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一种新型双曲弧面海堤护坡结构防潮消能效果的数值模拟研究

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水电能源科学 2024年第8期42卷 187-191页

作者：秦鹏李杰成徐欣悦周晔凯陈锴锋罗清清陶杰晖浙江水利水电学院水利与环境工程学院浙江杭州310018 浙江省农村水利水电资源配置与调控关键技术重点实验室浙江杭州310018 河海大学水利水电学院江苏南京210098

发展新型护坡结构对提高海堤工程结构强度,降低失事风险具有重要意义。为得到一种新型海堤护坡结构的更加准确的试验数据,基于Flow-3D软件对双曲弧面海堤护坡结构进行水动力数值模拟试验,并从消能防潮效果和压强分布特征等角度与传统海... 详细信息

发展新型护坡结构对提高海堤工程结构强度,降低失事风险具有重要意义。为得到一种新型海堤护坡结构的更加准确的试验数据,基于Flow-3D软件对双曲弧面海堤护坡结构进行水动力数值模拟试验,并从消能防潮效果和压强分布特征等角度与传统海堤护坡结构进行对比分析。计算结果进一步验证了新型海堤护坡结构的导流消能效果,证明其能在中、高流速涌浪冲击下有效提高越浪高度,形成较好的潮涌景观效果,同时还明晰了新型双曲海堤护坡的结构安全薄弱区域。研究成果为复杂水流条件下新型海堤护坡结构的应用及推广提供了理论及数据支撑。

关键词：双曲弧面海堤护坡防潮消能 Flow-3D 数值模拟

THE WALL EFFECT ON VENTILATED CAVITATING FLOWS IN CLOSED CAVITATION TUNNELS

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Journal of Hydrodynamics 2008年第5期20卷 561-566页

作者： CHEN Xin LU Chuan-jing li jie PAN Zhan-cheng Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China

For ventilated cavitating flows in a closed water tunnel, the wall effect may exert an important influence on cavity shape and hydrodynamics, An isotropic mixture multiphase model was established to study the wall effect based on the RANS equations, coupled with a natural cavitation model and the RNG k-ε turbulent model. The governing equations were discretized using the finite volume method and solved by the Gauss-Seidel linear equation solver on the basis of a segregation algorithm. The algebraic multigrid approach was carried through to accelerate the convergence of solution. The steady ventilated cavitating flows in water tunnels of different diameter were simulated for a conceptual underwater vehicle model which had a disk cavitator. It is found that the choked cavitation number derived is close to the approximate solution of natural cavitating flow for a 3-D disk. The critical ventilation rate falls with decreasing diameter of the water tunnel. However, the cavity size and drag coeflicient are rising with the decrease in tunnel diameter for the same ventilation rate, and the cavity size will be much different in water tunnels of different diameter even for the same ventilated cavitation number.

关键词： ventilated cavitation water tunnel choked cavitation number critical ventilation rate

一种新型双曲弧面海堤护坡结构的防浪消能效果

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长江科学院院报 2024年第4期41卷 89-94页

作者：周晔凯秦鹏李杰成匡义田蕾吴仕琪徐欣悦浙江省农村水利水电资源配置与调控关键技术重点实验室杭州310018 浙江水利水电学院水利与环境工程学院杭州310018 杭州市富阳区水利水电工程质量安全服务保障中心杭州311400

研发新型海堤护坡结构对守护人民生命安全、提高海堤工程稳定性具有重要意义。针对钱塘江河口潮流强劲,而传统海堤护面光滑,难以对强大冲击浪进行有效缓冲的工程问题,设计研发了一种具有双曲弧面结构的海堤护坡结构,采用室内水力试验和... 详细信息

研发新型海堤护坡结构对守护人民生命安全、提高海堤工程稳定性具有重要意义。针对钱塘江河口潮流强劲,而传统海堤护面光滑,难以对强大冲击浪进行有效缓冲的工程问题,设计研发了一种具有双曲弧面结构的海堤护坡结构,采用室内水力试验和数值模拟等手段对其防浪效果、压强分布特征进行分析。研究结果表明,新型海堤护面结构通过有效引导、改变冲击浪的流向及流态,既能起到较好的消能作用,又能增强钱塘江大潮的观景效果,为复杂水流条件下海堤护坡结构设计提供了新的工程思路。

