中的虾青素是以分子的状态包裹在脂质体中；热稳定性结果显示，4 ℃更有利于AST-NLC的保存。综上，成功制备了粒径小、分散均匀且包封率较高的AST-NLC。In order to improve the bioavailability and increase the stability of astaxanthin, astaxanthin nanolipid carrier (AST-NLC) was prepared by the homogeneous emulsification-probe ultrasonic method. The preparation process of AST-NLC was optimized by single factor experiment and central composite design method with particle size and encapsulation rate as indexes, and the AST-NLC prepared was structurally characterized by X-ray diffraction (XRD) and Fourier infrared spectroscopy(FT-IR) and tested for thermal stability at 4, 25 ℃ and 50 ℃. The results showed that the optimal process conditions for preparing AST-NLC were mass ratio of glycerol tristearate to medium chain triglyceride 1∶ 11 (total mass 0.99 g), emulsifier dosage (Tween-80+soybean lecithin, mass ratio 1∶ 1)3.8%(based on water phase mass), oil-water volume ratio 1∶ 34, homogeneous speed 5 000 r/min, ultrasonic time 2 min, astaxanthin dosage 2.0 mg. Under the optimal conditions, the AST-NLC was prepared with a particle size of (79.30±1.21) nm, a polymer dispersity index(PDI) of 0.01±0.01, an encapsulation rate of (81.36±1.84)%, and Zeta potential（-18.13±2.83）mV. The structural analysis revealed that astaxanthin in AST-NLC was encapsulated in liposomes in the state of molecules. The thermal stability results showed 4 ℃ was more favorable for the preservation of AST-NLC. In conclusion, AST-NLC with small particle size, homogenous dispersion and high encapsulation rate was successfully prepared.