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光热纱线 1

可调控供液 1

太阳能界面海水淡化 1

盐阻塞 1

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Clogging of slurry-shield tunnel-boring machine drives in sedimentary soft rock: A case study

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0984-8

摘要： This paper presents a case study of the clogging of a slurry-shield tunnel-boring machine (TBM) experienced during tunnel operations in clay-rich argillaceous siltstones under the Ganjiang River, China. The clogging experienced during tunneling was due to special geological conditions, which had a considerably negative impact on the slurry-shield TBM tunneling performance. In this case study, the effect of clogging on the slurry-shield TBM tunneling performance (e.g., advance speed, thrust, torque, and penetration per revolution) was fully investigated. The potential for clogging during tunnel operations in argillaceous siltstone was estimated using an existing empirical classification chart. Many improvement measures have been proposed to mitigate the clogging potential of two slurry-shield TBMs during tunneling, such as the use of an optimum cutting wheel, a replacement cutting tool, improvements to the circulation flushing system and slurry properties, mixed support integrating slurry, and compressed air to support the excavation face. The mechanisms and potential causes of clogging are explained in detail, and the contributions of these mitigation measures to tunneling performance are discussed. By investigating the actual operational parameters of the slurry-shield TBMs, these mitigation measures were proven to be effective in mitigating the clogging potential of slurry-shield TBMs. This case study provides valuable information for slurry-shield TBMs involving tunneling in clay-rich sedimentary rocks.

关键词： slurry-shield TBM geological investigation clogging argillaceous siltstone TBM performance mitigation measures

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Observation of bioturbation and hyporheic flux in streambeds

Jinxi SONG, Xunhong CHEN, Cheng CHENG,

《环境科学与工程前沿（英文）》 2010年第4卷第3期页码 340-348 doi: 10.1007/s11783-010-0233-y

摘要： In the Elkhorn River, burrows, tubes, and sediment mounds created by invertebrate bioturbation were observed in the exposed streambed and commonly concentrated on the fine-sediment patches, which consist of silt, clay, and organic matter. These invertebrate activities could loosen the thin layer of clogging sediments and result in an increase of pore size in the sediments, leading to greater vertical hydraulic conductivity of the streambed (). The measurements of the vertical hydraulic gradient across the submerged streambed show that vertical flux in the hyporheic zone can alter directions (upward versus downward) for two locations only a few meters apart. In situ permeameter tests show that streambed in the upper sediment layer is much higher than that in the lower sediment layer, and the calculated in the submerged streambed is consistently greater than that in the clogged sediments around the shorelines of the sand bars. Moreover, a phenomenon of gas bubble release at the water-sediment interface from the subsurface sediments was observed in the groundwater seepage zone where flow velocity is extremely small. The bursting of gas bubbles can potentially break the thin clogging layer of sediments and enhance the vertical hydraulic conductivity of the streambed.

关键词： invertebrate bioturbation clogging hyporheic exchange streambed the Elkhorn River

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规模化制造芯鞘纱线基太阳能界面蒸发系统的供液调控和海水淡化性能 Article

肖杏芳, 潘露琪, 陈涛, 王满玉, 任李培, 陈贝, 王迎奥, 张骞, 徐卫林

《工程（英文）》 2023年第30卷第11期页码 153-160 doi: 10.1016/j.eng.2023.03.015

摘要：

调控太阳能界面蒸发系统的供液量增强局域热效应是提高其效率的有效途径。然而，由于海水淡化过程中容易盐结晶导致阻塞，在控制供液量实现局域加热过程中存在结盐的临界点，在本研究中，利用简便、可尺寸化的编织技术制备了可调控供液速率的芯鞘结构基光热纱线，实现稳定、高效的太阳能界面蒸发同时防止盐结晶。芯-鞘结构纱线由莫代尔纤维作为芯，碳纤维作为鞘。由于芯-鞘的结构设计，在碳纤维内部的超亲水莫代尔纤维可实现高效的液体输送。芯鞘结构纱线中碳纤维将芯纱完全包裹覆盖使得其编织物在整个太阳光波段具有较高的吸光性（92%）。在一个太阳光（1 kW·m⁻²）下，通过调节芯鞘纱线内莫代尔纱线的股数，可以使此系统的蒸发速率达到2.12 kg·m⁻²·h⁻¹，能量转换效率达93.7%。实际应用测试表明，此太阳能界面光热系统可以在5%（质量分数）的NaCl溶液中保持高效稳定的海水淡化性能。

关键词：太阳能界面海水淡化光热纱线可调控供液芯鞘纱盐阻塞