山前平原地下水侧向补给潜力空间变异模拟

SWAT模型利用分辨率较高的DEM数据,可以估算山前地下水侧向补给的空间变异,并可以计算不同降水年型下补给量的差别。模拟需要对研究区进行填洼、流向确定、汇流和河网水系的提取四步运算,并对河道临界支撑面积的取值进行分析。分别模拟了平水年和丰水年两种降雨年型下研究区13个出水口的地下水侧向补给潜力。在研究区,由于地形的变化,导致山与平原交接断面上出水口的集水面积变异非常大,因此山前平原所接受的地下水侧向补给量的空间变异也非常大。不同的降雨年型下,降雨量转化为地下水侧向补给量的比例也不同。平水年的转化比例较小,丰水年的转化比例较大。应用SWAT模型时,与ArcView的拓展模块有机结合,可以更方便提取完整的大流域,划分出合理的子流域。     

矿山抗采动农村楼房的试验研究

本文通过两栋不同加固方案的二层农村楼房抗采动现场试验结果的分析,对不同加固措施的作用机理、效果及其设置条件进行了研究探讨,并提出,在农村采动区兴建抗采动变形楼房,是解放村庄下压煤、节约耕地和降低加固费用的途径。     

宁夏引黄灌区渠道防渗衬砌技术研究

对宁夏引黄灌区渠道防渗衬砌的形式、防渗衬砌效果、渠道防渗衬砌工程的技术指标、冻害特征、防治措施进行了综合应用分析与研究,提出了不同级别渠道适宜的衬砌形式、推广渠道防渗衬砌的技术要求,供灌区节水工程改造、渠道衬砌工程参考。     

Dynamic response of a Mindlin elastic rectangular plate under a distributed moving mass

The elastodynamic response of a rectangular Mindlin plate subjected to a distributed moving mass is investigated. The set of governing characteristic partial differential equations that include the effects of shear deformation and rotary inertia is expressed in its dimensionless form. A finite difference algorithm is employed to transform the differential equations into a set of linear algebraic equations. Simply supported edge conditions were used as an illustrative example. The analysis is also valid for other edge conditions. It is found that the maximum shearing forces, bending and twisting moments occur almost the same time. Also, the values of the maximum deflections are higher for Mindlin plates than for non-Mindlin plates.     

中心孔锥面面积对轴类零件加工精度的影响

中心孔的研磨质量直接影响着轴类零件的加工精度,特别是大型轴类零件。作者分析了标准中心孔存在的缺点,采用减小中心孔锥面面积的措施来保证工件加工精度。实践证明,这种方法在成批生产中使用效果良好。     

运用古地磁方法测定油气成藏时限——以桩海地区下古生界潜山油气藏为例

运用古地磁厘定油气成藏时限是一种新的岩石地球物理方法。对采于桩海地区下古生界的6块岩心样品进行了系统交变退磁实验,分离出2个正极性分量:A分量(10～30mT)是现代地磁场的重磁化;B分量(30～60mT)是新生代烃类流体与下古生界碳酸岩储层相互作用的结果,对应的古地磁极位置为288.95oE、73.58oN。参考华北地块新生代古地磁极移曲线,推定本区下古生界古潜山油气藏的成藏时限为晚第三纪中新世早期(14～18Ma)。这种新方法在中、新生代油气藏成藏时限研究中具有一定的应用前景。     

山岭重丘区公路工程技术方案的选择

对高填方与高架桥和深路堑与隧道两个典型技术方案，进行了费用分析，寻找方案选择的工程临界值，以提高工程设计的经济性和合理性。重点提出了工程可替代方案间填挖高判断值，对工程可行性研究阶段山岭重丘区的公路工程技术方案的选择有一定参考价值。     

Analysis of hazard area associated with hydrogen gas transmission pipelines

Hydrogen is considered to be the most important future energy carrier in many applications reducing significantly greenhouse gas emissions, but the safety issues associated with hydrogen applications need to be investigated and fully understood to be applicable as the carrier. Generally, the locations of hydrogen production and consumption are different. Hydrogen must be transported from the point of production to the point of use. Pipeline delivery is cheaper than all other methods for large quantities of hydrogen. The rupture of a hydrogen pipeline can lead to outcomes that can pose a significant threat to people and property in the immediate vicinity of the failure point. In this work, a simplified equation of hazard analysis is proposed for the pipeline transporting hydrogen, which relates the diameter, the operating pressure and the length of the pipeline to the size of the affected area in the event of a failure of the pipeline. The dominant hazards are thermal radiation from sustained fire and shock pressure from gas cloud explosion. For a transmission pipeline of hydrogen gas, the hazard area from the fire is slightly larger than by the other event. The hazard area is directly proportional to the operating pressure raised to the power one-half, and to the pipeline diameter. This simplified equation to estimate the hazard area will be a useful tool for safety management of hydrogen gas transmission pipelines.     

塔中西北部奥陶系碳酸盐岩埋藏溶蚀作用

对塔中西北部奥陶系碳酸盐岩埋藏溶蚀发育的地质背景、充填矿物(岩石)学-地球化学特征进行了研究,埋藏溶蚀作用在碳酸盐岩储层发育中有重要作用。塔中西北部多期次构造活动和中-晚二叠世为主的岩浆—热液活动是埋藏溶蚀产生的基本条件;深埋或热液作用是以黄铁矿、绿泥石、石英、铁方解石、萤石等标型矿物和具有能发出明亮桔黄色光的富锰贫铁方解石胶结物、生长环带、铁白云石溶蚀等特征。方解石充填物中富含铁、锰、镁、锶等元素,δ¹⁸O_PDB平均值为-6.6‰ ,δ¹³C_PDB平均值为-2.0‰;流体包裹体均一温度为115~130℃和170~210℃,盐度为5%~7%/、8%~9%和12%~13% ,反映了埋藏成岩作用中有深部流体或循环流体参与。     

黄河流域多沙粗沙区植被覆盖变化与减水减沙效益分析

通过遥感手段和数字流域模型,研究了黄河流域多沙粗沙区近10来年的植被覆盖变化及其减水减沙效益。研究表明,多沙粗沙区90年代末期与80年代末期相比,植被覆盖度增加区域大约占50%,植被覆盖度没变化区域约占48%。植被覆盖度的变化导致了流域水沙条件的变化,90年代末期植被覆盖条件下,植被措施的减水减沙百分比不高;不同的降雨过程,植被措施的减水减沙效益有一定的差别;从不同降雨过程多年平均看,近10来年植被措施年均减水2.63亿m3,减沙1.13亿t,减水减沙比为2.75,即减1亿t沙的同时减水2.75亿m3,减水百分比为7.61,减沙百分比为10.56,减沙效益大于减水效益。