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钢管桩防腐蚀性能检测评估技术及工程应用研究

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北方交通 2025年第2期 1-4页

作者：童浩林峰江苏省高速公路经营管理中心南京市210003

依托崇启大桥,开展在役近海桥梁钢管桩防腐蚀性能检测,通过钢管桩和牺牲阳极外观检测、钢管桩电位分析、阳极电化学性能分析及消耗量检测,评估大桥钢管桩的使用现状及防腐蚀效果。结果表明:钢管桩表观质量良好,牺牲阳极外表面坑洼较多,... 详细信息

依托崇启大桥,开展在役近海桥梁钢管桩防腐蚀性能检测,通过钢管桩和牺牲阳极外观检测、钢管桩电位分析、阳极电化学性能分析及消耗量检测,评估大桥钢管桩的使用现状及防腐蚀效果。结果表明:钢管桩表观质量良好,牺牲阳极外表面坑洼较多,且主桥段阳极消耗相对较快;钢管桩电位均在设计阴极保护电位范围内;崇启大桥钢管桩保护良好,牺牲阳极满足设计寿命要求。

关键词：钢管桩牺牲阳极阳极消耗量剩余使用寿命

An accreting low magnetic field magnetar for the ultraluminous X-ray source in M82

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Research in Astronomy and Astrophysics 2015年第4期15卷 517-524页

作者： hao tong Xinjiang Astronomical Observatory Chinese Academy of Sciences

One ultraluminous X-ray source in M82 has recently been identified as an accreting neutron star （named NuSTAR J095551＋6940.8）. It has a super-Eddington luminosity and is spinning up. An aged magnetar is more likely to be a low magnetic field magnetar. An accreting low magnetic field magnetar may explain both the super- Eddington luminosity and the rotational behavior of this source. Considering the effect of beaming, the spin-up rate is understandable using the traditional form of accretion torque. The transient nature and spectral properties of M82 X-2 are discussed. The theoretical range of periods for accreting magnetars is provided. Three observational appearances of accreting magnetars are summarized.

关键词： accretion -- pulsars: individual (NuSTAR J095551+6940.8) -- stars:magnetars -- stars: neutron

A note on the puzzling spindown behavior of the Galactic center magnetar SGR J1745-2900

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Research in Astronomy and Astrophysics 2015年第9期15卷 1467-1474页

作者： hao tong Xinjiang Astronomical Observatory Chinese Academy of Sciences

SGR J1745-2900 is a magnetar near the Galactic center. X-ray observations of this source found a decreasing X-ray luminosity accompanied by an enhanced spindown rate. This negative correlation between X-ray luminosity and spindown rate is hard to understand. The wind braking model of magnetars is employed to explain this puzzling spindown behavior. During the release of magnetic energy of magnetars, a system of particles may be generated. Some of these particles remain trapped in the magnetosphere and may contribute to the X-ray luminosity. The rest of the particles can flow out and take away the rotational energy of the central neutron star. A smaller polar cap angle will cause the decrease of X-ray luminosity and enhanced spindown rate of SGR J1745-2900. This magnetar is shortly expected to have a maximum spindown rate.

关键词： pulsars: individual (SGR J1745-2900) -- stars: magnetar -- stars: neu-tron -- stars: winds

Understanding the circular polarization of fast radio bursts observed by the Five-hundred-meter Aperture Spherical Radio Telescope

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Science China(Physics,Mechanics & Astronomy) 2022年第10期65卷 155-156页

作者： hao tong School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China

China's Five-hundred-meter Aperture Spherical Radio Telescope(FAST)is the world's largest single-disk radio *** of its high sensitivity,it can reveal the most intriguing properties of pulsars and fast radio bursts(FRBs).

关键词： bursts telescope observed

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On the possible wind nebula of magnetar Swift J1834.9-0846:a magnetism-powered synchrotron nebula

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Research in Astronomy and Astrophysics 2016年第9期16卷 91-94页

作者： hao tong Xinjiang Astronomical Observatory Chinese Academy of Sciences

Recently, the magnetar Swift J1834.9-0846 has been reported to have a possible wind nebula. It is shown that both the magnetar and its wind nebula are understandable in the wind braking scenario. The magnetar＇s rotational energy loss rate is not enough to power the particle luminosity. The required particle luminosity should be about 10^36 erg s^- 1 to 10^38 erg s^-1. It is obtained in three different approaches： considering wind braking of Swift J1834.9-0846; the spectral and spatial observations of the wind nebula; and an empirical upper bound on wind nebula X-ray luminosity. The nebula magnetic field is about 10-4 G. The possible wind nebula of Swift J1834.9-0846 should be a magnetar wind nebula. It is powered by the magnetic energy released from the magnetar.