关键词：双曲弧面海堤护坡室内水力试验数值模拟消能防浪

Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： cheng Wang Lan-jie li Hao Du College of Chemical Engineering University of Chinese Academy of Sciences Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of Sciences Hesteel Group Company limited

The vanadium redox flow battery(VRFB) has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high safety. However, the high preparation cost of vanadium electrolyte limits ... 详细信息

关键词： Ammonia

MADS-Box Transcription Factor AGL21 Regulates Lateral Root Development and Responds to Multiple External and Physiological Signals

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Molecular Plant 2014年第11期7卷 1653-1669页

作者： lin-Hui Yu Zi-Qing Miao Guo-Feng Qi jie Wu Xiao-Teng Cai jie-li Mao cheng-Bin Xiang School of life Sciences University of Science and Technology of China Hefei Anhui Province 230027 China

Plant root system morphology is dramatically influenced by various environmental cues. The adaptation of root system architecture to environmental constraints, which mostly depends on the formation and growth of lateral roots, is an important agronomic trait. Lateral root development is regulated by the external signals coordinating closely with intrinsic signaling pathways. MADS-box transcription factors are known key regulators of the transition to flowering and flower development. However, their functions in root development are still poorly understood. Here we report that AGL21, an AGL17-clade MADS-box gene, plays a crucial role in lateral root development. AGL21 was highly expressed in root, particularly in the root central cylinder and lateral root primordia. AGL21 overexpression plants produced more and longer lateral roots while ag121 mutants showed impaired lateral root development, especially under nitrogen-deficient conditions. AGL21 was induced by many plant hormones and environmental stresses, suggesting a function of this gene in root system plasticity in response to various signals. Furthermore, AGL21 was found positively regulating auxin accumulation in lateral root primordia and lateral roots by enhancing local auxin biosynthesis, thus stimulating lateral root initiation and growth. We propose that AGL21 may be involved in various environmental and physiological signals-mediated lateral root development and growth.

关键词： MADS root system architecture lateral root AGL21 auxin nitrate sulfate.

Activatable photoacoustic bioprobe for visual detection of aging in vivo

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Chinese Chemical Letters 2024年第4期35卷 324-329页

作者： Zihong li jie cheng Ping Huang Guoliang Wu Weiying lin Institute of Optical Materials and Chemical Biology Guangxi Key Laboratory of Electrochemical Energy MaterialsSchool of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China

Aging is a natural physiological process with various challenges, related to the loss of homeostasis within the organism, which is not a disease, but a significantly strong risk factor for multiple diseases, including myocardial infarction, stroke, some age-related cancers, macular degeneration, osteoarthritis, neurodegeneration, and many others. In the body, the main manifestation of aging is cellular aging, which exists within tissues and has a local or global impact on tissue function. However, the lack of effective aging detection tools has always been an issue that cannot be ignored in the field of aging research. Therefore,it is necessary to construct a non-invasive tool for in vivo detection of aging. Here, we show that the photoacoustic probe(LGAL), which has peak excitation and emission wavelengths in the near-infrared optical window, binds in vivo and at high contrast to the hallmark of aging, and allows for the microscopic imaging of aging through the intact mice. Firstly, this tool LGAL has been successfully applied to detect senescence in cells, displaying stronger photoacoustic signals than normal cells. Then, by using the photoacoustic probe, the blood vessels and tissues inside the mice can be visualized. Young and elderly mice exhibit varying intensities of photoacoustic signals, marking the first time a probe has been used to explore the aging of blood vessels and tissues inside the mice. Finally, we monitored the changes in the degree of aging during tumor treatment under photoacoustic(PA) imaging for the first time. As the treatment time increased, the degree of aging of the tumor gradually deepened. We expect the powerful tool could be a noninvasive and powerful tool for the study of aging biology.

