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71.
沥青混合料水稳定性评价方法研究 总被引:2,自引:0,他引:2
分析比较了4种评价沥青混合料水稳定性评价方法即浸水马歇尔试验、冻融劈裂试验、沥青路面分析仪浸水车辙试验和朱丽叶试验的优缺点和试验条件.从试件性能的稳定性、试验模拟的环境条件、评价指标的有效性而言,沥青路面分析仪浸水车辙试验最好,朱丽叶试验次之,冻融劈裂试验第三,而浸水马歇尔试验最差.但从试验方法的可操作性而言,沥青路面分析仪浸水车辙试验最差.通过不同评价指标的相关性分析,研究不同试验方法内在区别和联系,从而为实际工程运用提供一些参考. 相似文献
72.
Ages of the stratigraphic boundary MIS1/2 and MIS3/4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3/4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3/4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3: 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model. 相似文献
73.
Ages of the stratigraphic boundary MIS1/2 and MIS3/4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3/4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3/4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3: 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model. 相似文献
74.
本文以LabVIEW程序语言为核心,介绍了远程温度采集系统的原理、软硬件组成和实现过程,并以化学反应中的温度测量为例,通过串口完成了温度数据的快速采集。此类测控系统价格低廉且构建快速,可以方便的移植到其他众多领域。 相似文献
75.
76.
温度作用是超长结构设计中需要解决的主要问题,本文通过对某工程弧形超长的混凝土结构与钢结构的温度作用进行了分析,与矩形超长结构进行了对比,验证了弧形体型有利于释放温度应力。同时提出了有反弯点的连续弧形结构的等效温度区段长度的计算方法,以供类似工程参考。 相似文献
77.
In the process of ferromagnetic thermoseeds mediated magnetic induction hyperthermia, the tempera- ture distribution in the tumor region is a key factor to determine the therapy effect. During the preoperative treatment planning, discrepancies of the treatment parameters may lead to the temperature distribution uncertainty within the target area. Inaccurate prediction of temperature distribution may induce the treatment failure; therefore, it would be significant to investigate the uncertainty of tissue temperature prediction caused by the disturbance of calculation parameters. In this paper, 3D temperature field and necrosis zone of tissues in ferromagnetic thermoseeds hyperthermia are simulated by the finite volume algorithm, and effects of parameter uncertainties on the temperature distribution are revealed. Results show that selecting appropriate magnetic field parameters for treatment is a priority to guarantee therapeutic effect. Thermoseed properties and blood perfusion rate are the obvious disturbing terms for temperature distribution, while the metabolic heat of bio-tissues can often be ignored within limits. Our investigation is of importance for guiding reasonable and optimal preoperative treatment planning. 相似文献
78.
利用铁磁性分子场理论的基础上,通过引入热无序能、冷无序能、与自发磁化相关的有序能之间的竞争机制下,引入了有效分子场系数.利用考虑与温度相关的有效分子场系数λ(T)的分子场理论研究了αFe的磁化特征,得到了与实验相符的结论,解释了铁磁性物质的约化自发磁化强度与温度的关系,解释了C/χ-T曲线在磁相变温度附近向上弯曲的原因,解释了顺磁居里温度θP大于铁磁居里温度TC的实验结果,解释了铁磁性物质中的有序-无序竞争与宏观磁性的关系. 相似文献
79.
80.
研究了滑石粉和炭黑对软质聚氯乙烯的硬度及其温度依赖性和力学性能的影响,并将它们同ABS和MBS进行了比较,高度填充和适当的滑石粉/炭黑组合能提高软质PVC的硬度和降低硬度对温度的依赖性,并使材料保持较好的力学性能和低温柔性。 相似文献