关键词： pulsars individual (Swift J1834.9-0846) -- stars magnetars -- stars neutron -- winds and outflows

Circular Polarization of Fast Radio Bursts in the Curvature Radiation Scenario

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Research in Astronomy and Astrophysics 2022年第7期22卷 206-213页

作者： hao tong Hong-Guang Wang School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China

The curvature radiation is applied to the explanation of the circular polarization of fast radio bursts(FRBs).Significant circular polarization is reported in both apparently non-repeating and repeating *** radiation can produce significant circular polarization at the wing of the radiation *** the curvature radiation scenario,in order to see significant circular polarization in FRBs,(1) more energetic bursts,(2) bursts with electrons having higher Lorentz factor,and(3) a slowly rotating neutron star at the center are *** rotational period of the central neutron star may explain why some FRBs have high circular polarization,while others do *** possible difference in refractive index for the parallel and perpendicular components of electric field,the position angle may change rapidly over the narrow pulse window of the radiation *** position angle swing in FRBs may also be explained by this non-geometric origin,besides that of the rotating vector model.

关键词： stars:magnetars (stars:)pulsars:general polarization

Experimental Research on Effects of Process Parameters on Servo Scanning 3D Micro Electrical Discharge Machining

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 114-121页

作者： tong hao LI Yong HU Manhong State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

Servo scanning 3D micro electrical discharge machining (3D SSMEDM) is a novel and effective method in fabricating complex 3D micro structures with high aspect ratio on conducting materials. In 3D SSMEDM process, the axial wear of tool electrode can be compensated automatically by servo-keeping discharge gap, instead of the traditional methods that depend on experiential models or intermittent compensation. However, the effects of process parameters on 3D SSMEDM have not been reported up until now. In this study, the emphasis is laid on the effects of pulse duration, peak current, machining polarity, track style, track overlap, and scanning velocity on the 3D SSMEDM performances of machining efficiency, processing status, and surface accuracy. A series of experiments were carried out by machining a micro-rectangle cavity (900 μm×600 μm) on doped silicon. The experimental results were obtained as follows. Peak current plays a main role in machining efficiency and surface accuracy. Pulse duration affects obviously the stability of discharge state. The material removal rate of cathode processing is about 3/5 of that of anode processing. Compared with direction-parallel path, contour-parallel path is better in counteracting the lateral wear of tool electrode end. Scanning velocity should be selected moderately to avoid electric arc and short. Track overlap should be slightly less than the radius of tool electrode. In addition, a typical 3D micro structure of eye shape was machined based on the optimized process parameters. These results are beneficial to improve machining stability, accuracy, and efficiency in 3D SSMEDM.

关键词： micro electrical discharge machining(micro EDM) servo scanning machining 3D micro-structure process parameter

The timing behavior of magnetar Swift J1822.3—1606: timing noise or a decreasing period derivative?

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Research in Astronomy and Astrophysics 2013年第10期13卷 1207-1212页

作者： hao tong Ren-Xin Xu Xinjiang Astronomical Observatory Chinese Academy of Sciences KIAA and School of Physics Peking University

The different timing results of the magnetar Swift J1822.3—1606 are analyzed and understood *** is noted that different timing solutions are caused not only by timing noise,but also because the period derivative is decreasing after the *** the decreasing period derivative and the large timing noise may originate from wind braking associated with the *** timing of Swift J1822.3—1606 will help clarify whether or not its period derivative is decreasing with time.

关键词： pulsars:individual(Swift J1822.3—1606) stars:magnetar stars:neutron

融合数据驱动稳定性分析的快速路车队追尾冲突预测

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东南大学学报(自然科学版) 2025年第1期55卷 239-245页

作者：王长帅任卫林徐铖铖佟昊邵永成彭畅东南大学交通学院南京211189

为探究车队弦稳定性指标与交通状态变量对车队尾车追尾冲突的影响,提取了1 085条包含连续5辆车的轨迹数据,以最小碰撞时间为评价指标,将尾车的跟驰状态划分为冲突与非冲突2种。利用数据驱动的弦稳定性分析方法,计算车队弦稳定性指标值,... 详细信息

为探究车队弦稳定性指标与交通状态变量对车队尾车追尾冲突的影响,提取了1 085条包含连续5辆车的轨迹数据,以最小碰撞时间为评价指标,将尾车的跟驰状态划分为冲突与非冲突2种。利用数据驱动的弦稳定性分析方法,计算车队弦稳定性指标值,构建了仅包含交通状态变量、仅包含弦稳定性指标、融合交通状态变量与弦稳定性指标的3种追尾冲突预测模型,解析不同因素对尾车追尾冲突的影响。研究结果表明,融合交通状态变量与弦稳定性指标的预测模型表现最好,其准确率、精确率和召回率分别为95.90%、93.60%和89.80%。车队弦稳定性指标值越大,尾车发生追尾冲突的概率越高。尾车加速度的标准差、前车的最小车头间距、尾车车头间距的标准差和车头时距的标准差等也是影响追尾冲突的重要因素。

关键词：交通安全追尾冲突数据驱动稳定性分析轨迹数据

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