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Copyright of Modern Preventive Medicine is the property of Modern Preventive Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Bioprocess Engineering is the property of Chinese Journal of Bioprocess Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The pre-engineering diversion project in narrow river valley with high water head, high discharge and complex geological conditions faces the issue of high speed water discharge, which requires higher energy dissipation body type. Based on hydraulic physics model test, the energy dissipation type at the outlet of diversion tunnel of a hydraulic project was optimized and explored, and four layout schemes including right bank orientation, tunnel line deviation, left bank diversion and forced energy dissipation + left bank diversion were proposed. Through the determination and comparison of hydraulic parameters such as water flow pattern, velocity and erosion characteristics, the compound energy dissipation type of forced energy dissipation + left bank diversion was finally recommended, and the adaptability of the recommended type to the large and small flow conditions was tested and analyzed throughout the diversion process. The test results show that the composite energy dissipation body type has higher energy dissipation efficiency under each working condition, the flow velocity of cofferdam and left bank near shore is obviously reduced, the dispersed water flow can effectively block backflow, the intensity of water surface fluctuation is weakened, the main flow returns to the channel smoothly, the scouring and siltation situation is good and the left bank is protected from scouring. The composite energy dissipation body type can meet the project energy dissipation, safety and stability requirements, and can provide reference for the outlet design of the diversion tunnel project with similar characteristics. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to reveal the characteristics of the velocity and pressure in the vortex drop shaft, a numerical simulation based on RNG k-ε turbulence model and VOF method was carried out for a vortex drop shaft spillway, and some test results were compared with simulation results. The results reveal that the upper part of the wall pressure of the swirling flow in vortex drop shaft is larger than that of the lower part, while the cavity pressure is the opposite. The axial velocity near the wall basically increases along the shaft, but the increase rate decreases in the vertical shaft. Additionally, the radial velocity is extremely small and can be ignored. The total flow velocity of vortex chamber and gradient section is the largest at the air-water interface, which decreases gently along the radial direction, but its distribution becomes more uniform as the water layer becomes thinner. The cavity gas moves disorderly, with the largest velocity gradient near the air-water interface. The tangential velocity distribution of the rotational flow can be regarded as the combined vortex distribution, especially obvious in the vortex chamber and the gradient section. [ABSTRACT FROM AUTHOR]

目的 对比观察髌上与髌下入路髓内钉置入术在胫骨干远段骨折复位中的应用效果.方法 髓内钉置 入术治疗的胫骨干远段骨折患者80例, 其中40例采用经髌上入路髓内钉置入术治疗（髌上组）, 40例采用传统经髌 下入路髓内钉置入术治疗（髌下组）.比较两组术后骨折端成角及力线不良发生率.结果 两组术后骨折端成角均 得到有效纠正, 术前术后骨折端成角比较, P<0. 05.髌上组术后冠状面及矢状面骨折端成角分别为2. 25° ± 1. 43°、 2. 45° ± 1. 22°, 髌下组术后骨折端冠状面及矢状面成角分别为2. 25° ± 2. 08°、2. 89° ± 2. 31°, 两组比较, P均>0. 05. 髌上组、髌下组术后下肢总体力线不良发生率分别为5%、22. 5%, 两组比较差异有统计学意义(P =0. 023).髌上组 与髌下组术后矢状面力线不良发生率分别为 5%、20%, 两组比较, P<0. 05；术后冠状面力线不良发生率分别为 7. 5%、2. 5%, 两组比较, P>0. 05.结论 与髌下入路髓内钉置入术比较, 髌上入路髓内钉置入术对胫骨干远段骨折 复位效果好, 术后下肢力线不良发生率低. [ABSTRACT FROM AUTHOR]

In view of the complicated distribution of fluctuating pressure on the stilling basin slab with sudden enlargement and bottom drop, based on FLOW-3 D software, large eddy model and tru VOF method were used to simulate the time-averaged pressure, root-mean-square of fluctuating pressure and power spectral density. The comparison between the simulation results and the experimental results shows that the large eddy model can simulate the water flow fluctuating pressure in stilling basin with sudden lateral enlargement and bottom drop suitably. The maximum value of root-mean-square fluctuating pressure appears in the vicinity of the front of the stilling basin and the extension line of the venting side wall. The distribution of fluctuating pressure at the bottom of underflow swirling zone and the wall-attached jet zone are affected by the vortex and fluctuating velocity, respectively, and the impact zone is caused by both. [ABSTRACT FROM AUTHOR]