采用M80弹(7.62 mm×51 mm NATO)分别对常温和高温(55℃)下的防弹插板进行实弹射击试验,以研究高温环境对防弹插板抗弹性能的影响。通过分析试验时防弹插板弹击瞬间凹陷值,同时结合聚氨酯树脂的剥离强度、超高分子量聚乙烯纤维层压...采用M80弹(7.62 mm×51 mm NATO)分别对常温和高温(55℃)下的防弹插板进行实弹射击试验,以研究高温环境对防弹插板抗弹性能的影响。通过分析试验时防弹插板弹击瞬间凹陷值,同时结合聚氨酯树脂的剥离强度、超高分子量聚乙烯纤维层压板剥离强度和弯曲强度的测试结果对高温下抗弹性能变化原因进行了研究。结果表明:高温下防弹插板抗弹性能明显下降,相对于常温下每发弹的弹击瞬间凹陷值增加了2~5 mm。其主要原因是超高分子量聚乙烯纤维层压板在高温下抵抗变形的能力发生明显下降,从而导致防弹插板的弹击瞬间凹陷值增大。展开更多
The full-space transient electromagnetic response of water-filled goaves in coal mines were numerically modeled. Traditional numerical modeling methods cannot be used to simulate the underground full-space transient e...The full-space transient electromagnetic response of water-filled goaves in coal mines were numerically modeled. Traditional numerical modeling methods cannot be used to simulate the underground full-space transient electromagnetic field. We used multiple transmitting loops instead of the traditional single transmitting loop to load the transmitting loop into Cartesian grids. We improved the method for calculating the z-component of the magnetic field based on the characteristics of full space. Then, we established the full- space 3D geoelectrical model using geological data for coalmines. In addition, the transient electromagnetic responses of water-filled goaves of variable shape at different locations were simulated by using the finite-difference time-domain （FDTD） method. Moreover, we evaluated the apparent resistivity results. The numerical modeling results suggested that the resistivity differences between the coal seam and its roof and floor greatly affect the distribution of apparent resistivity, resulting in nearly circular contours with the roadway head at the center. The actual distribution of apparent resistivity for different geoelectrical models of water in goaves was consistent with the models. However, when the goal water was located in one side, a false low-resistivity anomaly would appear on the other side owing to the full-space effect but the response was much weaker. Finally, the modeling results were subsequently confirmed by drilling, suggesting that the proposed method was effective.展开更多
Isoplethic VLE data for the systems benzene-hexane at 9 different compositions in the temperature range from 298 K to 331K, chloroform-benzene at 11 different compositions in the temperature range from 308 K to 350 K ...Isoplethic VLE data for the systems benzene-hexane at 9 different compositions in the temperature range from 298 K to 331K, chloroform-benzene at 11 different compositions in the temperature range from 308 K to 350 K and chloroform-hexane at 9 different compositions in the temperature range from 311 K to 337 K were determined by using an inclined ebulliometer with a pump-like stirrer. Isothermal and isobaric VLE were calculated from the isoplethic results with a extended UNIQUAC equation and these data agree well with the literature data.展开更多
文摘采用M80弹(7.62 mm×51 mm NATO)分别对常温和高温(55℃)下的防弹插板进行实弹射击试验,以研究高温环境对防弹插板抗弹性能的影响。通过分析试验时防弹插板弹击瞬间凹陷值,同时结合聚氨酯树脂的剥离强度、超高分子量聚乙烯纤维层压板剥离强度和弯曲强度的测试结果对高温下抗弹性能变化原因进行了研究。结果表明:高温下防弹插板抗弹性能明显下降,相对于常温下每发弹的弹击瞬间凹陷值增加了2~5 mm。其主要原因是超高分子量聚乙烯纤维层压板在高温下抵抗变形的能力发生明显下降,从而导致防弹插板的弹击瞬间凹陷值增大。
基金supported by the National Key Scientific Instrument and Equipment Development Project(No.2011YQ03013307)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education InstitutionsKey Laboratory of Coal Resources Exploration and Comprehensive Utilization,Ministry of Land and Resources
文摘The full-space transient electromagnetic response of water-filled goaves in coal mines were numerically modeled. Traditional numerical modeling methods cannot be used to simulate the underground full-space transient electromagnetic field. We used multiple transmitting loops instead of the traditional single transmitting loop to load the transmitting loop into Cartesian grids. We improved the method for calculating the z-component of the magnetic field based on the characteristics of full space. Then, we established the full- space 3D geoelectrical model using geological data for coalmines. In addition, the transient electromagnetic responses of water-filled goaves of variable shape at different locations were simulated by using the finite-difference time-domain （FDTD） method. Moreover, we evaluated the apparent resistivity results. The numerical modeling results suggested that the resistivity differences between the coal seam and its roof and floor greatly affect the distribution of apparent resistivity, resulting in nearly circular contours with the roadway head at the center. The actual distribution of apparent resistivity for different geoelectrical models of water in goaves was consistent with the models. However, when the goal water was located in one side, a false low-resistivity anomaly would appear on the other side owing to the full-space effect but the response was much weaker. Finally, the modeling results were subsequently confirmed by drilling, suggesting that the proposed method was effective.
基金Supported by Zhejiang Provincial Natural Science Foundation of China.
文摘Isoplethic VLE data for the systems benzene-hexane at 9 different compositions in the temperature range from 298 K to 331K, chloroform-benzene at 11 different compositions in the temperature range from 308 K to 350 K and chloroform-hexane at 9 different compositions in the temperature range from 311 K to 337 K were determined by using an inclined ebulliometer with a pump-like stirrer. Isothermal and isobaric VLE were calculated from the isoplethic results with a extended UNIQUAC equation and these data agree well with the literature data.
