基于区域统筹视角下的城镇型风景名胜边界划定方法初探

边界划定是风景名胜区保护规划的关键环节,合理划定城镇型风景名胜区边界尤为重要。本文摆脱传统边界划定仅从风景区保护出发的单一视角,提出基于区域统筹视角下的城镇型风景区边界划定新方法,即力场分析法,并重点探讨了风景名胜区与城镇建设区相交区域边界的划定。     

Effect of rare earth oxides on the morphology of carbides in hardfacing metal of high chromium cast iron

The flux cored wires with different amounts of rare earth (RE) oxides additions for hardfacing (harden-face-welding) the workpieces of high chromium cast iron were studied in this work.The morphology of carbides in hardfacing metal was observed,and the type of the carbides was determined by optical microscopy,scanning electron microscopy (SEM),energy dispersive spectrometer (EDS) and X-ray diffraction (XRD).Based on the data of effect of RE on carbides morphology,the refined reason for carbide by RE oxide was discussed with the misfit theory.The results showed that,the microstructure of hardfacing metal was composed of martensite,residual austenite and M7C3 carbides.With the increasing amount of RE oxide additions,the volume fraction and roundness of the carbides were increased,however,the area and perimeter of carbides were decreased.It indicated that carbides in hardfacing metal could be refined and spheroidized by adding RE oxides in flux cored wires.     

Cu-P-Cr-Ni-Mo耐候钢高温变形奥氏体的动态再结晶

用Gleeble-3500热模拟试验机研究了Cu-P-Cr-Ni-Mo耐候钢(%:0.10C、0.075P、0.65Cr、0.22Ni、0.43Mo、0.28Cu)在应变速率0.01～1 s~(-1)、温度850～1150℃时的动态再结晶行为,得出该钢奥氏体区的真应力-真应变曲线和动态再结晶图,分析了变形参数对峰值应力的影响和不同热变形时耐候钢的动态再结晶体积分数与真应变的关系,建立了该钢的奥氏体热变形方程、动态再结晶临界条件回归方程和奥氏体动态再结晶体积分数数学模型。结果表明,随变形温度升高,峰值应力下降;随变形速率增大,峰值应力升高;随Z参数增大即变形温度降低,应变速率增加,发生再结晶的临界应变ε_c和发生完全再结晶的应变ε_s均呈线性增加。     

X52管线钢热变形行为的研究

用Gleeble-3500热模拟试验机对X52(L360)管线钢(%:0.08C、0.20Si、0.93Mn、0.024Als、0.02Nb、0.02Ti)在950～1200℃、应变速率0.01～10 s~(-1)时进行50%热压缩变形试验,得出真应力-应变曲线。通过回归分析,确定X52钢热变形激活能和热变形方程,得出应变速率、温度和Z参数对热形变峰值应力的影响。结果表明,变形温度降低,峰值应力增加并向应变增大方向移动,随变形速率增加,峰值应力增大并且也向应变增大方向移动;X52钢热变形激活能为232 kJ/mol;随Z参数增加,热变形峰值应力增加。     

胶基电敏复合材料传感技术实测加筋土墙的变形

针对目前土工合成材料变形测试中存在的问题，研发了胶基电敏复合材料传感技术。通过在橡胶绝缘基体中充填导电填料获得具有导电、力敏、柔韧、高弹等特性的复合材料，基于此种复合材料制作了具有测试低模量、柔性基材及大变形等特点的土工筋带变形测试传感器。利用该传感技术对某露天矿选煤厂槽仓基坑工程中的加筋土挡墙进行了现场实测。结果表明，筋带拉力与埋深成正比关系；单条筋带中，受力最大点位于沿筋带长度1/2~2/3处，筋带受力处于安全状态。新型传感技术为加筋材料变形测试提供了新的方法与手段。     

环氧树脂增韧改性的研究进展

介绍了环氧树脂韧性差、脆性大的缺点和环氧树脂增韧改性的主要途径,概述了近年来利用橡胶弹性体、热塑性树脂、液晶聚合物、无机纳米填料、有机硅、超支化聚合物、柔性固化剂以及互穿网络等方法来增韧环氧树脂的原理,分析了目前各种增韧改性技术存在的问题,指出了环氧树脂增韧技术的最新研究进展,并对将来的发展趋势进行了展望。     

Effects of contents of Nb and C on hot deformation behaviors of high Nb X80 pipeline steels

The behavior of the flow deformation and the effects of contents of Nb and C on deformation behaviors of high Nb X80 pipeline steels during hot compression deformation were studied by thermal simulation test. The content of solid solution Nb was quantificationally studied during the reheating and hot deformation process, and the effects of change of solid solution Nb in steels on hot deformation behaviors were discussed. The results show that the contents of Nb and C have great effects on the flow stress behaviors of high Nb X80 pipeline steels. When the C content in steels is constant, the recrystallization activation energy increases from 387 to 481 kJ/mol with increasing the Nb from 0.082% to 0.13% (mass fraction). However, the effect of Nb is correlative to the C content, i.e. w(Nb)/w(C). When w(Nb)/w(C) decreases from 3.61 to 2.18, the recrystallization activation energy decreases from 481 to 434 kJ/mol.     

高频电阻焊管用低强度钢的热处理工艺

采用Gleeble-3500型热模拟试验机研究了加热速度、加热温度以及冷却速度对高频焊管用钢的组织和性能的影响规律。结果表明:加热速度对奥氏体相变点有显著影响,随加热速度的提高,相变点呈线性增加。在850～1000℃范围内,当加热温度达到925～950℃时,强度达到最低值。随加热温度进一步升高,强度增加。随冷却速度的降低,钢的强度显著下降,组织粗化,且出现带状组织。     

我国矿井热害现状及井下地热利用探讨

阐述了热害的基本概念、热害等级的划分以及与之相关的安全规定，总结了我国几大矿区的热害现状，并对井下地热的利用提出了两个方案，归纳了井下地热利用尚待解决的问题，以解决矿井热害问题，促进井下地热的利用研究。