关键词： Near-infrared Photoacoustic Aging Senescence Tumor Sa-β-gal

Printable,flexible ceramic fiber paper based on electrospinning

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Rare Metals 2024年第6期43卷 2739-2746页

作者： Yong-Shuai Xie Yuan cheng Yang Lyu Rui li jie-Cai Han National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Based on the fact that it is challenging for the polymer flexible circuit substrates to meet the requirements of serving in high-temperature environments,this work proposed the idea of using printable ceramic fiber paper as a high-temperature flexible circuit substrate.A ceramic fiber paper with all ceramic components had been developed via electrospinning,solving the problems of low strength and severe strength drop at high temperatures of traditional ceramic fiber *** tensile strength of the prepared ceramic fiber paper is 2.63 MPa,and the reliable service temperature is 1200℃.Its bulk density is about 1.5 times that of traditional ceramic fiber *** can be printed with patterns by commercial inkjet printers like ordinary printing paper and has excellent *** feasibility of ceramic fiber paper as a flexible circuit substrate was verified by constructing a simple *** the fiber paper is significantly bent,the circuit still forms a complete path,which proves that it has a strong application potential for high-temperature flexible circuit substrate and is expected to promote the development of flexible electronic devices serving at extreme high-temperature environments.

关键词： Ceramic fiber paper High temperature Inkjet printing Flexible electronic

Gas film/regenerative composite cooling characteristics of the liquid oxygen/liquid methane (LOX/LCH4) rocket engine

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 631-649页

作者： Xinlin liU Jun SUN Zhuohang JIANG Qinglian li Peng cheng jie SONG Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

The thermal protection of rocket engines is a crucial aspect of rocket engine *** this paper,the gas film/regenerative composite cooling of the liquid oxygen/liquid methane(LOX/LCH4)rocket engine thrust chamber was investigated.A gas film/regenerative composite cooling model was developed based on the Grisson gas film cooling efficiency formula and the one-dimensional regenerative cooling *** accuracy of the model was validated through experiments conducted on a 6 kg/s level gas film/regenerative composite cooling thrust ***,key parameters related to heat transfer performance were *** results demonstrate that the model is sufficiently accurate to be used as a preliminary design *** temperature rise error of the coolant,when compared with the experimental results,was found to be less than 10%.Although the pressure drop error is relatively large,the calculated results still provide valuable guidance for heat transfer *** addition,the performance of composite cooling is observed to be superior to regenerative *** the gas film flow rate results in higher cooling efficiency and a lower gas-side wall ***,the position at which the gas film is introduced greatly impacts the cooling *** optimal introduction position for the gas film is determined when the film is introduced from a single row of *** optimal introduction position results in a more uniform wall temperature distribution and reduces the peak ***,it is observed that a double row of holes,when compared to a single row of holes,enhances the cooling effect in the superposition area of the gas film and further lowers the gas-side wall *** results provide a basis for the design of gas film/regenerative composite cooling systems.

关键词： liquid oxygen/liquid methane(LOX/LCH4)rocket engine Gas film cooling Regenerative cooling Heat transfer characteristics

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综合物探方法在矿产资源勘查中的应用研究

世界有色金属 2024年第7期 163-165页

作者：李建平郭元华刘振兵涂登骏李承杰四川会东大梁矿业有限公司四川凉山615000

随着矿产资源勘查的深入发展,对于提高勘探效率、减少勘探成本、提高勘探精度的需求日益增加。因此,研究如何有效地应用新的综合物探方法来解决传统物探技术的局限性,具有重要的理论和实践意义。本论文旨在探讨综合物探方法在矿产资源... 详细信息

随着矿产资源勘查的深入发展,对于提高勘探效率、减少勘探成本、提高勘探精度的需求日益增加。因此,研究如何有效地应用新的综合物探方法来解决传统物探技术的局限性,具有重要的理论和实践意义。本论文旨在探讨综合物探方法在矿产资源勘查中的应用,通过分析传统物探技术的局限性,介绍新的综合物探法的原理和优势,并提出综合物探方法使用过程中的注意事项,为矿产勘探提供新的思路和方法。

关键词：综合物探方法矿产资源勘查

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