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排序方式: 共有899条查询结果,搜索用时 18 毫秒
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复杂地质条件下隧道施工地质超前预报往往是多种方法相互配合进行,各种信息相互补充完善,达到判断掌子面前方未知地质体工程特性的目的,以指导开挖施工的顺利进行。通过建立多重信息的综合管理信息系统,使得各种地质探测与判识信息准确、迅速反馈到施工、设计、监理等各部门为施工方案综合决策提供基础信息。以圆梁山隧道为例进行了深埋隧道施工地质超前预报信息化系统设计开发。 相似文献
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风化细粒钛铁矿及伴生金红石的选矿试验研究 总被引:3,自引:1,他引:3
就云南某地风化严重的细粒钛铁矿及伴生金红石进行了选矿试验研究,在采用弱磁选—强磁选工艺不能获得理想的指标后,采用弱磁选—强磁选—还原焙烧—弱磁选—浮选—重选—酸浸的工艺流程,获得了理想产品,铁精矿品位61.08%,回收率6.23%;钛铁精矿TiO2品位49.69%,回收率87.33%;金红石精矿TiO2品位86.57%,回收率11.77%。 相似文献
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Aerobic granular sludge in a sequencing batch reactor 总被引:88,自引:0,他引:88
E. Morgenroth T. Sherden M.C.M. Van Loosdrecht J.J. Heijnen P.A. Wilderer 《Water research》1997,31(12):3191-3194
In a laboratory scale sequencing batch reactor (SBR) granules were cultured under aerobic conditions. To enhance the growth of granular sludge the SBR was operated with very short sedimentation and draw phases resulting in the washout of slow settling biomass. Fast settling granules were retained in the reactor and thus had an advantage over flocs with a slower settling velocity. After 40 days of operation granules were the dominant form of microbial aggregates in the reactor, even though some pin-point flocs remained in the system. Granules taken from the reactor were stored for weeks without disintegrating. After about 130 days of operation the granule quality and COD-removal worsened. The reasons for that are yet to be investigated. 相似文献
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高速公路双连拱隧道施工信息化管理技术 总被引:1,自引:0,他引:1
隧道施工信息化管理技术是隧道新奥法施工的一项重要内容,它既是隧道施工安全的保证,又是对隧道支护结构进行优化的重要手段。结合小金口双连拱隧道的建设,通过对Ⅱ类围岩1-1量测断面测试数据信息的处理统计分析,首次建立了双连拱隧道结构构件的力学模型;分析和探讨了隧道围岩变形与围岩类别、开挖方法、支护时机及支护参数之间的关系;初步建立了双连拱隧道施工信息化管理技术计算机系统,这个系统由信息采集、信息传输、信息处理和信息反馈4个子系统组成。这些研究成果对类似工程也将具有重大指导意义和实际应用价值。 相似文献
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纤维面层表面非稳态过滤效率的研究 总被引:2,自引:0,他引:2
在介绍纤维过滤和颗粒过滤的基本理论基础上,根据表面过滤的“尘滤尘”现象,应用颗过滤理论建立了纤维层表面非稳态过滤效率的数学模型。对比研究表明该模型能较深刻地揭示了非稳态过滤过程随过滤进间的变化规律。从而对深化纤维过滤器的净化机理的认识,提高过滤效率,延长滤料使用寿命,加强清灰管理等方面有理论及应用意义。 相似文献
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针对低应力下钙质砂的颗粒破碎现象具有特殊性,分析了围压对钙质土颗粒的破碎的影响,揭示其变形过程的力学机制;然后考虑钙质土的颗粒破碎与滑移两种变形机制的耦合作用,并分别采用损伤模型和边界模型予以描述。理论计算与试验结果吻合较好。 相似文献
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Heavy metal-resistant immobilized sulfate-reducing bacteria (SRB) granules were prepared to treat acid mine drainage (AMD) containing high concentrations of multiple heavy metal ions using an up-flow anaerobic packed-bed bioreactor. The bioreactor demonstrated satisfactory performance at influent pH 2.8 and high concentrations of metals (Fe 463 mg/L, Mn 79 mg/L, Cu 76 mg/L, Cd 58 mg/L and Zn 118 mg/L). The effluent pH ranged from 7.8 to 8.3 and the removal efficiencies of Fe, Cu, Zn and Cd were over 99.9% except for Mn (42.1–99.3%). The bacterial community in the bioreactor was diverse and included fermentative bacteria and SRB (Desulfovibrio desulfiricans) involved in sulfate reduction. The co-existing anaerobic fermentative bacteria (Clostridia bacterium, etc.) with the ability to use lactate as electron donor could explain the differences between actual lactate consumption and what would be expected based solely on sulfate reduction. 相似文献
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Combination of mechanical and informational modeling to predict hysteresis behavior of I beam‐to‐CFT column connection 下载免费PDF全文
G.R. Abdollahzadeh S. Yapang‐Gharavi M. Hoseinali‐Beygi 《The Structural Design of Tall and Special Buildings》2018,27(3)
The behavior of beam‐to‐column connections is significantly complicated because it depends on the material, nonlinear relationship between different members, and contact of connecting elements. Their hysteretic response exhibits highly inelastic characteristics and continuous variation in stiffness, strength, and ductility. Therefore, accurate hysteretic models of bolted connections are essential to accurate seismic assessment and design. Composed (Hybrid) modeling approach is presented to represent the complex hysteretic behavior of I beam‐to‐concrete‐filled‐tube (CFT) column bolted connection. For the purpose in this study, experimental evaluation of I beam‐to‐CFT column connection with bolted end‐plate under cyclic loading is done. It must be mentioned to make the connection easily applicable practically and also prepare the column flanges continuity, a connection with the bolts penetrated into the CFT column are used since using the stiffeners in hollow sections is not easily applicable. In the composed mechanical–informational modeling framework, the conventional mechanical model is complemented by information‐based model components. Finally, moment–rotation curves of composed model have been compared with experimental results. Comparison showed that the composed model has a good agreement with experimental results. A newly designed specimen for validation purpose of the composed modeling was made and experimented. Composed model was well applied to predict the behavior of new connections. The presented results show that the composed model has a good ability to predict of hysteretic behavior. 相似文献