Compact and tunable mid-infrared source based on a 2 μm dual-wavelength KTiOPO₄ intracavity optical parametric oscillator     

耿优福  谭晓玲  李学金  姚建铨 《海洋学报(英文版)》2010,29(11)

Using a double resonant KTiOPO₄ (KTP) intracavity optical parametric oscillator operating at degenerated point of 2 μm, we demonstrate a unique mid-infrared source based on difference frequency generation in GaSe crystal. The output tuning range is 8.42-19.52 μm, and a peak power of 834 W for type-I phase matching scheme and 730 W for type-II phase matching scheme are achieved. Experimental results show that this oscillator is a good alternative to the generator of a compact and tabletop mid-infrared radiation with a widely tunable range.  相似文献   

地层压力和大直径套管抗挤压力计算   总被引：2，自引：0，他引：2  

张平占  叶礼明 《煤田地质与勘探》1995,23(1):62-66

介绍了上覆地层压力和粘土吸水膨胀对套管挤压以及大直径管受外挤力失稳破坏的计算方法。解决了现场遇到的实际问题。  相似文献   

声幅—变密度测井原理及测井解释方法     

李新胜  周俊乐 《陕西地质》2007,25(2):54-59

对利用声幅—变密度测井判断固井质量的测井原理和工作方式及资料的解释处理进行了介绍,并对固井中出现的各种可能曲线反映进行了详尽的分析,阐述了资料解释中不确定因素。  相似文献   

辽东湾丛式钻井陀螺侧钻及导向钻井防碰技术     

姜伟 《四川地质学报》1992,(4)

本文介绍渤海辽东湾实验区AI平台丛式定向井最后钻完的3口侧钻绕障井。在有邻井和本井套管磁干扰情况下,特别是与邻井间距最小仅为0.6m,采用陀螺定向侧钻以及导向钻井技术相结合,安全顺利的钻完了这3口井。总结和介绍了侧钻、防碰的工艺特声,以及安全措施。研究和分析了使用陀螺定向侧钻,钻速与造斜率,井眼轨迹合理控制等问题。  相似文献   

Influence of long‐period filter cut‐off on elastic spectral displacements     

Sinan Akkar  Julian J. Bommer 《地震工程与结构动力学》2006,35(9):1145-1165

The effect of the long‐period filter cut‐off, T_c, on elastic spectral displacements is investigated using a strong ground‐motion database from Europe and the Middle East. The relation between the filter and oscillator responses is considered to observe the influence of T_c for both analogue and digital records, and the variations with site classification, magnitude, filter order and viscous damping. Robust statistics are derived using the re‐processed European data to generalize the effects of the long‐period filter cut‐off on maximum oscillator deformation demands as a function of these seismological and structural features. Statistics with a 95% confidence interval are derived to suggest usable period ranges for spectral displacement computations as a function of T_c. The results indicate that the maximum period at which spectral displacements can be confidently calculated depend strongly on the site class, magnitude and filter order. The period range where reliable long‐period information can be extracted from digital accelerograms is twice that of analogue records. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

Yielding oscillator subjected to simple pulse waveforms: numerical analysis & closed‐form solutions     

George Mylonakis  Elia Voyagaki 《地震工程与结构动力学》2006,35(15):1949-1974

Numerical and analytical solutions are presented for the elastic and inelastic response of single‐degree‐of‐freedom yielding oscillators to idealized ground acceleration pulses. These motions are typical of near‐fault earthquake recordings generated by forward rupture directivity and may inflict damage in the absence of substantial structural strength and ductility capacity. Four basic pulse waveforms are examined: (1) triangular; (2) sinusoidal; (3) exponential; and (4) rectangular. In the first part of the article, a numerical study is presented of the effect of oscillator period, strength, damping, post‐yielding stiffness and number of excitation cycles, on inelastic response. Results are presented in the form of dimensionless graphs and regression formulas that elucidate the salient features of the problem. It is shown that conventional R–µ relations may significantly underestimate ductility demand imposed by near‐fault motions. The second part of the article concentrates on elastic‐perfectly plastic oscillators. Closed‐form solutions are derived for post‐yielding response and associated ductility demand. It is shown that all three ground motion histories (i.e. acceleration, velocity, and displacement) control oscillator response—contrary to the widespread view that ground velocity alone is of leading importance. The derived solutions provide insight on the physics of inelastic response, which is often obscured by the complexity of numerical algorithms and actual earthquake motions. The model is evaluated against numerical results from near‐field recordings. A case study is presented. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

嫩江组二段底部标志层岩石矿物学特征与成片套损因素新认识   总被引：1，自引：0，他引：1  

刘合卓胜广  高合明刘建东吴恩成  金岩松 《地质论评》2006,52(4):532-538

大庆油田嫩江组二段底部与嫩江组一段顶部成片套损严重，从前一直认为泥岩吸水膨胀、蠕变是导致成片套损的主要因素。成片套损位置研究发现，嫩江组二段底部与嫩江组一段顶部成片套损实际集中于嫩江组二段底部标志层内，而嫩江组二段底部标志层岩石矿物学特征综合研究结果表明，其不含遇水膨胀的蒙脱石，且粘土矿物含量也低于其上下相邻岩石，表明其遇水膨胀与蠕变较弱，岩石遇水膨胀与蠕变不会构成成片套损的主要原因。嫩江组二段底部标志层岩石岩心观察描述、镜下鉴定、矿物成分综合测试和岩石强度性质研究发现，嫩江组二段底部标志层泥岩为富含长英质的质地坚硬岩石，含粘土矿物较少，不含蒙脱石，岩石吸水能力差、膨胀与蠕变能力弱；标志层中存在多个化石富集带，化石沿岩石层理分布形成沿层理方向的区域性力学薄弱面；沿化石层层理的抗张强度与抗剪强度远低于其他层位和垂直于层理方向的强度性质。因此，一旦注入水进入嫩江组二段底部标志层，富含化石的岩石沿岩石层理优先发生破坏，并迅速扩展，形成成片套损现象。  相似文献   

潜孔锤跟管钻进技术在小浪底水利观测孔工程的应用     

郑玉辉 《探矿工程》2007,34(8):4-5,12

在黄河小浪底水利枢纽观测孔工程中,采用气动潜孔锤跟管钻进结合双动力头钻机成功地解决了普通气动潜孔锤及常规钻进工艺在厚度达50 m渣石层成孔难的问题。  相似文献   

偏心跟管成孔技术在破碎地层边坡锚固中的应用          下载免费PDF全文

李斌 《探矿工程》2007,34(11):49-50

介绍了偏心跟管成孔施工技术在破碎地层边坡的预应力锚固处理中的应用,该技术的成功运用,保证了复杂地层中的锚索施工质量,加快了施工进度,取得了良好的效果。  相似文献   

潜孔锤偏心跟管钻进法在卵砾石地层岩土工程勘察中的应用     

易军  罗康生  李光俊 《贵州地质》2007,24(3):237-239

卵砾石地层是钻探工程中常见的一种典型的难钻进不稳定地层。通过采用潜孔锤偏心跟管钻进法,从根本上解决了卵砾石地层难以钻进的难题,结合都匀市区岩土工程勘察实例,笔者认为潜孔锤偏心跟管钻进法是在卵砾石地层钻进中行之有效的一种钻进法。  相似文献