Zhijun Li

Jan 14, 2025 | nature.com | Zhijun Li

AbstractThis study investigates the critical impact of incipient sediment motion on sediment transport estimation and riverbed evolution prediction. In this research, we examine the effects of ice cover on the vertical distribution of flow velocity, establishing a mathematical relationship between the vertical average flow velocities in open channel and ice-covered flows. This leads to the derivation of a formula for incipient motion velocity under ice cover.

Dec 19, 2024 | mdpi.com | Zhijun Li

1. IntroductionThe aging of trees is a multifaceted process that involves a decline in their overall external appearance, internal structure, and physiological functions. It is a complex physiological phenomenon, with aging representing merely the final phase of a plant’s development [1]. Annual flowering plants show signs of aging and death after they bloom.

Jul 16, 2024 | mdpi.com | Xuehua Li |Lei Zhang |Zhijun Li

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Jul 10, 2024 | mdpi.com | Yanyan Wang |Yuan Qiu |Zhijun Li |Jun Tian

1. IntroductionHydraulic support is a kind of hydraulic power device that utilizes liquid pressure to generate support force and realize automatic movement to support and manage the roof. It is an indispensable supporting equipment for comprehensive mechanized coal mining [1,2,3]. However, due to its harsh working environment, the inner wall of its cylinder is easily corroded and damaged, so it needs to be rebuilt and repaired [4,5].

Apr 24, 2024 | mdpi.com | Fang Ma |Zhijun Li

All articles published by MDPI are made immediately available worldwide under an open access license. No specialpermission is required to reuse all or part of the article published by MDPI, including figures and tables. Forarticles published under an open access Creative Common CC BY license, any part of the article may be reused withoutpermission provided that the original article is clearly cited. For more information, please refer tohttps://www.mdpi.com/openaccess.